* Re: [PATCH v4 4/7] lib/hexdump.c: Replace ascii bool in hex_dump_to_buffer with flags
From: Alastair D'Silva @ 2019-06-26 1:27 UTC (permalink / raw)
To: Joe Perches
Cc: Jani Nikula, Joonas Lahtinen, Rodrigo Vivi, David Airlie,
Daniel Vetter, Dan Carpenter, Karsten Keil, Jassi Brar,
Tom Lendacky, David S. Miller, Jose Abreu, Kalle Valo,
Stanislaw Gruszka, Benson Leung, Enric Balletbo i Serra,
James E.J. Bottomley, Martin K. Petersen, Greg Kroah-Hartman,
Alexander Viro, Petr Mladek, Sergey Senozhatsky, Steven Rostedt,
David Laight, Andrew Morton, intel-gfx, dri-devel, linux-kernel,
netdev, ath10k, linux-wireless, linux-scsi, linux-fbdev, devel,
linux-fsdevel
In-Reply-To: <4ba3b835fb3675ea685390903a082bf8b7f9e955.camel@perches.com>
On Mon, 2019-06-24 at 22:19 -0700, Joe Perches wrote:
> On Tue, 2019-06-25 at 15:06 +1000, Alastair D'Silva wrote:
> > The change actions Jani's suggestion:
> > https://lkml.org/lkml/2019/6/20/343
>
> I suggest not changing any of the existing uses of
> hex_dump_to_buffer and only use hex_dump_to_buffer_ext
> when necessary for your extended use cases.
>
>
I disagree, adding a wrapper for the benefit of avoiding touching a
handful of call sites that are easily amended would be adding technical
debt.
--
Alastair D'Silva mob: 0423 762 819
skype: alastair_dsilva
Twitter: @EvilDeece
blog: http://alastair.d-silva.org
^ permalink raw reply
* Re: [PATCH v4 5/7] lib/hexdump.c: Allow multiple groups to be separated by lines '|'
From: Alastair D'Silva @ 2019-06-26 1:28 UTC (permalink / raw)
To: Joe Perches
Cc: Jani Nikula, Joonas Lahtinen, Rodrigo Vivi, David Airlie,
Daniel Vetter, Dan Carpenter, Karsten Keil, Jassi Brar,
Tom Lendacky, David S. Miller, Jose Abreu, Kalle Valo,
Stanislaw Gruszka, Benson Leung, Enric Balletbo i Serra,
James E.J. Bottomley, Martin K. Petersen, Greg Kroah-Hartman,
Alexander Viro, Petr Mladek, Sergey Senozhatsky, Steven Rostedt,
David Laight, Andrew Morton, intel-gfx, dri-devel, linux-kernel,
netdev, ath10k, linux-wireless, linux-scsi, linux-fbdev, devel,
linux-fsdevel
In-Reply-To: <c364c36338d385eba60c523828ad8995c792ae4d.camel@perches.com>
On Mon, 2019-06-24 at 22:37 -0700, Joe Perches wrote:
> On Tue, 2019-06-25 at 13:17 +1000, Alastair D'Silva wrote:
> > From: Alastair D'Silva <alastair@d-silva.org>
> >
> > With the wider display format, it can become hard to identify how
> > many
> > bytes into the line you are looking at.
> >
> > The patch adds new flags to hex_dump_to_buffer() and
> > print_hex_dump() to
> > print vertical lines to separate every N groups of bytes.
> >
> > eg.
> > buf:00000000: 454d414e 43415053|4e495f45
> > 00584544 NAMESPAC|E_INDEX.
> > buf:00000010: 00000000 00000002|00000000
> > 00000000 ........|........
> >
> > Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
> > ---
> > include/linux/printk.h | 3 +++
> > lib/hexdump.c | 59 ++++++++++++++++++++++++++++++++++++
> > ------
> > 2 files changed, 54 insertions(+), 8 deletions(-)
> >
> > diff --git a/include/linux/printk.h b/include/linux/printk.h
> []
> > @@ -485,6 +485,9 @@ enum {
> >
> > #define HEXDUMP_ASCII BIT(0)
> > #define HEXDUMP_SUPPRESS_REPEATED BIT(1)
> > +#define HEXDUMP_2_GRP_LINES BIT(2)
> > +#define HEXDUMP_4_GRP_LINES BIT(3)
> > +#define HEXDUMP_8_GRP_LINES BIT(4)
>
> These aren't really bits as only one value should be set
> as 8 overrides 4 and 4 overrides 2.
This should be the other way around, as we should be emitting alternate
seperators based on the smallest grouping (2 implies 4 and 8, and 4
implies 8). I'll fix the logic.
I can't come up with a better way to represent these without making the
API more complex, if you have a suggestion, I'm happy to hear it.
>
> I would also expect this to be a value of 2 in your above
> example, rather than 8. It's described as groups not bytes.
>
> The example is showing a what would normally be a space ' '
> separator as a vertical bar '|' every 2nd grouping.
>
The above example shows a group size of 4 bytes, and
HEXDUMP_2_GRP_LINES set, with 2 groups being 8 bytes.
I'll make that clearer in the commit message.
--
Alastair D'Silva mob: 0423 762 819
skype: alastair_dsilva
Twitter: @EvilDeece
blog: http://alastair.d-silva.org
^ permalink raw reply
* Re: [PATCH bpf-next v6 0/2] bpf: Allow bpf_skb_event_output for more prog types
From: Song Liu @ 2019-06-26 1:35 UTC (permalink / raw)
To: allanzhang
Cc: Alexei Starovoitov, Daniel Borkmann, Martin KaFai Lau, Song Liu,
Yonghong Song, David S. Miller, Networking, bpf, open list
In-Reply-To: <20190626003852.163986-1-allanzhang@google.com>
On Tue, Jun 25, 2019 at 5:39 PM allanzhang <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.
>
> v2 changes:
> Reformating log message.
>
> v3 changes:
> Reformating log message.
>
> v4 changes:
> Reformating log message.
>
> v5 changes:
> Fix typos, reformat comments in event_output.c, move revision history to
> cover letter.
>
> v6 changes:
> fix Signed-off-by, fix fixup map creation.
>
> allanzhang (2):
I guess you manually fixed the name in the other two patches, but forgot
this one. You can fix it in your .gitconfig file. Make sure to get the proper
capital letters.
Also, please run ./scripts/checkpatch.pl on your patch files. This will help
you find a lot of issues.
Thanks,
Song
> bpf: Allow bpf_skb_event_output for a few prog types
> 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 v4 net-next 1/4] net: core: page_pool: add user cnt preventing pool deletion
From: Willem de Bruijn @ 2019-06-26 1:36 UTC (permalink / raw)
To: Ivan Khoronzhuk
Cc: David Miller, grygorii.strashko, hawk, brouer, saeedm, leon,
Alexei Starovoitov, linux-kernel, linux-omap, xdp-newbies,
ilias.apalodimas, Network Development, Daniel Borkmann,
jakub.kicinski, John Fastabend
In-Reply-To: <20190625175948.24771-2-ivan.khoronzhuk@linaro.org>
On Tue, Jun 25, 2019 at 2:00 PM Ivan Khoronzhuk
<ivan.khoronzhuk@linaro.org> wrote:
>
> Add user counter allowing to delete pool only when no users.
> It doesn't prevent pool from flush, only prevents freeing the
> pool instance. Helps when no need to delete the pool and now
> it's user responsibility to free it by calling page_pool_free()
> while destroying procedure. It also makes to use page_pool_free()
> explicitly, not fully hidden in xdp unreg, which looks more
> correct after page pool "create" routine.
>
> Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
> ---
> diff --git a/include/net/page_pool.h b/include/net/page_pool.h
> index f07c518ef8a5..1ec838e9927e 100644
> --- a/include/net/page_pool.h
> +++ b/include/net/page_pool.h
> @@ -101,6 +101,7 @@ struct page_pool {
> struct ptr_ring ring;
>
> atomic_t pages_state_release_cnt;
> + atomic_t user_cnt;
refcount_t?
> };
>
> struct page *page_pool_alloc_pages(struct page_pool *pool, gfp_t gfp);
> @@ -183,6 +184,12 @@ static inline dma_addr_t page_pool_get_dma_addr(struct page *page)
> return page->dma_addr;
> }
>
> +/* used to prevent pool from deallocation */
> +static inline void page_pool_get(struct page_pool *pool)
> +{
> + atomic_inc(&pool->user_cnt);
> +}
> +
> static inline bool is_page_pool_compiled_in(void)
> {
> #ifdef CONFIG_PAGE_POOL
> diff --git a/net/core/page_pool.c b/net/core/page_pool.c
> index b366f59885c1..169b0e3c870e 100644
> --- a/net/core/page_pool.c
> +++ b/net/core/page_pool.c
> @@ -48,6 +48,7 @@ static int page_pool_init(struct page_pool *pool,
> return -ENOMEM;
>
> atomic_set(&pool->pages_state_release_cnt, 0);
> + atomic_set(&pool->user_cnt, 0);
>
> if (pool->p.flags & PP_FLAG_DMA_MAP)
> get_device(pool->p.dev);
> @@ -70,6 +71,8 @@ struct page_pool *page_pool_create(const struct page_pool_params *params)
> kfree(pool);
> return ERR_PTR(err);
> }
> +
> + page_pool_get(pool);
> return pool;
> }
> EXPORT_SYMBOL(page_pool_create);
> @@ -356,6 +359,10 @@ static void __warn_in_flight(struct page_pool *pool)
>
> void __page_pool_free(struct page_pool *pool)
> {
> + /* free only if no users */
> + if (!atomic_dec_and_test(&pool->user_cnt))
> + return;
> +
> WARN(pool->alloc.count, "API usage violation");
> WARN(!ptr_ring_empty(&pool->ring), "ptr_ring is not empty");
>
> diff --git a/net/core/xdp.c b/net/core/xdp.c
> index 829377cc83db..04bdcd784d2e 100644
> --- a/net/core/xdp.c
> +++ b/net/core/xdp.c
> @@ -372,6 +372,9 @@ int xdp_rxq_info_reg_mem_model(struct xdp_rxq_info *xdp_rxq,
>
> mutex_unlock(&mem_id_lock);
>
> + if (type == MEM_TYPE_PAGE_POOL)
> + page_pool_get(xdp_alloc->page_pool);
> +
need an analogous page_pool_put in xdp_rxq_info_unreg_mem_model? mlx5
does not use that inverse function, but intel drivers do.
> trace_mem_connect(xdp_alloc, xdp_rxq);
> return 0;
> err:
> --
> 2.17.1
>
^ permalink raw reply
* [PATCHv2 iproute2] ip/iptoken: fix dump error when ipv6 disabled
From: Hangbin Liu @ 2019-06-26 1:44 UTC (permalink / raw)
To: netdev
Cc: Daniel Borkmann, Phil Sutter, Stephen Hemminger, David Ahern,
Andrea Claudi, Hangbin Liu
In-Reply-To: <20190625093550.7804-1-liuhangbin@gmail.com>
When we disable IPv6 from the start up (ipv6.disable=1), there will be
no IPv6 route info in the dump message. If we return -1 when
ifi->ifi_family != AF_INET6, we will get error like
$ ip token list
Dump terminated
which will make user feel confused. There is no need to return -1 if the
dump message not match. Return 0 is enough.
v2: do not combine all the conditions together.
