* [PATCH net-next] net/mlx5e: Provide cb_list pointer when setting up tc block on rep
From: Vlad Buslov @ 2019-07-10 18:25 UTC (permalink / raw)
To: netdev; +Cc: jhs, xiyou.wangcong, jiri, davem, pablo, saeedm, Vlad Buslov
Recent refactoring of tc block offloads infrastructure introduced new
flow_block_cb_setup_simple() method intended to be used as unified way for
all drivers to register offload callbacks. However, commit that actually
extended all users (drivers) with block cb list and provided it to
flow_block infra missed mlx5 en_rep. This leads to following NULL-pointer
dereference when creating Qdisc:
[ 278.385175] BUG: kernel NULL pointer dereference, address: 0000000000000000
[ 278.393233] #PF: supervisor read access in kernel mode
[ 278.399446] #PF: error_code(0x0000) - not-present page
[ 278.405847] PGD 8000000850e73067 P4D 8000000850e73067 PUD 8620cd067 PMD 0
[ 278.414141] Oops: 0000 [#1] SMP PTI
[ 278.419019] CPU: 7 PID: 3369 Comm: tc Not tainted 5.2.0-rc6+ #492
[ 278.426580] Hardware name: Supermicro SYS-2028TP-DECR/X10DRT-P, BIOS 2.0b 03/30/2017
[ 278.435853] RIP: 0010:flow_block_cb_setup_simple+0xc4/0x190
[ 278.442953] Code: 10 48 89 42 08 48 89 10 48 b8 00 01 00 00 00 00 ad de 49 89 00 48 05 00 01 00 00 49 89 40 08 31 c0 c3 b8 a1 ff ff ff c3 f3 c3 <48> 8b 06 48 39 c6 75 0a eb 1a 48 8b 00 48 39 c6 74 12
48 3b 50 28
[ 278.464829] RSP: 0018:ffffaf07c3f97990 EFLAGS: 00010246
[ 278.471648] RAX: 0000000000000000 RBX: ffff9b43ed4c7680 RCX: ffff9b43d5f80840
[ 278.480408] RDX: ffffffffc0491650 RSI: 0000000000000000 RDI: ffffaf07c3f97998
[ 278.489110] RBP: ffff9b43ddff9000 R08: ffff9b43d5f80840 R09: 0000000000000001
[ 278.497838] R10: 0000000000000009 R11: 00000000000003ad R12: ffffaf07c3f97c08
[ 278.506595] R13: ffff9b43d5f80000 R14: ffff9b43ed4c7680 R15: ffff9b43dfa20b40
[ 278.515374] FS: 00007f796be1b400(0000) GS:ffff9b43ef840000(0000) knlGS:0000000000000000
[ 278.525099] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 278.532453] CR2: 0000000000000000 CR3: 0000000840398002 CR4: 00000000001606e0
[ 278.541197] Call Trace:
[ 278.545252] tcf_block_offload_cmd.isra.52+0x7e/0xb0
[ 278.551871] tcf_block_get_ext+0x365/0x3e0
[ 278.557569] qdisc_create+0x15c/0x4e0
[ 278.562859] ? kmem_cache_alloc_trace+0x1a2/0x1c0
[ 278.569235] tc_modify_qdisc+0x1c8/0x780
[ 278.574761] rtnetlink_rcv_msg+0x291/0x340
[ 278.580518] ? _cond_resched+0x15/0x40
[ 278.585856] ? rtnl_calcit.isra.29+0x120/0x120
[ 278.591868] netlink_rcv_skb+0x4a/0x110
[ 278.597198] netlink_unicast+0x1a0/0x250
[ 278.602601] netlink_sendmsg+0x2c1/0x3c0
[ 278.608022] sock_sendmsg+0x5b/0x60
[ 278.612969] ___sys_sendmsg+0x289/0x310
[ 278.618231] ? do_wp_page+0x99/0x730
[ 278.623216] ? page_add_new_anon_rmap+0xbe/0x140
[ 278.629298] ? __handle_mm_fault+0xc84/0x1360
[ 278.635113] ? __sys_sendmsg+0x5e/0xa0
[ 278.640285] __sys_sendmsg+0x5e/0xa0
[ 278.645239] do_syscall_64+0x5b/0x1b0
[ 278.650274] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 278.656697] RIP: 0033:0x7f796abdeb87
[ 278.661628] Code: 64 89 02 48 c7 c0 ff ff ff ff eb b9 0f 1f 80 00 00 00 00 8b 05 6a 2b 2c 00 48 63 d2 48 63 ff 85 c0 75 18 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 59 f3 c3 0f 1f 80 00 00 00 00 53
48 89 f3 48
[ 278.683248] RSP: 002b:00007ffde213ba48 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[ 278.692245] RAX: ffffffffffffffda RBX: 000000005d261e6f RCX: 00007f796abdeb87
[ 278.700862] RDX: 0000000000000000 RSI: 00007ffde213bab0 RDI: 0000000000000003
[ 278.709527] RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000006
[ 278.718167] R10: 000000000000000c R11: 0000000000000246 R12: 0000000000000001
[ 278.726743] R13: 000000000067b580 R14: 0000000000000000 R15: 0000000000000000
[ 278.735302] Modules linked in: dummy vxlan ip6_udp_tunnel udp_tunnel sch_ingress nfsv3 nfs_acl nfs lockd grace fscache bridge stp llc sunrpc mlx5_ib ib_uverbs intel_rapl ib_core sb_edac x86_pkg_temp_
thermal intel_powerclamp coretemp kvm_intel kvm mlx5_core irqbypass crct10dif_pclmul crc32_pclmul crc32c_intel igb ghash_clmulni_intel ses mei_me enclosure mlxfw ipmi_ssif intel_cstate iTCO_wdt ptp mei
pps_core iTCO_vendor_support pcspkr joydev intel_uncore i2c_i801 ipmi_si lpc_ich intel_rapl_perf ioatdma wmi dca pcc_cpufreq ipmi_devintf ipmi_msghandler acpi_power_meter acpi_pad ast i2c_algo_bit drm_k
ms_helper ttm drm mpt3sas raid_class scsi_transport_sas
[ 278.802263] CR2: 0000000000000000
[ 278.807170] ---[ end trace b1f0a442a279e66f ]---
Extend en_rep with new static mlx5e_rep_block_cb_list list and pass it to
flow_block_cb_setup_simple() function instead of hardcoded NULL pointer.
Fixes: 955bcb6ea0df ("drivers: net: use flow block API")
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
---
drivers/net/ethernet/mellanox/mlx5/core/en_rep.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_rep.c b/drivers/net/ethernet/mellanox/mlx5/core/en_rep.c
index 10ef90a7bddd..7245d287633d 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_rep.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_rep.c
@@ -1175,6 +1175,8 @@ static int mlx5e_rep_setup_tc_cb(enum tc_setup_type type, void *type_data,
}
}
+static LIST_HEAD(mlx5e_rep_block_cb_list);
+
static int mlx5e_rep_setup_tc(struct net_device *dev, enum tc_setup_type type,
void *type_data)
{
@@ -1182,7 +1184,8 @@ static int mlx5e_rep_setup_tc(struct net_device *dev, enum tc_setup_type type,
switch (type) {
case TC_SETUP_BLOCK:
- return flow_block_cb_setup_simple(type_data, NULL,
+ return flow_block_cb_setup_simple(type_data,
+ &mlx5e_rep_block_cb_list,
mlx5e_rep_setup_tc_cb,
priv, priv, true);
default:
--
2.21.0
^ permalink raw reply related
* [PATCH bpf-next v9 2/2] selftests/bpf: Add selftests for bpf_perf_event_output
From: Allan Zhang @ 2019-07-10 18:18 UTC (permalink / raw)
To: netdev, bpf, songliubraving, daniel, andrii.nakryiko; +Cc: ast, allanzhang
In-Reply-To: <20190710181811.127374-1-allanzhang@google.com>
From: allanzhang <allanzhang@google.com>
Software event output is only enabled by a few prog types.
This test is to ensure that all supported types are enabled for
bpf_perf_event_output successfully.
Signed-off-by: Allan Zhang <allanzhang@google.com>
Acked-by: Song Liu <songliubraving@fb.com>
---
tools/testing/selftests/bpf/test_verifier.c | 12 ++-
.../selftests/bpf/verifier/event_output.c | 94 +++++++++++++++++++
2 files changed, 105 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/bpf/verifier/event_output.c
diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c
index c5514daf8865..5e98d7c37eb7 100644
--- a/tools/testing/selftests/bpf/test_verifier.c
+++ b/tools/testing/selftests/bpf/test_verifier.c
@@ -50,7 +50,7 @@
#define MAX_INSNS BPF_MAXINSNS
#define MAX_TEST_INSNS 1000000
#define MAX_FIXUPS 8
-#define MAX_NR_MAPS 18
+#define MAX_NR_MAPS 19
#define MAX_TEST_RUNS 8
#define POINTER_VALUE 0xcafe4all
#define TEST_DATA_LEN 64
@@ -84,6 +84,7 @@ struct bpf_test {
int fixup_map_array_wo[MAX_FIXUPS];
int fixup_map_array_small[MAX_FIXUPS];
int fixup_sk_storage_map[MAX_FIXUPS];
+ int fixup_map_event_output[MAX_FIXUPS];
const char *errstr;
const char *errstr_unpriv;
uint32_t retval, retval_unpriv, insn_processed;
@@ -627,6 +628,7 @@ static void do_test_fixup(struct bpf_test *test, enum bpf_prog_type prog_type,
int *fixup_map_array_wo = test->fixup_map_array_wo;
int *fixup_map_array_small = test->fixup_map_array_small;
int *fixup_sk_storage_map = test->fixup_sk_storage_map;
+ int *fixup_map_event_output = test->fixup_map_event_output;
if (test->fill_helper) {
test->fill_insns = calloc(MAX_TEST_INSNS, sizeof(struct bpf_insn));
@@ -788,6 +790,14 @@ static void do_test_fixup(struct bpf_test *test, enum bpf_prog_type prog_type,
fixup_sk_storage_map++;
} while (*fixup_sk_storage_map);
}
+ if (*fixup_map_event_output) {
+ map_fds[18] = __create_map(BPF_MAP_TYPE_PERF_EVENT_ARRAY,
+ sizeof(int), sizeof(int), 1, 0);
+ do {
+ prog[*fixup_map_event_output].imm = map_fds[18];
+ fixup_map_event_output++;
+ } while (*fixup_map_event_output);
+ }
}
static int set_admin(bool admin)
diff --git a/tools/testing/selftests/bpf/verifier/event_output.c b/tools/testing/selftests/bpf/verifier/event_output.c
new file mode 100644
index 000000000000..130553e19eca
--- /dev/null
+++ b/tools/testing/selftests/bpf/verifier/event_output.c
@@ -0,0 +1,94 @@
+/* instructions used to output a skb based software event, produced
+ * from code snippet:
+ * struct TMP {
+ * uint64_t tmp;
+ * } tt;
+ * tt.tmp = 5;
+ * bpf_perf_event_output(skb, &connection_tracking_event_map, 0,
+ * &tt, sizeof(tt));
+ * return 1;
+ *
+ * the bpf assembly from llvm is:
+ * 0: b7 02 00 00 05 00 00 00 r2 = 5
+ * 1: 7b 2a f8 ff 00 00 00 00 *(u64 *)(r10 - 8) = r2
+ * 2: bf a4 00 00 00 00 00 00 r4 = r10
+ * 3: 07 04 00 00 f8 ff ff ff r4 += -8
+ * 4: 18 02 00 00 00 00 00 00 00 00 00 00 00 00 00 00 r2 = 0ll
+ * 6: b7 03 00 00 00 00 00 00 r3 = 0
+ * 7: b7 05 00 00 08 00 00 00 r5 = 8
+ * 8: 85 00 00 00 19 00 00 00 call 25
+ * 9: b7 00 00 00 01 00 00 00 r0 = 1
+ * 10: 95 00 00 00 00 00 00 00 exit
+ *
+ * The reason I put the code here instead of fill_helpers is that map fixup
+ * is against the insns, instead of filled prog.
+ */
+
+#define __PERF_EVENT_INSNS__ \
+ BPF_MOV64_IMM(BPF_REG_2, 5), \
+ BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_2, -8), \
+ BPF_MOV64_REG(BPF_REG_4, BPF_REG_10), \
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, -8), \
+ BPF_LD_MAP_FD(BPF_REG_2, 0), \
+ BPF_MOV64_IMM(BPF_REG_3, 0), \
+ BPF_MOV64_IMM(BPF_REG_5, 8), \
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, \
+ BPF_FUNC_perf_event_output), \
+ BPF_MOV64_IMM(BPF_REG_0, 1), \
+ BPF_EXIT_INSN(),
+{
+ "perfevent for sockops",
+ .insns = { __PERF_EVENT_INSNS__ },
+ .prog_type = BPF_PROG_TYPE_SOCK_OPS,
+ .fixup_map_event_output = { 4 },
+ .result = ACCEPT,
+ .retval = 1,
+},
+{
+ "perfevent for tc",
+ .insns = { __PERF_EVENT_INSNS__ },
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS,
+ .fixup_map_event_output = { 4 },
+ .result = ACCEPT,
+ .retval = 1,
+},
+{
+ "perfevent for lwt out",
+ .insns = { __PERF_EVENT_INSNS__ },
+ .prog_type = BPF_PROG_TYPE_LWT_OUT,
+ .fixup_map_event_output = { 4 },
+ .result = ACCEPT,
+ .retval = 1,
+},
+{
+ "perfevent for xdp",
+ .insns = { __PERF_EVENT_INSNS__ },
+ .prog_type = BPF_PROG_TYPE_XDP,
+ .fixup_map_event_output = { 4 },
+ .result = ACCEPT,
+ .retval = 1,
+},
+{
+ "perfevent for socket filter",
+ .insns = { __PERF_EVENT_INSNS__ },
+ .prog_type = BPF_PROG_TYPE_SOCKET_FILTER,
+ .fixup_map_event_output = { 4 },
+ .result = ACCEPT,
+ .retval = 1,
+},
+{
+ "perfevent for sk_skb",
+ .insns = { __PERF_EVENT_INSNS__ },
+ .prog_type = BPF_PROG_TYPE_SK_SKB,
+ .fixup_map_event_output = { 4 },
+ .result = ACCEPT,
+ .retval = 1,
+},
+{
+ "perfevent for cgroup skb",
+ .insns = { __PERF_EVENT_INSNS__ },
+ .prog_type = BPF_PROG_TYPE_CGROUP_SKB,
+ .fixup_map_event_output = { 4 },
+ .result = ACCEPT,
+ .retval = 1,
+},
--
2.22.0.410.gd8fdbe21b5-goog
^ permalink raw reply related
* [PATCH bpf-next v9 1/2] bpf: Allow bpf_skb_event_output for a few prog types
From: Allan Zhang @ 2019-07-10 18:18 UTC (permalink / raw)
To: netdev, bpf, songliubraving, daniel, andrii.nakryiko; +Cc: ast, allanzhang
In-Reply-To: <20190710181811.127374-1-allanzhang@google.com>
From: allanzhang <allanzhang@google.com>
Software event output is only enabled by a few prog types right now (TC,
LWT out, XDP, sockops). Many other skb based prog types need
bpf_skb_event_output to produce software event.
Added socket_filter, cg_skb, sk_skb prog types to generate sw event.
Test bpf code is generated from code snippet:
struct TMP {
uint64_t tmp;
} tt;
tt.tmp = 5;
bpf_perf_event_output(skb, &connection_tracking_event_map, 0,
&tt, sizeof(tt));
return 1;
the bpf assembly from llvm is:
0: b7 02 00 00 05 00 00 00 r2 = 5
1: 7b 2a f8 ff 00 00 00 00 *(u64 *)(r10 - 8) = r2
2: bf a4 00 00 00 00 00 00 r4 = r10
3: 07 04 00 00 f8 ff ff ff r4 += -8
4: 18 02 00 00 00 00 00 00 00 00 00 00 00 00 00 00 r2 = 0ll
6: b7 03 00 00 00 00 00 00 r3 = 0
7: b7 05 00 00 08 00 00 00 r5 = 8
8: 85 00 00 00 19 00 00 00 call 25
9: b7 00 00 00 01 00 00 00 r0 = 1
10: 95 00 00 00 00 00 00 00 exit
Signed-off-by: Allan Zhang <allanzhang@google.com>
Acked-by: Song Liu <songliubraving@fb.com>
---
net/core/filter.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/net/core/filter.c b/net/core/filter.c
index 2014d76e0d2a..b75fcf412628 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -5958,6 +5958,8 @@ sk_filter_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
return &bpf_get_socket_cookie_proto;
case BPF_FUNC_get_socket_uid:
return &bpf_get_socket_uid_proto;
+ case BPF_FUNC_perf_event_output:
+ return &bpf_skb_event_output_proto;
default:
return bpf_base_func_proto(func_id);
}
@@ -5978,6 +5980,8 @@ cg_skb_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
return &bpf_sk_storage_get_proto;
case BPF_FUNC_sk_storage_delete:
return &bpf_sk_storage_delete_proto;
+ case BPF_FUNC_perf_event_output:
+ return &bpf_skb_event_output_proto;
#ifdef CONFIG_SOCK_CGROUP_DATA
case BPF_FUNC_skb_cgroup_id:
return &bpf_skb_cgroup_id_proto;
@@ -6226,6 +6230,8 @@ sk_skb_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
return &bpf_sk_redirect_map_proto;
case BPF_FUNC_sk_redirect_hash:
return &bpf_sk_redirect_hash_proto;
+ case BPF_FUNC_perf_event_output:
+ return &bpf_skb_event_output_proto;
#ifdef CONFIG_INET
case BPF_FUNC_sk_lookup_tcp:
return &bpf_sk_lookup_tcp_proto;
--
2.22.0.410.gd8fdbe21b5-goog
^ permalink raw reply related
* [PATCH bpf-next v9 0/2] bpf: Allow bpf_skb_event_output for more prog types
From: Allan Zhang @ 2019-07-10 18:18 UTC (permalink / raw)
To: netdev, bpf, songliubraving, daniel, andrii.nakryiko; +Cc: ast, Allan Zhang
Software event output is only enabled by a few prog types right now (TC,
LWT out, XDP, sockops). Many other skb based prog types need
bpf_skb_event_output to produce software event.
More prog types are enabled to access bpf_skb_event_output in this
patch.
v9 changes:
add "Acked-by" field.
v8 changes:
No actual change, just cc to netdev@vger.kernel.org and
bpf@vger.kernel.org.
v7 patches are acked by Song Liu.
v7 changes:
Reformat from hints by scripts/checkpatch.pl, including Song's comment
on signed-off-by name to captical case in cover letter.
3 of hints are ignored:
1. new file mode.
2. SPDX-License-Identifier for event_output.c since all files under
this dir have no such line.
3. "Macros ... enclosed in parentheses" for macro in event_output.c
due to code's nature.
Change patch 02 subject "bpf:..." to "selftests/bpf:..."
v6 changes:
Fix Signed-off-by, fix fixup map creation.
v5 changes:
Fix typos, reformat comments in event_output.c, move revision history to
cover letter.
v4 changes:
Reformating log message.
v3 changes:
Reformating log message.
v2 changes:
Reformating log message.
Allan Zhang (2):
bpf: Allow bpf_skb_event_output for a few prog types
selftests/bpf: Add selftests for bpf_perf_event_output
net/core/filter.c | 6 ++
tools/testing/selftests/bpf/test_verifier.c | 12 ++-
.../selftests/bpf/verifier/event_output.c | 94 +++++++++++++++++++
3 files changed, 111 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/bpf/verifier/event_output.c
--
2.22.0.410.gd8fdbe21b5-goog
^ permalink raw reply
* Re: [PATCH V2 1/1 (was 0/1 by accident)] tools/dtrace: initial implementation of DTrace
From: Kris Van Hees @ 2019-07-10 18:12 UTC (permalink / raw)
To: Kris Van Hees
Cc: netdev, bpf, dtrace-devel, linux-kernel, rostedt, mhiramat, acme,
ast, daniel, Peter Zijlstra, Chris Mason
In-Reply-To: <201907101542.x6AFgOO9012232@userv0121.oracle.com>
This patch's subject should of course be [PATCH V2 1/1] rather than 0/1.
Sorry about that.
On Wed, Jul 10, 2019 at 08:42:24AM -0700, Kris Van Hees wrote:
> This initial implementation of a tiny subset of DTrace functionality
> provides the following options:
>
> dtrace [-lvV] [-b bufsz] -s script
> -b set trace buffer size
> -l list probes (only works with '-s script' for now)
> -s enable or list probes for the specified BPF program
> -V report DTrace API version
>
> The patch comprises quite a bit of code due to DTrace requiring a few
> crucial components, even in its most basic form.
>
> The code is structured around the command line interface implemented in
> dtrace.c. It provides option parsing and drives the three modes of
> operation that are currently implemented:
>
> 1. Report DTrace API version information.
> Report the version information and terminate.
>
> 2. List probes in BPF programs.
> Initialize the list of probes that DTrace recognizes, load BPF
> programs, parse all BPF ELF section names, resolve them into
> known probes, and emit the probe names. Then terminate.
>
> 3. Load BPF programs and collect tracing data.
> Initialize the list of probes that DTrace recognizes, load BPF
> programs and attach them to their corresponding probes, set up
> perf event output buffers, and start processing tracing data.
>
> This implementation makes extensive use of BPF (handled by dt_bpf.c) and
> the perf event output ring buffer (handled by dt_buffer.c). DTrace-style
> probe handling (dt_probe.c) offers an interface to probes that hides the
> implementation details of the individual probe types by provider (dt_fbt.c
> and dt_syscall.c). Probe lookup by name uses a hashtable implementation
> (dt_hash.c). The dt_utils.c code populates a list of online CPU ids, so
> we know what CPUs we can obtain tracing data from.
>
> Building the tool is trivial because its only dependency (libbpf) is in
> the kernel tree under tools/lib/bpf. A simple 'make' in the tools/dtrace
> directory suffices.
>
> The 'dtrace' executable needs to run as root because BPF programs cannot
> be loaded by non-root users.
>
> Signed-off-by: Kris Van Hees <kris.van.hees@oracle.com>
> Reviewed-by: David Mc Lean <david.mclean@oracle.com>
> Reviewed-by: Eugene Loh <eugene.loh@oracle.com>
> ---
> Changes in v2:
> - Use ring_buffer_read_head() and ring_buffer_write_tail() to
> avoid use of volatile.
> - Handle perf events that wrap around the ring buffer boundary.
> - Remove unnecessary PERF_EVENT_IOC_ENABLE.
> - Remove -I$(srctree)/tools/perf from KBUILD_HOSTCFLAGS since it
> is not actually used.
> - Use PT_REGS_PARM1(x), etc instead of my own macros. Adding
> PT_REGS_PARM6(x) in bpf_sample.c because we need to be able to
> support up to 6 arguments passed by registers.
> ---
> MAINTAINERS | 6 +
> tools/dtrace/Makefile | 87 ++++++++++
> tools/dtrace/bpf_sample.c | 146 ++++++++++++++++
> tools/dtrace/dt_bpf.c | 185 ++++++++++++++++++++
> tools/dtrace/dt_buffer.c | 338 +++++++++++++++++++++++++++++++++++++
> tools/dtrace/dt_fbt.c | 201 ++++++++++++++++++++++
> tools/dtrace/dt_hash.c | 211 +++++++++++++++++++++++
> tools/dtrace/dt_probe.c | 230 +++++++++++++++++++++++++
> tools/dtrace/dt_syscall.c | 179 ++++++++++++++++++++
> tools/dtrace/dt_utils.c | 132 +++++++++++++++
> tools/dtrace/dtrace.c | 249 +++++++++++++++++++++++++++
> tools/dtrace/dtrace.h | 13 ++
> tools/dtrace/dtrace_impl.h | 101 +++++++++++
> 13 files changed, 2078 insertions(+)
> create mode 100644 tools/dtrace/Makefile
> create mode 100644 tools/dtrace/bpf_sample.c
> create mode 100644 tools/dtrace/dt_bpf.c
> create mode 100644 tools/dtrace/dt_buffer.c
> create mode 100644 tools/dtrace/dt_fbt.c
> create mode 100644 tools/dtrace/dt_hash.c
> create mode 100644 tools/dtrace/dt_probe.c
> create mode 100644 tools/dtrace/dt_syscall.c
> create mode 100644 tools/dtrace/dt_utils.c
> create mode 100644 tools/dtrace/dtrace.c
> create mode 100644 tools/dtrace/dtrace.h
> create mode 100644 tools/dtrace/dtrace_impl.h
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index cfa9ed89c031..410240732d55 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -5485,6 +5485,12 @@ W: https://linuxtv.org
> S: Odd Fixes
> F: drivers/media/pci/dt3155/
>
> +DTRACE
> +M: Kris Van Hees <kris.van.hees@oracle.com>
> +L: dtrace-devel@oss.oracle.com
> +S: Maintained
> +F: tools/dtrace/
> +
> DVB_USB_AF9015 MEDIA DRIVER
> M: Antti Palosaari <crope@iki.fi>
> L: linux-media@vger.kernel.org
> diff --git a/tools/dtrace/Makefile b/tools/dtrace/Makefile
> new file mode 100644
> index 000000000000..03ae498d1429
> --- /dev/null
> +++ b/tools/dtrace/Makefile
> @@ -0,0 +1,87 @@
> +# SPDX-License-Identifier: GPL-2.0
> +#
> +# This Makefile is based on samples/bpf.