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
---
ip/iptoken.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/ip/iptoken.c b/ip/iptoken.c
index f1194c3e..9f356890 100644
--- a/ip/iptoken.c
+++ b/ip/iptoken.c
@@ -60,9 +60,9 @@ static int print_token(struct nlmsghdr *n, void *arg)
return -1;
if (ifi->ifi_family != AF_INET6)
- return -1;
+ return 0;
if (ifi->ifi_index == 0)
- return -1;
+ return 0;
if (ifindex > 0 && ifi->ifi_index != ifindex)
return 0;
if (ifi->ifi_flags & (IFF_LOOPBACK | IFF_NOARP))
--
2.19.2
^ permalink raw reply related
* Re: [PATCH RFC net-next 1/5] net: dsa: mt7530: Convert to PHYLINK API
From: Andrew Lunn @ 2019-06-26 1:52 UTC (permalink / raw)
To: Vladimir Oltean
Cc: Russell King - ARM Linux admin, René van Dorst, sean.wang,
Florian Fainelli, David S. Miller, matthias.bgg, Vivien Didelot,
frank-w, netdev, linux-mediatek, linux-mips
In-Reply-To: <CA+h21hrsosGVQczMWy1+WfyNGZCpeMFerUwvWb-z+TTjrSOP1Q@mail.gmail.com>
On Wed, Jun 26, 2019 at 02:13:25AM +0300, Vladimir Oltean wrote:
> On Wed, 26 Jun 2019 at 02:10, Vladimir Oltean <olteanv@gmail.com> wrote:
> >
> > On Wed, 26 Jun 2019 at 01:58, Russell King - ARM Linux admin
> > <linux@armlinux.org.uk> wrote:
> > >
> > > On Wed, Jun 26, 2019 at 01:14:59AM +0300, Vladimir Oltean wrote:
> > > > On Wed, 26 Jun 2019 at 00:53, Russell King - ARM Linux admin
> > > > <linux@armlinux.org.uk> wrote:
> > > > >
> > > > > On Tue, Jun 25, 2019 at 11:24:01PM +0300, Vladimir Oltean wrote:
> > > > > > Hi Russell,
> > > > > >
> > > > > > On 6/24/19 6:39 PM, Russell King - ARM Linux admin wrote:
> > > > > > > This should be removed - state->link is not for use in mac_config.
> > > > > > > Even in fixed mode, the link can be brought up/down by means of a
> > > > > > > gpio, and this should be dealt with via the mac_link_* functions.
> > > > > > >
> > > > > >
> > > > > > What do you mean exactly that state->link is not for use, is that true in
> > > > > > general?
> > > > >
> > > > > Yes. mac_config() should not touch it; it is not always in a defined
> > > > > state. For example, if you set modes via ethtool (the
> > > > > ethtool_ksettings_set API) then state->link will probably contain
> > > > > zero irrespective of the true link state.
> > > > >
> > > >
> > > > Experimentally, state->link is zero at the same time as state->speed
> > > > is -1, so just ignoring !state->link made sense. This is not in-band
> > > > AN. What is your suggestion? Should I proceed to try and configure the
> > > > MAC for SPEED_UNKNOWN?
> > >
> > > What would you have done with a PHY when the link is down, what speed
> > > would you have configured in the phylib adjust_link callback? phylib
> > > also sets SPEED_UNKNOWN/DUPLEX_UNKNOWN when the link is down.
> > >
> >
> > With phylib, I'd make the driver ignore the speed and do nothing.
> > With phylink, I'd make the core not call mac_config.
> > But what happened is I saw phylink call mac_config anyway, said
> > 'weird' and proceeded to ignore it as I would have for phylib.
> > I'm just not understanding your position - it seems like you're
> > implying there's a bug in phylink and the function call with
> > MLO_AN_FIXED, state->link=0 and state->speed=-1 should not have taken
>
> I meant MLO_AN_PHY, sorry.
The MAC could go into a low power mode.
Andrew
^ permalink raw reply
* Re: [PATCH] net: phylink: further documentation clarifications
From: Florian Fainelli @ 2019-06-26 2:16 UTC (permalink / raw)
To: Russell King, Andrew Lunn, Heiner Kallweit; +Cc: David S. Miller, netdev
In-Reply-To: <E1hfi09-0007Zs-Vb@rmk-PC.armlinux.org.uk>
On 6/25/2019 2:44 AM, Russell King wrote:
> Clarify the validate() behaviour in a few cases which weren't mentioned
> in the documentation, but which are necessary for users to get the
> correct behaviour.
>
> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
--
Florian
^ permalink raw reply
* Re: [PATCH v4 net-next 3/4] net: ethernet: ti: davinci_cpdma: return handler status
From: Willem de Bruijn @ 2019-06-26 2:17 UTC (permalink / raw)
To: Ivan Khoronzhuk
Cc: David Miller, grygorii.strashko, hawk, brouer, saeedm, leon,
Alexei Starovoitov, linux-kernel, linux-omap, xdp-newbies,
ilias.apalodimas, Network Development, Daniel Borkmann,
jakub.kicinski, John Fastabend
In-Reply-To: <20190625175948.24771-4-ivan.khoronzhuk@linaro.org>
On Tue, Jun 25, 2019 at 2:00 PM Ivan Khoronzhuk
<ivan.khoronzhuk@linaro.org> wrote:
>
> This change is needed to return flush status of rx handler for
> flushing redirected xdp frames after processing channel packets.
> Do it as separate patch for simplicity.
>
> Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
> @@ -602,7 +605,8 @@ static int cpsw_tx_mq_poll(struct napi_struct *napi_tx, int budget)
> else
> cur_budget = txv->budget;
>
> - num_tx += cpdma_chan_process(txv->ch, cur_budget);
> + cpdma_chan_process(txv->ch, &cur_budget);
> + num_tx += cur_budget;
Less code change to add a new argument int *flush to communicate the
new state and leave the existing argument and return values as is?
^ permalink raw reply
* Re: [PATCH bpf-next 1/2] libbpf: add perf buffer reading API
From: Song Liu @ 2019-06-26 2:18 UTC (permalink / raw)
To: Andrii Nakryiko
Cc: Andrii Nakryiko, Alexei Starovoitov, Daniel Borkmann, bpf,
Networking, Kernel Team
In-Reply-To: <20190625232601.3227055-2-andriin@fb.com>
On Tue, Jun 25, 2019 at 4:28 PM Andrii Nakryiko <andriin@fb.com> wrote:
>
> BPF_MAP_TYPE_PERF_EVENT_ARRAY map is often used to send data from BPF program
> to user space for additional processing. libbpf already has very low-level API
> to read single CPU perf buffer, bpf_perf_event_read_simple(), but it's hard to
> use and requires a lot of code to set everything up. This patch adds
> perf_buffer abstraction on top of it, abstracting setting up and polling
> per-CPU logic into simple and convenient API, similar to what BCC provides.
>
> perf_buffer__new() sets up per-CPU ring buffers and updates corresponding BPF
> map entries. It accepts two user-provided callbacks: one for handling raw
> samples and one for get notifications of lost samples due to buffer overflow.
>
> perf_buffer__poll() is used to fetch ring buffer data across all CPUs,
> utilizing epoll instance.
>
> perf_buffer__free() does corresponding clean up and unsets FDs from BPF map.
>
> All APIs are not thread-safe. User should ensure proper locking/coordination if
> used in multi-threaded set up.
>
> Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Overall looks good. Some nit below.
> ---
> tools/lib/bpf/libbpf.c | 282 +++++++++++++++++++++++++++++++++++++++
> tools/lib/bpf/libbpf.h | 12 ++
> tools/lib/bpf/libbpf.map | 5 +-
> 3 files changed, 298 insertions(+), 1 deletion(-)
[...]
> +struct perf_buffer *perf_buffer__new(struct bpf_map *map, size_t page_cnt,
> + perf_buffer_sample_fn sample_cb,
> + perf_buffer_lost_fn lost_cb, void *ctx)
> +{
> + char msg[STRERR_BUFSIZE];
> + struct perf_buffer *pb;
> + int err, cpu;
> +
> + if (bpf_map__def(map)->type != BPF_MAP_TYPE_PERF_EVENT_ARRAY) {
> + pr_warning("map '%s' should be BPF_MAP_TYPE_PERF_EVENT_ARRAY\n",
> + bpf_map__name(map));
> + return ERR_PTR(-EINVAL);
> + }
> + if (bpf_map__fd(map) < 0) {
> + pr_warning("map '%s' doesn't have associated FD\n",
> + bpf_map__name(map));
> + return ERR_PTR(-EINVAL);
> + }
> + if (page_cnt & (page_cnt - 1)) {
> + pr_warning("page count should be power of two, but is %zu\n",
> + page_cnt);
> + return ERR_PTR(-EINVAL);
> + }
> +
> + pb = calloc(1, sizeof(*pb));
> + if (!pb)
> + return ERR_PTR(-ENOMEM);
> +
> + pb->sample_cb = sample_cb;
> + pb->lost_cb = lost_cb;
I think we need to check sample_cb != NULL && lost_cb != NULL.
> + pb->ctx = ctx;
> + pb->page_size = getpagesize();
> + pb->mmap_size = pb->page_size * page_cnt;
> + pb->mapfd = bpf_map__fd(map);
> +
> + pb->epfd = epoll_create1(EPOLL_CLOEXEC);
[...]
> +perf_buffer__process_record(struct perf_event_header *e, void *ctx)
> +{
> + struct perf_buffer *pb = ctx;
> + void *data = e;
> +
> + switch (e->type) {
> + case PERF_RECORD_SAMPLE: {
> + struct perf_sample_raw *s = data;
> +
> + pb->sample_cb(pb->ctx, s->data, s->size);
> + break;
> + }
> + case PERF_RECORD_LOST: {
> + struct perf_sample_lost *s = data;
> +
> + if (pb->lost_cb)
> + pb->lost_cb(pb->ctx, s->lost);
OK, we test lost_cb here, so not necessary at init time.
[...]
> bpf_program__attach_perf_event;
> bpf_program__attach_raw_tracepoint;
> bpf_program__attach_tracepoint;
> bpf_program__attach_uprobe;
> + btf__parse_elf;
Why move btf__parse_elf ?
Thanks,
Song
^ permalink raw reply
* Re: [PATCH bpf-next 2/2] selftests/bpf: test perf buffer API
From: Song Liu @ 2019-06-26 2:21 UTC (permalink / raw)
To: Andrii Nakryiko
Cc: Andrii Nakryiko, Alexei Starovoitov, Daniel Borkmann, bpf,
Networking, Kernel Team
In-Reply-To: <20190625232601.3227055-3-andriin@fb.com>
On Tue, Jun 25, 2019 at 4:27 PM Andrii Nakryiko <andriin@fb.com> wrote:
>
> Add test verifying perf buffer API functionality.