> +#
> +# Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
> +
> +DT_VERSION := 2.0.0
> +DT_GIT_VERSION := $(shell git rev-parse HEAD 2>/dev/null || \
> + echo Unknown)
> +
> +DTRACE_PATH ?= $(abspath $(srctree)/$(src))
> +TOOLS_PATH := $(DTRACE_PATH)/..
> +SAMPLES_PATH := $(DTRACE_PATH)/../../samples
> +
> +hostprogs-y := dtrace
> +
> +LIBBPF := $(TOOLS_PATH)/lib/bpf/libbpf.a
> +OBJS := dt_bpf.o dt_buffer.o dt_utils.o dt_probe.o \
> + dt_hash.o \
> + dt_fbt.o dt_syscall.o
> +
> +dtrace-objs := $(OBJS) dtrace.o
> +
> +always := $(hostprogs-y)
> +always += bpf_sample.o
> +
> +KBUILD_HOSTCFLAGS += -DDT_VERSION=\"$(DT_VERSION)\"
> +KBUILD_HOSTCFLAGS += -DDT_GIT_VERSION=\"$(DT_GIT_VERSION)\"
> +KBUILD_HOSTCFLAGS += -I$(srctree)/tools/lib
> +KBUILD_HOSTCFLAGS += -I$(srctree)/tools/include/uapi
> +KBUILD_HOSTCFLAGS += -I$(srctree)/tools/include/
> +KBUILD_HOSTCFLAGS += -I$(srctree)/usr/include
> +
> +KBUILD_HOSTLDLIBS := $(LIBBPF) -lelf
> +
> +LLC ?= llc
> +CLANG ?= clang
> +LLVM_OBJCOPY ?= llvm-objcopy
> +
> +ifdef CROSS_COMPILE
> +HOSTCC = $(CROSS_COMPILE)gcc
> +CLANG_ARCH_ARGS = -target $(ARCH)
> +endif
> +
> +all:
> + $(MAKE) -C ../../ $(CURDIR)/ DTRACE_PATH=$(CURDIR)
> +
> +clean:
> + $(MAKE) -C ../../ M=$(CURDIR) clean
> + @rm -f *~
> +
> +$(LIBBPF): FORCE
> + $(MAKE) -C $(dir $@) RM='rm -rf' LDFLAGS= srctree=$(DTRACE_PATH)/../../ O=
> +
> +FORCE:
> +
> +.PHONY: verify_cmds verify_target_bpf $(CLANG) $(LLC)
> +
> +verify_cmds: $(CLANG) $(LLC)
> + @for TOOL in $^ ; do \
> + if ! (which -- "$${TOOL}" > /dev/null 2>&1); then \
> + echo "*** ERROR: Cannot find LLVM tool $${TOOL}" ;\
> + exit 1; \
> + else true; fi; \
> + done
> +
> +verify_target_bpf: verify_cmds
> + @if ! (${LLC} -march=bpf -mattr=help > /dev/null 2>&1); then \
> + echo "*** ERROR: LLVM (${LLC}) does not support 'bpf' target" ;\
> + echo " NOTICE: LLVM version >= 3.7.1 required" ;\
> + exit 2; \
> + else true; fi
> +
> +$(DTRACE_PATH)/*.c: verify_target_bpf $(LIBBPF)
> +$(src)/*.c: verify_target_bpf $(LIBBPF)
> +
> +$(obj)/%.o: $(src)/%.c
> + @echo " CLANG-bpf " $@
> + $(Q)$(CLANG) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) $(EXTRA_CFLAGS) -I$(obj) \
> + -I$(srctree)/tools/testing/selftests/bpf/ \
> + -D__KERNEL__ -D__BPF_TRACING__ -Wno-unused-value -Wno-pointer-sign \
> + -D__TARGET_ARCH_$(ARCH) -Wno-compare-distinct-pointer-types \
> + -Wno-gnu-variable-sized-type-not-at-end \
> + -Wno-address-of-packed-member -Wno-tautological-compare \
> + -Wno-unknown-warning-option $(CLANG_ARCH_ARGS) \
> + -I$(srctree)/samples/bpf/ -include asm_goto_workaround.h \
> + -O2 -emit-llvm -c $< -o -| $(LLC) -march=bpf $(LLC_FLAGS) -filetype=obj -o $@
> diff --git a/tools/dtrace/bpf_sample.c b/tools/dtrace/bpf_sample.c
> new file mode 100644
> index 000000000000..9862f75f92d3
> --- /dev/null
> +++ b/tools/dtrace/bpf_sample.c
> @@ -0,0 +1,146 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * This sample DTrace BPF tracing program demonstrates how actions can be
> + * associated with different probe types.
> + *
> + * The kprobe/ksys_write probe is a Function Boundary Tracing (FBT) entry probe
> + * on the ksys_write(fd, buf, count) function in the kernel. Arguments to the
> + * function can be retrieved from the CPU registers (struct pt_regs).
> + *
> + * The tracepoint/syscalls/sys_enter_write probe is a System Call entry probe
> + * for the write(d, buf, count) system call. Arguments to the system call can
> + * be retrieved from the tracepoint data passed to the BPF program as context
> + * struct syscall_data) when the probe fires.
> + *
> + * The BPF program associated with each probe prepares a DTrace BPF context
> + * (struct dt_bpf_context) that stores the probe ID and up to 10 arguments.
> + * Only 3 arguments are used in this sample. Then the prorgams call a shared
> + * BPF function (bpf_action) that implements the actual action to be taken when
> + * a probe fires. It prepares a data record to be stored in the tracing buffer
> + * and submits it to the buffer. The data in the data record is obtained from
> + * the DTrace BPF context.
> + *
> + * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
> + */
> +#include <uapi/linux/bpf.h>
> +#include <linux/ptrace.h>
> +#include <linux/version.h>
> +#include <uapi/linux/unistd.h>
> +#include "bpf_helpers.h"
> +
> +#include "dtrace.h"
> +
> +struct syscall_data {
> + struct pt_regs *regs;
> + long syscall_nr;
> + long arg[6];
> +};
> +
> +struct bpf_map_def SEC("maps") buffers = {
> + .type = BPF_MAP_TYPE_PERF_EVENT_ARRAY,
> + .key_size = sizeof(u32),
> + .value_size = sizeof(u32),
> + .max_entries = NR_CPUS,
> +};
> +
> +#if defined(bpf_target_x86)
> +# define PT_REGS_PARM6(x) ((x)->r9)
> +#elif defined(bpf_target_s390x)
> +# define PT_REGS_PARM6(x) ((x)->gprs[7])
> +#elif defined(bpf_target_arm)
> +# define PT_REGS_PARM6(x) ((x)->uregs[5])
> +#elif defined(bpf_target_arm64)
> +# define PT_REGS_PARM6(x) ((x)->regs[5])
> +#elif defined(bpf_target_mips)
> +# define PT_REGS_PARM6(x) ((x)->regs[9])
> +#elif defined(bpf_target_powerpc)
> +# define PT_REGS_PARM6(x) ((x)->gpr[8])
> +#elif defined(bpf_target_sparc)
> +# define PT_REGS_PARM6(x) ((x)->u_regs[UREG_I5])
> +#else
> +# error Argument retrieval from pt_regs is not supported yet on this arch.
> +#endif
> +
> +/*
> + * We must pass a valid BPF context pointer because the bpf_perf_event_output()
> + * helper requires a BPF context pointer as first argument (and the verifier is
> + * validating that we pass a value that is known to be a context pointer).
> + *
> + * This BPF function implements the following D action:
> + * {
> + * trace(curthread);
> + * trace(arg0);
> + * trace(arg1);
> + * trace(arg2);
> + * }
> + *
> + * Expected output will look like:
> + * CPU ID
> + * 15 70423 0xffff8c0968bf8ec0 0x00000000000001 0x0055e019eb3f60 0x0000000000002c
> + * 15 18876 0xffff8c0968bf8ec0 0x00000000000001 0x0055e019eb3f60 0x0000000000002c
> + * | | +-- curthread +--> arg0 (fd) +--> arg1 (buf) +-- arg2 (count)
> + * | |
> + * | +--> probe ID
> + * |
> + * +--> CPU the probe fired on
> + */
> +static noinline int bpf_action(void *bpf_ctx, struct dt_bpf_context *ctx)
> +{
> + int cpu = bpf_get_smp_processor_id();
> + struct data {
> + u32 probe_id; /* mandatory */
> +
> + u64 task; /* first data item (current task) */
> + u64 arg0; /* 2nd data item (arg0, fd) */
> + u64 arg1; /* 3rd data item (arg1, buf) */
> + u64 arg2; /* 4th data item (arg2, count) */
> + } rec;
> +
> + memset(&rec, 0, sizeof(rec));
> +
> + rec.probe_id = ctx->probe_id;
> + rec.task = bpf_get_current_task();
> + rec.arg0 = ctx->argv[0];
> + rec.arg1 = ctx->argv[1];
> + rec.arg2 = ctx->argv[2];
> +
> + bpf_perf_event_output(bpf_ctx, &buffers, cpu, &rec, sizeof(rec));
> +
> + return 0;
> +}
> +
> +SEC("kprobe/ksys_write")
> +int bpf_kprobe(struct pt_regs *regs)
> +{
> + struct dt_bpf_context ctx;
> +
> + memset(&ctx, 0, sizeof(ctx));
> +
> + ctx.probe_id = 18876;
> + ctx.argv[0] = PT_REGS_PARM1(regs);
> + ctx.argv[1] = PT_REGS_PARM2(regs);
> + ctx.argv[2] = PT_REGS_PARM3(regs);
> + ctx.argv[3] = PT_REGS_PARM4(regs);
> + ctx.argv[4] = PT_REGS_PARM5(regs);
> + ctx.argv[5] = PT_REGS_PARM6(regs);
> +
> + return bpf_action(regs, &ctx);
> +}
> +
> +SEC("tracepoint/syscalls/sys_enter_write")
> +int bpf_tp(struct syscall_data *scd)
> +{
> + struct dt_bpf_context ctx;
> +
> + memset(&ctx, 0, sizeof(ctx));
> +
> + ctx.probe_id = 70423;
> + ctx.argv[0] = scd->arg[0];
> + ctx.argv[1] = scd->arg[1];
> + ctx.argv[2] = scd->arg[2];
> +
> + return bpf_action(scd, &ctx);
> +}
> +
> +char _license[] SEC("license") = "GPL";
> +u32 _version SEC("version") = LINUX_VERSION_CODE;
> diff --git a/tools/dtrace/dt_bpf.c b/tools/dtrace/dt_bpf.c
> new file mode 100644
> index 000000000000..78c90de016c6
> --- /dev/null
> +++ b/tools/dtrace/dt_bpf.c
> @@ -0,0 +1,185 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * This file provides the interface for handling BPF. It uses the bpf library
> + * to interact with BPF ELF object files.
> + *
> + * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
> + */
> +#include <errno.h>
> +#include <stdarg.h>
> +#include <stdio.h>
> +#include <string.h>
> +#include <unistd.h>
> +#include <bpf/libbpf.h>
> +#include <linux/kernel.h>
> +#include <linux/perf_event.h>
> +#include <sys/ioctl.h>
> +
> +#include "dtrace_impl.h"
> +
> +/*
> + * Validate the output buffer map that is specified in the BPF ELF object. It
> + * must match the following definition to be valid:
> + *
> + * struct bpf_map_def SEC("maps") buffers = {
> + * .type = BPF_MAP_TYPE_PERF_EVENT_ARRAY,
> + * .key_size = sizeof(u32),
> + * .value_size = sizeof(u32),
> + * .max_entries = num,
> + * };
> + * where num is greater than dt_maxcpuid.
> + */
> +static int is_valid_buffers(const struct bpf_map_def *mdef)
> +{
> + return mdef->type == BPF_MAP_TYPE_PERF_EVENT_ARRAY &&
> + mdef->key_size == sizeof(u32) &&
> + mdef->value_size == sizeof(u32) &&
> + mdef->max_entries > dt_maxcpuid;
> +}
> +
> +/*
> + * List the probes specified in the given BPF ELF object file.
> + */
> +int dt_bpf_list_probes(const char *fn)
> +{
> + struct bpf_object *obj;
> + struct bpf_program *prog;
> + int rc, fd;
> +
> + libbpf_set_print(NULL);
> +
> + /*
> + * Listing probes is done before the DTrace command line utility loads
> + * the supplied programs. We load them here without attaching them to
> + * probes so that we can retrieve the ELF section names for each BPF
> + * program. The section name indicates the probe that the program is
> + * associated with.
> + */
> + rc = bpf_prog_load(fn, BPF_PROG_TYPE_UNSPEC, &obj, &fd);
> + if (rc)
> + return rc;
> +
> + /*
> + * Loop through the programs in the BPF ELF object, and try to resolve
> + * the section names into probes. Use the supplied callback function
> + * to emit the probe description.
> + */
> + for (prog = bpf_program__next(NULL, obj); prog != NULL;
> + prog = bpf_program__next(prog, obj)) {
> + struct dt_probe *probe;
> +
> + probe = dt_probe_resolve_event(bpf_program__title(prog, false));
> +
> + printf("%5d %10s %17s %33s %s\n", probe->id,
> + probe->prv_name ? probe->prv_name : "",
> + probe->mod_name ? probe->mod_name : "",
> + probe->fun_name ? probe->fun_name : "",
> + probe->prb_name ? probe->prb_name : "");
> + }
> +
> +
> + /* Done with the BPF ELF object. */
> + bpf_object__close(obj);
> +
> + return 0;
> +}
> +
> +/*
> + * Load the given BPF ELF object file.
> + */
> +int dt_bpf_load_file(const char *fn)
> +{
> + struct bpf_object *obj;
> + struct bpf_map *map;
> + struct bpf_program *prog;
> + int rc, fd;
> +
> + libbpf_set_print(NULL);
> +
> + /* Load the BPF ELF object file. */
> + rc = bpf_prog_load(fn, BPF_PROG_TYPE_UNSPEC, &obj, &fd);
> + if (rc)
> + return rc;
> +
> + /* Validate buffers map. */
> + map = bpf_object__find_map_by_name(obj, "buffers");
> + if (map && is_valid_buffers(bpf_map__def(map)))
> + dt_bufmap_fd = bpf_map__fd(map);
> + else
> + goto fail;
> +
> + /*
> + * Loop through the programs and resolve each into the matching probe.
> + * Attach the program to the probe.
> + */
> + for (prog = bpf_program__next(NULL, obj); prog != NULL;
> + prog = bpf_program__next(prog, obj)) {
> + struct dt_probe *probe;
> +
> + probe = dt_probe_resolve_event(bpf_program__title(prog, false));
> + if (!probe)
> + return -ENOENT;
> + if (probe->prov && probe->prov->attach)
> + probe->prov->attach(bpf_program__title(prog, false),
> + bpf_program__fd(prog));
> + }
> +
> + return 0;
> +
> +fail:
> + bpf_object__close(obj);
> + return -EINVAL;
> +}
> +
> +/*
> + * Store the (key, value) pair in the map referenced by the given fd.
> + */
> +int dt_bpf_map_update(int fd, const void *key, const void *val)
> +{
> + union bpf_attr attr;
> +
> + memset(&attr, 0, sizeof(attr));
> +
> + attr.map_fd = fd;
> + attr.key = (u64)(unsigned long)key;
> + attr.value = (u64)(unsigned long)val;
> + attr.flags = 0;
> +
> + return bpf(BPF_MAP_UPDATE_ELEM, &attr);
> +}
> +
> +/*
> + * Attach a trace event and associate a BPF program with it.
> + */
> +int dt_bpf_attach(int event_id, int bpf_fd)
> +{
> + int event_fd;
> + int rc;
> + struct perf_event_attr attr = {};
> +
> + attr.type = PERF_TYPE_TRACEPOINT;
> + attr.sample_type = PERF_SAMPLE_RAW;
> + attr.sample_period = 1;
> + attr.wakeup_events = 1;
> + attr.config = event_id;
> +
> + /*
> + * Register the event (based on its id), and obtain a fd. It gets
> + * created as an enabled probe, so we don't have to explicitly enable
> + * it.
> + */
> + event_fd = perf_event_open(&attr, -1, 0, -1, 0);
> + if (event_fd < 0) {
> + perror("sys_perf_event_open");
> + return -1;
> + }
> +
> + /* Associate the BPF program with the event. */
> + rc = ioctl(event_fd, PERF_EVENT_IOC_SET_BPF, bpf_fd);
> + if (rc < 0) {
> + perror("PERF_EVENT_IOC_SET_BPF");
> + return -1;
> + }
> +
> + return 0;
> +}
> diff --git a/tools/dtrace/dt_buffer.c b/tools/dtrace/dt_buffer.c
> new file mode 100644
> index 000000000000..19bb7e4cfc92
> --- /dev/null
> +++ b/tools/dtrace/dt_buffer.c
> @@ -0,0 +1,338 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * This file provides the tracing buffer handling for DTrace. It makes use of
> + * the perf event output ring buffers that can be written to from BPF programs.
> + *
> + * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
> + */
> +#include <errno.h>
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include <string.h>
> +#include <syscall.h>
> +#include <unistd.h>
> +#include <sys/epoll.h>
> +#include <sys/ioctl.h>
> +#include <sys/mman.h>
> +#include <linux/bpf.h>
> +#include <linux/perf_event.h>
> +#include <linux/ring_buffer.h>
> +
> +#include "dtrace_impl.h"
> +
> +/*
> + * Probe data is recorded in per-CPU perf ring buffers.
> + */
> +struct dtrace_buffer {
> + int cpu; /* ID of CPU that uses this buffer */
> + int fd; /* fd of perf output buffer */
> + size_t page_size; /* size of each page in buffer */
> + size_t data_size; /* total buffer size */
> + u8 *base; /* address of buffer */
> + u8 *endp; /* address of end of buffer */
> + u8 *tmp; /* temporary event buffer */
> + u32 tmp_len; /* length of temporary event buffer */
> +};
> +
> +static struct dtrace_buffer *dt_buffers;
> +
> +/*
> + * File descriptor for the BPF map that holds the buffers for the online CPUs.
> + * The map is a bpf_array indexed by CPU id, and it stores a file descriptor as
> + * value (the fd for the perf_event that represents the CPU buffer).
> + */
> +int dt_bufmap_fd = -1;
> +
> +/*
> + * Create a perf_event buffer for the given DTrace buffer. This will create
> + * a perf_event ring_buffer, mmap it, and enable the perf_event that owns the
> + * buffer.
> + */
> +static int perf_buffer_open(struct dtrace_buffer *buf)
> +{
> + int pefd;
> + struct perf_event_attr attr = {};
> +
> + /*
> + * Event configuration for BPF-generated output in perf_event ring
> + * buffers. The event is created in enabled state.
> + */
> + attr.config = PERF_COUNT_SW_BPF_OUTPUT;
> + attr.type = PERF_TYPE_SOFTWARE;
> + attr.sample_type = PERF_SAMPLE_RAW;
> + attr.sample_period = 1;
> + attr.wakeup_events = 1;
> + pefd = perf_event_open(&attr, -1, buf->cpu, -1, PERF_FLAG_FD_CLOEXEC);
> + if (pefd < 0) {
> + fprintf(stderr, "perf_event_open(cpu %d): %s\n", buf->cpu,
> + strerror(errno));
> + goto fail;
> + }
> +
> + /*
> + * We add buf->page_size to the buf->data_size, because perf maintains
> + * a meta-data page at the beginning of the memory region. That page
> + * is used for reader/writer symchronization.
> + */
> + buf->fd = pefd;
> + buf->base = mmap(NULL, buf->page_size + buf->data_size,
> + PROT_READ | PROT_WRITE, MAP_SHARED, buf->fd, 0);
> + buf->endp = buf->base + buf->page_size + buf->data_size - 1;
> + if (!buf->base)
> + goto fail;
> +
> + return 0;
> +
> +fail:
> + if (buf->base) {
> + munmap(buf->base, buf->page_size + buf->data_size);
> + buf->base = NULL;
> + buf->endp = NULL;
> + }
> + if (buf->fd) {
> + close(buf->fd);
> + buf->fd = -1;
> + }
> +
> + return -1;
> +}
> +
> +/*
> + * Close the given DTrace buffer. This function disables the perf_event that
> + * owns the buffer, munmaps the memory space, and closes the perf buffer fd.
> + */
> +static void perf_buffer_close(struct dtrace_buffer *buf)
> +{
> + /*
> + * If the perf buffer failed to open, there is no need to close it.
> + */
> + if (buf->fd < 0)
> + return;
> +
> + if (ioctl(buf->fd, PERF_EVENT_IOC_DISABLE, 0) < 0)
> + fprintf(stderr, "PERF_EVENT_IOC_DISABLE(cpu %d): %s\n",
> + buf->cpu, strerror(errno));
> +
> + munmap(buf->base, buf->page_size + buf->data_size);
> +
> + if (close(buf->fd))
> + fprintf(stderr, "perf buffer close(cpu %d): %s\n",
> + buf->cpu, strerror(errno));
> +
> + buf->base = NULL;
> + buf->fd = -1;
> +}
> +
> +/*
> + * Initialize the probe data buffers (one per online CPU). Each buffer will
> + * contain the given number of pages (i.e. total size of each buffer will be
> + * num_pages * getpagesize()). This function also sets up an event polling
> + * descriptor that monitors all CPU buffers at once.
> + */
> +int dt_buffer_init(int num_pages)
> +{
> + int i;
> + int epoll_fd;
> +
> + if (dt_bufmap_fd < 0)
> + return -EINVAL;
> +
> + /* Allocate the per-CPU buffer structs. */
> + dt_buffers = calloc(dt_numcpus, sizeof(struct dtrace_buffer));
> + if (dt_buffers == NULL)
> + return -ENOMEM;
> +
> + /* Set up the event polling file descriptor. */
> + epoll_fd = epoll_create1(EPOLL_CLOEXEC);
> + if (epoll_fd < 0) {
> + free(dt_buffers);
> + return -errno;
> + }
> +
> + for (i = 0; i < dt_numcpus; i++) {
> + int cpu = dt_cpuids[i];
> + struct epoll_event ev;
> + struct dtrace_buffer *buf = &dt_buffers[i];
> +
> + buf->cpu = cpu;
> + buf->page_size = getpagesize();
> + buf->data_size = num_pages * buf->page_size;
> + buf->tmp = NULL;
> + buf->tmp_len = 0;
> +
> + /* Try to create the perf buffer for this DTrace buffer. */
> + if (perf_buffer_open(buf) == -1)
> + continue;
> +
> + /* Store the perf buffer fd in the buffer map. */
> + dt_bpf_map_update(dt_bufmap_fd, &cpu, &buf->fd);
> +
> + /* Add the buffer to the event polling descriptor. */
> + ev.events = EPOLLIN;
> + ev.data.ptr = buf;
> + if (epoll_ctl(epoll_fd, EPOLL_CTL_ADD, buf->fd, &ev) == -1) {
> + fprintf(stderr, "EPOLL_CTL_ADD(cpu %d): %s\n",
> + buf->cpu, strerror(errno));
> + continue;
> + }
> + }
> +
> + return epoll_fd;
> +}
> +
> +/*
> + * Clean up the buffers.
> + */
> +void dt_buffer_exit(int epoll_fd)
> +{
> + int i;
> +
> + for (i = 0; i < dt_numcpus; i++)
> + perf_buffer_close(&dt_buffers[i]);
> +
> + free(dt_buffers);
> + close(epoll_fd);
> +}
> +
> +/*
> + * Process and output the probe data at the supplied address.
> + */
> +static void output_event(int cpu, u64 *buf)
> +{
> + u8 *data = (u8 *)buf;
> + struct perf_event_header *hdr;
> +
> + hdr = (struct perf_event_header *)data;
> + data += sizeof(struct perf_event_header);
> +
> + if (hdr->type == PERF_RECORD_SAMPLE) {
> + u8 *ptr = data;
> + u32 i, size, probe_id;
> +
> + /*
> + * struct {
> + * struct perf_event_header header;
> + * u32 size;
> + * u32 probe_id;
> + * u32 gap;
> + * u64 data[n];
> + * }
> + * and data points to the 'size' member at this point.