>
> Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
> ---
> .../selftests/bpf/prog_tests/perf_buffer.c | 86 +++++++++++++++++++
> .../selftests/bpf/progs/test_perf_buffer.c | 31 +++++++
> 2 files changed, 117 insertions(+)
> create mode 100644 tools/testing/selftests/bpf/prog_tests/perf_buffer.c
> create mode 100644 tools/testing/selftests/bpf/progs/test_perf_buffer.c
>
> diff --git a/tools/testing/selftests/bpf/prog_tests/perf_buffer.c b/tools/testing/selftests/bpf/prog_tests/perf_buffer.c
> new file mode 100644
> index 000000000000..3ba3e26141ac
> --- /dev/null
> +++ b/tools/testing/selftests/bpf/prog_tests/perf_buffer.c
> @@ -0,0 +1,86 @@
> +// SPDX-License-Identifier: GPL-2.0
> +#define _GNU_SOURCE
> +#include <pthread.h>
> +#include <sched.h>
> +#include <sys/socket.h>
> +#include <test_progs.h>
> +
> +static void on_sample(void *ctx, void *data, __u32 size)
> +{
> + cpu_set_t *cpu_seen = ctx;
> + int cpu = *(int *)data;
> +
> + CPU_SET(cpu, cpu_seen);
> +}
> +
> +void test_perf_buffer(void)
> +{
> + int err, prog_fd, prog_pfd, nr_cpus, i, duration = 0;
> + const char *prog_name = "kprobe/sys_nanosleep";
> + const char *file = "./test_perf_buffer.o";
> + struct bpf_map *perf_buf_map;
> + cpu_set_t cpu_set, cpu_seen;
> + struct bpf_program *prog;
> + struct bpf_object *obj;
> + struct perf_buffer *pb;
> +
> + nr_cpus = libbpf_num_possible_cpus();
> + if (CHECK(nr_cpus < 0, "nr_cpus", "err %d\n", nr_cpus))
> + return;
> +
> + /* load program */
> + err = bpf_prog_load(file, BPF_PROG_TYPE_KPROBE, &obj, &prog_fd);
> + if (CHECK(err, "obj_load", "err %d errno %d\n", err, errno))
> + return;
> +
> + prog = bpf_object__find_program_by_title(obj, prog_name);
> + if (CHECK(!prog, "find_probe", "prog '%s' not found\n", prog_name))
> + goto out_close;
> +
> + /* load map */
> + perf_buf_map = bpf_object__find_map_by_name(obj, "perf_buf_map");
> + if (CHECK(!perf_buf_map, "find_perf_buf_map", "not found\n"))
> + goto out_close;
> +
> + /* attach kprobe */
> + prog_pfd = bpf_program__attach_kprobe(prog, false /* retprobe */,
> + "sys_nanosleep");
> + if (CHECK(prog_pfd < 0, "attach_kprobe", "err %d\n", prog_pfd))
> + goto out_close;
> +
> + /* set up perf buffer */
> + pb = perf_buffer__new(perf_buf_map, 1, on_sample, NULL, &cpu_seen);
> + if (CHECK(IS_ERR(pb), "perf_buf__new", "err %ld\n", PTR_ERR(pb)))
> + goto out_detach;
> +
> + /* trigger kprobe on every CPU */
> + CPU_ZERO(&cpu_seen);
> + for (i = 0; i < nr_cpus; i++) {
> + CPU_ZERO(&cpu_set);
> + CPU_SET(i, &cpu_set);
> +
> + err = pthread_setaffinity_np(pthread_self(), sizeof(cpu_set),
> + &cpu_set);
> + if (err && CHECK(err, "set_affinity", "cpu #%d, err %d\n",
> + i, err))
> + goto out_detach;
> +
> + usleep(1);
> + }
> +
> + /* read perf buffer */
> + err = perf_buffer__poll(pb, 100);
> + if (CHECK(err < 0, "perf_buffer__poll", "err %d\n", err))
> + goto out_free_pb;
> +
> + if (CHECK(CPU_COUNT(&cpu_seen) != nr_cpus, "seen_cpu_cnt",
> + "expect %d, seen %d\n", nr_cpus, CPU_COUNT(&cpu_seen)))
> + goto out_free_pb;
> +
> +out_free_pb:
> + perf_buffer__free(pb);
> +out_detach:
> + libbpf_perf_event_disable_and_close(prog_pfd);
> +out_close:
> + bpf_object__close(obj);
> +}
> diff --git a/tools/testing/selftests/bpf/progs/test_perf_buffer.c b/tools/testing/selftests/bpf/progs/test_perf_buffer.c
> new file mode 100644
> index 000000000000..ba961f608fd5
> --- /dev/null
> +++ b/tools/testing/selftests/bpf/progs/test_perf_buffer.c
> @@ -0,0 +1,31 @@
> +// SPDX-License-Identifier: GPL-2.0
> +// Copyright (c) 2019 Facebook
> +
> +#include <linux/ptrace.h>
> +#include <linux/bpf.h>
> +#include "bpf_helpers.h"
> +
> +struct {
> + int type;
> + int key_size;
> + int value_size;
> + int max_entries;
> +} perf_buf_map SEC(".maps") = {
> + .type = BPF_MAP_TYPE_PERF_EVENT_ARRAY,
> + .key_size = sizeof(int),
> + .value_size = sizeof(int),
> + .max_entries = 56,
> +};
> +
> +SEC("kprobe/sys_nanosleep")
> +int handle_sys_nanosleep_entry(struct pt_regs *ctx)
> +{
> + int cpu = bpf_get_smp_processor_id();
> +
> + bpf_perf_event_output(ctx, &perf_buf_map, BPF_F_CURRENT_CPU,
> + &cpu, sizeof(cpu));
> + return 0;
> +}
> +
> +char _license[] SEC("license") = "GPL";
> +__u32 _version SEC("version") = 1;
> --
> 2.17.1
>
^ permalink raw reply
* Re: [PATCH iproute2 1/2] devlink: fix format string warning for 32bit targets
From: Baruch Siach @ 2019-06-26 3:30 UTC (permalink / raw)
To: Stephen Hemminger; +Cc: Jiri Pirko, netdev, Aya Levin, Moshe Shemesh
In-Reply-To: <20190625115806.01e29659@hermes.lan>
Hi Stephen,
On Tue, Jun 25, 2019 at 11:58:06AM -0700, Stephen Hemminger wrote:
> On Tue, 25 Jun 2019 14:49:04 +0300
> Baruch Siach <baruch@tkos.co.il> wrote:
>
> > diff --git a/devlink/devlink.c b/devlink/devlink.c
> > index 436935f88bda..b400fab17578 100644
> > --- a/devlink/devlink.c
> > +++ b/devlink/devlink.c
> > @@ -1726,9 +1726,9 @@ static void pr_out_u64(struct dl *dl, const char *name, uint64_t val)
> > jsonw_u64_field(dl->jw, name, val);
> > } else {
> > if (g_indent_newline)
> > - pr_out("%s %lu", name, val);
> > + pr_out("%s %llu", name, val);
> > else
> > - pr_out(" %s %lu", name, val);
> > + pr_out(" %s %llu", name, val);
>
> But on 64 bit target %llu expects unsigned long long which is 128bit.
Is that a problem?
> The better way to fix this is to use:
> #include <inttypes.h>
>
> And the use the macro PRIu64
> pr_out(" %s %"PRIu64, name, val);
I think it makes the code harder to read. But OK, I'll post an update to this
patch and the next.
Thanks,
baruch
--
http://baruch.siach.name/blog/ ~. .~ Tk Open Systems
=}------------------------------------------------ooO--U--Ooo------------{=
- baruch@tkos.co.il - tel: +972.2.679.5364, http://www.tkos.co.il -
^ permalink raw reply
* Re: [PATCH net-next 2/2] net: sched: protect against stack overflow in TC act_mirred
From: Eyal Birger @ 2019-06-26 4:37 UTC (permalink / raw)
To: Jamal Hadi Salim, John Hurley
Cc: Linux Netdev List, David Miller, Florian Westphal, Simon Horman,
Jakub Kicinski, oss-drivers, shmulik
In-Reply-To: <4a4f2f81-d87a-2a45-36b9-ac101d937219@mojatatu.com>
Hi Jamal, John,
On Tue, 25 Jun 2019 07:24:37 -0400
Jamal Hadi Salim <jhs@mojatatu.com> wrote:
> On 2019-06-25 5:06 a.m., John Hurley wrote:
> > On Tue, Jun 25, 2019 at 9:30 AM Eyal Birger <eyal.birger@gmail.com>
> > wrote:
>
> > I'm not sure on the history of why a value of 4 was selected here
> > but it seems to fall into line with my findings.
>
> Back then we could only loop in one direction (as opposed to two right
> now) - so seeing something twice would have been suspect enough,
> so 4 seems to be a good number. I still think 4 is a good number.
I think the introduction of mirred ingress affects the 'seeing something
twice is suspicious' paradigm - see below.
> > Is there a hard requirement for >4 recursive calls here?
>
> I think this is where testcases help (which then get permanently
> added in tdc repository). Eyal - if you have a test scenario where
> this could be demonstrated it would help.
I don't have a _hard_ requirement for >4 recursive calls.
I did encounter use cases for 2 layers of stacked net devices using TC
mirred ingress. For example, first layer redirects traffic based on
incoming protocol - e.g. some tunneling criterion - and the second
layer redirects traffic based on the IP packet src/dst, something like:
+-----------+ +-----------+ +-----------+ +-----------+
| ip0 | | ip1 | | ip2 | | ip3 |
+-----------+ +-----------+ +-----------+ +-----------+
\ / \ /
\ / \ /
+-----------+ +-----------+
| proto0 | | proto1 |
+-----------+ +-----------+
\ /
\ /
+-----------+
| eth0 |
+-----------+
Where packets stem from eth0 and are redirected to the appropriate devices
using mirred ingress redirect with different criteria.
This is useful for example when each 'ip' device is part of a different
routing domain.
There are probably many other ways to do this kind of thing, but using mirred
ingress to demux the traffic provides freedom in the demux criteria while
having the benefit of a netdevice at each node allowing to use tcpdump and
other such facilities.
As such, I was concerned that a hard limit of 4 may be restrictive.
I too think Florian's suggestion of using netif_rx() in order to break
the recursion when limit is met (or always use it?) is a good approach
to try in order not to force restrictions while keeping the stack sane.
Eyal.
^ permalink raw reply
* Re: kernel panic: stack is corrupted in validate_chain
From: syzbot @ 2019-06-26 4:41 UTC (permalink / raw)
To: ast, daniel, john.fastabend, linux-kernel, netdev, syzkaller-bugs
In-Reply-To: <000000000000c7a272058c2cde21@google.com>
syzbot has bisected this bug to:
commit e9db4ef6bf4ca9894bb324c76e01b8f1a16b2650
Author: John Fastabend <john.fastabend@gmail.com>
Date: Sat Jun 30 13:17:47 2018 +0000
bpf: sockhash fix omitted bucket lock in sock_close
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=11d4e129a00000
start commit: 249155c2 Merge branch 'parisc-5.2-4' of git://git.kernel.o..
git tree: upstream
final crash: https://syzkaller.appspot.com/x/report.txt?x=13d4e129a00000
console output: https://syzkaller.appspot.com/x/log.txt?x=15d4e129a00000
kernel config: https://syzkaller.appspot.com/x/.config?x=9a31528e58cc12e2
dashboard link: https://syzkaller.appspot.com/bug?extid=6ba34346b252f2d497c7
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=135e34eea00000
Reported-by: syzbot+6ba34346b252f2d497c7@syzkaller.appspotmail.com
Fixes: e9db4ef6bf4c ("bpf: sockhash fix omitted bucket lock in sock_close")
For information about bisection process see: https://goo.gl/tpsmEJ#bisection
^ permalink raw reply
* Re: [PATCH bpf-next 1/2] libbpf: add perf buffer reading API
From: Andrii Nakryiko @ 2019-06-26 4:44 UTC (permalink / raw)
To: Song Liu
Cc: Andrii Nakryiko, Alexei Starovoitov, Daniel Borkmann, bpf,
Networking, Kernel Team
In-Reply-To: <CAPhsuW6FeBHHNgT3OA6x6i9kVsKutnVR46DFdkeG0cggaKbTnQ@mail.gmail.com>
On Tue, Jun 25, 2019 at 7:19 PM Song Liu <liu.song.a23@gmail.com> wrote:
>
> On Tue, Jun 25, 2019 at 4:28 PM Andrii Nakryiko <andriin@fb.com> wrote:
> >
> > BPF_MAP_TYPE_PERF_EVENT_ARRAY map is often used to send data from BPF program
> > to user space for additional processing. libbpf already has very low-level API
> > to read single CPU perf buffer, bpf_perf_event_read_simple(), but it's hard to
> > use and requires a lot of code to set everything up. This patch adds
> > perf_buffer abstraction on top of it, abstracting setting up and polling
> > per-CPU logic into simple and convenient API, similar to what BCC provides.
> >
> > perf_buffer__new() sets up per-CPU ring buffers and updates corresponding BPF
> > map entries. It accepts two user-provided callbacks: one for handling raw
> > samples and one for get notifications of lost samples due to buffer overflow.
> >
> > perf_buffer__poll() is used to fetch ring buffer data across all CPUs,
> > utilizing epoll instance.
> >
> > perf_buffer__free() does corresponding clean up and unsets FDs from BPF map.
> >
> > All APIs are not thread-safe. User should ensure proper locking/coordination if
> > used in multi-threaded set up.
> >
> > Signed-off-by: Andrii Nakryiko <andriin@fb.com>
>
> Overall looks good. Some nit below.
Thanks for review!
>
> > ---
> > tools/lib/bpf/libbpf.c | 282 +++++++++++++++++++++++++++++++++++++++
> > tools/lib/bpf/libbpf.h | 12 ++
> > tools/lib/bpf/libbpf.map | 5 +-
> > 3 files changed, 298 insertions(+), 1 deletion(-)
>
> [...]
>
> > +struct perf_buffer *perf_buffer__new(struct bpf_map *map, size_t page_cnt,
> > + perf_buffer_sample_fn sample_cb,
> > + perf_buffer_lost_fn lost_cb, void *ctx)
> > +{
> > + char msg[STRERR_BUFSIZE];
> > + struct perf_buffer *pb;
> > + int err, cpu;
> > +
> > + if (bpf_map__def(map)->type != BPF_MAP_TYPE_PERF_EVENT_ARRAY) {
> > + pr_warning("map '%s' should be BPF_MAP_TYPE_PERF_EVENT_ARRAY\n",
> > + bpf_map__name(map));
> > + return ERR_PTR(-EINVAL);
> > + }
> > + if (bpf_map__fd(map) < 0) {
> > + pr_warning("map '%s' doesn't have associated FD\n",
> > + bpf_map__name(map));
> > + return ERR_PTR(-EINVAL);
> > + }
> > + if (page_cnt & (page_cnt - 1)) {
> > + pr_warning("page count should be power of two, but is %zu\n",
> > + page_cnt);
> > + return ERR_PTR(-EINVAL);
> > + }
> > +
> > + pb = calloc(1, sizeof(*pb));
> > + if (!pb)
> > + return ERR_PTR(-ENOMEM);
> > +
> > + pb->sample_cb = sample_cb;
> > + pb->lost_cb = lost_cb;
>
> I think we need to check sample_cb != NULL && lost_cb != NULL.
I was thinking about making them all either optional or required, but
eventually decided on making sample_cb required and lost_cb optional,
as in practice rarely sample_cb wouldn't be provided, while not every
application would care about handling lost samples (as there is little
you can do about that, except for bumping some counter).
As for checking for NULL. I feel like that's overkill. If someone
provided NULL for sample_cb, they will get SIGSEGV with stack trace
immediately showing that's it's sample_cb being NULL. Unlike Java, C
libraries tend not to double-check every pointer for NULL. Checking
for things like whether map has FD or is of correct type is valuable,
because if you don't check it early, then you'll just eventually get
-EINVAL from kernel and will start a guessing game of what's wrong.
Checking for callback to be non-null feels unnecessary, as it will be
immediately obvious (and it's quite unlikely this will happen in
practice).
>
> > + pb->ctx = ctx;
> > + pb->page_size = getpagesize();
> > + pb->mmap_size = pb->page_size * page_cnt;
> > + pb->mapfd = bpf_map__fd(map);
> > +
> > + pb->epfd = epoll_create1(EPOLL_CLOEXEC);
> [...]
> > +perf_buffer__process_record(struct perf_event_header *e, void *ctx)
> > +{
> > + struct perf_buffer *pb = ctx;
> > + void *data = e;
> > +
> > + switch (e->type) {
> > + case PERF_RECORD_SAMPLE: {
> > + struct perf_sample_raw *s = data;
> > +
> > + pb->sample_cb(pb->ctx, s->data, s->size);
> > + break;
> > + }
> > + case PERF_RECORD_LOST: {
> > + struct perf_sample_lost *s = data;
> > +
> > + if (pb->lost_cb)
> > + pb->lost_cb(pb->ctx, s->lost);
>
> OK, we test lost_cb here, so not necessary at init time.
>
> [...]
> > bpf_program__attach_perf_event;
> > bpf_program__attach_raw_tracepoint;
> > bpf_program__attach_tracepoint;
> > bpf_program__attach_uprobe;
> > + btf__parse_elf;
>
> Why move btf__parse_elf ?
I realized that I haven't put it in correct alphabetical order,
decided to fix it here, as it's just a single line change.
>
> Thanks,
> Song
^ permalink raw reply
* Re: [PATCH net] net: make skb_dst_force return false when dst was cleared
From: Eric Dumazet @ 2019-06-26 4:50 UTC (permalink / raw)
To: Florian Westphal, Eric Dumazet; +Cc: netdev
In-Reply-To: <20190625195943.44jvck5syvnzxb55@breakpoint.cc>
On 6/25/19 12:59 PM, Florian Westphal wrote:
> Eric Dumazet <eric.dumazet@gmail.com> wrote:
>>> -static inline void skb_dst_force(struct sk_buff *skb)
>>> +static inline bool skb_dst_force(struct sk_buff *skb)
>>> {
>>> if (skb_dst_is_noref(skb)) {
>>> struct dst_entry *dst = skb_dst(skb);
>>> @@ -313,7 +314,10 @@ static inline void skb_dst_force(struct sk_buff *skb)
>>> dst = NULL;
>>>
>>> skb->_skb_refdst = (unsigned long)dst;
>>> + return dst != NULL;
>>> }
>>> +
>>> + return true;
>>
>> This will return true, even if skb has a NULL dst.
>
> Yes, that was intentional -- it should return false to
> let caller know that no reference could be obtained and
> that the dst was invalidated as a result.
Problem is that some callers ignore skb_dst_force() return value.
>
>> Say if we have two skb_dst_force() calls for some reason
>> on the same skb, only the first one will return false.
>
> What would you suggest instead?
>
> Alternative is something like
>
> if (skb_dst(skb)) {
> skb_dst_force(skb);
> if (!skb_dst(skb)) {
> kfree_skb(skb);
> goto err;
> }
> }
Simply change
return true;
by
return skb->_skb_refdst != 0UL;
^ permalink raw reply
* Re: [PATCH bpf-next] libbpf: fix max() type mismatch for 32bit
From: Andrii Nakryiko @ 2019-06-26 4:58 UTC (permalink / raw)
To: Ivan Khoronzhuk
Cc: Alexei Starovoitov, Networking, Daniel Borkmann, bpf, open list
In-Reply-To: <20190625202700.28030-1-ivan.khoronzhuk@linaro.org>
On Tue, Jun 25, 2019 at 1:28 PM Ivan Khoronzhuk
<ivan.khoronzhuk@linaro.org> wrote:
>
> It fixes build error for 32bit caused by type mismatch
> size_t/unsigned long.
>
> Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
> ---
Sorry, forgot to mention, this should probably have
Fixes: bf82927125dd ("libbpf: refactor map initialization")
With that:
Acked-by: Andrii Nakryiko <andriin@fb.com>
> tools/lib/bpf/libbpf.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
> index 68f45a96769f..5186b7710430 100644
> --- a/tools/lib/bpf/libbpf.c
> +++ b/tools/lib/bpf/libbpf.c
> @@ -778,7 +778,7 @@ static struct bpf_map *bpf_object__add_map(struct bpf_object *obj)
> if (obj->nr_maps < obj->maps_cap)
> return &obj->maps[obj->nr_maps++];
>
> - new_cap = max(4ul, obj->maps_cap * 3 / 2);
> + new_cap = max((size_t)4, obj->maps_cap * 3 / 2);
> new_maps = realloc(obj->maps, new_cap * sizeof(*obj->maps));
> if (!new_maps) {
> pr_warning("alloc maps for object failed\n");
> --
> 2.17.1
>
^ permalink raw reply
* Re: [PATCH net] vxlan: do not destroy fdb if register_netdevice() is failed
From: Roopa Prabhu @ 2019-06-26 5:03 UTC (permalink / raw)
To: Taehee Yoo; +Cc: David Miller, Netdev
In-Reply-To: <CAMArcTWG-KLsmzrtQRGGmnUN31yz4UMqJ9FLyv3xNNPoXY_6=Q@mail.gmail.com>
On Tue, Jun 25, 2019 at 9:08 AM Taehee Yoo <ap420073@gmail.com> wrote:
>
> On Tue, 25 Jun 2019 at 13:12, Roopa Prabhu <roopa@cumulusnetworks.com> wrote:
> >
>
> Hi Roopa,
>
> Thank you for the review!
>
> > On Sun, Jun 23, 2019 at 7:18 PM Taehee Yoo <ap420073@gmail.com> wrote:
> > >
> > > On Mon, 24 Jun 2019 at 03:07, David Miller <davem@davemloft.net> wrote:
> > > >
> > >
> > > Hi David,
> > >
> > > Thank you for the review!