> + */
> + if (ptr > (u8 *)buf + hdr->size) {
> + fprintf(stderr, "BAD: corrupted sample header\n");
> + return;
> + }
> +
> + size = *(u32 *)data;
> + data += sizeof(size);
> + ptr += sizeof(size) + size;
> + if (ptr != (u8 *)buf + hdr->size) {
> + fprintf(stderr, "BAD: invalid sample size\n");
> + return;
> + }
> +
> + probe_id = *(u32 *)data;
> + data += sizeof(probe_id);
> + size -= sizeof(probe_id);
> + data += sizeof(u32); /* skip 32-bit gap */
> + size -= sizeof(u32);
> + buf = (u64 *)data;
> +
> + printf("%3d %6d ", cpu, probe_id);
> + for (i = 0, size /= sizeof(u64); i < size; i++)
> + printf("%#016lx ", buf[i]);
> + printf("\n");
> + } else if (hdr->type == PERF_RECORD_LOST) {
> + u64 lost;
> +
> + /*
> + * struct {
> + * struct perf_event_header header;
> + * u64 id;
> + * u64 lost;
> + * }
> + * and data points to the 'id' member at this point.
> + */
> + lost = *(u64 *)(data + sizeof(u64));
> +
> + printf("[%ld probes dropped]\n", lost);
> + } else
> + fprintf(stderr, "UNKNOWN: record type %d\n", hdr->type);
> +}
> +
> +/*
> + * Process the available probe data in the given buffer.
> + */
> +static void process_data(struct dtrace_buffer *buf)
> +{
> + struct perf_event_mmap_page *rb_page = (void *)buf->base;
> + struct perf_event_header *hdr;
> + u8 *base;
> + u64 head, tail;
> +
> + /* Set base to be the start of the buffer data. */
> + base = buf->base + buf->page_size;
> +
> + for (;;) {
> + head = ring_buffer_read_head(rb_page);
> + tail = rb_page->data_tail;
> +
> + if (tail == head)
> + break;
> +
> + do {
> + u8 *event = base + tail % buf->data_size;
> + u32 len;
> +
> + hdr = (struct perf_event_header *)event;
> + len = hdr->size;
> +
> + /*
> + * If the perf event data wraps around the boundary of
> + * the buffer, we make a copy in contiguous memory.
> + */
> + if (event + len > buf->endp) {
> + u8 *dst;
> + u32 num;
> +
> + /* Increase buffer as needed. */
> + if (buf->tmp_len < len) {
> + buf->tmp = realloc(buf->tmp, len);
> + buf->tmp_len = len;
> + }
> +
> + dst = buf->tmp;
> + num = buf->endp - event + 1;
> + memcpy(dst, event, num);
> + memcpy(dst + num, base, len - num);
> +
> + event = dst;
> + }
> +
> + output_event(buf->cpu, (u64 *)event);
> +
> + tail += hdr->size;
> + } while (tail != head);
> +
> + ring_buffer_write_tail(rb_page, tail);
> + }
> +}
> +
> +/*
> + * Wait for data to become available in any of the buffers.
> + */
> +int dt_buffer_poll(int epoll_fd, int timeout)
> +{
> + struct epoll_event events[dt_numcpus];
> + int i, cnt;
> +
> + cnt = epoll_wait(epoll_fd, events, dt_numcpus, timeout);
> + if (cnt < 0)
> + return -errno;
> +
> + for (i = 0; i < cnt; i++)
> + process_data((struct dtrace_buffer *)events[i].data.ptr);
> +
> + return cnt;
> +}
> diff --git a/tools/dtrace/dt_fbt.c b/tools/dtrace/dt_fbt.c
> new file mode 100644
> index 000000000000..fcf95243bf97
> --- /dev/null
> +++ b/tools/dtrace/dt_fbt.c
> @@ -0,0 +1,201 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * The Function Boundary Tracing (FBT) provider for DTrace.
> + *
> + * FBT probes are exposed by the kernel as kprobes. They are listed in the
> + * TRACEFS/available_filter_functions file. Some kprobes are associated with
> + * a specific kernel module, while most are in the core kernel.
> + *
> + * Mapping from event name to DTrace probe name:
> + *
> + * <name> fbt:vmlinux:<name>:entry
> + * fbt:vmlinux:<name>:return
> + * or
> + * <name> [<modname>] fbt:<modname>:<name>:entry
> + * fbt:<modname>:<name>:return
> + *
> + * Mapping from BPF section name to DTrace probe name:
> + *
> + * kprobe/<name> fbt:vmlinux:<name>:entry
> + * kretprobe/<name> fbt:vmlinux:<name>:return
> + *
> + * (Note that the BPF section does not carry information about the module that
> + * the function is found in. This means that BPF section name cannot be used
> + * to distinguish between functions with the same name occurring in different
> + * modules.)
> + *
> + * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
> + */
> +#include <fcntl.h>
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include <string.h>
> +#include <unistd.h>
> +#include <linux/bpf.h>
> +#include <sys/stat.h>
> +#include <sys/types.h>
> +
> +#include "dtrace_impl.h"
> +
> +#define KPROBE_EVENTS TRACEFS "kprobe_events"
> +#define PROBE_LIST TRACEFS "available_filter_functions"
> +
> +static const char provname[] = "fbt";
> +static const char modname[] = "vmlinux";
> +
> +/*
> + * Scan the PROBE_LIST file and add entry and return probes for every function
> + * that is listed.
> + */
> +static int fbt_populate(void)
> +{
> + FILE *f;
> + char buf[256];
> + char *p;
> +
> + f = fopen(PROBE_LIST, "r");
> + if (f == NULL)
> + return -1;
> +
> + while (fgets(buf, sizeof(buf), f)) {
> + /*
> + * Here buf is either "funcname\n" or "funcname [modname]\n".
> + */
> + p = strchr(buf, '\n');
> + if (p) {
> + *p = '\0';
> + if (p > buf && *(--p) == ']')
> + *p = '\0';
> + } else {
> + /* If we didn't see a newline, the line was too long.
> + * Report it, and continue until the end of the line.
> + */
> + fprintf(stderr, "%s: Line too long: %s\n",
> + PROBE_LIST, buf);
> + do
> + fgets(buf, sizeof(buf), f);
> + while (strchr(buf, '\n') == NULL);
> + continue;
> + }
> +
> + /*
> + * Now buf is either "funcname" or "funcname [modname". If
> + * there is no module name provided, we will use the default.
> + */
> + p = strchr(buf, ' ');
> + if (p) {
> + *p++ = '\0';
> + if (*p == '[')
> + p++;
> + }
> +
> + dt_probe_new(&dt_fbt, provname, p ? p : modname, buf, "entry");
> + dt_probe_new(&dt_fbt, provname, p ? p : modname, buf, "return");
> + }
> +
> + fclose(f);
> +
> + return 0;
> +}
> +
> +#define ENTRY_PREFIX "kprobe/"
> +#define EXIT_PREFIX "kretprobe/"
> +
> +/*
> + * Perform a probe lookup based on an event name (BPF ELF section name).
> + */
> +static struct dt_probe *fbt_resolve_event(const char *name)
> +{
> + const char *prbname;
> + struct dt_probe tmpl;
> + struct dt_probe *probe;
> +
> + if (!name)
> + return NULL;
> +
> + if (strncmp(name, ENTRY_PREFIX, sizeof(ENTRY_PREFIX) - 1) == 0) {
> + name += sizeof(ENTRY_PREFIX) - 1;
> + prbname = "entry";
> + } else if (strncmp(name, EXIT_PREFIX, sizeof(EXIT_PREFIX) - 1) == 0) {
> + name += sizeof(EXIT_PREFIX) - 1;
> + prbname = "return";
> + } else
> + return NULL;
> +
> + memset(&tmpl, 0, sizeof(tmpl));
> + tmpl.prv_name = provname;
> + tmpl.mod_name = modname;
> + tmpl.fun_name = name;
> + tmpl.prb_name = prbname;
> +
> + probe = dt_probe_by_name(&tmpl);
> +
> + return probe;
> +}
> +
> +/*
> + * Attach the given BPF program (identified by its file descriptor) to the
> + * kprobe identified by the given section name.
> + */
> +static int fbt_attach(const char *name, int bpf_fd)
> +{
> + char efn[256];
> + char buf[256];
> + int event_id, fd, rc;
> +
> + name += 7; /* skip "kprobe/" */
> + snprintf(buf, sizeof(buf), "p:%s %s\n", name, name);
> +
> + /*
> + * Register the kprobe with the tracing subsystem. This will create
> + * a tracepoint event.
> + */
> + fd = open(KPROBE_EVENTS, O_WRONLY | O_APPEND);
> + if (fd < 0) {
> + perror(KPROBE_EVENTS);
> + return -1;
> + }
> + rc = write(fd, buf, strlen(buf));
> + if (rc < 0) {
> + perror(KPROBE_EVENTS);
> + close(fd);
> + return -1;
> + }
> + close(fd);
> +
> + /*
> + * Read the tracepoint event id for the kprobe we just registered.
> + */
> + strcpy(efn, EVENTSFS);
> + strcat(efn, "kprobes/");
> + strcat(efn, name);
> + strcat(efn, "/id");
> +
> + fd = open(efn, O_RDONLY);
> + if (fd < 0) {
> + perror(efn);
> + return -1;
> + }
> + rc = read(fd, buf, sizeof(buf));
> + if (rc < 0 || rc >= sizeof(buf)) {
> + perror(efn);
> + close(fd);
> + return -1;
> + }
> + close(fd);
> + buf[rc] = '\0';
> + event_id = atoi(buf);
> +
> + /*
> + * Attaching a BPF program (by file descriptor) to an event (by ID) is
> + * a generic operation provided by the BPF interface code.
> + */
> + return dt_bpf_attach(event_id, bpf_fd);
> +}
> +
> +struct dt_provider dt_fbt = {
> + .name = "fbt",
> + .populate = &fbt_populate,
> + .resolve_event = &fbt_resolve_event,
> + .attach = &fbt_attach,
> +};
> diff --git a/tools/dtrace/dt_hash.c b/tools/dtrace/dt_hash.c
> new file mode 100644
> index 000000000000..b1f563bc0773
> --- /dev/null
> +++ b/tools/dtrace/dt_hash.c
> @@ -0,0 +1,211 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * This file provides a generic hashtable implementation for probes.
> + *
> + * The hashtable is created with 4 user-provided functions:
> + * hval(probe) - calculate a hash value for the given probe
> + * cmp(probe1, probe2) - compare two probes
> + * add(head, probe) - add a probe to a list of probes
> + * del(head, probe) - delete a probe from a list of probes
> + *
> + * Probes are hashed into a hashtable slot based on the return value of
> + * hval(probe). Each hashtable slot holds a list of buckets, with each
> + * bucket storing probes that are equal under the cmp(probe1, probe2)
> + * function. Probes are added to the list of probes in a bucket using the
> + * add(head, probe) function, and they are deleted using a call to the
> + * del(head, probe) function.
> + *
> + * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
> + */
> +#include <errno.h>
> +#include <stdint.h>
> +#include <stdlib.h>
> +
> +#include "dtrace_impl.h"
> +
> +/*
> + * Hashtable implementation for probes.
> + */
> +struct dt_hbucket {
> + u32 hval;
> + struct dt_hbucket *next;
> + struct dt_probe *head;
> + int nprobes;
> +};
> +
> +struct dt_htab {
> + struct dt_hbucket **tab;
> + int size;
> + int mask;
> + int nbuckets;
> + dt_hval_fn hval; /* calculate hash value */
> + dt_cmp_fn cmp; /* compare 2 probes */
> + dt_add_fn add; /* add probe to list */
> + dt_del_fn del; /* delete probe from list */
> +};
> +
> +/*
> + * Create a new (empty) hashtable.
> + */
> +struct dt_htab *dt_htab_new(dt_hval_fn hval, dt_cmp_fn cmp, dt_add_fn add,
> + dt_del_fn del)
> +{
> + struct dt_htab *htab = malloc(sizeof(struct dt_htab));
> +
> + if (!htab)
> + return NULL;
> +
> + htab->size = 1;
> + htab->mask = htab->size - 1;
> + htab->nbuckets = 0;
> + htab->hval = hval;
> + htab->cmp = cmp;
> + htab->add = add;
> + htab->del = del;
> +
> + htab->tab = calloc(htab->size, sizeof(struct dt_hbucket *));
> + if (!htab->tab) {
> + free(htab);
> + return NULL;
> + }
> +
> + return htab;
> +}
> +
> +/*
> + * Resize the hashtable by doubling the number of slots.
> + */
> +static int resize(struct dt_htab *htab)
> +{
> + int i;
> + int osize = htab->size;
> + int nsize = osize << 1;
> + int nmask = nsize - 1;
> + struct dt_hbucket **ntab;
> +
> + ntab = calloc(nsize, sizeof(struct dt_hbucket *));
> + if (!ntab)
> + return -ENOMEM;
> +
> + for (i = 0; i < osize; i++) {
> + struct dt_hbucket *bucket, *next;
> +
> + for (bucket = htab->tab[i]; bucket; bucket = next) {
> + int idx = bucket->hval & nmask;
> +
> + next = bucket->next;
> + bucket->next = ntab[idx];
> + ntab[idx] = bucket;
> + }
> + }
> +
> + free(htab->tab);
> + htab->tab = ntab;
> + htab->size = nsize;
> + htab->mask = nmask;
> +
> + return 0;
> +}
> +
> +/*
> + * Add a probe to the hashtable. Resize if necessary, and allocate a new
> + * bucket if necessary.
> + */
> +int dt_htab_add(struct dt_htab *htab, struct dt_probe *probe)
> +{
> + u32 hval = htab->hval(probe);
> + int idx;
> + struct dt_hbucket *bucket;
> +
> +retry:
> + idx = hval & htab->mask;
> + for (bucket = htab->tab[idx]; bucket; bucket = bucket->next) {
> + if (htab->cmp(bucket->head, probe) == 0)
> + goto add;
> + }
> +
> + if ((htab->nbuckets >> 1) > htab->size) {
> + int err;
> +
> + err = resize(htab);
> + if (err)
> + return err;
> +
> + goto retry;
> + }
> +
> + bucket = malloc(sizeof(struct dt_hbucket));
> + if (!bucket)
> + return -ENOMEM;
> +
> + bucket->hval = hval;
> + bucket->next = htab->tab[idx];
> + bucket->head = NULL;
> + bucket->nprobes = 0;
> + htab->tab[idx] = bucket;
> + htab->nbuckets++;
> +
> +add:
> + bucket->head = htab->add(bucket->head, probe);
> + bucket->nprobes++;
> +
> + return 0;
> +}
> +
> +/*
> + * Find a probe in the hashtable.
> + */
> +struct dt_probe *dt_htab_lookup(const struct dt_htab *htab,
> + const struct dt_probe *probe)
> +{
> + u32 hval = htab->hval(probe);
> + int idx = hval & htab->mask;
> + struct dt_hbucket *bucket;
> +
> + for (bucket = htab->tab[idx]; bucket; bucket = bucket->next) {
> + if (htab->cmp(bucket->head, probe) == 0)
> + return bucket->head;
> + }
> +
> + return NULL;
> +}
> +
> +/*
> + * Remove a probe from the hashtable. If we are deleting the last probe in a
> + * bucket, get rid of the bucket.
> + */
> +int dt_htab_del(struct dt_htab *htab, struct dt_probe *probe)
> +{
> + u32 hval = htab->hval(probe);
> + int idx = hval & htab->mask;
> + struct dt_hbucket *bucket;
> + struct dt_probe *head;
> +
> + for (bucket = htab->tab[idx]; bucket; bucket = bucket->next) {
> + if (htab->cmp(bucket->head, probe) == 0)
> + break;
> + }
> +
> + if (bucket == NULL)
> + return -ENOENT;
> +
> + head = htab->del(bucket->head, probe);
> + if (!head) {
> + struct dt_hbucket *b = htab->tab[idx];
> +
> + if (bucket == b)
> + htab->tab[idx] = bucket->next;
> + else {
> + while (b->next != bucket)
> + b = b->next;
> +
> + b->next = bucket->next;
> + }
> +
> + htab->nbuckets--;
> + free(bucket);
> + } else
> + bucket->head = head;
> +
> + return 0;
> +}
> diff --git a/tools/dtrace/dt_probe.c b/tools/dtrace/dt_probe.c
> new file mode 100644
> index 000000000000..0b6228eaff29
> --- /dev/null
> +++ b/tools/dtrace/dt_probe.c
> @@ -0,0 +1,230 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * This file implements the interface to probes grouped by provider.
> + *
> + * Probes are named by a set of 4 identifiers:
> + * - provider name
> + * - module name
> + * - function name
> + * - probe name
> + *
> + * The Fully Qualified Name (FQN) is "provider:module:function:name".
> + *
> + * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
> + */
> +#include <errno.h>
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include <string.h>
> +#include <linux/bpf.h>
> +#include <linux/kernel.h>
> +
> +#include "dtrace_impl.h"
> +
> +static struct dt_provider *dt_providers[] = {
> + &dt_fbt,
> + &dt_syscall,
> + };
> +
> +static struct dt_htab *ht_byfqn;
> +
> +static u32 next_probe_id;
> +
> +/*
> + * Calculate a hash value based on a given string and an initial value. The
> + * initial value is used to calculate compound hash values, e.g.
> + *
> + * u32 hval;
> + *
> + * hval = str2hval(str1, 0);
> + * hval = str2hval(str2, hval);
> + */
> +static u32 str2hval(const char *p, u32 hval)
> +{
> + u32 g;
> +
> + if (!p)
> + return hval;
> +
> + while (*p) {
> + hval = (hval << 4) + *p++;
> + g = hval & 0xf0000000;
> + if (g != 0)
> + hval ^= g >> 24;
> +
> + hval &= ~g;
> + }
> +
> + return hval;
> +}
> +
> +/*
> + * String compare function that can handle either or both strings being NULL.
> + */
> +static int safe_strcmp(const char *p, const char *q)
> +{
> + return (!p) ? (!q) ? 0
> + : -1
> + : (!q) ? 1
> + : strcmp(p, q);
> +}
> +
> +/*
> + * Calculate the hash value of a probe as the cummulative hash value of the
> + * FQN.
> + */
> +static u32 fqn_hval(const struct dt_probe *probe)
> +{
> + u32 hval = 0;
> +
> + hval = str2hval(probe->prv_name, hval);
> + hval = str2hval(":", hval);
> + hval = str2hval(probe->mod_name, hval);
> + hval = str2hval(":", hval);
> + hval = str2hval(probe->fun_name, hval);
> + hval = str2hval(":", hval);
> + hval = str2hval(probe->prb_name, hval);
> +
> + return hval;
> +}
> +
> +/*
> + * Compare two probes based on the FQN.
> + */
> +static int fqn_cmp(const struct dt_probe *p, const struct dt_probe *q)
> +{
> + int rc;
> +
> + rc = safe_strcmp(p->prv_name, q->prv_name);
> + if (rc)
> + return rc;
> + rc = safe_strcmp(p->mod_name, q->mod_name);
> + if (rc)
> + return rc;
> + rc = safe_strcmp(p->fun_name, q->fun_name);
> + if (rc)
> + return rc;
> + rc = safe_strcmp(p->prb_name, q->prb_name);
> + if (rc)
> + return rc;
> +
> + return 0;
> +}
> +
> +/*
> + * Add the given probe 'new' to the double-linked probe list 'head'. Probe
> + * 'new' becomes the new list head.
> + */
> +static struct dt_probe *fqn_add(struct dt_probe *head, struct dt_probe *new)
> +{
> + if (!head)
> + return new;
> +
> + new->he_fqn.next = head;
> + head->he_fqn.prev = new;
> +
> + return new;
> +}
> +
> +/*
> + * Remove the given probe 'probe' from the double-linked probe list 'head'.
> + * If we are deleting the current head, the next probe in the list is returned
> + * as the new head. If that value is NULL, the list is now empty.
> + */
> +static struct dt_probe *fqn_del(struct dt_probe *head, struct dt_probe *probe)
> +{
> + if (head == probe) {
> + if (!probe->he_fqn.next)
> + return NULL;
> +
> + head = probe->he_fqn.next;
> + head->he_fqn.prev = NULL;
> + probe->he_fqn.next = NULL;
> +
> + return head;
> + }
> +
> + if (!probe->he_fqn.next) {
> + probe->he_fqn.prev->he_fqn.next = NULL;
> + probe->he_fqn.prev = NULL;
> +
> + return head;
> + }
> +
> + probe->he_fqn.prev->he_fqn.next = probe->he_fqn.next;
> + probe->he_fqn.next->he_fqn.prev = probe->he_fqn.prev;
> + probe->he_fqn.prev = probe->he_fqn.next = NULL;
> +
> + return head;
> +}
> +
> +/*
> + * Initialize the probe handling by populating the FQN hashtable with probes
> + * from all providers.
> + */
> +int dt_probe_init(void)
> +{
> + int i;
> +
> + ht_byfqn = dt_htab_new(fqn_hval, fqn_cmp, fqn_add, fqn_del);
> +
> + for (i = 0; i < ARRAY_SIZE(dt_providers); i++) {
> + if (dt_providers[i]->populate() < 0)
> + return -1;
> + }
> +
> + return 0;
> +}
> +
> +/*
> + * Allocate a new probe and add it to the FQN hashtable.
> + */
> +int dt_probe_new(const struct dt_provider *prov, const char *pname,
> + const char *mname, const char *fname, const char *name)
> +{
> + struct dt_probe *probe;
> +
> + probe = malloc(sizeof(struct dt_probe));
> + if (!probe)
> + return -ENOMEM;
> +
> + memset(probe, 0, sizeof(struct dt_probe));
> + probe->id = next_probe_id++;
> + probe->prov = prov;
> + probe->prv_name = pname ? strdup(pname) : NULL;
> + probe->mod_name = mname ? strdup(mname) : NULL;
> + probe->fun_name = fname ? strdup(fname) : NULL;
> + probe->prb_name = name ? strdup(name) : NULL;
> +
> + dt_htab_add(ht_byfqn, probe);
> +
> + return 0;
> +}
> +
> +/*
> + * Perform a probe lookup based on FQN.
> + */
> +struct dt_probe *dt_probe_by_name(const struct dt_probe *tmpl)
> +{
> + return dt_htab_lookup(ht_byfqn, tmpl);
> +}
> +
> +/*
> + * Resolve an event name (BPF ELF section name) into a probe. We query each
> + * provider, and as soon as we get a hit, we return the result.
> + */
> +struct dt_probe *dt_probe_resolve_event(const char *name)
> +{
> + int i;
> + struct dt_probe *probe;
> +
> + for (i = 0; i < ARRAY_SIZE(dt_providers); i++) {
> + if (!dt_providers[i]->resolve_event)
> + continue;
> + probe = dt_providers[i]->resolve_event(name);
> + if (probe)
> + return probe;
> + }
> +
> + return NULL;
> +}
> diff --git a/tools/dtrace/dt_syscall.c b/tools/dtrace/dt_syscall.c
> new file mode 100644
> index 000000000000..6695a4a1c701
> --- /dev/null
> +++ b/tools/dtrace/dt_syscall.c
> @@ -0,0 +1,179 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * The syscall provider for DTrace.
> + *
> + * System call probes are exposed by the kernel as tracepoint events in the
> + * "syscalls" group. Entry probe names start with "sys_enter_" and exit probes
> + * start with "sys_exit_".
> + *
> + * Mapping from event name to DTrace probe name:
> + *
> + * syscalls:sys_enter_<name> syscall:vmlinux:<name>:entry
> + * syscalls:sys_exit_<name> syscall:vmlinux:<name>:return
> + *
> + * Mapping from BPF section name to DTrace probe name:
> + *
> + * tracepoint/syscalls/sys_enter_<name> syscall:vmlinux:<name>:entry
> + * tracepoint/syscalls/sys_exit_<name> syscall:vmlinux:<name>:return
> + *
> + * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
> + */
> +#include <ctype.h>
> +#include <fcntl.h>
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include <string.h>
> +#include <unistd.h>
> +#include <linux/bpf.h>
> +#include <sys/stat.h>
> +#include <sys/types.h>
> +
> +#include "dtrace_impl.h"
> +
> +static const char provname[] = "syscall";
> +static const char modname[] = "vmlinux";
> +
> +#define PROBE_LIST TRACEFS "available_events"
> +
> +#define PROV_PREFIX "syscalls:"
> +#define ENTRY_PREFIX "sys_enter_"
> +#define EXIT_PREFIX "sys_exit_"
> +
> +/*
> + * Scan the PROBE_LIST file and add probes for any syscalls events.
> + */
> +static int syscall_populate(void)
> +{
> + FILE *f;
> + char buf[256];
> +
> + f = fopen(PROBE_LIST, "r");
> + if (f == NULL)
> + return -1;
> +
> + while (fgets(buf, sizeof(buf), f)) {
> + char *p;
> +
> + /* * Here buf is "group:event". */
> + p = strchr(buf, '\n');
> + if (p)
> + *p = '\0';
> + else {
> + /*
> + * If we didn't see a newline, the line was too long.