> > >
> > > > From: Taehee Yoo <ap420073@gmail.com>
> > > > Date: Thu, 20 Jun 2019 20:51:08 +0900
> > > >
> > > > > __vxlan_dev_create() destroys FDB using specific pointer which indicates
> > > > > a fdb when error occurs.
> > > > > But that pointer should not be used when register_netdevice() fails because
> > > > > register_netdevice() internally destroys fdb when error occurs.
> > > > >
> > > > > In order to avoid un-registered dev's notification, fdb destroying routine
> > > > > checks dev's register status before notification.
> > > >
> > > > Simply pass do_notify as false in this failure code path of __vxlan_dev_create(),
> > > > thank you.
> > >
> > > Failure path of __vxlan_dev_create() can't handle do_notify in that case
> > > because if register_netdevice() fails it internally calls
> > > ->ndo_uninit() which is
> > > vxlan_uninit().
> > > vxlan_uninit() internally calls vxlan_fdb_delete_default() and it callls
> > > vxlan_fdb_destroy().
> > > do_notify of vxlan_fdb_destroy() in vxlan_fdb_delete_default() is always true.
> > > So, failure path of __vxlan_dev_create() doesn't have any opportunity to
> > > handle do_notify.
> >
> >
> > I don't see register_netdevice calling ndo_uninit in case of all
> > errors. In the case where it does not,
> > does your patch leak the fdb entry ?.
> >
> > Wondering if we should just use vxlan_fdb_delete_default with a notify
> > flag to delete the entry if exists.
> > Will that help ?
> >
> > There is another commit that touched this code path:
> > commit 6db9246871394b3a136cd52001a0763676563840
> >
> > Author: Petr Machata <petrm@mellanox.com>
> > Date: Tue Dec 18 13:16:00 2018 +0000
> > vxlan: Fix error path in __vxlan_dev_create()
>
> I have checked up failure path of register_netdevice().
> Yes, this patch leaks fdb entry.
> There are 3 failure cases in the register_netdevice().
> A. error occurs before calling ->ndo_init().
> it doesn't call ->ndo_uninit().
> B. error occurs after calling ->ndo_init().
> it calls ->ndo_uninit() and dev->reg_state is NETREG_UNINITIALIZED.
> C. error occurs after registering netdev. it calls rollback_registered().
> rollback_registered() internally calls ->ndo_uninit()
> and dev->reg_state is NETREG_UNREGISTERING.
>
> A panic due to these problem could be fixed by using
> vxlan_fdb_delete_default() with notify flag.
> But notification problem could not be fixed clearly
> because of the case C.
yes, you are right. The notification issue still remains.
>
> I don't have clear solution for the case C.
> Please let me know, if you have any good idea for fixing the case C.
One option is a variant of fdb create. alloc the fdb but don't assign
it to the vxlan dev.
__vxlan_dev_create
create fdb entry
register_netdevice
rtnl_configure_link
link fdb to vxlan
fdb notify
Yet another option is moving fdb create after register_netdevice
__vxlan_dev_create
register_netdevice
rtnl_configure_link
create fdb entry
fdb notify
But if fdb create fails, user-space will see , NEWLINK + DELLINK when
creating a vxlan device and that seems weird.
^ permalink raw reply
* Re: [PATCH bpf-next 2/2] selftests/bpf: test perf buffer API
From: Andrii Nakryiko @ 2019-06-26 5:11 UTC (permalink / raw)
To: Andrii Nakryiko
Cc: Alexei Starovoitov, Daniel Borkmann, bpf, Networking, Kernel Team
In-Reply-To: <20190625232601.3227055-3-andriin@fb.com>
On Tue, Jun 25, 2019 at 4:26 PM Andrii Nakryiko <andriin@fb.com> wrote:
>
> Add test verifying perf buffer API functionality.
>
> Signed-off-by: Andrii Nakryiko <andriin@fb.com>
> ---
> .../selftests/bpf/prog_tests/perf_buffer.c | 86 +++++++++++++++++++
> .../selftests/bpf/progs/test_perf_buffer.c | 31 +++++++
> 2 files changed, 117 insertions(+)
> create mode 100644 tools/testing/selftests/bpf/prog_tests/perf_buffer.c
> create mode 100644 tools/testing/selftests/bpf/progs/test_perf_buffer.c
>
> diff --git a/tools/testing/selftests/bpf/prog_tests/perf_buffer.c b/tools/testing/selftests/bpf/prog_tests/perf_buffer.c
> new file mode 100644
> index 000000000000..3ba3e26141ac
> --- /dev/null
> +++ b/tools/testing/selftests/bpf/prog_tests/perf_buffer.c
> @@ -0,0 +1,86 @@
> +// SPDX-License-Identifier: GPL-2.0
> +#define _GNU_SOURCE
> +#include <pthread.h>
> +#include <sched.h>
> +#include <sys/socket.h>
> +#include <test_progs.h>
> +
> +static void on_sample(void *ctx, void *data, __u32 size)
> +{
> + cpu_set_t *cpu_seen = ctx;
> + int cpu = *(int *)data;
> +
> + CPU_SET(cpu, cpu_seen);
> +}
> +
> +void test_perf_buffer(void)
> +{
> + int err, prog_fd, prog_pfd, nr_cpus, i, duration = 0;
> + const char *prog_name = "kprobe/sys_nanosleep";
> + const char *file = "./test_perf_buffer.o";
> + struct bpf_map *perf_buf_map;
> + cpu_set_t cpu_set, cpu_seen;
> + struct bpf_program *prog;
> + struct bpf_object *obj;
> + struct perf_buffer *pb;
> +
> + nr_cpus = libbpf_num_possible_cpus();
> + if (CHECK(nr_cpus < 0, "nr_cpus", "err %d\n", nr_cpus))
> + return;
> +
> + /* load program */
> + err = bpf_prog_load(file, BPF_PROG_TYPE_KPROBE, &obj, &prog_fd);
> + if (CHECK(err, "obj_load", "err %d errno %d\n", err, errno))
> + return;
> +
> + prog = bpf_object__find_program_by_title(obj, prog_name);
> + if (CHECK(!prog, "find_probe", "prog '%s' not found\n", prog_name))
> + goto out_close;
> +
> + /* load map */
> + perf_buf_map = bpf_object__find_map_by_name(obj, "perf_buf_map");
> + if (CHECK(!perf_buf_map, "find_perf_buf_map", "not found\n"))
> + goto out_close;
> +
> + /* attach kprobe */
> + prog_pfd = bpf_program__attach_kprobe(prog, false /* retprobe */,
> + "sys_nanosleep");
> + if (CHECK(prog_pfd < 0, "attach_kprobe", "err %d\n", prog_pfd))
> + goto out_close;
> +
> + /* set up perf buffer */
> + pb = perf_buffer__new(perf_buf_map, 1, on_sample, NULL, &cpu_seen);
> + if (CHECK(IS_ERR(pb), "perf_buf__new", "err %ld\n", PTR_ERR(pb)))
> + goto out_detach;
> +
> + /* trigger kprobe on every CPU */
> + CPU_ZERO(&cpu_seen);
> + for (i = 0; i < nr_cpus; i++) {
> + CPU_ZERO(&cpu_set);
> + CPU_SET(i, &cpu_set);
> +
> + err = pthread_setaffinity_np(pthread_self(), sizeof(cpu_set),
> + &cpu_set);
> + if (err && CHECK(err, "set_affinity", "cpu #%d, err %d\n",
> + i, err))
> + goto out_detach;
> +
> + usleep(1);
> + }
> +
> + /* read perf buffer */
> + err = perf_buffer__poll(pb, 100);
> + if (CHECK(err < 0, "perf_buffer__poll", "err %d\n", err))
> + goto out_free_pb;
> +
> + if (CHECK(CPU_COUNT(&cpu_seen) != nr_cpus, "seen_cpu_cnt",
> + "expect %d, seen %d\n", nr_cpus, CPU_COUNT(&cpu_seen)))
> + goto out_free_pb;
> +
> +out_free_pb:
> + perf_buffer__free(pb);
> +out_detach:
> + libbpf_perf_event_disable_and_close(prog_pfd);
> +out_close:
> + bpf_object__close(obj);
> +}
> diff --git a/tools/testing/selftests/bpf/progs/test_perf_buffer.c b/tools/testing/selftests/bpf/progs/test_perf_buffer.c
> new file mode 100644
> index 000000000000..ba961f608fd5
> --- /dev/null
> +++ b/tools/testing/selftests/bpf/progs/test_perf_buffer.c
> @@ -0,0 +1,31 @@
> +// SPDX-License-Identifier: GPL-2.0
> +// Copyright (c) 2019 Facebook
> +
> +#include <linux/ptrace.h>
> +#include <linux/bpf.h>
> +#include "bpf_helpers.h"
> +
> +struct {
> + int type;
> + int key_size;
> + int value_size;
> + int max_entries;
> +} perf_buf_map SEC(".maps") = {
> + .type = BPF_MAP_TYPE_PERF_EVENT_ARRAY,
> + .key_size = sizeof(int),
> + .value_size = sizeof(int),
> + .max_entries = 56,
Oh, this is not right, "works for me" only :). I've been meaning to
actually have another change to handle not specified max_entries (or
equivalently, max_entries == 0) to mean "all possible CPUs" for
BPF_MAP_TYPE_PERF_EVENT_ARRAY. Will produce v2 with that change.
> +};
> +
> +SEC("kprobe/sys_nanosleep")
> +int handle_sys_nanosleep_entry(struct pt_regs *ctx)
> +{
> + int cpu = bpf_get_smp_processor_id();
> +
> + bpf_perf_event_output(ctx, &perf_buf_map, BPF_F_CURRENT_CPU,
> + &cpu, sizeof(cpu));
> + return 0;
> +}
> +
> +char _license[] SEC("license") = "GPL";
> +__u32 _version SEC("version") = 1;
> --
> 2.17.1
>
^ permalink raw reply
* Re: samples/bpf compilation failures - 5.2.0
From: Srinivas Ramana @ 2019-06-26 5:41 UTC (permalink / raw)
To: Alexei Starovoitov, Joel Fernandes, Daniel Borkmann,
Martin KaFai Lau, Song Liu, Yonghong Song, netdev, bpf
In-Reply-To: <faaf8b1c-9552-a0ae-3088-2f4255dff857@codeaurora.org>
+ Joel if he has seen this issue.
On 5/28/2019 2:27 PM, Srinivas Ramana wrote:
> Hello,
>
> I am trying to build samples/bpf in kernel(5.2.0-rc1) but unsuccessful
> with below errors. Can you help to point what i am missing or if there
> is some known issue?
>
> ==============================8<===================================
> $ make samples/bpf/
> LLC=/local/mnt/workspace/tools/clang_ubuntu/clang/clang+llvm-8.0.0-x86_64-linux-gnu-ubuntu-14.04/bin/llc
> CLANG=/local/mnt/workspace/tools/clang_ubuntu/clang/clang+llvm-8.0.0-x86_64-linux-gnu-ubuntu-14.04/bin/clang
> V=1
> make -C /local/mnt/workspace/sramana/kdev_torvalds/kdev/kernel -f
> /local/mnt/workspace/sramana/kdev_torvalds/kdev/kernel/Makefile
> samples/bpf/
> ................
> ................
> ................
> make KBUILD_MODULES=1 -f ./scripts/Makefile.build obj=samples/bpf
> (cat /dev/null; ) > samples/bpf/modules.order
> make -C
> /local/mnt/workspace/sramana/kdev_torvalds/kdev/kernel/samples/bpf/../../tools/lib/bpf/
> RM='rm -rf' LDFLAGS=
> srctree=/local/mnt/workspace/sramana/kdev_torvalds/kdev/kernel/samples/bpf/../../
> O=
>
> Auto-detecting system features:
> ... libelf: [ on ]
> ... bpf: [ on ]
>
> make -C
> /local/mnt/workspace/sramana/kdev_torvalds/kdev/kernel/samples/bpf/../..//tools/build
> CFLAGS= LDFLAGS= fixdep
> make -f
> /local/mnt/workspace/sramana/kdev_torvalds/kdev/kernel/samples/bpf/../..//tools/build/Makefile.build
> dir=. obj=fixdep
> ld -r -o fixdep-in.o fixdep.o
> ld: fixdep.o: Relocations in generic ELF (EM: 183)
> ld: fixdep.o: Relocations in generic ELF (EM: 183)
> fixdep.o: error adding symbols: File in wrong format
> make[5]: *** [fixdep-in.o] Error 1
> make[4]: *** [fixdep-in.o] Error 2
> make[3]: *** [fixdep] Error 2
> make[2]: ***
> [/local/mnt/workspace/sramana/kdev_torvalds/kdev/kernel/samples/bpf/../../tools/lib/bpf/libbpf.a]
> Error 2
> make[1]: *** [samples/bpf/] Error 2
> make: *** [sub-make] Error 2
> ==============================>8=======================================
>
>
> I am using the below commands to build:
> ========================================================
> export ARCH=arm64
> export CROSS_COMPILE=<path>linaro-toolchain/5.1/bin/aarch64-linux-gnu-
> export CLANG_TRIPLE=arm64-linux-gnu-
>
> make
> CC=<path>/clang_ubuntu/clang/clang+llvm-8.0.0-x86_64-linux-gnu-ubuntu-14.04/bin/clang
> defconfig
>
> make
> CC=<path>/clang_ubuntu/clang/clang+llvm-8.0.0-x86_64-linux-gnu-ubuntu-14.04/bin/clang
> -j8
>
> make
> CC=<path>/clang_ubuntu/clang/clang+llvm-8.0.0-x86_64-linux-gnu-ubuntu-14.04/bin/clang
> headers_install INSTALL_HDR_PATH=./usr
>
> make samples/bpf/
> LLC=<path>/clang_ubuntu/clang/clang+llvm-8.0.0-x86_64-linux-gnu-ubuntu-14.04/bin/llc
> CLANG=<path>/clang_ubuntu/clang/clang+llvm-8.0.0-x86_64-linux-gnu-ubuntu-14.04/bin/clang
> V=1
> CC=<path>/clang_ubuntu/clang/clang+llvm-8.0.0-x86_64-linux-gnu-ubuntu-14.04/bin/clang
>
> ========================================================
>
> Thanks,
> -- Srinivas R
>
--
Qualcomm India Private Limited, on behalf of Qualcomm Innovation
Center, Inc., is a member of Code Aurora Forum, a Linux Foundation
Collaborative Project
^ permalink raw reply
* [PATCH v2 bpf-next 0/3] libbpf: add perf buffer abstraction and API
From: Andrii Nakryiko @ 2019-06-26 6:12 UTC (permalink / raw)
To: andrii.nakryiko, ast, daniel, bpf, netdev, kernel-team; +Cc: Andrii Nakryiko
This patchset adds a high-level API for setting up and polling perf buffers
associated with BPF_MAP_TYPE_PERF_EVENT_ARRAY map. Details of APIs are
described in corresponding commit.
Patch #1 adds a set of APIs to set up and work with perf buffer.
Patch #2 enhances libbpf to supprot auto-setting PERF_EVENT_ARRAY map size.
Patch #3 adds test.
Andrii Nakryiko (3):
libbpf: add perf buffer API
libbpf: auto-set PERF_EVENT_ARRAY size to number of CPUs
selftests/bpf: test perf buffer API
tools/lib/bpf/libbpf.c | 299 +++++++++++++++++-
tools/lib/bpf/libbpf.h | 12 +
tools/lib/bpf/libbpf.map | 5 +-
.../selftests/bpf/prog_tests/perf_buffer.c | 86 +++++
.../selftests/bpf/progs/test_perf_buffer.c | 29 ++
5 files changed, 429 insertions(+), 2 deletions(-)
create mode 100644 tools/testing/selftests/bpf/prog_tests/perf_buffer.c
create mode 100644 tools/testing/selftests/bpf/progs/test_perf_buffer.c
--
2.17.1
^ permalink raw reply
* [PATCH v2 bpf-next 1/3] libbpf: add perf buffer API
From: Andrii Nakryiko @ 2019-06-26 6:12 UTC (permalink / raw)
To: andrii.nakryiko, ast, daniel, bpf, netdev, kernel-team; +Cc: Andrii Nakryiko
In-Reply-To: <20190626061235.602633-1-andriin@fb.com>
BPF_MAP_TYPE_PERF_EVENT_ARRAY map is often used to send data from BPF program
to user space for additional processing. libbpf already has very low-level API
to read single CPU perf buffer, bpf_perf_event_read_simple(), but it's hard to
use and requires a lot of code to set everything up. This patch adds
perf_buffer abstraction on top of it, abstracting setting up and polling
per-CPU logic into simple and convenient API, similar to what BCC provides.
perf_buffer__new() sets up per-CPU ring buffers and updates corresponding BPF
map entries. It accepts two user-provided callbacks: one for handling raw
samples and one for get notifications of lost samples due to buffer overflow.
perf_buffer__poll() is used to fetch ring buffer data across all CPUs,
utilizing epoll instance.
perf_buffer__free() does corresponding clean up and unsets FDs from BPF map.
All APIs are not thread-safe. User should ensure proper locking/coordination if
used in multi-threaded set up.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
---
tools/lib/bpf/libbpf.c | 282 +++++++++++++++++++++++++++++++++++++++
tools/lib/bpf/libbpf.h | 12 ++
tools/lib/bpf/libbpf.map | 5 +-
3 files changed, 298 insertions(+), 1 deletion(-)
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 9a4199b51300..c74cc535902a 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -32,7 +32,9 @@
#include <linux/limits.h>
#include <linux/perf_event.h>
#include <linux/ring_buffer.h>
+#include <sys/epoll.h>
#include <sys/ioctl.h>
+#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/vfs.h>
@@ -4322,6 +4324,286 @@ bpf_perf_event_read_simple(void *mmap_mem, size_t mmap_size, size_t page_size,
return ret;
}
+struct perf_cpu_buf {
+ int fd;
+ void *base; /* mmap()'ed memory */
+ void *buf; /* for reconstructing segmented data */
+ size_t buf_size;
+};
+
+struct perf_buffer {
+ perf_buffer_sample_fn sample_cb;
+ perf_buffer_lost_fn lost_cb;
+ void *ctx; /* passed into callbacks */
+
+ size_t page_size;
+ size_t mmap_size;
+ struct perf_cpu_buf **cpu_bufs;
+ struct epoll_event *events;
+ int cpu_cnt;
+ int epfd; /* perf event FD */
+ int mapfd; /* BPF_MAP_TYPE_PERF_EVENT_ARRAY BPF map FD */
+};
+
+static void perf_buffer__free_cpu_buf(struct perf_buffer *pb,
+ struct perf_cpu_buf *cpu_buf, int cpu)
+{
+ if (!cpu_buf)
+ return;
+ if (cpu_buf->base &&
+ munmap(cpu_buf->base, pb->mmap_size + pb->page_size))
+ pr_warning("failed to munmap cpu_buf #%d\n", cpu);
+ if (cpu_buf->fd >= 0) {
+ ioctl(cpu_buf->fd, PERF_EVENT_IOC_DISABLE, 0);
+ close(cpu_buf->fd);
+ }
+ free(cpu_buf->buf);
+ free(cpu_buf);
+}
+
+void perf_buffer__free(struct perf_buffer *pb)
+{
+ int i;
+
+ if (!pb)
+ return;
+ if (pb->cpu_bufs) {
+ for (i = 0; i < pb->cpu_cnt && pb->cpu_bufs[i]; i++) {
+ struct perf_cpu_buf *cpu_buf = pb->cpu_bufs[i];
+
+ bpf_map_delete_elem(pb->mapfd, &i);
+ perf_buffer__free_cpu_buf(pb, cpu_buf, i);
+ }
+ free(pb->cpu_bufs);
+ }
+ if (pb->epfd >= 0)
+ close(pb->epfd);
+ free(pb->events);
+ free(pb);
+}
+
+static struct perf_cpu_buf *perf_buffer__open_cpu_buf(struct perf_buffer *pb,
+ int cpu)
+{
+ struct perf_event_attr attr = {};
+ struct perf_cpu_buf *cpu_buf;
+ char msg[STRERR_BUFSIZE];
+ int err;
+
+ cpu_buf = calloc(1, sizeof(*cpu_buf));
+ if (!cpu_buf)
+ return ERR_PTR(-ENOMEM);
+
+ 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;
+ cpu_buf->fd = syscall(__NR_perf_event_open, &attr, -1 /* pid */, cpu,
+ -1, PERF_FLAG_FD_CLOEXEC);
+ if (cpu_buf->fd < 0) {
+ err = -errno;
+ pr_warning("failed to open perf buffer event on cpu #%d: %s\n",
+ cpu, libbpf_strerror_r(err, msg, sizeof(msg)));
+ goto error;
+ }
+
+ cpu_buf->base = mmap(NULL, pb->mmap_size + pb->page_size,
+ PROT_READ | PROT_WRITE, MAP_SHARED,
+ cpu_buf->fd, 0);
+ if (cpu_buf->base == MAP_FAILED) {
+ cpu_buf->base = NULL;
+ err = -errno;
+ pr_warning("failed to mmap perf buffer on cpu #%d: %s\n",
+ cpu, libbpf_strerror_r(err, msg, sizeof(msg)));
+ goto error;
+ }
+
+ if (ioctl(cpu_buf->fd, PERF_EVENT_IOC_ENABLE, 0) < 0) {
+ err = -errno;
+ pr_warning("failed to enable perf buffer event on cpu #%d: %s\n",
+ cpu, libbpf_strerror_r(err, msg, sizeof(msg)));
+ goto error;
+ }
+
+ return cpu_buf;
+
+error:
+ perf_buffer__free_cpu_buf(pb, cpu_buf, cpu);
+ return (struct perf_cpu_buf *)ERR_PTR(err);
+}
+
+struct perf_buffer *perf_buffer__new(struct bpf_map *map, size_t page_cnt,
+ perf_buffer_sample_fn sample_cb,