> + * Report it, and continue until the end of the line.
> + */
> + fprintf(stderr, "%s: Line too long: %s\n",
> + PROBE_LIST, buf);
> + do
> + fgets(buf, sizeof(buf), f);
> + while (strchr(buf, '\n') == NULL);
> + continue;
> + }
> +
> + /* We need "group:" to match "syscalls:". */
> + p = buf;
> + if (memcmp(p, PROV_PREFIX, sizeof(PROV_PREFIX) - 1) != 0)
> + continue;
> +
> + p += sizeof(PROV_PREFIX) - 1;
> + /*
> + * Now p will be just "event", and we are only interested in
> + * events that match "sys_enter_*" or "sys_exit_*".
> + */
> + if (!memcmp(p, ENTRY_PREFIX, sizeof(ENTRY_PREFIX) - 1)) {
> + p += sizeof(ENTRY_PREFIX) - 1;
> + dt_probe_new(&dt_syscall, provname, modname, p,
> + "entry");
> + } else if (!memcmp(p, EXIT_PREFIX, sizeof(EXIT_PREFIX) - 1)) {
> + p += sizeof(EXIT_PREFIX) - 1;
> + dt_probe_new(&dt_syscall, provname, modname, p,
> + "return");
> + }
> + }
> +
> + fclose(f);
> +
> + return 0;
> +}
> +
> +#define EVENT_PREFIX "tracepoint/syscalls/"
> +
> +/*
> + * Perform a probe lookup based on an event name (BPF ELF section name).
> + */
> +static struct dt_probe *systrace_resolve_event(const char *name)
> +{
> + const char *prbname;
> + struct dt_probe tmpl;
> + struct dt_probe *probe;
> +
> + if (!name)
> + return NULL;
> +
> + /* Exclude anything that is not a syscalls tracepoint */
> + if (strncmp(name, EVENT_PREFIX, sizeof(EVENT_PREFIX) - 1) != 0)
> + return NULL;
> + name += sizeof(EVENT_PREFIX) - 1;
> +
> + if (strncmp(name, ENTRY_PREFIX, sizeof(ENTRY_PREFIX) - 1) == 0) {
> + name += sizeof(ENTRY_PREFIX) - 1;
> + prbname = "entry";
> + } else if (strncmp(name, EXIT_PREFIX, sizeof(EXIT_PREFIX) - 1) == 0) {
> + name += sizeof(EXIT_PREFIX) - 1;
> + prbname = "return";
> + } else
> + return NULL;
> +
> + memset(&tmpl, 0, sizeof(tmpl));
> + tmpl.prv_name = provname;
> + tmpl.mod_name = modname;
> + tmpl.fun_name = name;
> + tmpl.prb_name = prbname;
> +
> + probe = dt_probe_by_name(&tmpl);
> +
> + return probe;
> +}
> +
> +#define SYSCALLSFS EVENTSFS "syscalls/"
> +
> +/*
> + * Attach the given BPF program (identified by its file descriptor) to the
> + * event identified by the given section name.
> + */
> +static int syscall_attach(const char *name, int bpf_fd)
> +{
> + char efn[256];
> + char buf[256];
> + int event_id, fd, rc;
> +
> + name += sizeof(EVENT_PREFIX) - 1;
> + strcpy(efn, SYSCALLSFS);
> + strcat(efn, name);
> + strcat(efn, "/id");
> +
> + fd = open(efn, O_RDONLY);
> + if (fd < 0) {
> + perror(efn);
> + return -1;
> + }
> + rc = read(fd, buf, sizeof(buf));
> + if (rc < 0 || rc >= sizeof(buf)) {
> + perror(efn);
> + close(fd);
> + return -1;
> + }
> + close(fd);
> + buf[rc] = '\0';
> + event_id = atoi(buf);
> +
> + return dt_bpf_attach(event_id, bpf_fd);
> +}
> +
> +struct dt_provider dt_syscall = {
> + .name = "syscall",
> + .populate = &syscall_populate,
> + .resolve_event = &systrace_resolve_event,
> + .attach = &syscall_attach,
> +};
> diff --git a/tools/dtrace/dt_utils.c b/tools/dtrace/dt_utils.c
> new file mode 100644
> index 000000000000..55d51bae1d97
> --- /dev/null
> +++ b/tools/dtrace/dt_utils.c
> @@ -0,0 +1,132 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
> + */
> +#include <sys/types.h>
> +#include <sys/stat.h>
> +#include <fcntl.h>
> +#include <stdlib.h>
> +#include <string.h>
> +#include <unistd.h>
> +
> +#include "dtrace_impl.h"
> +
> +#define BUF_SIZE 1024 /* max size for online cpu data */
> +
> +int dt_numcpus; /* number of online CPUs */
> +int dt_maxcpuid; /* highest CPU id */
> +int *dt_cpuids; /* list of CPU ids */
> +
> +/*
> + * Populate the online CPU id information from sysfs data. We only do this
> + * once because we do not care about CPUs coming online after we started
> + * tracing. If a CPU goes offline during tracing, we do not care either
> + * because that simply means that it won't be writing any new probe data into
> + * its buffer.
> + */
> +void cpu_list_populate(void)
> +{
> + char buf[BUF_SIZE];
> + int fd, cnt, start, end, i;
> + int *cpu;
> + char *p, *q;
> +
> + fd = open("/sys/devices/system/cpu/online", O_RDONLY);
> + if (fd < 0)
> + goto fail;
> + cnt = read(fd, buf, sizeof(buf));
> + close(fd);
> + if (cnt <= 0)
> + goto fail;
> +
> + /*
> + * The string should always end with a newline, but let's make sure.
> + */
> + if (buf[cnt - 1] == '\n')
> + buf[--cnt] = 0;
> +
> + /*
> + * Count how many CPUs we have.
> + */
> + dt_numcpus = 0;
> + p = buf;
> + do {
> + start = (int)strtol(p, &q, 10);
> + switch (*q) {
> + case '-': /* range */
> + p = q + 1;
> + end = (int)strtol(p, &q, 10);
> + dt_numcpus += end - start + 1;
> + if (*q == 0) { /* end of string */
> + p = q;
> + break;
> + }
> + if (*q != ',')
> + goto fail;
> + p = q + 1;
> + break;
> + case 0: /* end of string */
> + dt_numcpus++;
> + p = q;
> + break;
> + case ',': /* gap */
> + dt_numcpus++;
> + p = q + 1;
> + break;
> + }
> + } while (*p != 0);
> +
> + dt_cpuids = calloc(dt_numcpus, sizeof(int));
> + cpu = dt_cpuids;
> +
> + /*
> + * Fill in the CPU ids.
> + */
> + p = buf;
> + do {
> + start = (int)strtol(p, &q, 10);
> + switch (*q) {
> + case '-': /* range */
> + p = q + 1;
> + end = (int)strtol(p, &q, 10);
> + for (i = start; i <= end; i++)
> + *cpu++ = i;
> + if (*q == 0) { /* end of string */
> + p = q;
> + break;
> + }
> + if (*q != ',')
> + goto fail;
> + p = q + 1;
> + break;
> + case 0: /* end of string */
> + *cpu = start;
> + p = q;
> + break;
> + case ',': /* gap */
> + *cpu++ = start;
> + p = q + 1;
> + break;
> + }
> + } while (*p != 0);
> +
> + /* Record the highest CPU id of the set of online CPUs. */
> + dt_maxcpuid = *(cpu - 1);
> +
> + return;
> +fail:
> + if (dt_cpuids)
> + free(dt_cpuids);
> +
> + dt_numcpus = 0;
> + dt_maxcpuid = 0;
> + dt_cpuids = NULL;
> +}
> +
> +void cpu_list_free(void)
> +{
> + free(dt_cpuids);
> + dt_numcpus = 0;
> + dt_maxcpuid = 0;
> + dt_cpuids = NULL;
> +}
> diff --git a/tools/dtrace/dtrace.c b/tools/dtrace/dtrace.c
> new file mode 100644
> index 000000000000..36ad526c1cd4
> --- /dev/null
> +++ b/tools/dtrace/dtrace.c
> @@ -0,0 +1,249 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
> + */
> +#include <errno.h>
> +#include <libgen.h>
> +#include <stdarg.h>
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include <string.h>
> +#include <unistd.h>
> +#include <linux/log2.h>
> +
> +#include "dtrace_impl.h"
> +
> +#define DTRACE_BUFSIZE 32 /* default buffer size (in pages) */
> +
> +#define DMODE_VERS 0 /* display version information (-V) */
> +#define DMODE_LIST 1 /* list probes (-l) */
> +#define DMODE_EXEC 2 /* compile program and start tracing */
> +
> +#define E_SUCCESS 0
> +#define E_ERROR 1
> +#define E_USAGE 2
> +
> +#define NUM_PAGES(sz) (((sz) + getpagesize() - 1) / getpagesize())
> +
> +static const char *dtrace_options = "+b:ls:V";
> +
> +static char *g_pname;
> +static int g_mode = DMODE_EXEC;
> +
> +static int usage(void)
> +{
> + fprintf(stderr, "Usage: %s [-lV] [-b bufsz] -s script\n", g_pname);
> + fprintf(stderr,
> + "\t-b set trace buffer size\n"
> + "\t-l list probes matching specified criteria\n"
> + "\t-s enable or list probes for the specified BPF program\n"
> + "\t-V report DTrace API version\n");
> +
> + return E_USAGE;
> +}
> +
> +static u64 parse_size(const char *arg)
> +{
> + long long mul = 1;
> + long long neg, val;
> + size_t len;
> + char *end;
> +
> + if (!arg)
> + return -1;
> +
> + len = strlen(arg);
> + if (!len)
> + return -1;
> +
> + switch (arg[len - 1]) {
> + case 't':
> + case 'T':
> + mul *= 1024;
> + /* fall-through */
> + case 'g':
> + case 'G':
> + mul *= 1024;
> + /* fall-through */
> + case 'm':
> + case 'M':
> + mul *= 1024;
> + /* fall-through */
> + case 'k':
> + case 'K':
> + mul *= 1024;
> + /* fall-through */
> + default:
> + break;
> + }
> +
> + neg = strtoll(arg, NULL, 0);
> + errno = 0;
> + val = strtoull(arg, &end, 0) * mul;
> +
> + if ((mul > 1 && end != &arg[len - 1]) || (mul == 1 && *end != '\0') ||
> + val < 0 || neg < 0 || errno != 0)
> + return -1;
> +
> + return val;
> +}
> +
> +int main(int argc, char *argv[])
> +{
> + int i;
> + int modec = 0;
> + int bufsize = DTRACE_BUFSIZE;
> + int epoll_fd;
> + int cnt;
> + char **prgv;
> + int prgc;
> +
> + g_pname = basename(argv[0]);
> +
> + if (argc == 1)
> + return usage();
> +
> + prgc = 0;
> + prgv = calloc(argc, sizeof(char *));
> + if (!prgv) {
> + fprintf(stderr, "failed to allocate memory for arguments: %s\n",
> + strerror(errno));
> + return E_ERROR;
> + }
> +
> + argv[0] = g_pname; /* argv[0] for getopt errors */
> +
> + for (optind = 1; optind < argc; optind++) {
> + int opt;
> +
> + while ((opt = getopt(argc, argv, dtrace_options)) != EOF) {
> + u64 val;
> +
> + switch (opt) {
> + case 'b':
> + val = parse_size(optarg);
> + if (val < 0) {
> + fprintf(stderr, "invalid: -b %s\n",
> + optarg);
> + return E_ERROR;
> + }
> +
> + /*
> + * Bufsize needs to be a number of pages, and
> + * must be a power of 2. This is required by
> + * the perf event buffer code.
> + */
> + bufsize = roundup_pow_of_two(NUM_PAGES(val));
> + if ((u64)bufsize * getpagesize() > val)
> + fprintf(stderr,
> + "bufsize increased to %ld\n",
> + (u64)bufsize * getpagesize());
> +
> + break;
> + case 'l':
> + g_mode = DMODE_LIST;
> + modec++;
> + break;
> + case 's':
> + prgv[prgc++] = optarg;
> + break;
> + case 'V':
> + g_mode = DMODE_VERS;
> + modec++;
> + break;
> + default:
> + if (strchr(dtrace_options, opt) == NULL)
> + return usage();
> + }
> + }
> +
> + if (optind < argc) {
> + fprintf(stderr, "unknown option '%s'\n", argv[optind]);
> + return E_ERROR;
> + }
> + }
> +
> + if (modec > 1) {
> + fprintf(stderr,
> + "only one of [-lV] can be specified at a time\n");
> + return E_USAGE;
> + }
> +
> + /*
> + * We handle requests for version information first because we do not
> + * need probe information for it.
> + */
> + if (g_mode == DMODE_VERS) {
> + printf("%s\n"
> + "This is DTrace %s\n"
> + "dtrace(1) version-control ID: %s\n",
> + DT_VERS_STRING, DT_VERSION, DT_GIT_VERSION);
> +
> + return E_SUCCESS;
> + }
> +
> + /* Initialize probes. */
> + if (dt_probe_init() < 0) {
> + fprintf(stderr, "failed to initialize probes: %s\n",
> + strerror(errno));
> + return E_ERROR;
> + }
> +
> + /*
> + * We handle requests to list probes next.
> + */
> + if (g_mode == DMODE_LIST) {
> + int rc = 0;
> +
> + printf("%5s %10s %17s %33s %s\n",
> + "ID", "PROVIDER", "MODULE", "FUNCTION", "NAME");
> + for (i = 0; i < prgc; i++) {
> + rc = dt_bpf_list_probes(prgv[i]);
> + if (rc < 0)
> + fprintf(stderr, "failed to load %s: %s\n",
> + prgv[i], strerror(errno));
> + }
> +
> + return rc ? E_ERROR : E_SUCCESS;
> + }
> +
> + if (!prgc) {
> + fprintf(stderr, "missing BPF program(s)\n");
> + return E_ERROR;
> + }
> +
> + /* Process the BPF program. */
> + for (i = 0; i < prgc; i++) {
> + int err;
> +
> + err = dt_bpf_load_file(prgv[i]);
> + if (err) {
> + errno = -err;
> + fprintf(stderr, "failed to load %s: %s\n",
> + prgv[i], strerror(errno));
> + return E_ERROR;
> + }
> + }
> +
> + /* Get the list of online CPUs. */
> + cpu_list_populate();
> +
> + /* Initialize buffers. */
> + epoll_fd = dt_buffer_init(bufsize);
> + if (epoll_fd < 0) {
> + errno = -epoll_fd;
> + fprintf(stderr, "failed to allocate buffers: %s\n",
> + strerror(errno));
> + return E_ERROR;
> + }
> +
> + /* Process probe data. */
> + printf("%3s %6s\n", "CPU", "ID");
> + do {
> + cnt = dt_buffer_poll(epoll_fd, 100);
> + } while (cnt >= 0);
> +
> + dt_buffer_exit(epoll_fd);
> +
> + return E_SUCCESS;
> +}
> diff --git a/tools/dtrace/dtrace.h b/tools/dtrace/dtrace.h
> new file mode 100644
> index 000000000000..c79398432d17
> --- /dev/null
> +++ b/tools/dtrace/dtrace.h
> @@ -0,0 +1,13 @@
> +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
> +/*
> + * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
> + */
> +#ifndef _UAPI_LINUX_DTRACE_H
> +#define _UAPI_LINUX_DTRACE_H
> +
> +struct dt_bpf_context {
> + u32 probe_id;
> + u64 argv[10];
> +};
> +
> +#endif /* _UAPI_LINUX_DTRACE_H */
> diff --git a/tools/dtrace/dtrace_impl.h b/tools/dtrace/dtrace_impl.h
> new file mode 100644
> index 000000000000..9aa51b4c4aee
> --- /dev/null
> +++ b/tools/dtrace/dtrace_impl.h
> @@ -0,0 +1,101 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
> + */
> +#ifndef _DTRACE_H
> +#define _DTRACE_H
> +
> +#include <unistd.h>
> +#include <bpf/libbpf.h>
> +#include <linux/types.h>
> +#include <linux/ptrace.h>
> +#include <linux/perf_event.h>
> +#include <sys/syscall.h>
> +
> +#include "dtrace.h"
> +
> +#define DT_DEBUG
> +
> +#define DT_VERS_STRING "Oracle D 2.0.0"
> +
> +#define TRACEFS "/sys/kernel/debug/tracing/"
> +#define EVENTSFS TRACEFS "events/"
> +
> +extern int dt_numcpus;
> +extern int dt_maxcpuid;
> +extern int *dt_cpuids;
> +
> +extern void cpu_list_populate(void);
> +extern void cpu_list_free(void);
> +
> +struct dt_provider {
> + char *name;
> + int (*populate)(void);
> + struct dt_probe *(*resolve_event)(const char *name);
> + int (*attach)(const char *name, int bpf_fd);
> +};
> +
> +extern struct dt_provider dt_fbt;
> +extern struct dt_provider dt_syscall;
> +
> +struct dt_hentry {
> + struct dt_probe *next;
> + struct dt_probe *prev;
> +};
> +
> +struct dt_htab;
> +
> +typedef u32 (*dt_hval_fn)(const struct dt_probe *);
> +typedef int (*dt_cmp_fn)(const struct dt_probe *, const struct dt_probe *);
> +typedef struct dt_probe *(*dt_add_fn)(struct dt_probe *, struct dt_probe *);
> +typedef struct dt_probe *(*dt_del_fn)(struct dt_probe *, struct dt_probe *);
> +
> +extern struct dt_htab *dt_htab_new(dt_hval_fn hval, dt_cmp_fn cmp,
> + dt_add_fn add, dt_del_fn del);
> +extern int dt_htab_add(struct dt_htab *htab, struct dt_probe *probe);
> +extern struct dt_probe *dt_htab_lookup(const struct dt_htab *htab,
> + const struct dt_probe *probe);
> +extern int dt_htab_del(struct dt_htab *htab, struct dt_probe *probe);
> +
> +struct dt_probe {
> + u32 id;
> + int event_fd;
> + const struct dt_provider *prov;
> + const char *prv_name; /* provider name */
> + const char *mod_name; /* module name */
> + const char *fun_name; /* function name */
> + const char *prb_name; /* probe name */
> + struct dt_hentry he_fqn;
> +};
> +
> +typedef void (*dt_probe_fn)(const struct dt_probe *probe);
> +
> +extern int dt_probe_init(void);
> +extern int dt_probe_new(const struct dt_provider *prov, const char *pname,
> + const char *mname, const char *fname, const char *name);
> +extern struct dt_probe *dt_probe_by_name(const struct dt_probe *tmpl);
> +extern struct dt_probe *dt_probe_resolve_event(const char *name);
> +
> +extern int dt_bpf_list_probes(const char *fn);
> +extern int dt_bpf_load_file(const char *fn);
> +extern int dt_bpf_map_update(int fd, const void *key, const void *val);
> +extern int dt_bpf_attach(int event_id, int bpf_fd);
> +
> +extern int dt_bufmap_fd;
> +
> +extern int dt_buffer_init(int num_pages);
> +extern int dt_buffer_poll(int epoll_fd, int timeout);
> +extern void dt_buffer_exit(int epoll_fd);
> +
> +static inline int perf_event_open(struct perf_event_attr *attr, pid_t pid,
> + int cpu, int group_fd, unsigned long flags)
> +{
> + return syscall(__NR_perf_event_open, attr, pid, cpu, group_fd, flags);
> +}
> +
> +extern inline int bpf(enum bpf_cmd cmd, union bpf_attr *attr)
> +{
> + return syscall(__NR_bpf, cmd, attr, sizeof(union bpf_attr));
> +}
> +
> +#endif /* _DTRACE_H */
> --
> 2.20.1
^ permalink raw reply
* Re: [PATCH bpf-next v8 0/2] bpf: Allow bpf_skb_event_output for more prog types
From: Andrii Nakryiko @ 2019-07-10 18:05 UTC (permalink / raw)
To: Allan Zhang
Cc: Networking, bpf, Song Liu, Daniel Borkmann, Alexei Starovoitov
In-Reply-To: <20190709180005.33406-1-allanzhang@google.com>
On Tue, Jul 9, 2019 at 11:03 AM Allan Zhang <allanzhang@google.com> wrote:
>
> Software event output is only enabled by a few prog types right now (TC,
> LWT out, XDP, sockops). Many other skb based prog types need
> bpf_skb_event_output to produce software event.
>
> More prog types are enabled to access bpf_skb_event_output in this
> patch.
>
> v8 changes:
> No actual change, just cc to netdev@vger.kernel.org and
> bpf@vger.kernel.org.
> v7 patches are acked by Song Liu.
You forgot to include Song's Acked-by into your patch commit messages. Just add
Acked-by: Song Liu <songliubraving@fb.com>
to both patches after your Signed-off-by.
>
> v7 changes:
> Reformat from hints by scripts/checkpatch.pl, including Song's comment
> on signed-off-by name to captical case in cover letter.
> 3 of hints are ignored:
> 1. new file mode.
> 2. SPDX-License-Identifier for event_output.c since all files under
> this dir have no such line.
> 3. "Macros ... enclosed in parentheses" for macro in event_output.c
> due to code's nature.
>
> Change patch 02 subject "bpf:..." to "selftests/bpf:..."
>
> v6 changes:
> Fix Signed-off-by, fix fixup map creation.
>
> v5 changes:
> Fix typos, reformat comments in event_output.c, move revision history to
> cover letter.
>
> v4 changes:
> Reformating log message.
>
> v3 changes:
> Reformating log message.
>
> v2 changes:
> Reformating log message.
>
> Allan Zhang (2):
> bpf: Allow bpf_skb_event_output for a few prog types
> selftests/bpf: Add selftests for bpf_perf_event_output
>
> net/core/filter.c | 6 ++
> tools/testing/selftests/bpf/test_verifier.c | 12 ++-
> .../selftests/bpf/verifier/event_output.c | 94 +++++++++++++++++++
> 3 files changed, 111 insertions(+), 1 deletion(-)
> create mode 100644 tools/testing/selftests/bpf/verifier/event_output.c
>
> --
> 2.22.0.410.gd8fdbe21b5-goog
>
^ permalink raw reply
* [PATCH] net: phy: make exported variables non-static
From: Denis Efremov @ 2019-07-10 18:03 UTC (permalink / raw)
To: Andrew Lunn
Cc: Denis Efremov, Florian Fainelli, Heiner Kallweit, David S. Miller,
netdev, linux-kernel
The variables phy_basic_ports_array, phy_fibre_port_array and
phy_all_ports_features_array are declared static and marked
EXPORT_SYMBOL_GPL(), which is at best an odd combination.
Because the variables were decided to be a part of API, this commit
removes the static attributes and adds the declarations to the header.
Fixes: 3c1bcc8614db ("net: ethernet: Convert phydev advertize and supported from u32 to link mode")
Signed-off-by: Denis Efremov <efremov@linux.com>
---
drivers/net/phy/phy_device.c | 6 +++---
include/linux/phy.h | 3 +++
2 files changed, 6 insertions(+), 3 deletions(-)
diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index dcc93a873174..f94171e9aa45 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -56,19 +56,19 @@ EXPORT_SYMBOL_GPL(phy_10gbit_features);
__ETHTOOL_DECLARE_LINK_MODE_MASK(phy_10gbit_fec_features) __ro_after_init;
EXPORT_SYMBOL_GPL(phy_10gbit_fec_features);
-static const int phy_basic_ports_array[] = {
+const int phy_basic_ports_array[3] = {
ETHTOOL_LINK_MODE_Autoneg_BIT,
ETHTOOL_LINK_MODE_TP_BIT,
ETHTOOL_LINK_MODE_MII_BIT,
};
EXPORT_SYMBOL_GPL(phy_basic_ports_array);
-static const int phy_fibre_port_array[] = {
+const int phy_fibre_port_array[1] = {
ETHTOOL_LINK_MODE_FIBRE_BIT,
};
EXPORT_SYMBOL_GPL(phy_fibre_port_array);
-static const int phy_all_ports_features_array[] = {
+const int phy_all_ports_features_array[7] = {
ETHTOOL_LINK_MODE_Autoneg_BIT,
ETHTOOL_LINK_MODE_TP_BIT,
ETHTOOL_LINK_MODE_MII_BIT,
diff --git a/include/linux/phy.h b/include/linux/phy.h
index 6424586fe2d6..ec54a788fc96 100644
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -55,6 +55,9 @@ extern __ETHTOOL_DECLARE_LINK_MODE_MASK(phy_10gbit_full_features) __ro_after_ini
#define PHY_10GBIT_FEC_FEATURES ((unsigned long *)&phy_10gbit_fec_features)
#define PHY_10GBIT_FULL_FEATURES ((unsigned long *)&phy_10gbit_full_features)
+extern const int phy_basic_ports_array[3];
+extern const int phy_fibre_port_array[1];
+extern const int phy_all_ports_features_array[7];
extern const int phy_10_100_features_array[4];
extern const int phy_basic_t1_features_array[2];
extern const int phy_gbit_features_array[2];
--
2.21.0
^ permalink raw reply related
* [PATCH v6 bpf-next 0/3] bpf: add bpf_descendant_of helper
From: Javier Honduvilla Coto @ 2019-07-10 18:00 UTC (permalink / raw)
To: netdev; +Cc: yhs, kernel-team, jonhaslam
In-Reply-To: <20190410203631.1576576-1-javierhonduco@fb.com>
Hi all,
This patch adds the bpf_descendant_of helper which accepts a PID and
returns 1 if the PID of the process currently being executed is a
descendant of it or if it's itself. Returns 0 otherwise. The passed
PID should be the one as seen from the "global" pid namespace as the
processes' PIDs in the hierarchy are resolved using the context of said
initial namespace.
This is very useful in tracing programs when we want to filter by a
given PID and all the children it might spawn. The current workarounds
most people implement for this purpose have issues:
- Attaching to process spawning syscalls and dynamically add those PIDs
to some bpf map that would be used to filter is cumbersome and
potentially racy.
- Unrolling some loop to perform what this helper is doing consumes lots
of instructions. That and the impossibility to jump backwards makes it
really hard to be correct in really large process chains.
Let me know what do you think!
Thanks,
---
Changes in V6:
- Small style fix
- Clarify in the docs that we are resolving PIDs using the global,
initial PID namespace, and the provided *pid* argument should be global, too
- Changed the way we assert on the helper return value
Changes in V5:
- Addressed code review feedback
- Renamed from progenyof => descendant_of as suggested by Jon Haslam
and Brendan Gregg
Changes in V4:
- Rebased on latest bpf-next after merge window
Changes in V3:
- Removed RCU read (un)locking as BPF programs alredy run in RCU locked
context
- progenyof(0) now returns 1, which, semantically makes more sense
- Added new test case for PID 0 and changed sentinel value for errors
- Rebase on latest bpf-next/master
- Used my work email as somehow I accidentally used my personal one in v2
Changes in V2:
- Adding missing docs in include/uapi/linux/bpf.h
--
2.17.1
^ permalink raw reply
* [PATCH v6 bpf-next 3/3] bpf: add tests for bpf_descendant_of
From: Javier Honduvilla Coto @ 2019-07-10 18:00 UTC (permalink / raw)
To: netdev; +Cc: yhs, kernel-team, jonhaslam
In-Reply-To: <20190710180025.94726-1-javierhonduco@fb.com>
Adding the following test cases:
- bpf_descendant_of(current->pid) == 1
- bpf_descendant_of(current->real_parent->pid) == 1
- bpf_descendant_of(1) == 1
- bpf_descendant_of(0) == 1
- bpf_descendant_of(-1) == 0
- bpf_descendant_of(current->children[0]->pid) == 0
Signed-off-by: Javier Honduvilla Coto <javierhonduco@fb.com>
---
tools/testing/selftests/bpf/.gitignore | 1 +
tools/testing/selftests/bpf/Makefile | 2 +-
tools/testing/selftests/bpf/bpf_helpers.h | 3 +
.../bpf/progs/test_descendant_of_kern.c | 43 +++
.../selftests/bpf/test_descendant_of_user.c | 266 ++++++++++++++++++
5 files changed, 314 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/bpf/progs/test_descendant_of_kern.c
create mode 100644 tools/testing/selftests/bpf/test_descendant_of_user.c
diff --git a/tools/testing/selftests/bpf/.gitignore b/tools/testing/selftests/bpf/.gitignore
index 90f70d2c7c22..4b63d7105ba2 100644
--- a/tools/testing/selftests/bpf/.gitignore
+++ b/tools/testing/selftests/bpf/.gitignore
@@ -43,3 +43,4 @@ test_sockopt
test_sockopt_sk
test_sockopt_multi
test_tcp_rtt
+test_descendant_of_user
diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
index 2620406a53ec..b3dc1e26c41c 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -27,7 +27,7 @@ TEST_GEN_PROGS = test_verifier test_tag test_maps test_lru_map test_lpm_map test
test_cgroup_storage test_select_reuseport test_section_names \
test_netcnt test_tcpnotify_user test_sock_fields test_sysctl test_hashmap \
test_btf_dump test_cgroup_attach xdping test_sockopt test_sockopt_sk \
- test_sockopt_multi test_tcp_rtt
+ test_sockopt_multi test_tcp_rtt test_descendant_of_user
BPF_OBJ_FILES = $(patsubst %.c,%.o, $(notdir $(wildcard progs/*.c)))
TEST_GEN_FILES = $(BPF_OBJ_FILES)
diff --git a/tools/testing/selftests/bpf/bpf_helpers.h b/tools/testing/selftests/bpf/bpf_helpers.h
index 5a3d92c8bec8..7525783ffbc9 100644
--- a/tools/testing/selftests/bpf/bpf_helpers.h
+++ b/tools/testing/selftests/bpf/bpf_helpers.h
@@ -1,4 +1,6 @@
/* SPDX-License-Identifier: GPL-2.0 */
+#include <sys/types.h>
+
#ifndef __BPF_HELPERS_H
#define __BPF_HELPERS_H
@@ -228,6 +230,7 @@ static void *(*bpf_sk_storage_get)(void *map, struct bpf_sock *sk,
static int (*bpf_sk_storage_delete)(void *map, struct bpf_sock *sk) =
(void *)BPF_FUNC_sk_storage_delete;
static int (*bpf_send_signal)(unsigned sig) = (void *)BPF_FUNC_send_signal;
+static int (*bpf_descendant_of)(pid_t pid) = (void *) BPF_FUNC_descendant_of;
/* llvm builtin functions that eBPF C program may use to
* emit BPF_LD_ABS and BPF_LD_IND instructions
diff --git a/tools/testing/selftests/bpf/progs/test_descendant_of_kern.c b/tools/testing/selftests/bpf/progs/test_descendant_of_kern.c
new file mode 100644
index 000000000000..802e01595527
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/test_descendant_of_kern.c
@@ -0,0 +1,43 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/bpf.h>
+#include "bpf_helpers.h"
+
+struct bpf_map_def SEC("maps") pidmap = {
+ .type = BPF_MAP_TYPE_ARRAY,
+ .key_size = sizeof(__u32),
+ .value_size = sizeof(__u32),
+ .max_entries = 2,
+};
+
+struct bpf_map_def SEC("maps") resultmap = {
+ .type = BPF_MAP_TYPE_ARRAY,
+ .key_size = sizeof(__u32),
+ .value_size = sizeof(__u32),
+ .max_entries = 1,
+};
+
+SEC("tracepoint/syscalls/sys_enter_open")
+int trace(void *ctx)
+{
+ __u32 pid = bpf_get_current_pid_tgid();
+ __u32 current_key = 0, ancestor_key = 1, *expected_pid, *ancestor_pid;
+ __u32 *val;
+
+ expected_pid = bpf_map_lookup_elem(&pidmap, ¤t_key);
+ if (!expected_pid || *expected_pid != pid)
+ return 0;
+
+ ancestor_pid = bpf_map_lookup_elem(&pidmap, &ancestor_key);
+ if (!ancestor_pid)
+ return 0;
+
+ val = bpf_map_lookup_elem(&resultmap, ¤t_key);
+ if (val)
+ *val = bpf_descendant_of(*ancestor_pid);
+
+ return 0;
+}
+
+char _license[] SEC("license") = "GPL";
+__u32 _version SEC("version") = 1;
diff --git a/tools/testing/selftests/bpf/test_descendant_of_user.c b/tools/testing/selftests/bpf/test_descendant_of_user.c
new file mode 100644
index 000000000000..f616c8c976a4
--- /dev/null
+++ b/tools/testing/selftests/bpf/test_descendant_of_user.c
@@ -0,0 +1,266 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <syscall.h>
+#include <unistd.h>
+#include <linux/perf_event.h>
+#include <sys/ioctl.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+
+#include <bpf/bpf.h>
+#include <bpf/libbpf.h>
+
+#define CHECK(condition, tag, format...) \
+ ({ \
+ int __ret = !!(condition); \
+ if (__ret) { \
+ printf("%s:FAIL:%s ", __func__, tag); \
+ printf(format); \
+ } else { \
+ printf("%s:PASS:%s\n", __func__, tag); \
+ } \
+ __ret; \
+ })
+
+static int bpf_find_map(const char *test, struct bpf_object *obj,
+ const char *name)
+{
+ struct bpf_map *map;
+
+ map = bpf_object__find_map_by_name(obj, name);
+ if (!map)
+ return -1;
+ return bpf_map__fd(map);
+}
+
+int main(int argc, char **argv)
+{
+ const char *probe_name = "syscalls/sys_enter_open";
+ const char *file = "test_descendant_of_kern.o";
+ int err, bytes, efd, prog_fd, pmu_fd;
+ int resultmap_fd, pidmap_fd;
+ struct perf_event_attr attr = {};
+ struct bpf_object *obj;
+ __u32 descendant_of_result = 0;
+ __u32 key = 0, pid;
+ int exit_code = EXIT_FAILURE;
+ char buf[256];
+
+ int child_pid, ancestor_pid, root_fd, nonexistant = -42;
+ __u32 ancestor_key = 1;
+ int pipefd[2];
+ char marker[1];
+
+ err = bpf_prog_load(file, BPF_PROG_TYPE_TRACEPOINT, &obj, &prog_fd);
+ if (CHECK(err, "bpf_prog_load", "err %d errno %d\n", err, errno))
+ goto fail;
+
+ resultmap_fd = bpf_find_map(__func__, obj, "resultmap");
+ if (CHECK(resultmap_fd < 0, "bpf_find_map", "err %d errno %d\n",
+ resultmap_fd, errno))
+ goto close_prog;
+
+ pidmap_fd = bpf_find_map(__func__, obj, "pidmap");
+ if (CHECK(pidmap_fd < 0, "bpf_find_map", "err %d errno %d\n", pidmap_fd,
+ errno))
+ goto close_prog;
+
+ pid = getpid();
+ bpf_map_update_elem(pidmap_fd, &key, &pid, 0);
+ bpf_map_update_elem(pidmap_fd, &ancestor_key, &pid, 0);
+
+ snprintf(buf, sizeof(buf), "/sys/kernel/debug/tracing/events/%s/id",
+ probe_name);
+ efd = open(buf, O_RDONLY, 0);
+ if (CHECK(efd < 0, "open", "err %d errno %d\n", efd, errno))
+ goto close_prog;
+ bytes = read(efd, buf, sizeof(buf));
+ close(efd);
+ if (CHECK(bytes <= 0 || bytes >= sizeof(buf), "read",
+ "bytes %d errno %d\n", bytes, errno))
+ goto close_prog;
+
+ attr.config = strtol(buf, NULL, 0);
+ attr.type = PERF_TYPE_TRACEPOINT;
+ attr.sample_type = PERF_SAMPLE_RAW;
+ attr.sample_period = 1;
+ attr.wakeup_events = 1;
+
+ pmu_fd = syscall(__NR_perf_event_open, &attr, getpid(), -1, -1, 0);
+ if (CHECK(pmu_fd < 0, "perf_event_open", "err %d errno %d\n", pmu_fd,
+ errno))
+ goto close_prog;
+
+ err = ioctl(pmu_fd, PERF_EVENT_IOC_ENABLE, 0);
+ if (CHECK(err, "perf_event_ioc_enable", "err %d errno %d\n", err,
+ errno))
+ goto close_pmu;
+
+ err = ioctl(pmu_fd, PERF_EVENT_IOC_SET_BPF, prog_fd);
+ if (CHECK(err, "perf_event_ioc_set_bpf", "err %d errno %d\n", err,
+ errno))
+ goto close_pmu;
+
+ // Test that descendant_of(current->pid) is true
+ bpf_map_update_elem(pidmap_fd, &key, &pid, 0);
+ bpf_map_update_elem(pidmap_fd, &ancestor_key, &pid, 0);
+ bpf_map_update_elem(resultmap_fd, &key, &nonexistant, 0);
+
+ root_fd = open("/", O_RDONLY);
+ if (CHECK(efd < 0, "open", "errno %d\n", errno))
+ goto close_prog;
+ close(root_fd);
+
+ err = bpf_map_lookup_elem(resultmap_fd, &key, &descendant_of_result);
+ if (CHECK(err, "bpf_map_lookup_elem", "err %d errno %d\n", err, errno))
+ goto close_pmu;
+ if (CHECK(descendant_of_result != 1,
+ "descendant_of is true with same pid", "%d == %d\n",
+ descendant_of_result, 1))
+ goto close_pmu;
+
+ // Test that PID 1 an ancestor
+ bpf_map_update_elem(pidmap_fd, &key, &pid, 0);
+ ancestor_pid = 1;
+ bpf_map_update_elem(pidmap_fd, &ancestor_key, &ancestor_pid, 0);
+ bpf_map_update_elem(resultmap_fd, &key, &nonexistant, 0);
+
+ root_fd = open("/", O_RDONLY);
+ if (CHECK(efd < 0, "open", "errno %d\n", errno))
+ goto close_prog;
+ close(root_fd);
+
+ err = bpf_map_lookup_elem(resultmap_fd, &key, &descendant_of_result);
+ if (CHECK(err, "bpf_map_lookup_elem", "err %d errno %d\n", err, errno))
+ goto close_pmu;
+ if (CHECK(descendant_of_result != 1, "descendant_of reaches init",
+ "%d == %d\n", descendant_of_result, 1))
+ goto close_pmu;
+
+ // Test that PID 0 is an ancestor
+ bpf_map_update_elem(pidmap_fd, &key, &pid, 0);
+ ancestor_pid = 0;
+ bpf_map_update_elem(pidmap_fd, &ancestor_key, &ancestor_pid, 0);
+ bpf_map_update_elem(resultmap_fd, &key, &nonexistant, 0);
+
+ root_fd = open("/", O_RDONLY);
+ if (CHECK(efd < 0, "open", "errno %d\n", errno))
+ goto close_prog;
+ close(root_fd);
+
+ err = bpf_map_lookup_elem(resultmap_fd, &key, &descendant_of_result);
+ if (CHECK(err, "bpf_map_lookup_elem", "err %d errno %d\n", err, errno))
+ goto close_pmu;
+ if (CHECK(descendant_of_result != 1, "PID 0 is our ancestor",
+ "%d == %d\n", descendant_of_result, 1))
+ goto close_pmu;
+
+ // Test that we don't go over PID 0
+ bpf_map_update_elem(pidmap_fd, &key, &pid, 0);
+ ancestor_pid = -1;
+ bpf_map_update_elem(pidmap_fd, &ancestor_key, &ancestor_pid, 0);
+ bpf_map_update_elem(resultmap_fd, &key, &nonexistant, 0);
+
+ root_fd = open("/", O_RDONLY);
+ if (CHECK(efd < 0, "open", "errno %d\n", errno))
+ goto close_prog;
+ close(root_fd);
+
+ err = bpf_map_lookup_elem(resultmap_fd, &key, &descendant_of_result);
+ if (CHECK(err, "bpf_map_lookup_elem", "err %d errno %d\n", err, errno))
+ goto close_pmu;
+ if (CHECK(descendant_of_result != 0,
+ "descendant_of does not go over PID 0", "%d == %d\n",
+ descendant_of_result, 0))
+ goto close_pmu;
+
+ // Test that we are an ancestor of our child
+ pipe(pipefd);
+ child_pid = fork();
+ if (child_pid == -1) {
+ printf("fork failed\n");
+ goto close_pmu;
+ } else if (child_pid == 0) {
+ close(pipefd[1]);
+ read(pipefd[0], &marker, 1);
+
+ root_fd = open("/", O_RDONLY);
+ if (CHECK(efd < 0, "open", "errno %d\n", errno))
+ goto close_prog;
+ close(root_fd);
+
+ close(pipefd[0]);
+ _exit(EXIT_SUCCESS);
+ } else {
+ close(pipefd[0]);
+ bpf_map_update_elem(resultmap_fd, &key, &nonexistant, 0);
+ bpf_map_update_elem(pidmap_fd, &key, &child_pid, 0);
+ bpf_map_update_elem(pidmap_fd, &ancestor_key, &pid, 0);
+
+ write(pipefd[1], &marker, 1);
+ wait(NULL);
+ close(pipefd[1]);
+
+ err = bpf_map_lookup_elem(resultmap_fd, &key,
+ &descendant_of_result);
+ if (CHECK(err, "bpf_map_lookup_elem", "err %d errno %d\n", err,
+ errno))
+ goto close_pmu;
+ if (CHECK(descendant_of_result != 1, "descendant_of of parent",
+ "%d == %d\n", descendant_of_result, 1))
+ goto close_pmu;
+ }
+
+ // Test that a child of ours doesn't belong to our ancestors
+ bpf_map_update_elem(pidmap_fd, &key, &pid, 0);
+ bpf_map_update_elem(resultmap_fd, &key, &nonexistant, 0);
+
+ pipe(pipefd);
+ child_pid = fork();
+ if (child_pid == -1) {
+ printf("fork failed\n");
+ goto close_pmu;
+ } else if (child_pid == 0) {
+ close(pipefd[1]);
+ read(pipefd[0], marker, 1);
+ close(pipefd[0]);
+ _exit(EXIT_SUCCESS);
+ } else {
+ close(pipefd[0]);
+
+ bpf_map_update_elem(pidmap_fd, &ancestor_key, &child_pid, 0);
+
+ root_fd = open("/", O_RDONLY);
+ if (CHECK(efd < 0, "open", "errno %d\n", errno))
+ goto close_prog;
+ close(root_fd);
+
+ write(pipefd[1], marker, 1);
+ wait(NULL);
+ close(pipefd[1]);
+
+ err = bpf_map_lookup_elem(resultmap_fd, &key,
+ &descendant_of_result);
+ if (CHECK(err, "bpf_map_lookup_elem", "err %d errno %d\n", err,
+ errno))
+ goto close_pmu;
+ if (CHECK(descendant_of_result != 0, "descendant_of of child",
+ "%d == %d\n", descendant_of_result, 0))
+ goto close_pmu;
+ }
+
+ exit_code = EXIT_SUCCESS;
+ printf("%s:PASS\n", argv[0]);
+
+close_pmu:
+ close(pmu_fd);
+close_prog:
+ bpf_object__close(obj);
+fail:
+ return exit_code;
+}
--
2.17.1
^ permalink raw reply related
* [PATCH v6 bpf-next 2/3] bpf: sync kernel uapi headers
From: Javier Honduvilla Coto @ 2019-07-10 18:00 UTC (permalink / raw)
To: netdev; +Cc: yhs, kernel-team, jonhaslam
In-Reply-To: <20190710180025.94726-1-javierhonduco@fb.com>
Sync kernel uapi headers.
Signed-off-by: Javier Honduvilla Coto <javierhonduco@fb.com>
---
tools/include/uapi/linux/bpf.h | 20 +++++++++++++++++++-
1 file changed, 19 insertions(+), 1 deletion(-)
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index 402208581b2d..505ee91898c2 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -2710,6 +2710,23 @@ union bpf_attr {
* **-EPERM** if no permission to send the *sig*.
*
* **-EAGAIN** if bpf program can try again.
+ *
+ * int bpf_descendant_of(pid_t pid)
+ * Description
+ * Determine if the process identified by *pid* is an ancestor
+ * (or equal) of the user process executed in this tracing
+ * context. This is useful when filtering events happening
+ * to a process and all of its descendants.
+ *
+ * Note that *pid* must be the pid from the global namespace
+ * as the pids of the process chain will be resolved using the
+ * initial pid namespace viewer context.
+ * Return
+ * * 1 if the process identified by *pid* is an ancestor, or equal,
+ * of the currently executing process within the global pid
+ * namespace
+ *
+ * * 0 otherwise.
*/
#define __BPF_FUNC_MAPPER(FN) \
FN(unspec), \
@@ -2821,7 +2838,8 @@ union bpf_attr {
FN(strtoul), \
FN(sk_storage_get), \
FN(sk_storage_delete), \
- FN(send_signal),
+ FN(send_signal), \
+ FN(descendant_of),
/* integer value in 'imm' field of BPF_CALL instruction selects which helper
* function eBPF program intends to call
--
2.17.1
^ permalink raw reply related
* [PATCH v6 bpf-next 1/3] bpf: add bpf_descendant_of helper
From: Javier Honduvilla Coto @ 2019-07-10 18:00 UTC (permalink / raw)
To: netdev; +Cc: yhs, kernel-team, jonhaslam
In-Reply-To: <20190710180025.94726-1-javierhonduco@fb.com>
This patch adds the bpf_descendant_of helper which accepts a PID and
returns 1 if the PID of the process currently being executed is a
descendant of it or if it's itself. Returns 0 otherwise. The passed
PID should be the one as seen from the "global" pid namespace as the
processes' PIDs in the hierarchy are resolved using the context of said
initial namespace.
This is very useful in tracing programs when we want to filter by a
given PID and all the children it might spawn. The current workarounds
most people implement for this purpose have issues:
- Attaching to process spawning syscalls and dynamically add those PIDs
to some bpf map that would be used to filter is cumbersome and
potentially racy.
- Unrolling some loop to perform what this helper is doing consumes lots
of instructions. That and the impossibility to jump backwards makes it
really hard to be correct in really large process chains.
Signed-off-by: Javier Honduvilla Coto <javierhonduco@fb.com>
---
include/linux/bpf.h | 1 +
include/uapi/linux/bpf.h | 20 +++++++++++++++++++-
kernel/bpf/core.c | 1 +
kernel/bpf/helpers.c | 27 +++++++++++++++++++++++++++
kernel/trace/bpf_trace.c | 2 ++
5 files changed, 50 insertions(+), 1 deletion(-)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 18f4cc2c6acd..4e861138887d 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -1053,6 +1053,7 @@ extern const struct bpf_func_proto bpf_get_local_storage_proto;
extern const struct bpf_func_proto bpf_strtol_proto;
extern const struct bpf_func_proto bpf_strtoul_proto;
extern const struct bpf_func_proto bpf_tcp_sock_proto;
+extern const struct bpf_func_proto bpf_descendant_of_proto;
/* Shared helpers among cBPF and eBPF. */
void bpf_user_rnd_init_once(void);
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 5695ab53e354..7e8c2bd654f5 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -2713,6 +2713,23 @@ union bpf_attr {
* **-EPERM** if no permission to send the *sig*.
*
* **-EAGAIN** if bpf program can try again.
+ *
+ * int bpf_descendant_of(pid_t pid)
+ * Description
+ * Determine if the process identified by *pid* is an ancestor
+ * (or equal) of the user process executed in this tracing
+ * context. This is useful when filtering events happening
+ * to a process and all of its descendants.
+ *
+ * Note that *pid* must be the pid from the global namespace
+ * as the pids of the process chain will be resolved using the
+ * initial pid namespace viewer context.
+ * Return
+ * * 1 if the process identified by *pid* is an ancestor, or equal,
+ * of the currently executing process within the global pid
+ * namespace
+ *
+ * * 0 otherwise.
*/
#define __BPF_FUNC_MAPPER(FN) \
FN(unspec), \
@@ -2824,7 +2841,8 @@ union bpf_attr {
FN(strtoul), \
FN(sk_storage_get), \
FN(sk_storage_delete), \
- FN(send_signal),
+ FN(send_signal), \
+ FN(descendant_of),
/* integer value in 'imm' field of BPF_CALL instruction selects which helper
* function eBPF program intends to call
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index 16079550db6d..8f7f0ec8cded 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -2039,6 +2039,7 @@ const struct bpf_func_proto bpf_get_current_uid_gid_proto __weak;
const struct bpf_func_proto bpf_get_current_comm_proto __weak;
const struct bpf_func_proto bpf_get_current_cgroup_id_proto __weak;
const struct bpf_func_proto bpf_get_local_storage_proto __weak;
+const struct bpf_func_proto bpf_descendant_of_proto __weak;
const struct bpf_func_proto * __weak bpf_get_trace_printk_proto(void)
{
diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
index 5e28718928ca..2214194e5f49 100644
--- a/kernel/bpf/helpers.c
+++ b/kernel/bpf/helpers.c
@@ -11,6 +11,7 @@
#include <linux/uidgid.h>
#include <linux/filter.h>
#include <linux/ctype.h>
+#include <linux/init_task.h>
#include "../../lib/kstrtox.h"
@@ -487,3 +488,29 @@ const struct bpf_func_proto bpf_strtoul_proto = {
.arg4_type = ARG_PTR_TO_LONG,
};
#endif
+
+BPF_CALL_1(bpf_descendant_of, pid_t, pid)
+{
+ int result = 0;
+ struct task_struct *task = current;
+
+ if (pid == 0)
+ return 1;
+
+ while (task != &init_task) {
+ if (task->pid == pid) {
+ result = 1;
+ break;
+ }
+ task = rcu_dereference(task->real_parent);
+ }
+
+ return result;
+}
+
+const struct bpf_func_proto bpf_descendant_of_proto = {
+ .func = bpf_descendant_of,
+ .gpl_only = false,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_ANYTHING,
+};
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index ca1255d14576..797d7b4a8e9a 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -703,6 +703,8 @@ tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
return &bpf_get_prandom_u32_proto;
case BPF_FUNC_probe_read_str:
return &bpf_probe_read_str_proto;
+ case BPF_FUNC_descendant_of:
+ return &bpf_descendant_of_proto;
#ifdef CONFIG_CGROUPS
case BPF_FUNC_get_current_cgroup_id:
return &bpf_get_current_cgroup_id_proto;
--
2.17.1
^ permalink raw reply related
* Re: linux-next: build failure after merge of the net-next tree
From: Jason Gunthorpe @ 2019-07-10 17:52 UTC (permalink / raw)
To: Leon Romanovsky, Bernard Metzler
Cc: Stephen Rothwell, Doug Ledford, David Miller, Networking,
Linux Next Mailing List, Linux Kernel Mailing List
In-Reply-To: <20190709064346.GF7034@mtr-leonro.mtl.com>
On Tue, Jul 09, 2019 at 09:43:46AM +0300, Leon Romanovsky wrote:
> On Tue, Jul 09, 2019 at 01:56:36PM +1000, Stephen Rothwell wrote:
> > Hi all,
> >
> > After merging the net-next tree, today's linux-next build (x86_64
> > allmodconfig) failed like this:
> >
> > drivers/infiniband/sw/siw/siw_cm.c: In function 'siw_create_listen':
> > drivers/infiniband/sw/siw/siw_cm.c:1978:3: error: implicit declaration of function 'for_ifa'; did you mean 'fork_idle'? [-Werror=implicit-function-declaration]
> > for_ifa(in_dev)
> > ^~~~~~~
> > fork_idle
> > drivers/infiniband/sw/siw/siw_cm.c:1978:18: error: expected ';' before '{' token
> > for_ifa(in_dev)
> > ^
> > ;
> > {
> > ~
> >
> > Caused by commit
> >
> > 6c52fdc244b5 ("rdma/siw: connection management")
> >
> > from the rdma tree. I don't know why this didn't fail after I mereged
> > that tree.
>
> I had the same question, because I have this fix for a couple of days already.
>
> From 56c9e15ec670af580daa8c3ffde9503af3042d67 Mon Sep 17 00:00:00 2001
> From: Leon Romanovsky <leonro@mellanox.com>
> Date: Sun, 7 Jul 2019 10:43:42 +0300
> Subject: [PATCH] Fixup to build SIW issue
>
> Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
> drivers/infiniband/sw/siw/siw_cm.c | 5 ++---
> 1 file changed, 2 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/infiniband/sw/siw/siw_cm.c b/drivers/infiniband/sw/siw/siw_cm.c
> index 8e618cb7261f..c883bf514341 100644
> +++ b/drivers/infiniband/sw/siw/siw_cm.c
> @@ -1954,6 +1954,7 @@ static void siw_drop_listeners(struct iw_cm_id *id)
> int siw_create_listen(struct iw_cm_id *id, int backlog)
> {
> struct net_device *dev = to_siw_dev(id->device)->netdev;
> + const struct in_ifaddr *ifa;
> int rv = 0, listeners = 0;
>
> siw_dbg(id->device, "id 0x%p: backlog %d\n", id, backlog);
> @@ -1975,8 +1976,7 @@ int siw_create_listen(struct iw_cm_id *id, int backlog)
> id, &s_laddr.sin_addr, ntohs(s_laddr.sin_port),
> &s_raddr->sin_addr, ntohs(s_raddr->sin_port));
>
> - for_ifa(in_dev)
> - {
> + in_dev_for_each_ifa_rcu(ifa, in_dev) {
> if (ipv4_is_zeronet(s_laddr.sin_addr.s_addr) ||
Hum. There is no rcu lock held here and we can't use RCU anyhow as
siw_listen_address will sleep.
I think this needs to use rtnl, as below. Bernard, please urgently
confirm. Thanks
diff --git a/drivers/infiniband/sw/siw/siw_cm.c b/drivers/infiniband/sw/siw/siw_cm.c
index 8e618cb7261f62..ee98e96a5bfaba 100644
--- a/drivers/infiniband/sw/siw/siw_cm.c
+++ b/drivers/infiniband/sw/siw/siw_cm.c
@@ -1965,6 +1965,7 @@ int siw_create_listen(struct iw_cm_id *id, int backlog)
*/
if (id->local_addr.ss_family == AF_INET) {
struct in_device *in_dev = in_dev_get(dev);
+ const struct in_ifaddr *ifa;
struct sockaddr_in s_laddr, *s_raddr;
memcpy(&s_laddr, &id->local_addr, sizeof(s_laddr));
@@ -1975,8 +1976,8 @@ int siw_create_listen(struct iw_cm_id *id, int backlog)
id, &s_laddr.sin_addr, ntohs(s_laddr.sin_port),
&s_raddr->sin_addr, ntohs(s_raddr->sin_port));
- for_ifa(in_dev)
- {
+ rtnl_lock();
+ in_dev_for_each_ifa_rtnl(ifa, in_dev) {
if (ipv4_is_zeronet(s_laddr.sin_addr.s_addr) ||
s_laddr.sin_addr.s_addr == ifa->ifa_address) {
s_laddr.sin_addr.s_addr = ifa->ifa_address;
@@ -1988,7 +1989,7 @@ int siw_create_listen(struct iw_cm_id *id, int backlog)
listeners++;
}
}
- endfor_ifa(in_dev);
+ rtnl_unlock();
in_dev_put(in_dev);
} else if (id->local_addr.ss_family == AF_INET6) {
struct inet6_dev *in6_dev = in6_dev_get(dev);
^ permalink raw reply related
* Re: [RFC bpf-next 2/8] bpf: extend list based insn patching infra to verification layer
From: Andrii Nakryiko @ 2019-07-10 17:50 UTC (permalink / raw)
To: Jiong Wang
Cc: Alexei Starovoitov, Daniel Borkmann, Edward Cree, Naveen N. Rao,
Andrii Nakryiko, Jakub Kicinski, bpf, Networking, oss-drivers
In-Reply-To: <1562275611-31790-3-git-send-email-jiong.wang@netronome.com>
On Thu, Jul 4, 2019 at 2:32 PM Jiong Wang <jiong.wang@netronome.com> wrote:
>
> Verification layer also needs to handle auxiliar info as well as adjusting
> subprog start.
>
> At this layer, insns inside patch buffer could be jump, but they should
> have been resolved, meaning they shouldn't jump to insn outside of the
> patch buffer. Lineration function for this layer won't touch insns inside
> patch buffer.
>
> Adjusting subprog is finished along with adjusting jump target when the
> input will cover bpf to bpf call insn, re-register subprog start is cheap.
> But adjustment when there is insn deleteion is not considered yet.
>
> Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
> ---
> kernel/bpf/verifier.c | 150 ++++++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 150 insertions(+)
>
> diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
> index a2e7637..2026d64 100644
> --- a/kernel/bpf/verifier.c
> +++ b/kernel/bpf/verifier.c
> @@ -8350,6 +8350,156 @@ static void opt_hard_wire_dead_code_branches(struct bpf_verifier_env *env)
> }
> }
>
> +/* Linearize bpf list insn to array (verifier layer). */
> +static struct bpf_verifier_env *
> +verifier_linearize_list_insn(struct bpf_verifier_env *env,
> + struct bpf_list_insn *list)
It's unclear why this returns env back? It's not allocating a new env,
so it's weird and unnecessary. Just return error code.
> +{
> + u32 *idx_map, idx, orig_cnt, fini_cnt = 0;
> + struct bpf_subprog_info *new_subinfo;
> + struct bpf_insn_aux_data *new_data;
> + struct bpf_prog *prog = env->prog;
> + struct bpf_verifier_env *ret_env;
> + struct bpf_insn *insns, *insn;
> + struct bpf_list_insn *elem;
> + int ret;
> +
> + /* Calculate final size. */
> + for (elem = list; elem; elem = elem->next)
> + if (!(elem->flag & LIST_INSN_FLAG_REMOVED))
> + fini_cnt++;
> +
> + orig_cnt = prog->len;
> + insns = prog->insnsi;
> + /* If prog length remains same, nothing else to do. */
> + if (fini_cnt == orig_cnt) {
> + for (insn = insns, elem = list; elem; elem = elem->next, insn++)
> + *insn = elem->insn;
> + return env;
> + }
> + /* Realloc insn buffer when necessary. */
> + if (fini_cnt > orig_cnt)
> + prog = bpf_prog_realloc(prog, bpf_prog_size(fini_cnt),
> + GFP_USER);
> + if (!prog)
> + return ERR_PTR(-ENOMEM);
> + insns = prog->insnsi;
> + prog->len = fini_cnt;
> + ret_env = env;
> +
> + /* idx_map[OLD_IDX] = NEW_IDX */
> + idx_map = kvmalloc(orig_cnt * sizeof(u32), GFP_KERNEL);
> + if (!idx_map)
> + return ERR_PTR(-ENOMEM);
> + memset(idx_map, 0xff, orig_cnt * sizeof(u32));
> +
> + /* Use the same alloc method used when allocating env->insn_aux_data. */
> + new_data = vzalloc(array_size(sizeof(*new_data), fini_cnt));
> + if (!new_data) {
> + kvfree(idx_map);
> + return ERR_PTR(-ENOMEM);
> + }
> +
> + /* Copy over insn + calculate idx_map. */
> + for (idx = 0, elem = list; elem; elem = elem->next) {
> + int orig_idx = elem->orig_idx - 1;
> +
> + if (orig_idx >= 0) {
> + idx_map[orig_idx] = idx;
> +
> + if (elem->flag & LIST_INSN_FLAG_REMOVED)
> + continue;
> +
> + new_data[idx] = env->insn_aux_data[orig_idx];
> +
> + if (elem->flag & LIST_INSN_FLAG_PATCHED)
> + new_data[idx].zext_dst =
> + insn_has_def32(env, &elem->insn);
> + } else {
> + new_data[idx].seen = true;
> + new_data[idx].zext_dst = insn_has_def32(env,
> + &elem->insn);
> + }
> + insns[idx++] = elem->insn;
> + }
> +
> + new_subinfo = kvzalloc(sizeof(env->subprog_info), GFP_KERNEL);
> + if (!new_subinfo) {
> + kvfree(idx_map);
> + vfree(new_data);
> + return ERR_PTR(-ENOMEM);
> + }
> + memcpy(new_subinfo, env->subprog_info, sizeof(env->subprog_info));
> + memset(env->subprog_info, 0, sizeof(env->subprog_info));
> + env->subprog_cnt = 0;
> + env->prog = prog;
> + ret = add_subprog(env, 0);
> + if (ret < 0) {
> + ret_env = ERR_PTR(ret);
> + goto free_all_ret;
> + }
> + /* Relocate jumps using idx_map.
> + * old_dst = jmp_insn.old_target + old_pc + 1;
> + * new_dst = idx_map[old_dst] = jmp_insn.new_target + new_pc + 1;
> + * jmp_insn.new_target = new_dst - new_pc - 1;
> + */
> + for (idx = 0, elem = list; elem; elem = elem->next) {
> + int orig_idx = elem->orig_idx;
> +
> + if (elem->flag & LIST_INSN_FLAG_REMOVED)
> + continue;
> + if ((elem->flag & LIST_INSN_FLAG_PATCHED) || !orig_idx) {
> + idx++;
> + continue;
> + }
> +
> + ret = bpf_jit_adj_imm_off(&insns[idx], orig_idx - 1, idx,
> + idx_map);
> + if (ret < 0) {
> + ret_env = ERR_PTR(ret);
> + goto free_all_ret;
> + }
> + /* Recalculate subprog start as we are at bpf2bpf call insn. */
> + if (ret > 0) {
> + ret = add_subprog(env, idx + insns[idx].imm + 1);
> + if (ret < 0) {
> + ret_env = ERR_PTR(ret);
> + goto free_all_ret;
> + }
> + }
> + idx++;
> + }
> + if (ret < 0) {
> + ret_env = ERR_PTR(ret);
> + goto free_all_ret;
> + }
> +
> + env->subprog_info[env->subprog_cnt].start = fini_cnt;
> + for (idx = 0; idx <= env->subprog_cnt; idx++)
> + new_subinfo[idx].start = env->subprog_info[idx].start;
> + memcpy(env->subprog_info, new_subinfo, sizeof(env->subprog_info));
> +
> + /* Adjust linfo.
> + * FIXME: no support for insn removal at the moment.
> + */
> + if (prog->aux->nr_linfo) {
> + struct bpf_line_info *linfo = prog->aux->linfo;
> + u32 nr_linfo = prog->aux->nr_linfo;
> +
> + for (idx = 0; idx < nr_linfo; idx++)
> + linfo[idx].insn_off = idx_map[linfo[idx].insn_off];
> + }
> + vfree(env->insn_aux_data);
> + env->insn_aux_data = new_data;
> + goto free_mem_list_ret;
> +free_all_ret:
> + vfree(new_data);
> +free_mem_list_ret:
> + kvfree(new_subinfo);
> + kvfree(idx_map);
> + return ret_env;
> +}
> +
> static int opt_remove_dead_code(struct bpf_verifier_env *env)
> {
> struct bpf_insn_aux_data *aux_data = env->insn_aux_data;
> --
> 2.7.4
>
^ permalink raw reply
* Re: [RFC bpf-next 1/8] bpf: introducing list based insn patching infra to core layer
From: Andrii Nakryiko @ 2019-07-10 17:49 UTC (permalink / raw)
To: Jiong Wang
Cc: Alexei Starovoitov, Daniel Borkmann, Edward Cree, Naveen N. Rao,
Andrii Nakryiko, Jakub Kicinski, bpf, Networking, oss-drivers
In-Reply-To: <1562275611-31790-2-git-send-email-jiong.wang@netronome.com>
On Thu, Jul 4, 2019 at 2:32 PM Jiong Wang <jiong.wang@netronome.com> wrote:
>
> This patch introduces list based bpf insn patching infra to bpf core layer
> which is lower than verification layer.
>
> This layer has bpf insn sequence as the solo input, therefore the tasks
> to be finished during list linerization is:
> - copy insn
> - relocate jumps
> - relocation line info.
>
> Suggested-by: Alexei Starovoitov <ast@kernel.org>
> Suggested-by: Edward Cree <ecree@solarflare.com>
> Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
> ---
> include/linux/filter.h | 25 +++++
> kernel/bpf/core.c | 268 +++++++++++++++++++++++++++++++++++++++++++++++++
> 2 files changed, 293 insertions(+)
>
> diff --git a/include/linux/filter.h b/include/linux/filter.h
> index 1fe53e7..1fea68c 100644
> --- a/include/linux/filter.h
> +++ b/include/linux/filter.h
> @@ -842,6 +842,31 @@ struct bpf_prog *bpf_patch_insn_single(struct bpf_prog *prog, u32 off,
> const struct bpf_insn *patch, u32 len);
> int bpf_remove_insns(struct bpf_prog *prog, u32 off, u32 cnt);
>
> +int bpf_jit_adj_imm_off(struct bpf_insn *insn, int old_idx, int new_idx,
> + int idx_map[]);
> +
> +#define LIST_INSN_FLAG_PATCHED 0x1
> +#define LIST_INSN_FLAG_REMOVED 0x2
> +struct bpf_list_insn {
> + struct bpf_insn insn;
> + struct bpf_list_insn *next;
> + s32 orig_idx;
> + u32 flag;
> +};
> +
> +struct bpf_list_insn *bpf_create_list_insn(struct bpf_prog *prog);
> +void bpf_destroy_list_insn(struct bpf_list_insn *list);
> +/* Replace LIST_INSN with new list insns generated from PATCH. */
> +struct bpf_list_insn *bpf_patch_list_insn(struct bpf_list_insn *list_insn,
> + const struct bpf_insn *patch,
> + u32 len);
> +/* Pre-patch list_insn with insns inside PATCH, meaning LIST_INSN is not
> + * touched. New list insns are inserted before it.
> + */
> +struct bpf_list_insn *bpf_prepatch_list_insn(struct bpf_list_insn *list_insn,
> + const struct bpf_insn *patch,
> + u32 len);
> +
> void bpf_clear_redirect_map(struct bpf_map *map);
>
> static inline bool xdp_return_frame_no_direct(void)
> diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
> index e2c1b43..e60703e 100644
> --- a/kernel/bpf/core.c
> +++ b/kernel/bpf/core.c
> @@ -502,6 +502,274 @@ int bpf_remove_insns(struct bpf_prog *prog, u32 off, u32 cnt)
> return WARN_ON_ONCE(bpf_adj_branches(prog, off, off + cnt, off, false));
> }
>
> +int bpf_jit_adj_imm_off(struct bpf_insn *insn, int old_idx, int new_idx,
> + s32 idx_map[])
> +{
> + u8 code = insn->code;
> + s64 imm;
> + s32 off;
> +
> + if (BPF_CLASS(code) != BPF_JMP && BPF_CLASS(code) != BPF_JMP32)
> + return 0;
> +
> + if (BPF_CLASS(code) == BPF_JMP &&
> + (BPF_OP(code) == BPF_EXIT ||
> + (BPF_OP(code) == BPF_CALL && insn->src_reg != BPF_PSEUDO_CALL)))
> + return 0;
> +
> + /* BPF to BPF call. */
> + if (BPF_OP(code) == BPF_CALL) {
> + imm = idx_map[old_idx + insn->imm + 1] - new_idx - 1;
> + if (imm < S32_MIN || imm > S32_MAX)
> + return -ERANGE;
> + insn->imm = imm;
> + return 1;
> + }
> +
> + /* Jump. */
> + off = idx_map[old_idx + insn->off + 1] - new_idx - 1;
> + if (off < S16_MIN || off > S16_MAX)
> + return -ERANGE;
> + insn->off = off;
> + return 0;
> +}
> +
> +void bpf_destroy_list_insn(struct bpf_list_insn *list)
> +{
> + struct bpf_list_insn *elem, *next;
> +
> + for (elem = list; elem; elem = next) {
> + next = elem->next;
> + kvfree(elem);
> + }
> +}
> +
> +struct bpf_list_insn *bpf_create_list_insn(struct bpf_prog *prog)
> +{
> + unsigned int idx, len = prog->len;
> + struct bpf_list_insn *hdr, *prev;
> + struct bpf_insn *insns;
> +
> + hdr = kvzalloc(sizeof(*hdr), GFP_KERNEL);
> + if (!hdr)
> + return ERR_PTR(-ENOMEM);
> +
> + insns = prog->insnsi;
> + hdr->insn = insns[0];
> + hdr->orig_idx = 1;
> + prev = hdr;
I'm not sure why you need this "prologue" instead of handling first
instruction uniformly in for loop below?
> +
> + for (idx = 1; idx < len; idx++) {
> + struct bpf_list_insn *node = kvzalloc(sizeof(*node),
> + GFP_KERNEL);
> +
> + if (!node) {
> + /* Destroy what has been allocated. */
> + bpf_destroy_list_insn(hdr);
> + return ERR_PTR(-ENOMEM);
> + }
> + node->insn = insns[idx];
> + node->orig_idx = idx + 1;
Why orig_idx is 1-based? It's really confusing.
> + prev->next = node;
> + prev = node;
> + }
> +
> + return hdr;
> +}
> +
> +/* Linearize bpf list insn to array. */
> +static struct bpf_prog *bpf_linearize_list_insn(struct bpf_prog *prog,
> + struct bpf_list_insn *list)
> +{
> + u32 *idx_map, idx, prev_idx, fini_cnt = 0, orig_cnt = prog->len;
> + struct bpf_insn *insns, *insn;
> + struct bpf_list_insn *elem;
> +
> + /* Calculate final size. */
> + for (elem = list; elem; elem = elem->next)
> + if (!(elem->flag & LIST_INSN_FLAG_REMOVED))
> + fini_cnt++;
> +
> + insns = prog->insnsi;
> + /* If prog length remains same, nothing else to do. */
> + if (fini_cnt == orig_cnt) {
> + for (insn = insns, elem = list; elem; elem = elem->next, insn++)
> + *insn = elem->insn;
> + return prog;
> + }
> + /* Realloc insn buffer when necessary. */
> + if (fini_cnt > orig_cnt)
> + prog = bpf_prog_realloc(prog, bpf_prog_size(fini_cnt),
> + GFP_USER);
> + if (!prog)
> + return ERR_PTR(-ENOMEM);
> + insns = prog->insnsi;
> + prog->len = fini_cnt;
> +
> + /* idx_map[OLD_IDX] = NEW_IDX */
> + idx_map = kvmalloc(orig_cnt * sizeof(u32), GFP_KERNEL);
> + if (!idx_map)
> + return ERR_PTR(-ENOMEM);
> + memset(idx_map, 0xff, orig_cnt * sizeof(u32));
> +
> + /* Copy over insn + calculate idx_map. */
> + for (idx = 0, elem = list; elem; elem = elem->next) {
> + int orig_idx = elem->orig_idx - 1;
> +
> + if (orig_idx >= 0) {
> + idx_map[orig_idx] = idx;
> +
> + if (elem->flag & LIST_INSN_FLAG_REMOVED)
> + continue;
> + }
> + insns[idx++] = elem->insn;
> + }
> +
> + /* Relocate jumps using idx_map.
> + * old_dst = jmp_insn.old_target + old_pc + 1;
> + * new_dst = idx_map[old_dst] = jmp_insn.new_target + new_pc + 1;
> + * jmp_insn.new_target = new_dst - new_pc - 1;
> + */
> + for (idx = 0, prev_idx = 0, elem = list; elem; elem = elem->next) {
> + int ret, orig_idx;
> +
> + /* A removed insn doesn't increase new_pc */
> + if (elem->flag & LIST_INSN_FLAG_REMOVED)
> + continue;
> +
> + orig_idx = elem->orig_idx - 1;
> + ret = bpf_jit_adj_imm_off(&insns[idx],
> + orig_idx >= 0 ? orig_idx : prev_idx,
> + idx, idx_map);
> + idx++;
> + if (ret < 0) {
> + kvfree(idx_map);
> + return ERR_PTR(ret);
> + }
> + if (orig_idx >= 0)
> + /* Record prev_idx. it is used for relocating jump insn
> + * inside patch buffer. For example, when doing jit
> + * blinding, a jump could be moved to some other
> + * positions inside the patch buffer, and its old_dst
> + * could be calculated using prev_idx.
> + */
> + prev_idx = orig_idx;
> + }
> +
> + /* Adjust linfo.
> + *
> + * NOTE: the prog reached core layer has been adjusted to contain insns
> + * for single function, however linfo contains information for
> + * whole program, so we need to make sure linfo beyond current
> + * function is handled properly.
> + */
> + if (prog->aux->nr_linfo) {
> + u32 linfo_idx, insn_start, insn_end, nr_linfo, idx, delta;
> + struct bpf_line_info *linfo;
> +
> + linfo_idx = prog->aux->linfo_idx;
> + linfo = &prog->aux->linfo[linfo_idx];
> + insn_start = linfo[0].insn_off;
> + insn_end = insn_start + orig_cnt;
> + nr_linfo = prog->aux->nr_linfo - linfo_idx;
> + delta = fini_cnt - orig_cnt;
> + for (idx = 0; idx < nr_linfo; idx++) {
> + int adj_off;
> +
> + if (linfo[idx].insn_off >= insn_end) {
> + linfo[idx].insn_off += delta;
> + continue;
> + }
> +
> + adj_off = linfo[idx].insn_off - insn_start;
> + linfo[idx].insn_off = idx_map[adj_off] + insn_start;
> + }
> + }
> + kvfree(idx_map);
> +
> + return prog;
> +}
> +
> +struct bpf_list_insn *bpf_patch_list_insn(struct bpf_list_insn *list_insn,
> + const struct bpf_insn *patch,
> + u32 len)
> +{
> + struct bpf_list_insn *prev, *next;
> + u32 insn_delta = len - 1;
> + u32 idx;
> +
> + list_insn->insn = *patch;
> + list_insn->flag |= LIST_INSN_FLAG_PATCHED;
> +
> + /* Since our patchlet doesn't expand the image, we're done. */
> + if (insn_delta == 0)
> + return list_insn;
> +
> + len--;
> + patch++;
> +
> + prev = list_insn;
> + next = list_insn->next;
> + for (idx = 0; idx < len; idx++) {
> + struct bpf_list_insn *node = kvzalloc(sizeof(*node),
> + GFP_KERNEL);
> +
> + if (!node) {
> + /* Link what's allocated, so list destroyer could
> + * free them.
> + */
> + prev->next = next;
Why this special handling, if you can just insert element so that list
is well-formed after each instruction?
> + return ERR_PTR(-ENOMEM);
> + }
> +
> + node->insn = patch[idx];
> + prev->next = node;
> + prev = node;
E.g.,
node->next = next;
prev->next = node;
prev = node;
> + }
> +
> + prev->next = next;
And no need for this either.
> + return prev;
> +}
> +
> +struct bpf_list_insn *bpf_prepatch_list_insn(struct bpf_list_insn *list_insn,
> + const struct bpf_insn *patch,
> + u32 len)
prepatch and patch functions should share the same logic.
Prepend is just that - insert all instructions from buffer before current insns.
Patch -> replace current one with first instriction in a buffer, then
prepend remaining ones before the next instruction (so patch should
call info prepend, with adjusted count and array pointer).
> +{
> + struct bpf_list_insn *prev, *node, *begin_node;
> + u32 idx;
> +
> + if (!len)
> + return list_insn;
> +
> + node = kvzalloc(sizeof(*node), GFP_KERNEL);
> + if (!node)
> + return ERR_PTR(-ENOMEM);
> + node->insn = patch[0];
> + begin_node = node;
> + prev = node;
> +
> + for (idx = 1; idx < len; idx++) {
> + node = kvzalloc(sizeof(*node), GFP_KERNEL);
> + if (!node) {
> + node = begin_node;
> + /* Release what's has been allocated. */
> + while (node) {
> + struct bpf_list_insn *next = node->next;
> +
> + kvfree(node);
> + node = next;
> + }
> + return ERR_PTR(-ENOMEM);
> + }
> + node->insn = patch[idx];
> + prev->next = node;
> + prev = node;
> + }
> +
> + prev->next = list_insn;
> + return begin_node;
> +}
> +
> void bpf_prog_kallsyms_del_subprogs(struct bpf_prog *fp)
> {
> int i;
> --
> 2.7.4
>
^ permalink raw reply
* Re: [RFC bpf-next 0/8] bpf: accelerate insn patching speed
From: Andrii Nakryiko @ 2019-07-10 17:39 UTC (permalink / raw)
To: Jiong Wang
Cc: Alexei Starovoitov, Daniel Borkmann, Edward Cree, Naveen N. Rao,
Andrii Nakryiko, Jakub Kicinski, bpf, Networking, oss-drivers
In-Reply-To: <1562275611-31790-1-git-send-email-jiong.wang@netronome.com>
On Thu, Jul 4, 2019 at 2:31 PM Jiong Wang <jiong.wang@netronome.com> wrote:
>
> This is an RFC based on latest bpf-next about acclerating insn patching
> speed, it is now near the shape of final PATCH set, and we could see the
> changes migrating to list patching would brings, so send out for
> comments. Most of the info are in cover letter. I splitted the code in a
> way to show API migration more easily.
Hey Jiong,
Sorry, took me a while to get to this and learn more about instruction
patching. Overall this looks good and I think is a good direction.
I'll post high-level feedback here, and some more
implementation-specific ones in corresponding patches.
>
> Test Results
> ===
> - Full pass on test_verifier/test_prog/test_prog_32 under all three
> modes (interpreter, JIT, JIT with blinding).
>
> - Benchmarking shows 10 ~ 15x faster on medium sized prog, and reduce
> patching time from 5100s (nearly one and a half hour) to less than
> 0.5s for 1M insn patching.
>
> Known Issues
> ===
> - The following warning is triggered when running scale test which
> contains 1M insns and patching:
> warning of mm/page_alloc.c:4639 __alloc_pages_nodemask+0x29e/0x330
>
> This is caused by existing code, it can be reproduced on bpf-next
> master with jit blinding enabled, then run scale unit test, it will
> shown up after half an hour. After this set, patching is very fast, so
> it shows up quickly.
>
> - No line info adjustment support when doing insn delete, subprog adj
> is with bug when doing insn delete as well. Generally, removal of insns
> could possibly cause remove of entire line or subprog, therefore
> entries of prog->aux->linfo or env->subprog needs to be deleted. I
> don't have good idea and clean code for integrating this into the
> linearization code at the moment, will do more experimenting,
> appreciate ideas and suggestions on this.
Is there any specific problem to detect which line info to delete? Or
what am I missing besides careful implementation?
>
> Insn delete doesn't happen on normal programs, for example Cilium
> benchmarks, and happens rarely on test_progs, so the test coverage is
> not good. That's also why this RFC have a full pass on selftest with
> this known issue.
I hope you'll add test for deletion (and w/ corresponding line info)
in final patch set :)
>
> - Could further use mem pool to accelerate the speed, changes are trivial
> on top of this RFC, and could be 2x extra faster. Not included in this
> RFC as reducing the algo complexity from quadratic to linear of insn
> number is the first step.
Honestly, I think that would add more complexity than necessary, and I
think we can further speed up performance without that, see below.
>
> Background
> ===
> This RFC aims to accelerate BPF insn patching speed, patching means expand
> one bpf insn at any offset inside bpf prog into a set of new insns, or
> remove insns.
>
> At the moment, insn patching is quadratic of insn number, this is due to
> branch targets of jump insns needs to be adjusted, and the algo used is:
>
> for insn inside prog
> patch insn + regeneate bpf prog
> for insn inside new prog
> adjust jump target
>
> This is causing significant time spending when a bpf prog requires large
> amount of patching on different insns. Benchmarking shows it could take
> more than half minutes to finish patching when patching number is more
> than 50K, and the time spent could be more than one hour when patching
> number is around 1M.
>
> 15000 : 3s
> 45000 : 29s
> 95000 : 125s
> 195000 : 712s
> 1000000 : 5100s
>
> This RFC introduces new patching infrastructure. Before doing insn
> patching, insns in bpf prog are turned into a singly linked list, insert
> new insns just insert new list node, delete insns just set delete flag.
> And finally, the list is linearized back into array, and branch target
> adjustment is done for all jump insns during linearization. This algo
> brings the time complexity from quadratic to linear of insn number.
>
> Benchmarking shows the new patching infrastructure could be 10 ~ 15x faster
> on medium sized prog, and for a 1M patching it reduce the time from 5100s
> to less than 0.5s.
>
> Patching API
> ===
> Insn patching could happen on two layers inside BPF. One is "core layer"
> where only BPF insns are patched. The other is "verification layer" where
> insns have corresponding aux info as well high level subprog info, so
> insn patching means aux info needs to be patched as well, and subprog info
> needs to be adjusted. BPF prog also has debug info associated, so line info
> should always be updated after insn patching.
>
> So, list creation, destroy, insert, delete is the same for both layer,
> but lineration is different. "verification layer" patching require extra
> work. Therefore the patch APIs are:
>
> list creation: bpf_create_list_insn
> list patch: bpf_patch_list_insn
> list pre-patch: bpf_prepatch_list_insn
I think pre-patch name is very confusing, until I read full
description I couldn't understand what it's supposed to be used for.
Speaking of bpf_patch_list_insn, patch is also generic enough to leave
me wondering whether instruction buffer is inserted after instruction,
or instruction is replaced with a bunch of instructions.
So how about two more specific names:
bpf_patch_list_insn -> bpf_list_insn_replace (meaning replace given
instruction with a list of patch instructions)
bpf_prepatch_list_insn -> bpf_list_insn_prepend (well, I think this
one is pretty clear).
> list lineration (core layer): prog = bpf_linearize_list_insn(prog, list)
> list lineration (veri layer): env = verifier_linearize_list_insn(env, list)
These two functions are both quite involved, as well as share a lot of
common code. I'd rather have one linearize instruction, that takes env
as an optional parameter. If env is specified (which is the case for
all cases except for constant blinding pass), then adjust aux_data and
subprogs along the way.
This would keep logic less duplicated and shouldn't complexity beyond
few null checks in few places.
> list destroy: bpf_destroy_list_insn
>
I'd also add a macro foreach_list_insn instead of explicit for loops
in multiple places. That would also allow to skip deleted instructions
transparently.
> list patch could change the insn at patch point, it will invalid the aux
typo: invalid -> invalidate
> info at patching point. list pre-patch insert new insns before patch point
> where the insn and associated aux info are not touched, it is used for
> example in convert_ctx_access when generating prologue.
>
> Typical API sequence for one patching pass:
>
> struct bpf_list_insn list = bpf_create_list_insn(struct bpf_prog);
> for (elem = list; elem; elem = elem->next)
> patch_buf = gen_patch_buf_logic;
> elem = bpf_patch_list_insn(elem, patch_buf, cnt);
> bpf_prog = bpf_linearize_list_insn(list)
> bpf_destroy_list_insn(list)
>
> Several patching passes could also share the same list:
>
> struct bpf_list_insn list = bpf_create_list_insn(struct bpf_prog);
> for (elem = list; elem; elem = elem->next)
> patch_buf = gen_patch_buf_logic1;
> elem = bpf_patch_list_insn(elem, patch_buf, cnt);
> for (elem = list; elem; elem = elem->next)
> patch_buf = gen_patch_buf_logic2;
> elem = bpf_patch_list_insn(elem, patch_buf, cnt);
> bpf_prog = bpf_linearize_list_insn(list)
> bpf_destroy_list_insn(list)
>
> but note new inserted insns int early passes won't have aux info except
> zext info. So, if one patch pass requires all aux info updated and
> recalculated for all insns including those pathced, it should first
> linearize the old list, then re-create the list. The RFC always create and
> linearize the list for each migrated patching pass separately.
I think we should do just one list creation, few passes of patching
and then linearize once. That will save quite a lot of memory
allocation and will speed up a lot of things. All the verifier
patching happens one after the other without any other functionality
in between, so there shouldn't be any problem.
As for aux_data. We can solve that even more simply and reliably by
storing a pointer along the struct bpf_list_insn (btw, how about
calling it bpf_patchable_insn?).
Here's how I propose to represent this patchable instruction:
struct bpf_list_insn {
struct bpf_insn insn;
struct bpf_list_insn *next;
struct bpf_list_insn *target;
struct bpf_insn_aux_data *aux_data;
s32 orig_idx; // can repurpose this to have three meanings:
// -2 - deleted
// -1 - patched/inserted insn
// >=0 - original idx
};
The idea would be as follows:
1. when creating original list, target pointer will point directly to
a patchable instruction wrapper for jumps/calls. This will allow to
stop tracking and re-calculating jump offsets and instruction indicies
until linearization.
2. aux_data is also filled at that point. Later at linearization time
you'd just iterate over all the instructions in final order and copy
original aux_data, if it's present. And then just repace env's
aux_data array at the end, should be very simple and fast.
3. during fix_bpf_calls, zext, ctx rewrite passes, we'll reuse the
same list of instructions and those passes will just keep inserting
instruction buffers. Given we have restriction that all the jumps are
only within patch buffer, it will be trivial to construct proper
patchable instruction wrappers for newly added instructions, with NULL
for aux_data and possibly non-NULL target (if it's a JMP insn).
4. After those passes, linearize, adjust subprogs (for this you'll
probably still need to create index mapping, right?), copy or create
new aux_data.
5. Done.
What do you think? I think this should be overall simpler and faster.
But let me know if I'm missing something.
>
> Compared with old patching code, this new infrastructure has much less core
> code, even though the final code has a couple of extra lines but that is
> mostly due to for list based infrastructure, we need to do more error
> checks, so the list and associated aux data structure could be freed when
> errors happens.
>
> Patching Restrictions
> ===
> - For core layer, the linearization assume no new jumps inside patch buf.
> Currently, the only user of this layer is jit blinding.
> - For verifier layer, there could be new jumps inside patch buf, but
> they should have branch target resolved themselves, meaning new jumps
> doesn't jump to insns out of the patch buf. This is the case for all
> existing verifier layer users.
> - bpf_insn_aux_data for all patched insns including the one at patch
> point are invalidated, only 32-bit zext info will be recalcuated.
> If the aux data of insn at patch point needs to be retained, it is
> purely insn insertion, so need to use the pre-patch API.
>
> I plan to send out a PATCH set once I finished insn deletion line info adj
> support, please have a looks at this RFC, and appreciate feedbacks.
>
> Jiong Wang (8):
> bpf: introducing list based insn patching infra to core layer
> bpf: extend list based insn patching infra to verification layer
> bpf: migrate jit blinding to list patching infra
> bpf: migrate convert_ctx_accesses to list patching infra
> bpf: migrate fixup_bpf_calls to list patching infra
> bpf: migrate zero extension opt to list patching infra
> bpf: migrate insn remove to list patching infra
> bpf: delete all those code around old insn patching infrastructure
>
> include/linux/bpf_verifier.h | 1 -
> include/linux/filter.h | 27 +-
> kernel/bpf/core.c | 431 +++++++++++++++++-----------
> kernel/bpf/verifier.c | 649 +++++++++++++++++++------------------------
> 4 files changed, 580 insertions(+), 528 deletions(-)
>
> --
> 2.7.4
>
^ permalink raw reply
* Re: [RFC PATCH net-next 0/3] net: batched receive in GRO path
From: Eric Dumazet @ 2019-07-10 17:39 UTC (permalink / raw)
To: Edward Cree, Eric Dumazet, Paolo Abeni, David Miller; +Cc: netdev
In-Reply-To: <4516a34a-5a88-88ef-e761-7512dff4f3ce@solarflare.com>
On 7/10/19 6:47 PM, Edward Cree wrote:
> On 10/07/2019 16:41, Eric Dumazet wrote:
>> On 7/10/19 4:52 PM, Edward Cree wrote:
>>> Hmm, I was caught out by the call to napi_poll() actually being a local
>>> function pointer, not the static function of the same name. How did a
>>> shadow like that ever get allowed?
>>> But in that case I _really_ don't understand napi_busy_loop(); nothing
>>> in it seems to ever flush GRO, so it's relying on either
>>> (1) stuff getting flushed because the bucket runs out of space, or
>>> (2) the next napi poll after busy_poll_stop() doing the flush.
>>> What am I missing, and where exactly in napi_busy_loop() should the
>>> gro_normal_list() call go?
>> Please look at busy_poll_stop()
> I did look there, but now I've looked again and harder, and I think I get it:
> busy_poll_stop() calls napi->poll(), which (eventually, possibly in the
> subsequent poll that we schedule if rc == budget) calls napi_complete_done()
> which does the flush.
> In which case, the same applies to the napi->rx_list, which similarly gets
> handled in napi_complete_done(). So I don't think napi_busy_loop() needs a
> gro_normal_list() adding to it(?)
I advise you to try busypoll then, with TCP_RR, with say 50 usec delay in /proc/sys/net/core/busy_read
Holding a small packet in the list up to the point we call busy_poll_stop()
will basically make busypoll non working anymore.
napi_complete_done() has special behavior when busy polling is active.
>
> As a general rule, I think we need to gro_normal_list() in those places, and
> only those places, that call napi_gro_flush(). But as I mentioned in the
> patch 3/3 description, I'm still confused by the (few) drivers that call
> napi_gro_flush() themselves.
>
> -Ed
>
^ permalink raw reply
* Re: [PATCH] r8169: add enable_aspm parameter
From: Heiner Kallweit @ 2019-07-10 17:19 UTC (permalink / raw)
To: AceLan Kao
Cc: Realtek linux nic maintainers, David S. Miller, netdev,
Linux-Kernel@Vger. Kernel. Org
In-Reply-To: <CAFv23QmqjJtUD-iAwzsXg2MCNbe_p1zOcZ7C-ywG5n-iT-N-YA@mail.gmail.com>
On 10.07.2019 09:05, AceLan Kao wrote:
> Hi Heiner,
>
> I've tried and verified your PCI ASPM patches and it works well.
> I've replied the patch thread and hope this can make it get some progress.
>
Thanks for the feedback!
> BTW, do you think we can revert commit b75bb8a5b755 ("r8169: disable
> ASPM again") once the PCI ASPM patches get merged?
>
Default should remain "ASPM off" as quite a few BIOS / chip version
combinations have problems with ASPM. Interested users then can use
the new sysctl interface to switch on ASPM completely or just selected
states (e.g. L0 only).
> Best regards,
> AceLan Kao.
>
Heiner
> AceLan Kao <acelan.kao@canonical.com> 於 2019年7月9日 週二 上午11:19寫道：
>>
>> Heiner Kallweit <hkallweit1@gmail.com> 於 2019年7月9日 週二 上午2:27寫道：
>>>
>>> On 08.07.2019 08:37, AceLan Kao wrote:
>>>> We have many commits in the driver which enable and then disable ASPM
>>>> function over and over again.
>>>> commit b75bb8a5b755 ("r8169: disable ASPM again")
>>>> commit 0866cd15029b ("r8169: enable ASPM on RTL8106E")
>>>> commit 94235460f9ea ("r8169: Align ASPM/CLKREQ setting function with vendor driver")
>>>> commit aa1e7d2c31ef ("r8169: enable ASPM on RTL8168E-VL")
>>>> commit f37658da21aa ("r8169: align ASPM entry latency setting with vendor driver")
>>>> commit a99790bf5c7f ("r8169: Reinstate ASPM Support")
>>>> commit 671646c151d4 ("r8169: Don't disable ASPM in the driver")
>>>> commit 4521e1a94279 ("Revert "r8169: enable internal ASPM and clock request settings".")
>>>> commit d64ec841517a ("r8169: enable internal ASPM and clock request settings")
>>>>
>>>> This function is very important for production, and if we can't come out
>>>> a solution to make both happy, I'd suggest we add a parameter in the
>>>> driver to toggle it.
>>>>
>>> The usage of a module parameter to control ASPM is discouraged.
>>> There have been more such attempts in the past that have been declined.
>>>
>>> Pending with the PCI maintainers is a series adding ASPM control
>>> via sysfs, see here: https://www.spinics.net/lists/linux-pci/msg83228.html
>> Cool, I'll try your patches and reply on that thread.
>>
>>>
>>> Also more details than just stating "it's important for production"
>>> would have been appreciated in the commit message, e.g. which
>>> power-savings you can achieve with ASPM on which systems.
>> I should use more specific wordings rather than "important for
>> production", thanks.
>
^ permalink raw reply
* Re: [PATCH v3 bpf-next 3/4] selftests/bpf: make PT_REGS_* work in userspace
From: Andrii Nakryiko @ 2019-07-10 17:14 UTC (permalink / raw)
To: Ilya Leoshkevich
Cc: bpf, Networking, Stanislav Fomichev, Y Song, David S. Miller,
Alexei Starovoitov, Daniel Borkmann, Adrian Ratiu, david.daney
In-Reply-To: <1F8BDE1D-08C9-4C71-A281-92804455F5EF@linux.ibm.com>
On Wed, Jul 10, 2019 at 4:47 AM Ilya Leoshkevich <iii@linux.ibm.com> wrote:
>
> > Am 09.07.2019 um 19:48 schrieb Andrii Nakryiko <andrii.nakryiko@gmail.com>:
> >
> > On Tue, Jul 9, 2019 at 8:19 AM Ilya Leoshkevich <iii@linux.ibm.com> wrote:
> >>
> >> Right now, on certain architectures, these macros are usable only with
> >> kernel headers. This patch makes it possible to use them with userspace
> >> headers and, as a consequence, not only in BPF samples, but also in BPF
> >> selftests.
> >>
> >> On s390, provide the forward declaration of struct pt_regs and cast it
> >> to user_pt_regs in PT_REGS_* macros. This is necessary, because instead
> >> of the full struct pt_regs, s390 exposes only its first member
> >> user_pt_regs to userspace, and bpf_helpers.h is used with both userspace
> >> (in selftests) and kernel (in samples) headers. It was added in commit
> >> 466698e654e8 ("s390/bpf: correct broken uapi for
> >> BPF_PROG_TYPE_PERF_EVENT program type").
> >>
> >> Ditto on arm64.
> >>
> >> On x86, provide userspace versions of PT_REGS_* macros. Unlike s390 and
> >> arm64, x86 provides struct pt_regs to both userspace and kernel, however,
> >> with different member names.
> >>
> >> Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
> >> ---
> >
> > Just curious, what did you use as a reference for which register
> > corresponds to which PARM, RET, etc for different archs? I've tried to
> > look it up the other day, and it wasn't as straightforward to find as
> > I hoped for, so maybe I'm missing something obvious.
>
> For this particular change I did not have to look it up, because it all
> was already in the code, I just needed to adapt it to userspace headers.
> Normally I would google for „abi supplement“ to find this information.
> A lazy way would be to simply ask the (cross-)compiler:
>
> cat <<HERE | aarch64-linux-gnu-gcc -x c -O3 -S - -o -
> int f(int a, int b, int c, int d, int e, int f, int g, int h, int i, int j);
> int g() { return -f(1, 2, 3, 4, 5, 6, 7, 8, 9, 10); }
> HERE
Thanks for this trick! :)
>
> I’ve just double checked the supported arches, and noticed that:
>
> #define PT_REGS_PARM5(x) ((x)->uregs[4])
> for bpf_target_arm (arm-linux-gnueabihf) looks wrong:
> the 5th parameter should be passed on stack. This observation matches
> [1].
>
> #define PT_REGS_RC(x) ((x)->regs[1])
> for bpf_target_mips (mips64el-linux-gnuabi64) also looks wrong:
> the return value should be in register 2. This observation matches [2].
Now I'm glad I asked :)
>
> Since I’m not an expert on those architectures, my conclusions could be
> incorrect (e.g. becase a different ABI is normally used in practice).
> Adrian and David, could you please correct me if I’m wrong?
>
> [1] http://infocenter.arm.com/help/topic/com.arm.doc.ihi0042f/IHI0042F_aapcs.pdf
> [2] ftp://www.linux-mips.org/pub/linux/mips/doc/ABI/psABI_mips3.0.pdf
>
> >> tools/testing/selftests/bpf/bpf_helpers.h | 61 +++++++++++++++--------
> >> 1 file changed, 41 insertions(+), 20 deletions(-)
> >>
> >> diff --git a/tools/testing/selftests/bpf/bpf_helpers.h b/tools/testing/selftests/bpf/bpf_helpers.h
> >> index 73071a94769a..212ec564e5c3 100644
> >> --- a/tools/testing/selftests/bpf/bpf_helpers.h
> >> +++ b/tools/testing/selftests/bpf/bpf_helpers.h
> >> @@ -358,6 +358,7 @@ static int (*bpf_skb_adjust_room)(void *ctx, __s32 len_diff, __u32 mode,
> >>
> >> #if defined(bpf_target_x86)
> >>
> >> +#ifdef __KERNEL__
> >> #define PT_REGS_PARM1(x) ((x)->di)
> >> #define PT_REGS_PARM2(x) ((x)->si)
> >> #define PT_REGS_PARM3(x) ((x)->dx)
> >> @@ -368,19 +369,35 @@ static int (*bpf_skb_adjust_room)(void *ctx, __s32 len_diff, __u32 mode,
> >> #define PT_REGS_RC(x) ((x)->ax)
> >> #define PT_REGS_SP(x) ((x)->sp)
> >> #define PT_REGS_IP(x) ((x)->ip)
> >> +#else
> >> +#define PT_REGS_PARM1(x) ((x)->rdi)
> >> +#define PT_REGS_PARM2(x) ((x)->rsi)
> >> +#define PT_REGS_PARM3(x) ((x)->rdx)
> >> +#define PT_REGS_PARM4(x) ((x)->rcx)
> >> +#define PT_REGS_PARM5(x) ((x)->r8)
> >> +#define PT_REGS_RET(x) ((x)->rsp)
> >> +#define PT_REGS_FP(x) ((x)->rbp)
> >> +#define PT_REGS_RC(x) ((x)->rax)
> >> +#define PT_REGS_SP(x) ((x)->rsp)
> >> +#define PT_REGS_IP(x) ((x)->rip)
> >
> > Will this also work for 32-bit x86?
>
> Thanks, this is a good catch: this builds, but makes 64-bit accesses, as if it used the 64-bit
> variant of pt_regs. I will fix this.
Sounds good, thanks!
^ permalink raw reply
* Re: [PATCH] [net-next] net/mlx5e: avoid uninitialized variable use
From: Nathan Chancellor @ 2019-07-10 17:14 UTC (permalink / raw)
To: Arnd Bergmann
Cc: Saeed Mahameed, Leon Romanovsky, David S. Miller, Tariq Toukan,
Eran Ben Elisha, Boris Pismenny, netdev, linux-rdma, linux-kernel,
clang-built-linux
In-Reply-To: <20190710130638.1846846-1-arnd@arndb.de>
On Wed, Jul 10, 2019 at 03:06:25PM +0200, Arnd Bergmann wrote:
> clang points to a variable being used in an unexpected
> code path:
>
> drivers/net/ethernet/mellanox/mlx5/core/en_accel/ktls_tx.c:251:2: warning: variable 'rec_seq_sz' is used uninitialized whenever switch default is taken [-Wsometimes-uninitialized]
> default:
> ^~~~~~~
> drivers/net/ethernet/mellanox/mlx5/core/en_accel/ktls_tx.c:255:46: note: uninitialized use occurs here
> skip_static_post = !memcmp(rec_seq, &rn_be, rec_seq_sz);
> ^~~~~~~~~~
>
> From looking at the function logic, it seems that there is no
> sensible way to continue here, so just return early and hope
> for the best.
>
> Fixes: d2ead1f360e8 ("net/mlx5e: Add kTLS TX HW offload support")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
> drivers/net/ethernet/mellanox/mlx5/core/en_accel/ktls_tx.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ktls_tx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ktls_tx.c
> index 3f5f4317a22b..5c08891806f0 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ktls_tx.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ktls_tx.c
> @@ -250,6 +250,7 @@ tx_post_resync_params(struct mlx5e_txqsq *sq,
> }
> default:
> WARN_ON(1);
> + return;
> }
>
> skip_static_post = !memcmp(rec_seq, &rn_be, rec_seq_sz);
> --
> 2.20.0
>
Looks like my identical patch got picked up in net-next:
https://git.kernel.org/davem/net-next/c/1ff2f0fa450ea4e4f87793d9ed513098ec6e12be
Good to know the fix was the same.
Cheers,
Nathan
^ permalink raw reply
* [PATCH net-next] net: sched: Fix NULL-pointer dereference in tc_indr_block_ing_cmd()
From: Vlad Buslov @ 2019-07-10 17:12 UTC (permalink / raw)
To: netdev; +Cc: jhs, xiyou.wangcong, jiri, davem, pablo, saeedm, Vlad Buslov
After recent refactoring of block offlads infrastructure, indr_dev->block
pointer is dereferenced before it is verified to be non-NULL. Example stack
trace where this behavior leads to NULL-pointer dereference error when
creating vxlan dev on system with mlx5 NIC with offloads enabled:
[ 1157.852938] ==================================================================
[ 1157.866877] BUG: KASAN: null-ptr-deref in tc_indr_block_ing_cmd.isra.41+0x9c/0x160
[ 1157.880877] Read of size 4 at addr 0000000000000090 by task ip/3829
[ 1157.901637] CPU: 22 PID: 3829 Comm: ip Not tainted 5.2.0-rc6+ #488
[ 1157.914438] Hardware name: Supermicro SYS-2028TP-DECR/X10DRT-P, BIOS 2.0b 03/30/2017
[ 1157.929031] Call Trace:
[ 1157.938318] dump_stack+0x9a/0xeb
[ 1157.948362] ? tc_indr_block_ing_cmd.isra.41+0x9c/0x160
[ 1157.960262] ? tc_indr_block_ing_cmd.isra.41+0x9c/0x160
[ 1157.972082] __kasan_report+0x176/0x192
[ 1157.982513] ? tc_indr_block_ing_cmd.isra.41+0x9c/0x160
[ 1157.994348] kasan_report+0xe/0x20
[ 1158.004324] tc_indr_block_ing_cmd.isra.41+0x9c/0x160
[ 1158.015950] ? tcf_block_setup+0x430/0x430
[ 1158.026558] ? kasan_unpoison_shadow+0x30/0x40
[ 1158.037464] __tc_indr_block_cb_register+0x5f5/0xf20
[ 1158.049288] ? mlx5e_rep_indr_tc_block_unbind+0xa0/0xa0 [mlx5_core]
[ 1158.062344] ? tc_indr_block_dev_put.part.47+0x5c0/0x5c0
[ 1158.074498] ? rdma_roce_rescan_device+0x20/0x20 [ib_core]
[ 1158.086580] ? br_device_event+0x98/0x480 [bridge]
[ 1158.097870] ? strcmp+0x30/0x50
[ 1158.107578] mlx5e_nic_rep_netdevice_event+0xdd/0x180 [mlx5_core]
[ 1158.120212] notifier_call_chain+0x6d/0xa0
[ 1158.130753] register_netdevice+0x6fc/0x7e0
[ 1158.141322] ? netdev_change_features+0xa0/0xa0
[ 1158.152218] ? vxlan_config_apply+0x210/0x310 [vxlan]
[ 1158.163593] __vxlan_dev_create+0x2ad/0x520 [vxlan]
[ 1158.174770] ? vxlan_changelink+0x490/0x490 [vxlan]
[ 1158.185870] ? rcu_read_unlock+0x60/0x60 [vxlan]
[ 1158.196798] vxlan_newlink+0x99/0xf0 [vxlan]
[ 1158.207303] ? __vxlan_dev_create+0x520/0x520 [vxlan]
[ 1158.218601] ? rtnl_create_link+0x3d0/0x450
[ 1158.228900] __rtnl_newlink+0x8a7/0xb00
[ 1158.238701] ? stack_access_ok+0x35/0x80
[ 1158.248450] ? rtnl_link_unregister+0x1a0/0x1a0
[ 1158.258735] ? find_held_lock+0x6d/0xd0
[ 1158.268379] ? is_bpf_text_address+0x67/0xf0
[ 1158.278330] ? lock_acquire+0xc1/0x1f0
[ 1158.287686] ? is_bpf_text_address+0x5/0xf0
[ 1158.297449] ? is_bpf_text_address+0x86/0xf0
[ 1158.307310] ? kernel_text_address+0xec/0x100
[ 1158.317155] ? arch_stack_walk+0x92/0xe0
[ 1158.326497] ? __kernel_text_address+0xe/0x30
[ 1158.336213] ? unwind_get_return_address+0x2f/0x50
[ 1158.346267] ? create_prof_cpu_mask+0x20/0x20
[ 1158.355936] ? arch_stack_walk+0x92/0xe0
[ 1158.365117] ? stack_trace_save+0x8a/0xb0
[ 1158.374272] ? stack_trace_consume_entry+0x80/0x80
[ 1158.384226] ? match_held_lock+0x33/0x210
[ 1158.393216] ? kasan_unpoison_shadow+0x30/0x40
[ 1158.402593] rtnl_newlink+0x53/0x80
[ 1158.410925] rtnetlink_rcv_msg+0x3a5/0x600
[ 1158.419777] ? validate_linkmsg+0x400/0x400
[ 1158.428620] ? find_held_lock+0x6d/0xd0
[ 1158.437117] ? match_held_lock+0x1b/0x210
[ 1158.445760] ? validate_linkmsg+0x400/0x400
[ 1158.454642] netlink_rcv_skb+0xc7/0x1f0
[ 1158.463150] ? netlink_ack+0x470/0x470
[ 1158.471538] ? netlink_deliver_tap+0x1f3/0x5a0
[ 1158.480607] netlink_unicast+0x2ae/0x350
[ 1158.489099] ? netlink_attachskb+0x340/0x340
[ 1158.497935] ? _copy_from_iter_full+0xde/0x3b0
[ 1158.506945] ? __virt_addr_valid+0xb6/0xf0
[ 1158.515578] ? __check_object_size+0x159/0x240
[ 1158.524515] netlink_sendmsg+0x4d3/0x630
[ 1158.532879] ? netlink_unicast+0x350/0x350
[ 1158.541400] ? netlink_unicast+0x350/0x350
[ 1158.549805] sock_sendmsg+0x94/0xa0
[ 1158.557561] ___sys_sendmsg+0x49d/0x570
[ 1158.565625] ? copy_msghdr_from_user+0x210/0x210
[ 1158.574457] ? __fput+0x1e2/0x330
[ 1158.581948] ? __kasan_slab_free+0x130/0x180
[ 1158.590407] ? kmem_cache_free+0xb6/0x2d0
[ 1158.598574] ? mark_lock+0xc7/0x790
[ 1158.606177] ? task_work_run+0xcf/0x100
[ 1158.614165] ? exit_to_usermode_loop+0x102/0x110
[ 1158.622954] ? __lock_acquire+0x963/0x1ee0
[ 1158.631199] ? lockdep_hardirqs_on+0x260/0x260
[ 1158.639777] ? match_held_lock+0x1b/0x210
[ 1158.647918] ? lockdep_hardirqs_on+0x260/0x260
[ 1158.656501] ? match_held_lock+0x1b/0x210
[ 1158.664643] ? __fget_light+0xa6/0xe0
[ 1158.672423] ? __sys_sendmsg+0xd2/0x150
[ 1158.680334] __sys_sendmsg+0xd2/0x150
[ 1158.688063] ? __ia32_sys_shutdown+0x30/0x30
[ 1158.696435] ? lock_downgrade+0x2e0/0x2e0
[ 1158.704541] ? mark_held_locks+0x1a/0x90
[ 1158.712611] ? mark_held_locks+0x1a/0x90
[ 1158.720619] ? do_syscall_64+0x1e/0x2c0
[ 1158.728530] do_syscall_64+0x78/0x2c0
[ 1158.736254] entry_SYSCALL_64_after_hwframe+0x49/0xbe
[ 1158.745414] RIP: 0033:0x7f62d505cb87
[ 1158.753070] Code: 64 89 02 48 c7 c0 ff ff ff ff eb b9 0f 1f 80 00 00 00 00 8b 05 6a 2b 2c 00 48 63 d2 48 63 ff 85 c0 75 18 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 59 f3 c3 0f 1f 80 00 00[87/1817]
48 89 f3 48
[ 1158.780924] RSP: 002b:00007fffd9832268 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[ 1158.793204] RAX: ffffffffffffffda RBX: 000000005d26048f RCX: 00007f62d505cb87
[ 1158.805111] RDX: 0000000000000000 RSI: 00007fffd98322d0 RDI: 0000000000000003
[ 1158.817055] RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000006
[ 1158.828987] R10: 00007f62d50ce260 R11: 0000000000000246 R12: 0000000000000001
[ 1158.840909] R13: 000000000067e540 R14: 0000000000000000 R15: 000000000067ed20
[ 1158.852873] ==================================================================
Introduce new function tcf_block_non_null_shared() that verifies block
pointer before dereferencing it to obtain index. Use the function in
tc_indr_block_ing_cmd() to prevent NULL pointer dereference.
Fixes: 955bcb6ea0df ("drivers: net: use flow block API")
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
---
include/net/pkt_cls.h | 10 ++++++++++
net/sched/cls_api.c | 2 +-
2 files changed, 11 insertions(+), 1 deletion(-)
diff --git a/include/net/pkt_cls.h b/include/net/pkt_cls.h
index b03d466182db..841faadceb6e 100644
--- a/include/net/pkt_cls.h
+++ b/include/net/pkt_cls.h
@@ -60,6 +60,11 @@ static inline bool tcf_block_shared(struct tcf_block *block)
return block->index;
}
+static inline bool tcf_block_non_null_shared(struct tcf_block *block)
+{
+ return block && block->index;
+}
+
static inline struct Qdisc *tcf_block_q(struct tcf_block *block)
{
WARN_ON(tcf_block_shared(block));
@@ -84,6 +89,11 @@ static inline bool tcf_block_shared(struct tcf_block *block)
return false;
}
+static inline bool tcf_block_non_null_shared(struct tcf_block *block)
+{
+ return false;
+}
+
static inline
int tcf_block_get(struct tcf_block **p_block,
struct tcf_proto __rcu **p_filter_chain, struct Qdisc *q,
diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
index 638c1bc1ea1b..278014e26aec 100644
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -684,7 +684,7 @@ static void tc_indr_block_ing_cmd(struct tc_indr_block_dev *indr_dev,
.command = command,
.binder_type = FLOW_BLOCK_BINDER_TYPE_CLSACT_INGRESS,
.net = dev_net(indr_dev->dev),
- .block_shared = tcf_block_shared(indr_dev->block),
+ .block_shared = tcf_block_non_null_shared(indr_dev->block),
};
INIT_LIST_HEAD(&bo.cb_list);
--
2.21.0
^ permalink raw reply related
* Re: [PATCH v3 net-next 19/19] ionic: Add basic devlink interface
From: Shannon Nelson @ 2019-07-10 17:06 UTC (permalink / raw)
To: Jiri Pirko; +Cc: netdev
In-Reply-To: <20190710064819.GC2282@nanopsycho>
On 7/9/19 11:48 PM, Jiri Pirko wrote:
> Tue, Jul 09, 2019 at 09:13:53PM CEST, snelson@pensando.io wrote:
>> On 7/8/19 11:56 PM, Jiri Pirko wrote:
>>> Tue, Jul 09, 2019 at 12:58:00AM CEST, snelson@pensando.io wrote:
>>>> On 7/8/19 1:03 PM, Jiri Pirko wrote:
>>>>> Mon, Jul 08, 2019 at 09:58:09PM CEST, snelson@pensando.io wrote:
>>>>>> If I'm not mistaken, the alloc is only allocating enough for a pointer, not
>>>>>> the whole per device struct, and a few lines down from here the pointer to
>>>>>> the new devlink struct is assigned to ionic->dl. This was based on what I
>>>>>> found in the qed driver's qed_devlink_register(), and it all seems to work.
>>>>> I'm not saying your code won't work. What I say is that you should have
>>>>> a struct for device that would be allocated by devlink_alloc()
>>>> Is there a particular reason why? I appreciate that devlink_alloc() can give
>>>> you this device specific space, just as alloc_etherdev_mq() can, but is there
>>> Yes. Devlink manipulates with the whole device. However,
>>> alloc_etherdev_mq() allocates only net_device. These are 2 different
>>> things. devlink port relates 1:1 to net_device. However, devlink
>>> instance can have multiple ports. What I say is do it correctly.
>> So what you are saying is that anyone who wants to add even the smallest
>> devlink feature to their driver needs to rework their basic device memory
>> setup to do it the devlink way. I can see where some folks may have a
>> problem with this.
> It's just about having a structure to hold device data. You don't have
> to rework anything, just add this small one.
Well, there's a bit of logic rework to and a little data twiddling - not
too bad in our case. Others may not be thrilled depending on how
they've already implemented their drivers.
>>>>> The ionic struct should be associated with devlink_port. That you are
>>>>> missing too.
>>>> We don't support any of devlink_port features at this point, just the simple
>>>> device information.
>>> No problem, you can still register devlink_port. You don't have to do
>>> much in order to do so.
>> Is there any write-up to help guide developers new to devlink in using the
>> interface correctly? I haven't found much yet, but perhaps I've missed
>> something. The manpages are somewhat useful in showing what the user might
>> do, but they really don't help much in guiding the developer through these
>> details.
> That is not job of a manpage. See the rest of the code to get inspired.
>
Sure, we should all be able to poke through the code and figure out the
basics - "use the Force, read the source" - but as software engineers we
should be including some bits of documentation to help those new to the
feature to steer away from pitfalls and use the feature correctly.
We're all busy with our own projects and only have limited time to dig
into and understand someone else's code; if there's not a guide, we'll
do what we can to get it working and then move on, with no guarantee
that we followed the original intent.
There's a Documentation page on the devlink-health feature, and a brief
bit on devlink-params, but I haven't seen anything yet that spells out
the "proper" way to use the devlink framework. Of course, the
open-source spirit is for me to scratch my own itch and take care of the
need myself: I'd be happy to get a brief doc started, but if the
original developers can take a few minutes to at least sketch some notes
down about important bits like "the device struct should be associated
with devlink_port" and why it should, then we have a chance at saving a
lot of other people's time, and perhaps we can fill out the details
correctly and not miss something important.
sln
^ permalink raw reply
* Re: [RFC PATCH net-next 0/3] net: batched receive in GRO path
From: Edward Cree @ 2019-07-10 16:47 UTC (permalink / raw)
To: Eric Dumazet, Paolo Abeni, David Miller; +Cc: netdev
In-Reply-To: <1735314f-3c6a-45fc-0270-b90cc4d5d6ba@gmail.com>
On 10/07/2019 16:41, Eric Dumazet wrote:
> On 7/10/19 4:52 PM, Edward Cree wrote:
>> Hmm, I was caught out by the call to napi_poll() actually being a local
>> function pointer, not the static function of the same name. How did a
>> shadow like that ever get allowed?
>> But in that case I _really_ don't understand napi_busy_loop(); nothing
>> in it seems to ever flush GRO, so it's relying on either
>> (1) stuff getting flushed because the bucket runs out of space, or
>> (2) the next napi poll after busy_poll_stop() doing the flush.
>> What am I missing, and where exactly in napi_busy_loop() should the
>> gro_normal_list() call go?
> Please look at busy_poll_stop()
I did look there, but now I've looked again and harder, and I think I get it:
busy_poll_stop() calls napi->poll(), which (eventually, possibly in the
subsequent poll that we schedule if rc == budget) calls napi_complete_done()
which does the flush.
In which case, the same applies to the napi->rx_list, which similarly gets
handled in napi_complete_done(). So I don't think napi_busy_loop() needs a
gro_normal_list() adding to it(?)
As a general rule, I think we need to gro_normal_list() in those places, and
only those places, that call napi_gro_flush(). But as I mentioned in the
patch 3/3 description, I'm still confused by the (few) drivers that call
napi_gro_flush() themselves.
-Ed
^ permalink raw reply
* Re: [PATCH v2 6/7] dt-bindings: net: realtek: Add property to configure LED mode
From: Florian Fainelli @ 2019-07-10 16:28 UTC (permalink / raw)
To: Rob Herring, Matthias Kaehlcke, Andrew Lunn, Heiner Kallweit
Cc: David S . Miller, Mark Rutland, netdev, devicetree,
linux-kernel@vger.kernel.org, Douglas Anderson
In-Reply-To: <CAL_JsqL_AU+JV0c2mNbXiPh2pvfYbPbLV-2PHHX0hC3vUH4QWg@mail.gmail.com>
On 7/10/19 8:55 AM, Rob Herring wrote:
> On Wed, Jul 3, 2019 at 5:23 PM Matthias Kaehlcke <mka@chromium.org> wrote:
>>
>> Hi Florian,
>>
>> On Wed, Jul 03, 2019 at 02:37:47PM -0700, Florian Fainelli wrote:
>>> On 7/3/19 12:37 PM, Matthias Kaehlcke wrote:
>>>> The LED behavior of some Realtek PHYs is configurable. Add the
>>>> property 'realtek,led-modes' to specify the configuration of the
>>>> LEDs.
>>>>
>>>> Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
>>>> ---
>>>> Changes in v2:
>>>> - patch added to the series
>>>> ---
>>>> .../devicetree/bindings/net/realtek.txt | 9 +++++++++
>>>> include/dt-bindings/net/realtek.h | 17 +++++++++++++++++
>>>> 2 files changed, 26 insertions(+)
>>>> create mode 100644 include/dt-bindings/net/realtek.h
>>>>
>>>> diff --git a/Documentation/devicetree/bindings/net/realtek.txt b/Documentation/devicetree/bindings/net/realtek.txt
>>>> index 71d386c78269..40b0d6f9ee21 100644
>>>> --- a/Documentation/devicetree/bindings/net/realtek.txt
>>>> +++ b/Documentation/devicetree/bindings/net/realtek.txt
>>>> @@ -9,6 +9,12 @@ Optional properties:
>>>>
>>>> SSC is only available on some Realtek PHYs (e.g. RTL8211E).
>>>>
>>>> +- realtek,led-modes: LED mode configuration.
>>>> +
>>>> + A 0..3 element vector, with each element configuring the operating
>>>> + mode of an LED. Omitted LEDs are turned off. Allowed values are
>>>> + defined in "include/dt-bindings/net/realtek.h".
>>>
>>> This should probably be made more general and we should define LED modes
>>> that makes sense regardless of the PHY device, introduce a set of
>>> generic functions for validating and then add new function pointer for
>>> setting the LED configuration to the PHY driver. This would allow to be
>>> more future proof where each PHY driver could expose standard LEDs class
>>> devices to user-space, and it would also allow facilities like: ethtool
>>> -p to plug into that.
>>>
>>> Right now, each driver invents its own way of configuring LEDs, that
>>> does not scale, and there is not really a good reason for that other
>>> than reviewing drivers in isolation and therefore making it harder to
>>> extract the commonality. Yes, I realize that since you are the latest
>>> person submitting something in that area, you are being selected :)
>
> I agree.
>
>> I see the merit of your proposal to come up with a generic mechanism
>> to configure Ethernet LEDs, however I can't justify spending much of
>> my work time on this. If it is deemed useful I'm happy to send another
>> version of the current patchset that addresses the reviewer's comments,
>> but if the implementation of a generic LED configuration interface is
>> a requirement I will have to abandon at least the LED configuration
>> part of this series.
>
> Can you at least define a common binding for this. Maybe that's just
> removing 'realtek'. While the kernel side can evolve to a common
> infrastructure, the DT bindings can't.
That would be a great start, and that is actually what I had in mind
(should have been more specific), I was not going to have you Matthias
do the grand slam and convert all this LED configuration into the LEDs
class etc. that would not be fair.
It seems to be that we can fairly easily agree on a common binding for
LED configuration, I would define something along those lines to be
flexible:
phy-led-configuration = <LED_NUM_MASK LED_CFG_MASK>;
where LED_NUM_MASK is one of:
0 -> link
1 -> activity
2 -> speed
that way you can define single/dual/triple LED configurations by
updating the bitmask.
LED_CFG_MASK is one of:
0 -> LED_CFG_10
1 -> LED_CFG_100
2 -> LED_CFG_1000
(let's assume 1Gbps or less for now)
or this can be combined in a single cell with a left shift.
Andrew, Heiner, do you see that approach working correctly and scaling
appropriately?
--
Florian
^ permalink raw reply
* Re: [PATCH 00/12] treewide: Fix GENMASK misuses
From: Joe Perches @ 2019-07-10 16:01 UTC (permalink / raw)
To: Russell King - ARM Linux admin, Johannes Berg
Cc: Andrew Morton, Patrick Venture, Nancy Yuen, Benjamin Fair,
Andrew Jeffery, openbmc, linux-kernel, linux-aspeed,
linux-arm-kernel, linux-amlogic, netdev, linux-mediatek,
linux-stm32, linux-wireless, linux-media, linux-iio, devel,
alsa-devel, linux-mmc, dri-devel
In-Reply-To: <b9c3b83c9be50286062ae8cefd5d38e2baa0fb22.camel@perches.com>
On Wed, 2019-07-10 at 08:45 -0700, Joe Perches wrote:
> On Wed, 2019-07-10 at 10:43 +0100, Russell King - ARM Linux admin wrote:
> > On Wed, Jul 10, 2019 at 11:17:31AM +0200, Johannes Berg wrote:
> > > On Tue, 2019-07-09 at 22:04 -0700, Joe Perches wrote:
> > > > These GENMASK uses are inverted argument order and the
> > > > actual masks produced are incorrect. Fix them.
> > > >
> > > > Add checkpatch tests to help avoid more misuses too.
> > > >
> > > > Joe Perches (12):
> > > > checkpatch: Add GENMASK tests
> > >
> > > IMHO this doesn't make a lot of sense as a checkpatch test - just throw
> > > in a BUILD_BUG_ON()?
>
> I tried that.
>
> It'd can't be done as it's used in declarations
> and included in asm files and it uses the UL()
> macro.
>
> I also tried just making it do the right thing
> whatever the argument order.
I forgot.
I also made all those arguments when it was
introduced in 2013.
https://lore.kernel.org/patchwork/patch/414248/
> Oh well.
yeah.
^ permalink raw reply
* Re: [PATCH v2 bpf] selftests/bpf: fix bpf_target_sparc check
From: Andrii Nakryiko @ 2019-07-10 15:58 UTC (permalink / raw)
To: Ilya Leoshkevich; +Cc: bpf, Networking
In-Reply-To: <20190710115654.44841-1-iii@linux.ibm.com>
On Wed, Jul 10, 2019 at 4:57 AM Ilya Leoshkevich <iii@linux.ibm.com> wrote:
>
> bpf_helpers.h fails to compile on sparc: the code should be checking
> for defined(bpf_target_sparc), but checks simply for bpf_target_sparc.
>
> Also change #ifdef bpf_target_powerpc to #if defined() for consistency.
>
> Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
> ---
Thanks!
Acked-by: Andrii Nakryiko <andriin@fb.com>
>
> v1->v2: bpf_target_powerpc change
>
> tools/testing/selftests/bpf/bpf_helpers.h | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/tools/testing/selftests/bpf/bpf_helpers.h b/tools/testing/selftests/bpf/bpf_helpers.h
> index 5f6f9e7aba2a..0214797518ce 100644
> --- a/tools/testing/selftests/bpf/bpf_helpers.h
> +++ b/tools/testing/selftests/bpf/bpf_helpers.h
> @@ -440,10 +440,10 @@ static int (*bpf_skb_adjust_room)(void *ctx, __s32 len_diff, __u32 mode,
>
> #endif
>
> -#ifdef bpf_target_powerpc
> +#if defined(bpf_target_powerpc)
Oh, yeah, that mix of #ifdef and #if definitely threw me off. I prefer
consistency, so thanks for this update!
> #define BPF_KPROBE_READ_RET_IP(ip, ctx) ({ (ip) = (ctx)->link; })
> #define BPF_KRETPROBE_READ_RET_IP BPF_KPROBE_READ_RET_IP
> -#elif bpf_target_sparc
> +#elif defined(bpf_target_sparc)
> #define BPF_KPROBE_READ_RET_IP(ip, ctx) ({ (ip) = PT_REGS_RET(ctx); })
> #define BPF_KRETPROBE_READ_RET_IP BPF_KPROBE_READ_RET_IP
> #else
> --
> 2.21.0
>
^ permalink raw reply
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