+ perf_buffer_lost_fn lost_cb, void *ctx)
+{
+ char msg[STRERR_BUFSIZE];
+ struct perf_buffer *pb;
+ int err, cpu;
+
+ if (bpf_map__def(map)->type != BPF_MAP_TYPE_PERF_EVENT_ARRAY) {
+ pr_warning("map '%s' should be BPF_MAP_TYPE_PERF_EVENT_ARRAY\n",
+ bpf_map__name(map));
+ return ERR_PTR(-EINVAL);
+ }
+ if (bpf_map__fd(map) < 0) {
+ pr_warning("map '%s' doesn't have associated FD\n",
+ bpf_map__name(map));
+ return ERR_PTR(-EINVAL);
+ }
+ if (page_cnt & (page_cnt - 1)) {
+ pr_warning("page count should be power of two, but is %zu\n",
+ page_cnt);
+ return ERR_PTR(-EINVAL);
+ }
+
+ pb = calloc(1, sizeof(*pb));
+ if (!pb)
+ return ERR_PTR(-ENOMEM);
+
+ pb->sample_cb = sample_cb;
+ pb->lost_cb = lost_cb;
+ pb->ctx = ctx;
+ pb->page_size = getpagesize();
+ pb->mmap_size = pb->page_size * page_cnt;
+ pb->mapfd = bpf_map__fd(map);
+
+ pb->epfd = epoll_create1(EPOLL_CLOEXEC);
+ if (pb->epfd < 0) {
+ err = -errno;
+ pr_warning("failed to create epoll instance: %s\n",
+ libbpf_strerror_r(err, msg, sizeof(msg)));
+ goto error;
+ }
+
+ pb->cpu_cnt = libbpf_num_possible_cpus();
+ if (pb->cpu_cnt < 0) {
+ err = pb->cpu_cnt;
+ goto error;
+ }
+ pb->events = calloc(pb->cpu_cnt, sizeof(*pb->events));
+ if (!pb->events) {
+ err = -ENOMEM;
+ pr_warning("failed to allocate events: out of memory\n");
+ goto error;
+ }
+ pb->cpu_bufs = calloc(pb->cpu_cnt, sizeof(*pb->cpu_bufs));
+ if (!pb->cpu_bufs) {
+ err = -ENOMEM;
+ pr_warning("failed to allocate buffers: out of memory\n");
+ goto error;
+ }
+
+ for (cpu = 0; cpu < pb->cpu_cnt; cpu++) {
+ struct perf_cpu_buf *cpu_buf;
+
+ cpu_buf = perf_buffer__open_cpu_buf(pb, cpu);
+ if (IS_ERR(cpu_buf)) {
+ err = PTR_ERR(cpu_buf);
+ goto error;
+ }
+
+ pb->cpu_bufs[cpu] = cpu_buf;
+
+ err = bpf_map_update_elem(pb->mapfd, &cpu, &cpu_buf->fd, 0);
+ if (err) {
+ pr_warning("failed to set cpu #%d perf FD %d: %s\n",
+ cpu, cpu_buf->fd,
+ libbpf_strerror_r(err, msg, sizeof(msg)));
+ goto error;
+ }
+
+ pb->events[cpu].events = EPOLLIN;
+ pb->events[cpu].data.ptr = cpu_buf;
+ if (epoll_ctl(pb->epfd, EPOLL_CTL_ADD, cpu_buf->fd,
+ &pb->events[cpu]) < 0) {
+ err = -errno;
+ pr_warning("failed to epoll_ctl cpu #%d perf FD %d: %s\n",
+ cpu, cpu_buf->fd,
+ libbpf_strerror_r(err, msg, sizeof(msg)));
+ goto error;
+ }
+ }
+
+ return pb;
+
+error:
+ if (pb)
+ perf_buffer__free(pb);
+ return ERR_PTR(err);
+}
+
+struct perf_sample_raw {
+ struct perf_event_header header;
+ uint32_t size;
+ char data[0];
+};
+
+struct perf_sample_lost {
+ struct perf_event_header header;
+ uint64_t id;
+ uint64_t lost;
+ uint64_t sample_id;
+};
+
+static enum bpf_perf_event_ret
+perf_buffer__process_record(struct perf_event_header *e, void *ctx)
+{
+ struct perf_buffer *pb = ctx;
+ void *data = e;
+
+ switch (e->type) {
+ case PERF_RECORD_SAMPLE: {
+ struct perf_sample_raw *s = data;
+
+ pb->sample_cb(pb->ctx, s->data, s->size);
+ break;
+ }
+ case PERF_RECORD_LOST: {
+ struct perf_sample_lost *s = data;
+
+ if (pb->lost_cb)
+ pb->lost_cb(pb->ctx, s->lost);
+ break;
+ }
+ default:
+ pr_warning("unknown perf sample type %d\n", e->type);
+ return LIBBPF_PERF_EVENT_ERROR;
+ }
+ return LIBBPF_PERF_EVENT_CONT;
+}
+
+static int perf_buffer__process_records(struct perf_buffer *pb,
+ struct perf_cpu_buf *cpu_buf)
+{
+ enum bpf_perf_event_ret ret;
+
+ ret = bpf_perf_event_read_simple(cpu_buf->base, pb->mmap_size,
+ pb->page_size, &cpu_buf->buf,
+ &cpu_buf->buf_size,
+ perf_buffer__process_record, pb);
+ if (ret != LIBBPF_PERF_EVENT_CONT)
+ return ret;
+ return 0;
+}
+
+int perf_buffer__poll(struct perf_buffer *pb, int timeout_ms)
+{
+ int cnt, err;
+
+ cnt = epoll_wait(pb->epfd, pb->events, pb->cpu_cnt, timeout_ms);
+ for (int i = 0; i < cnt; i++) {
+ struct perf_cpu_buf *cpu_buf = pb->events[i].data.ptr;
+
+ err = perf_buffer__process_records(pb, cpu_buf);
+ if (err) {
+ pr_warning("error while processing records: %d\n", err);
+ return err;
+ }
+ }
+ return cnt < 0 ? -errno : cnt;
+}
+
struct bpf_prog_info_array_desc {
int array_offset; /* e.g. offset of jited_prog_insns */
int count_offset; /* e.g. offset of jited_prog_len */
diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
index bf7020a565c6..3bfde1a475ce 100644
--- a/tools/lib/bpf/libbpf.h
+++ b/tools/lib/bpf/libbpf.h
@@ -354,6 +354,18 @@ LIBBPF_API int bpf_prog_load(const char *file, enum bpf_prog_type type,
LIBBPF_API int bpf_set_link_xdp_fd(int ifindex, int fd, __u32 flags);
LIBBPF_API int bpf_get_link_xdp_id(int ifindex, __u32 *prog_id, __u32 flags);
+struct perf_buffer;
+typedef void (*perf_buffer_sample_fn)(void *ctx, void *data, __u32 size);
+typedef void (*perf_buffer_lost_fn)(void *ctx, __u64 cnt);
+
+LIBBPF_API struct perf_buffer *perf_buffer__new(struct bpf_map *map,
+ size_t page_cnt,
+ perf_buffer_sample_fn sample_cb,
+ perf_buffer_lost_fn lost_cb,
+ void *ctx);
+LIBBPF_API void perf_buffer__free(struct perf_buffer *pb);
+LIBBPF_API int perf_buffer__poll(struct perf_buffer *pb, int timeout_ms);
+
enum bpf_perf_event_ret {
LIBBPF_PERF_EVENT_DONE = 0,
LIBBPF_PERF_EVENT_ERROR = -1,
diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map
index 2382fbda4cbb..10f48103110a 100644
--- a/tools/lib/bpf/libbpf.map
+++ b/tools/lib/bpf/libbpf.map
@@ -170,13 +170,16 @@ LIBBPF_0.0.4 {
btf_dump__dump_type;
btf_dump__free;
btf_dump__new;
- btf__parse_elf;
bpf_object__load_xattr;
bpf_program__attach_kprobe;
bpf_program__attach_perf_event;
bpf_program__attach_raw_tracepoint;
bpf_program__attach_tracepoint;
bpf_program__attach_uprobe;
+ btf__parse_elf;
libbpf_num_possible_cpus;
libbpf_perf_event_disable_and_close;
+ perf_buffer__free;
+ perf_buffer__new;
+ perf_buffer__poll;
} LIBBPF_0.0.3;
--
2.17.1
^ permalink raw reply related
* [PATCH v2 bpf-next 2/3] libbpf: auto-set PERF_EVENT_ARRAY size to number of CPUs
From: Andrii Nakryiko @ 2019-06-26 6:12 UTC (permalink / raw)
To: andrii.nakryiko, ast, daniel, bpf, netdev, kernel-team; +Cc: Andrii Nakryiko
In-Reply-To: <20190626061235.602633-1-andriin@fb.com>
For BPF_MAP_TYPE_PERF_EVENT_ARRAY typically correct size is number of
possible CPUs. This is impossible to specify at compilation time. This
change adds automatic setting of PERF_EVENT_ARRAY size to number of
system CPUs, unless non-zero size is specified explicitly. This allows
to adjust size for advanced specific cases, while providing convenient
and logical defaults.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
---
tools/lib/bpf/libbpf.c | 17 ++++++++++++++++-
1 file changed, 16 insertions(+), 1 deletion(-)
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index c74cc535902a..8f2b8a081ba7 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -2114,6 +2114,7 @@ static int
bpf_object__create_maps(struct bpf_object *obj)
{
struct bpf_create_map_attr create_attr = {};
+ int nr_cpus = 0;
unsigned int i;
int err;
@@ -2136,7 +2137,21 @@ bpf_object__create_maps(struct bpf_object *obj)
create_attr.map_flags = def->map_flags;
create_attr.key_size = def->key_size;
create_attr.value_size = def->value_size;
- create_attr.max_entries = def->max_entries;
+ if (def->type == BPF_MAP_TYPE_PERF_EVENT_ARRAY &&
+ !def->max_entries) {
+ if (!nr_cpus)
+ nr_cpus = libbpf_num_possible_cpus();
+ if (nr_cpus < 0) {
+ pr_warning("failed to determine number of system CPUs: %d\n",
+ nr_cpus);
+ return nr_cpus;
+ }
+ pr_debug("map '%s': setting size to %d\n",
+ map->name, nr_cpus);
+ create_attr.max_entries = nr_cpus;
+ } else {
+ create_attr.max_entries = def->max_entries;
+ }
create_attr.btf_fd = 0;
create_attr.btf_key_type_id = 0;
create_attr.btf_value_type_id = 0;
--
2.17.1
^ permalink raw reply related
* [PATCH v2 bpf-next 3/3] selftests/bpf: test perf buffer API
From: Andrii Nakryiko @ 2019-06-26 6:12 UTC (permalink / raw)
To: andrii.nakryiko, ast, daniel, bpf, netdev, kernel-team; +Cc: Andrii Nakryiko
In-Reply-To: <20190626061235.602633-1-andriin@fb.com>
Add test verifying perf buffer API functionality.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
---
.../selftests/bpf/prog_tests/perf_buffer.c | 86 +++++++++++++++++++
.../selftests/bpf/progs/test_perf_buffer.c | 29 +++++++
2 files changed, 115 insertions(+)
create mode 100644 tools/testing/selftests/bpf/prog_tests/perf_buffer.c
create mode 100644 tools/testing/selftests/bpf/progs/test_perf_buffer.c
diff --git a/tools/testing/selftests/bpf/prog_tests/perf_buffer.c b/tools/testing/selftests/bpf/prog_tests/perf_buffer.c
new file mode 100644
index 000000000000..3ba3e26141ac
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/perf_buffer.c
@@ -0,0 +1,86 @@
+// SPDX-License-Identifier: GPL-2.0
+#define _GNU_SOURCE
+#include <pthread.h>
+#include <sched.h>
+#include <sys/socket.h>
+#include <test_progs.h>
+
+static void on_sample(void *ctx, void *data, __u32 size)
+{
+ cpu_set_t *cpu_seen = ctx;
+ int cpu = *(int *)data;
+
+ CPU_SET(cpu, cpu_seen);
+}
+
+void test_perf_buffer(void)
+{
+ int err, prog_fd, prog_pfd, nr_cpus, i, duration = 0;
+ const char *prog_name = "kprobe/sys_nanosleep";
+ const char *file = "./test_perf_buffer.o";
+ struct bpf_map *perf_buf_map;
+ cpu_set_t cpu_set, cpu_seen;
+ struct bpf_program *prog;
+ struct bpf_object *obj;
+ struct perf_buffer *pb;
+
+ nr_cpus = libbpf_num_possible_cpus();
+ if (CHECK(nr_cpus < 0, "nr_cpus", "err %d\n", nr_cpus))
+ return;
+
+ /* load program */
+ err = bpf_prog_load(file, BPF_PROG_TYPE_KPROBE, &obj, &prog_fd);
+ if (CHECK(err, "obj_load", "err %d errno %d\n", err, errno))
+ return;
+
+ prog = bpf_object__find_program_by_title(obj, prog_name);
+ if (CHECK(!prog, "find_probe", "prog '%s' not found\n", prog_name))
+ goto out_close;
+
+ /* load map */
+ perf_buf_map = bpf_object__find_map_by_name(obj, "perf_buf_map");
+ if (CHECK(!perf_buf_map, "find_perf_buf_map", "not found\n"))
+ goto out_close;
+
+ /* attach kprobe */
+ prog_pfd = bpf_program__attach_kprobe(prog, false /* retprobe */,
+ "sys_nanosleep");
+ if (CHECK(prog_pfd < 0, "attach_kprobe", "err %d\n", prog_pfd))
+ goto out_close;
+
+ /* set up perf buffer */
+ pb = perf_buffer__new(perf_buf_map, 1, on_sample, NULL, &cpu_seen);
+ if (CHECK(IS_ERR(pb), "perf_buf__new", "err %ld\n", PTR_ERR(pb)))
+ goto out_detach;
+
+ /* trigger kprobe on every CPU */
+ CPU_ZERO(&cpu_seen);
+ for (i = 0; i < nr_cpus; i++) {
+ CPU_ZERO(&cpu_set);
+ CPU_SET(i, &cpu_set);
+
+ err = pthread_setaffinity_np(pthread_self(), sizeof(cpu_set),
+ &cpu_set);
+ if (err && CHECK(err, "set_affinity", "cpu #%d, err %d\n",
+ i, err))
+ goto out_detach;
+
+ usleep(1);
+ }
+
+ /* read perf buffer */
+ err = perf_buffer__poll(pb, 100);
+ if (CHECK(err < 0, "perf_buffer__poll", "err %d\n", err))
+ goto out_free_pb;
+
+ if (CHECK(CPU_COUNT(&cpu_seen) != nr_cpus, "seen_cpu_cnt",
+ "expect %d, seen %d\n", nr_cpus, CPU_COUNT(&cpu_seen)))
+ goto out_free_pb;
+
+out_free_pb:
+ perf_buffer__free(pb);
+out_detach:
+ libbpf_perf_event_disable_and_close(prog_pfd);
+out_close:
+ bpf_object__close(obj);
+}
diff --git a/tools/testing/selftests/bpf/progs/test_perf_buffer.c b/tools/testing/selftests/bpf/progs/test_perf_buffer.c
new file mode 100644
index 000000000000..8609f0031bc0
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/test_perf_buffer.c
@@ -0,0 +1,29 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2019 Facebook
+
+#include <linux/ptrace.h>
+#include <linux/bpf.h>
+#include "bpf_helpers.h"
+
+struct {
+ int type;
+ int key_size;
+ int value_size;
+} perf_buf_map SEC(".maps") = {
+ .type = BPF_MAP_TYPE_PERF_EVENT_ARRAY,
+ .key_size = sizeof(int),
+ .value_size = sizeof(int),
+};
+
+SEC("kprobe/sys_nanosleep")
+int handle_sys_nanosleep_entry(struct pt_regs *ctx)
+{
+ int cpu = bpf_get_smp_processor_id();
+
+ bpf_perf_event_output(ctx, &perf_buf_map, BPF_F_CURRENT_CPU,
+ &cpu, sizeof(cpu));
+ return 0;
+}
+
+char _license[] SEC("license") = "GPL";
+__u32 _version SEC("version") = 1;
--
2.17.1
^ permalink raw reply related
* [PATCH net v2] ipv4: reset rt_iif for recirculated mcast/bcast out pkts
From: Stephen Suryaputra @ 2019-06-26 6:21 UTC (permalink / raw)
To: netdev; +Cc: dsahern, Stephen Suryaputra
Multicast or broadcast egress packets have rt_iif set to the oif. These
packets might be recirculated back as input and lookup to the raw
sockets may fail because they are bound to the incoming interface
(skb_iif). If rt_iif is not zero, during the lookup, inet_iif() function
returns rt_iif instead of skb_iif. Hence, the lookup fails.
v2: Make it non vrf specific (David Ahern). Reword the changelog to
reflect it.
Signed-off-by: Stephen Suryaputra <ssuryaextr@gmail.com>
---
include/net/route.h | 1 +
net/ipv4/ip_output.c | 12 ++++++++++++
net/ipv4/route.c | 33 +++++++++++++++++++++++++++++++++
3 files changed, 46 insertions(+)
diff --git a/include/net/route.h b/include/net/route.h
index 065b47754f05..55ff71ffb796 100644
--- a/include/net/route.h
+++ b/include/net/route.h
@@ -221,6 +221,7 @@ void ip_rt_get_source(u8 *src, struct sk_buff *skb, struct rtable *rt);
struct rtable *rt_dst_alloc(struct net_device *dev,
unsigned int flags, u16 type,
bool nopolicy, bool noxfrm, bool will_cache);
+struct rtable *rt_dst_clone(struct net_device *dev, struct rtable *rt);
struct in_ifaddr;
void fib_add_ifaddr(struct in_ifaddr *);
diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index 16f9159234a2..8c2ec35b6512 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -318,6 +318,7 @@ static int ip_finish_output(struct net *net, struct sock *sk, struct sk_buff *sk
static int ip_mc_finish_output(struct net *net, struct sock *sk,
struct sk_buff *skb)
{
+ struct rtable *new_rt;
int ret;
ret = BPF_CGROUP_RUN_PROG_INET_EGRESS(sk, skb);
@@ -326,6 +327,17 @@ static int ip_mc_finish_output(struct net *net, struct sock *sk,
return ret;
}
+ /* Reset rt_iif so that inet_iif() will return skb->skb_iif. Setting
+ * this to non-zero causes ipi_ifindex in in_pktinfo to be overwritten,
+ * see ipv4_pktinfo_prepare().
+ */
+ new_rt = rt_dst_clone(net->loopback_dev, skb_rtable(skb));
+ if (new_rt) {
+ new_rt->rt_iif = 0;
+ skb_dst_drop(skb);
+ skb_dst_set(skb, &new_rt->dst);
+ }
+
return dev_loopback_xmit(net, sk, skb);
}
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 6cb7cff22db9..8ea0735a6754 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -1647,6 +1647,39 @@ struct rtable *rt_dst_alloc(struct net_device *dev,
}
EXPORT_SYMBOL(rt_dst_alloc);
+struct rtable *rt_dst_clone(struct net_device *dev, struct rtable *rt)
+{
+ struct rtable *new_rt;
+
+ new_rt = dst_alloc(&ipv4_dst_ops, dev, 1, DST_OBSOLETE_FORCE_CHK,
+ rt->dst.flags);
+
+ if (new_rt) {
+ new_rt->rt_genid = rt_genid_ipv4(dev_net(dev));
+ new_rt->rt_flags = rt->rt_flags;
+ new_rt->rt_type = rt->rt_type;
+ new_rt->rt_is_input = rt->rt_is_input;
+ new_rt->rt_iif = rt->rt_iif;
+ new_rt->rt_pmtu = rt->rt_pmtu;
+ new_rt->rt_mtu_locked = rt->rt_mtu_locked;
+ new_rt->rt_gw_family = rt->rt_gw_family;
+ if (rt->rt_gw_family == AF_INET)
+ new_rt->rt_gw4 = rt->rt_gw4;
+ else if (rt->rt_gw_family == AF_INET6)
+ new_rt->rt_gw6 = rt->rt_gw6;
+ INIT_LIST_HEAD(&new_rt->rt_uncached);
+
+ new_rt->dst.flags |= DST_HOST;
+ new_rt->dst.input = rt->dst.input;
+ new_rt->dst.output = rt->dst.output;
+ new_rt->dst.error = rt->dst.error;
+ new_rt->dst.lastuse = jiffies;
+ new_rt->dst.lwtstate = lwtstate_get(rt->dst.lwtstate);
+ }
+ return new_rt;
+}
+EXPORT_SYMBOL(rt_dst_clone);
+
/* called in rcu_read_lock() section */
int ip_mc_validate_source(struct sk_buff *skb, __be32 daddr, __be32 saddr,
u8 tos, struct net_device *dev,
--
2.17.1
^ permalink raw reply related
* Re: [PATCH] can: mcp251x: add error check when wq alloc failed
From: Sean Nyekjaer @ 2019-06-26 6:26 UTC (permalink / raw)
To: Willem de Bruijn, Weitao Hou
Cc: Wolfgang Grandegger, Marc Kleine-Budde, David Miller,
Greg Kroah-Hartman, allison, tglx, linux-can, Network Development,
linux-kernel
In-Reply-To: <CA+FuTSegsUvPSWX+CZuafSD32Sx+xJmYPiQ92geDNqAe8_JGrQ@mail.gmail.com>
On 25/06/2019 16.03, Willem de Bruijn wrote:
> On Tue, Jun 25, 2019 at 8:51 AM Weitao Hou <houweitaoo@gmail.com> wrote:
>>
>> add error check when workqueue alloc failed, and remove
>> redundant code to make it clear
>>
>> Signed-off-by: Weitao Hou <houweitaoo@gmail.com>
>
> Acked-by: Willem de Bruijn <willemb@google.com>
>
Tested-by: Sean Nyekjaer <sean@geanix.com>
^ permalink raw reply
page: next (older) | prev (newer) | latest
- recent:[subjects (threaded)|topics (new)|topics (active)]
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox