* [PATCH 01/16] tools: Adopt memdup() from tools/perf, moving it to tools/lib/string.c
2015-11-17 15:31 [GIT PULL 00/16] perf/ebpf improvements and fixes Arnaldo Carvalho de Melo
@ 2015-11-17 15:31 ` Arnaldo Carvalho de Melo
2015-11-17 15:31 ` [PATCH 02/16] tools: Clone the kernel's strtobool function Arnaldo Carvalho de Melo
` (15 subsequent siblings)
16 siblings, 0 replies; 21+ messages in thread
From: Arnaldo Carvalho de Melo @ 2015-11-17 15:31 UTC (permalink / raw)
To: Ingo Molnar
Cc: linux-kernel, Arnaldo Carvalho de Melo, Adrian Hunter,
Alexey Dobriyan, David Ahern, Jiri Olsa, Namhyung Kim
From: Arnaldo Carvalho de Melo <acme@redhat.com>
That will contain more string functions with counterparts, sometimes
verbatim copies, in the kernel.
Acked-by: Wang Nan <wangnan0@huawei.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/n/tip-rah6g97kn21vfgmlramorz6o@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/include/linux/string.h | 9 +++++++++
tools/lib/string.c | 19 +++++++++++++++++++
tools/perf/MANIFEST | 2 ++
tools/perf/util/Build | 6 ++++++
tools/perf/util/include/linux/string.h | 3 ---
tools/perf/util/string.c | 16 ----------------
6 files changed, 36 insertions(+), 19 deletions(-)
create mode 100644 tools/include/linux/string.h
create mode 100644 tools/lib/string.c
delete mode 100644 tools/perf/util/include/linux/string.h
diff --git a/tools/include/linux/string.h b/tools/include/linux/string.h
new file mode 100644
index 000000000000..f3a6db6ad732
--- /dev/null
+++ b/tools/include/linux/string.h
@@ -0,0 +1,9 @@
+#ifndef _TOOLS_LINUX_STRING_H_
+#define _TOOLS_LINUX_STRING_H_
+
+
+#include <linux/types.h> /* for size_t */
+
+void *memdup(const void *src, size_t len);
+
+#endif /* _LINUX_STRING_H_ */
diff --git a/tools/lib/string.c b/tools/lib/string.c
new file mode 100644
index 000000000000..ecfd43a9b24e
--- /dev/null
+++ b/tools/lib/string.c
@@ -0,0 +1,19 @@
+#include <stdlib.h>
+#include <string.h>
+#include <linux/string.h>
+
+/**
+ * memdup - duplicate region of memory
+ *
+ * @src: memory region to duplicate
+ * @len: memory region length
+ */
+void *memdup(const void *src, size_t len)
+{
+ void *p = malloc(len);
+
+ if (p)
+ memcpy(p, src, len);
+
+ return p;
+}
diff --git a/tools/perf/MANIFEST b/tools/perf/MANIFEST
index 39c38cb45b00..2562eac6451d 100644
--- a/tools/perf/MANIFEST
+++ b/tools/perf/MANIFEST
@@ -22,6 +22,7 @@ tools/lib/api
tools/lib/bpf
tools/lib/hweight.c
tools/lib/rbtree.c
+tools/lib/string.c
tools/lib/symbol/kallsyms.c
tools/lib/symbol/kallsyms.h
tools/lib/util/find_next_bit.c
@@ -50,6 +51,7 @@ tools/include/linux/log2.h
tools/include/linux/poison.h
tools/include/linux/rbtree.h
tools/include/linux/rbtree_augmented.h
+tools/include/linux/string.h
tools/include/linux/types.h
tools/include/linux/err.h
include/asm-generic/bitops/arch_hweight.h
diff --git a/tools/perf/util/Build b/tools/perf/util/Build
index 591b3fe3ed49..e2316900f96f 100644
--- a/tools/perf/util/Build
+++ b/tools/perf/util/Build
@@ -21,6 +21,7 @@ libperf-y += parse-events.o
libperf-y += perf_regs.o
libperf-y += path.o
libperf-y += rbtree.o
+libperf-y += libstring.o
libperf-y += bitmap.o
libperf-y += hweight.o
libperf-y += run-command.o
@@ -138,6 +139,7 @@ $(OUTPUT)util/pmu.o: $(OUTPUT)util/pmu-flex.c $(OUTPUT)util/pmu-bison.c
CFLAGS_find_next_bit.o += -Wno-unused-parameter -DETC_PERFCONFIG="BUILD_STR($(ETC_PERFCONFIG_SQ))"
CFLAGS_rbtree.o += -Wno-unused-parameter -DETC_PERFCONFIG="BUILD_STR($(ETC_PERFCONFIG_SQ))"
+CFLAGS_libstring.o += -Wno-unused-parameter -DETC_PERFCONFIG="BUILD_STR($(ETC_PERFCONFIG_SQ))"
CFLAGS_hweight.o += -Wno-unused-parameter -DETC_PERFCONFIG="BUILD_STR($(ETC_PERFCONFIG_SQ))"
CFLAGS_parse-events.o += -Wno-redundant-decls
@@ -153,6 +155,10 @@ $(OUTPUT)util/rbtree.o: ../lib/rbtree.c FORCE
$(call rule_mkdir)
$(call if_changed_dep,cc_o_c)
+$(OUTPUT)util/libstring.o: ../lib/string.c FORCE
+ $(call rule_mkdir)
+ $(call if_changed_dep,cc_o_c)
+
$(OUTPUT)util/hweight.o: ../lib/hweight.c FORCE
$(call rule_mkdir)
$(call if_changed_dep,cc_o_c)
diff --git a/tools/perf/util/include/linux/string.h b/tools/perf/util/include/linux/string.h
deleted file mode 100644
index 6f19c548ecc0..000000000000
--- a/tools/perf/util/include/linux/string.h
+++ /dev/null
@@ -1,3 +0,0 @@
-#include <string.h>
-
-void *memdup(const void *src, size_t len);
diff --git a/tools/perf/util/string.c b/tools/perf/util/string.c
index fc8781de62db..7f7e072be746 100644
--- a/tools/perf/util/string.c
+++ b/tools/perf/util/string.c
@@ -342,22 +342,6 @@ char *rtrim(char *s)
return s;
}
-/**
- * memdup - duplicate region of memory
- * @src: memory region to duplicate
- * @len: memory region length
- */
-void *memdup(const void *src, size_t len)
-{
- void *p;
-
- p = malloc(len);
- if (p)
- memcpy(p, src, len);
-
- return p;
-}
-
char *asprintf_expr_inout_ints(const char *var, bool in, size_t nints, int *ints)
{
/*
--
2.1.0
^ permalink raw reply related [flat|nested] 21+ messages in thread* [PATCH 02/16] tools: Clone the kernel's strtobool function
2015-11-17 15:31 [GIT PULL 00/16] perf/ebpf improvements and fixes Arnaldo Carvalho de Melo
2015-11-17 15:31 ` [PATCH 01/16] tools: Adopt memdup() from tools/perf, moving it to tools/lib/string.c Arnaldo Carvalho de Melo
@ 2015-11-17 15:31 ` Arnaldo Carvalho de Melo
2015-11-17 15:31 ` [PATCH 03/16] bpf tools: Load a program with different instances using preprocessor Arnaldo Carvalho de Melo
` (14 subsequent siblings)
16 siblings, 0 replies; 21+ messages in thread
From: Arnaldo Carvalho de Melo @ 2015-11-17 15:31 UTC (permalink / raw)
To: Ingo Molnar
Cc: linux-kernel, Wang Nan, Alexei Starovoitov, Jonathan Cameron,
Masami Hiramatsu, Zefan Li, pi3orama, Arnaldo Carvalho de Melo
From: Wang Nan <wangnan0@huawei.com>
Copying it to tools/lib/string.c, the counterpart to the kernel's
lib/string.c.
This is preparation for enhancing BPF program configuration, which will
allow config string like 'inlines=yes'.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Jonathan Cameron <jic23@cam.ac.uk>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1447675815-166222-6-git-send-email-wangnan0@huawei.com
[ Copied it to tools/lib/string.c instead, to make it usable by other tools/ ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/include/linux/string.h | 2 ++
tools/lib/string.c | 43 +++++++++++++++++++++++++++++++++++++++++++
2 files changed, 45 insertions(+)
diff --git a/tools/include/linux/string.h b/tools/include/linux/string.h
index f3a6db6ad732..2e2f736c039c 100644
--- a/tools/include/linux/string.h
+++ b/tools/include/linux/string.h
@@ -6,4 +6,6 @@
void *memdup(const void *src, size_t len);
+int strtobool(const char *s, bool *res);
+
#endif /* _LINUX_STRING_H_ */
diff --git a/tools/lib/string.c b/tools/lib/string.c
index ecfd43a9b24e..065e54f42d8f 100644
--- a/tools/lib/string.c
+++ b/tools/lib/string.c
@@ -1,5 +1,20 @@
+/*
+ * linux/tools/lib/string.c
+ *
+ * Copied from linux/lib/string.c, where it is:
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ *
+ * More specifically, the first copied function was strtobool, which
+ * was introduced by:
+ *
+ * d0f1fed29e6e ("Add a strtobool function matching semantics of existing in kernel equivalents")
+ * Author: Jonathan Cameron <jic23@cam.ac.uk>
+ */
+
#include <stdlib.h>
#include <string.h>
+#include <errno.h>
#include <linux/string.h>
/**
@@ -17,3 +32,31 @@ void *memdup(const void *src, size_t len)
return p;
}
+
+/**
+ * strtobool - convert common user inputs into boolean values
+ * @s: input string
+ * @res: result
+ *
+ * This routine returns 0 iff the first character is one of 'Yy1Nn0'.
+ * Otherwise it will return -EINVAL. Value pointed to by res is
+ * updated upon finding a match.
+ */
+int strtobool(const char *s, bool *res)
+{
+ switch (s[0]) {
+ case 'y':
+ case 'Y':
+ case '1':
+ *res = true;
+ break;
+ case 'n':
+ case 'N':
+ case '0':
+ *res = false;
+ break;
+ default:
+ return -EINVAL;
+ }
+ return 0;
+}
--
2.1.0
^ permalink raw reply related [flat|nested] 21+ messages in thread* [PATCH 03/16] bpf tools: Load a program with different instances using preprocessor
2015-11-17 15:31 [GIT PULL 00/16] perf/ebpf improvements and fixes Arnaldo Carvalho de Melo
2015-11-17 15:31 ` [PATCH 01/16] tools: Adopt memdup() from tools/perf, moving it to tools/lib/string.c Arnaldo Carvalho de Melo
2015-11-17 15:31 ` [PATCH 02/16] tools: Clone the kernel's strtobool function Arnaldo Carvalho de Melo
@ 2015-11-17 15:31 ` Arnaldo Carvalho de Melo
2015-11-17 15:31 ` [PATCH 04/16] perf bpf: Add BPF_PROLOGUE config options for further patches Arnaldo Carvalho de Melo
` (13 subsequent siblings)
16 siblings, 0 replies; 21+ messages in thread
From: Arnaldo Carvalho de Melo @ 2015-11-17 15:31 UTC (permalink / raw)
To: Ingo Molnar
Cc: linux-kernel, Wang Nan, He Kuang, Alexei Starovoitov,
Masami Hiramatsu, Zefan Li, pi3orama, Arnaldo Carvalho de Melo
From: Wang Nan <wangnan0@huawei.com>
This patch is a preparation for BPF prologue support which allows
generating a series of BPF bytecode for fetching kernel data before
calling program code. With the newly introduced multiple instances
support, perf is able to create different prologues for different kprobe
points.
Before this patch, a bpf_program can be loaded into kernel only once,
and get the only resulting fd. What this patch does is to allow creating
and loading different variants of one bpf_program, then fetching their
fds.
Here we describe the basic idea in this patch. The detailed description
of the newly introduced APIs can be found in comments in the patch body.
The key of this patch is the new mechanism in bpf_program__load().
Instead of loading BPF program into kernel directly, it calls a
'pre-processor' to generate program instances which would be finally
loaded into the kernel based on the original code. To enable the
generation of multiple instances, libbpf passes an index to the
pre-processor so it know which instance is being loaded.
Pre-processor should be called from libbpf's user (perf) using
bpf_program__set_prep(). The number of instances and the relationship
between indices and the target instance should be clear when calling
bpf_program__set_prep().
To retrieve a fd for a specific instance of a program,
bpf_program__nth_fd() is introduced. It returns the resulting fd
according to index.
Signed-off-by: He Kuang <hekuang@huawei.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: He Kuang <hekuang@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1447675815-166222-8-git-send-email-wangnan0@huawei.com
Signed-off-by: Wang Nan <wangnan0@huawei.com>
[ Enclosed multi-line if/else blocks with {}, (*func_ptr)() -> func_ptr() ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/lib/bpf/libbpf.c | 146 ++++++++++++++++++++++++++++++++++++++++++++++---
tools/lib/bpf/libbpf.h | 64 ++++++++++++++++++++++
2 files changed, 201 insertions(+), 9 deletions(-)
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index e176bad19bcb..e3f4c3379f14 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -152,7 +152,11 @@ struct bpf_program {
} *reloc_desc;
int nr_reloc;
- int fd;
+ struct {
+ int nr;
+ int *fds;
+ } instances;
+ bpf_program_prep_t preprocessor;
struct bpf_object *obj;
void *priv;
@@ -206,10 +210,25 @@ struct bpf_object {
static void bpf_program__unload(struct bpf_program *prog)
{
+ int i;
+
if (!prog)
return;
- zclose(prog->fd);
+ /*
+ * If the object is opened but the program was never loaded,
+ * it is possible that prog->instances.nr == -1.
+ */
+ if (prog->instances.nr > 0) {
+ for (i = 0; i < prog->instances.nr; i++)
+ zclose(prog->instances.fds[i]);
+ } else if (prog->instances.nr != -1) {
+ pr_warning("Internal error: instances.nr is %d\n",
+ prog->instances.nr);
+ }
+
+ prog->instances.nr = -1;
+ zfree(&prog->instances.fds);
}
static void bpf_program__exit(struct bpf_program *prog)
@@ -260,7 +279,8 @@ bpf_program__init(void *data, size_t size, char *name, int idx,
memcpy(prog->insns, data,
prog->insns_cnt * sizeof(struct bpf_insn));
prog->idx = idx;
- prog->fd = -1;
+ prog->instances.fds = NULL;
+ prog->instances.nr = -1;
return 0;
errout:
@@ -860,13 +880,73 @@ static int
bpf_program__load(struct bpf_program *prog,
char *license, u32 kern_version)
{
- int err, fd;
+ int err = 0, fd, i;
- err = load_program(prog->insns, prog->insns_cnt,
- license, kern_version, &fd);
- if (!err)
- prog->fd = fd;
+ if (prog->instances.nr < 0 || !prog->instances.fds) {
+ if (prog->preprocessor) {
+ pr_warning("Internal error: can't load program '%s'\n",
+ prog->section_name);
+ return -LIBBPF_ERRNO__INTERNAL;
+ }
+ prog->instances.fds = malloc(sizeof(int));
+ if (!prog->instances.fds) {
+ pr_warning("Not enough memory for BPF fds\n");
+ return -ENOMEM;
+ }
+ prog->instances.nr = 1;
+ prog->instances.fds[0] = -1;
+ }
+
+ if (!prog->preprocessor) {
+ if (prog->instances.nr != 1) {
+ pr_warning("Program '%s' is inconsistent: nr(%d) != 1\n",
+ prog->section_name, prog->instances.nr);
+ }
+ err = load_program(prog->insns, prog->insns_cnt,
+ license, kern_version, &fd);
+ if (!err)
+ prog->instances.fds[0] = fd;
+ goto out;
+ }
+
+ for (i = 0; i < prog->instances.nr; i++) {
+ struct bpf_prog_prep_result result;
+ bpf_program_prep_t preprocessor = prog->preprocessor;
+
+ bzero(&result, sizeof(result));
+ err = preprocessor(prog, i, prog->insns,
+ prog->insns_cnt, &result);
+ if (err) {
+ pr_warning("Preprocessing the %dth instance of program '%s' failed\n",
+ i, prog->section_name);
+ goto out;
+ }
+
+ if (!result.new_insn_ptr || !result.new_insn_cnt) {
+ pr_debug("Skip loading the %dth instance of program '%s'\n",
+ i, prog->section_name);
+ prog->instances.fds[i] = -1;
+ if (result.pfd)
+ *result.pfd = -1;
+ continue;
+ }
+
+ err = load_program(result.new_insn_ptr,
+ result.new_insn_cnt,
+ license, kern_version, &fd);
+
+ if (err) {
+ pr_warning("Loading the %dth instance of program '%s' failed\n",
+ i, prog->section_name);
+ goto out;
+ }
+
+ if (result.pfd)
+ *result.pfd = fd;
+ prog->instances.fds[i] = fd;
+ }
+out:
if (err)
pr_warning("failed to load program '%s'\n",
prog->section_name);
@@ -1121,5 +1201,53 @@ const char *bpf_program__title(struct bpf_program *prog, bool needs_copy)
int bpf_program__fd(struct bpf_program *prog)
{
- return prog->fd;
+ return bpf_program__nth_fd(prog, 0);
+}
+
+int bpf_program__set_prep(struct bpf_program *prog, int nr_instances,
+ bpf_program_prep_t prep)
+{
+ int *instances_fds;
+
+ if (nr_instances <= 0 || !prep)
+ return -EINVAL;
+
+ if (prog->instances.nr > 0 || prog->instances.fds) {
+ pr_warning("Can't set pre-processor after loading\n");
+ return -EINVAL;
+ }
+
+ instances_fds = malloc(sizeof(int) * nr_instances);
+ if (!instances_fds) {
+ pr_warning("alloc memory failed for fds\n");
+ return -ENOMEM;
+ }
+
+ /* fill all fd with -1 */
+ memset(instances_fds, -1, sizeof(int) * nr_instances);
+
+ prog->instances.nr = nr_instances;
+ prog->instances.fds = instances_fds;
+ prog->preprocessor = prep;
+ return 0;
+}
+
+int bpf_program__nth_fd(struct bpf_program *prog, int n)
+{
+ int fd;
+
+ if (n >= prog->instances.nr || n < 0) {
+ pr_warning("Can't get the %dth fd from program %s: only %d instances\n",
+ n, prog->section_name, prog->instances.nr);
+ return -EINVAL;
+ }
+
+ fd = prog->instances.fds[n];
+ if (fd < 0) {
+ pr_warning("%dth instance of program '%s' is invalid\n",
+ n, prog->section_name);
+ return -ENOENT;
+ }
+
+ return fd;
}
diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
index c9a9aef2806c..949df4b346cf 100644
--- a/tools/lib/bpf/libbpf.h
+++ b/tools/lib/bpf/libbpf.h
@@ -88,6 +88,70 @@ const char *bpf_program__title(struct bpf_program *prog, bool needs_copy);
int bpf_program__fd(struct bpf_program *prog);
+struct bpf_insn;
+
+/*
+ * Libbpf allows callers to adjust BPF programs before being loaded
+ * into kernel. One program in an object file can be transform into
+ * multiple variants to be attached to different code.
+ *
+ * bpf_program_prep_t, bpf_program__set_prep and bpf_program__nth_fd
+ * are APIs for this propose.
+ *
+ * - bpf_program_prep_t:
+ * It defines 'preprocessor', which is a caller defined function
+ * passed to libbpf through bpf_program__set_prep(), and will be
+ * called before program is loaded. The processor should adjust
+ * the program one time for each instances according to the number
+ * passed to it.
+ *
+ * - bpf_program__set_prep:
+ * Attachs a preprocessor to a BPF program. The number of instances
+ * whould be created is also passed through this function.
+ *
+ * - bpf_program__nth_fd:
+ * After the program is loaded, get resuling fds from bpf program for
+ * each instances.
+ *
+ * If bpf_program__set_prep() is not used, the program whould be loaded
+ * without adjustment during bpf_object__load(). The program has only
+ * one instance. In this case bpf_program__fd(prog) is equal to
+ * bpf_program__nth_fd(prog, 0).
+ */
+
+struct bpf_prog_prep_result {
+ /*
+ * If not NULL, load new instruction array.
+ * If set to NULL, don't load this instance.
+ */
+ struct bpf_insn *new_insn_ptr;
+ int new_insn_cnt;
+
+ /* If not NULL, result fd is set to it */
+ int *pfd;
+};
+
+/*
+ * Parameters of bpf_program_prep_t:
+ * - prog: The bpf_program being loaded.
+ * - n: Index of instance being generated.
+ * - insns: BPF instructions array.
+ * - insns_cnt:Number of instructions in insns.
+ * - res: Output parameter, result of transformation.
+ *
+ * Return value:
+ * - Zero: pre-processing success.
+ * - Non-zero: pre-processing, stop loading.
+ */
+typedef int (*bpf_program_prep_t)(struct bpf_program *prog, int n,
+ struct bpf_insn *insns, int insns_cnt,
+ struct bpf_prog_prep_result *res);
+
+int bpf_program__set_prep(struct bpf_program *prog, int nr_instance,
+ bpf_program_prep_t prep);
+
+int bpf_program__nth_fd(struct bpf_program *prog, int n);
+
/*
* We don't need __attribute__((packed)) now since it is
* unnecessary for 'bpf_map_def' because they are all aligned.
--
2.1.0
^ permalink raw reply related [flat|nested] 21+ messages in thread* [PATCH 04/16] perf bpf: Add BPF_PROLOGUE config options for further patches
2015-11-17 15:31 [GIT PULL 00/16] perf/ebpf improvements and fixes Arnaldo Carvalho de Melo
` (2 preceding siblings ...)
2015-11-17 15:31 ` [PATCH 03/16] bpf tools: Load a program with different instances using preprocessor Arnaldo Carvalho de Melo
@ 2015-11-17 15:31 ` Arnaldo Carvalho de Melo
2015-11-17 15:31 ` [PATCH 05/16] perf bpf: Compile dwarf-regs.c if CONFIG_BPF_PROLOGUE is on Arnaldo Carvalho de Melo
` (12 subsequent siblings)
16 siblings, 0 replies; 21+ messages in thread
From: Arnaldo Carvalho de Melo @ 2015-11-17 15:31 UTC (permalink / raw)
To: Ingo Molnar
Cc: linux-kernel, Wang Nan, Alexei Starovoitov, Masami Hiramatsu,
Zefan Li, pi3orama, Arnaldo Carvalho de Melo
From: Wang Nan <wangnan0@huawei.com>
If both LIBBPF and DWARF are detected, it is possible to create prologue
for eBPF programs to help them access kernel data. HAVE_BPF_PROLOGUE and
CONFIG_BPF_PROLOGUE are added as flags for this feature.
PERF_HAVE_ARCH_REGS_QUERY_REGISTER_OFFSET is introduced in commit
63ab024a5b6f295ca17a293ad81b7c728f49a89a ("perf tools:
regs_query_register_offset() infrastructure"), which indicates that an
architecture supports converting name of a register to its offset in
'struct pt_regs'. Without this support, BPF_PROLOGUE should be turned
off.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1447675815-166222-9-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/config/Makefile | 12 ++++++++++++
1 file changed, 12 insertions(+)
diff --git a/tools/perf/config/Makefile b/tools/perf/config/Makefile
index de89ec574361..6eb9a956a408 100644
--- a/tools/perf/config/Makefile
+++ b/tools/perf/config/Makefile
@@ -318,6 +318,18 @@ ifndef NO_LIBELF
CFLAGS += -DHAVE_LIBBPF_SUPPORT
$(call detected,CONFIG_LIBBPF)
endif
+
+ ifndef NO_DWARF
+ ifdef PERF_HAVE_ARCH_REGS_QUERY_REGISTER_OFFSET
+ CFLAGS += -DHAVE_BPF_PROLOGUE
+ $(call detected,CONFIG_BPF_PROLOGUE)
+ else
+ msg := $(warning BPF prologue is not supported by architecture $(ARCH), missing regs_query_register_offset());
+ endif
+ else
+ msg := $(warning DWARF support is off, BPF prologue is disabled);
+ endif
+
endif # NO_LIBBPF
endif # NO_LIBELF
--
2.1.0
^ permalink raw reply related [flat|nested] 21+ messages in thread* [PATCH 05/16] perf bpf: Compile dwarf-regs.c if CONFIG_BPF_PROLOGUE is on
2015-11-17 15:31 [GIT PULL 00/16] perf/ebpf improvements and fixes Arnaldo Carvalho de Melo
` (3 preceding siblings ...)
2015-11-17 15:31 ` [PATCH 04/16] perf bpf: Add BPF_PROLOGUE config options for further patches Arnaldo Carvalho de Melo
@ 2015-11-17 15:31 ` Arnaldo Carvalho de Melo
2015-11-17 15:31 ` [PATCH 06/16] perf bpf: Allow BPF program attach to uprobe events Arnaldo Carvalho de Melo
` (11 subsequent siblings)
16 siblings, 0 replies; 21+ messages in thread
From: Arnaldo Carvalho de Melo @ 2015-11-17 15:31 UTC (permalink / raw)
To: Ingo Molnar
Cc: linux-kernel, Wang Nan, He Kuang, Alexei Starovoitov, Zefan Li,
pi3orama, Arnaldo Carvalho de Melo
From: Wang Nan <wangnan0@huawei.com>
regs_query_register_offset() in dwarf-regs.c is required by BPF
prologue. This patch compiles it if CONFIG_BPF_PROLOGUE is on to avoid
build failure when CONFIG_BPF_PROLOGUE is on but CONFIG_DWARF is not
set.
Signed-off-by: He Kuang <hekuang@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: He Kuang <hekuang@huawei.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1447675815-166222-10-git-send-email-wangnan0@huawei.com
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/arch/x86/util/Build | 1 +
1 file changed, 1 insertion(+)
diff --git a/tools/perf/arch/x86/util/Build b/tools/perf/arch/x86/util/Build
index ff63649fa9ac..465970370f3e 100644
--- a/tools/perf/arch/x86/util/Build
+++ b/tools/perf/arch/x86/util/Build
@@ -5,6 +5,7 @@ libperf-y += kvm-stat.o
libperf-y += perf_regs.o
libperf-$(CONFIG_DWARF) += dwarf-regs.o
+libperf-$(CONFIG_BPF_PROLOGUE) += dwarf-regs.o
libperf-$(CONFIG_LIBUNWIND) += unwind-libunwind.o
libperf-$(CONFIG_LIBDW_DWARF_UNWIND) += unwind-libdw.o
--
2.1.0
^ permalink raw reply related [flat|nested] 21+ messages in thread* [PATCH 06/16] perf bpf: Allow BPF program attach to uprobe events
2015-11-17 15:31 [GIT PULL 00/16] perf/ebpf improvements and fixes Arnaldo Carvalho de Melo
` (4 preceding siblings ...)
2015-11-17 15:31 ` [PATCH 05/16] perf bpf: Compile dwarf-regs.c if CONFIG_BPF_PROLOGUE is on Arnaldo Carvalho de Melo
@ 2015-11-17 15:31 ` Arnaldo Carvalho de Melo
2015-11-17 15:31 ` [PATCH 07/16] perf bpf: Allow attaching BPF programs to modules symbols Arnaldo Carvalho de Melo
` (10 subsequent siblings)
16 siblings, 0 replies; 21+ messages in thread
From: Arnaldo Carvalho de Melo @ 2015-11-17 15:31 UTC (permalink / raw)
To: Ingo Molnar
Cc: linux-kernel, Wang Nan, Alexei Starovoitov, Masami Hiramatsu,
Zefan Li, pi3orama, Arnaldo Carvalho de Melo
From: Wang Nan <wangnan0@huawei.com>
This patch adds a new syntax to the BPF object section name to support
probing at uprobe event. Now we can use BPF program like this:
SEC(
"exec=/lib64/libc.so.6;"
"libcwrite=__write"
)
int libcwrite(void *ctx)
{
return 1;
}
Where, in section name of a program, before the main config string, we
can use 'key=value' style options. Now the only option key is "exec",
for uprobes.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1447675815-166222-4-git-send-email-wangnan0@huawei.com
[ Changed the separator from \n to ; ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/util/bpf-loader.c | 120 ++++++++++++++++++++++++++++++++++++++++---
tools/perf/util/bpf-loader.h | 1 +
2 files changed, 115 insertions(+), 6 deletions(-)
diff --git a/tools/perf/util/bpf-loader.c b/tools/perf/util/bpf-loader.c
index 4c50411371db..84169d6f2585 100644
--- a/tools/perf/util/bpf-loader.c
+++ b/tools/perf/util/bpf-loader.c
@@ -110,6 +110,113 @@ bpf_prog_priv__clear(struct bpf_program *prog __maybe_unused,
}
static int
+config__exec(const char *value, struct perf_probe_event *pev)
+{
+ pev->uprobes = true;
+ pev->target = strdup(value);
+ if (!pev->target)
+ return -ENOMEM;
+ return 0;
+}
+
+static struct {
+ const char *key;
+ const char *usage;
+ const char *desc;
+ int (*func)(const char *, struct perf_probe_event *);
+} bpf_config_terms[] = {
+ {
+ .key = "exec",
+ .usage = "exec=<full path of file>",
+ .desc = "Set uprobe target",
+ .func = config__exec,
+ },
+};
+
+static int
+do_config(const char *key, const char *value,
+ struct perf_probe_event *pev)
+{
+ unsigned int i;
+
+ pr_debug("config bpf program: %s=%s\n", key, value);
+ for (i = 0; i < ARRAY_SIZE(bpf_config_terms); i++)
+ if (strcmp(key, bpf_config_terms[i].key) == 0)
+ return bpf_config_terms[i].func(value, pev);
+
+ pr_debug("BPF: ERROR: invalid config option in object: %s=%s\n",
+ key, value);
+
+ pr_debug("\nHint: Currently valid options are:\n");
+ for (i = 0; i < ARRAY_SIZE(bpf_config_terms); i++)
+ pr_debug("\t%s:\t%s\n", bpf_config_terms[i].usage,
+ bpf_config_terms[i].desc);
+ pr_debug("\n");
+
+ return -BPF_LOADER_ERRNO__CONFIG_TERM;
+}
+
+static const char *
+parse_config_kvpair(const char *config_str, struct perf_probe_event *pev)
+{
+ char *text = strdup(config_str);
+ char *sep, *line;
+ const char *main_str = NULL;
+ int err = 0;
+
+ if (!text) {
+ pr_debug("No enough memory: dup config_str failed\n");
+ return ERR_PTR(-ENOMEM);
+ }
+
+ line = text;
+ while ((sep = strchr(line, ';'))) {
+ char *equ;
+
+ *sep = '\0';
+ equ = strchr(line, '=');
+ if (!equ) {
+ pr_warning("WARNING: invalid config in BPF object: %s\n",
+ line);
+ pr_warning("\tShould be 'key=value'.\n");
+ goto nextline;
+ }
+ *equ = '\0';
+
+ err = do_config(line, equ + 1, pev);
+ if (err)
+ break;
+nextline:
+ line = sep + 1;
+ }
+
+ if (!err)
+ main_str = config_str + (line - text);
+ free(text);
+
+ return err ? ERR_PTR(err) : main_str;
+}
+
+static int
+parse_config(const char *config_str, struct perf_probe_event *pev)
+{
+ int err;
+ const char *main_str = parse_config_kvpair(config_str, pev);
+
+ if (IS_ERR(main_str))
+ return PTR_ERR(main_str);
+
+ err = parse_perf_probe_command(main_str, pev);
+ if (err < 0) {
+ pr_debug("bpf: '%s' is not a valid config string\n",
+ config_str);
+ /* parse failed, don't need clear pev. */
+ return -BPF_LOADER_ERRNO__CONFIG;
+ }
+ return 0;
+}
+
+static int
config_bpf_program(struct bpf_program *prog)
{
struct perf_probe_event *pev = NULL;
@@ -131,13 +238,9 @@ config_bpf_program(struct bpf_program *prog)
pev = &priv->pev;
pr_debug("bpf: config program '%s'\n", config_str);
- err = parse_perf_probe_command(config_str, pev);
- if (err < 0) {
- pr_debug("bpf: '%s' is not a valid config string\n",
- config_str);
- err = -BPF_LOADER_ERRNO__CONFIG;
+ err = parse_config(config_str, pev);
+ if (err)
goto errout;
- }
if (pev->group && strcmp(pev->group, PERF_BPF_PROBE_GROUP)) {
pr_debug("bpf: '%s': group for event is set and not '%s'.\n",
@@ -340,6 +443,7 @@ static const char *bpf_loader_strerror_table[NR_ERRNO] = {
[ERRCODE_OFFSET(EVENTNAME)] = "No event name found in config string",
[ERRCODE_OFFSET(INTERNAL)] = "BPF loader internal error",
[ERRCODE_OFFSET(COMPILE)] = "Error when compiling BPF scriptlet",
+ [ERRCODE_OFFSET(CONFIG_TERM)] = "Invalid config term in config string",
};
static int
@@ -420,6 +524,10 @@ int bpf__strerror_probe(struct bpf_object *obj __maybe_unused,
int err, char *buf, size_t size)
{
bpf__strerror_head(err, buf, size);
+ case BPF_LOADER_ERRNO__CONFIG_TERM: {
+ scnprintf(buf, size, "%s (add -v to see detail)", emsg);
+ break;
+ }
bpf__strerror_entry(EEXIST, "Probe point exist. Try use 'perf probe -d \"*\"'");
bpf__strerror_entry(EACCES, "You need to be root");
bpf__strerror_entry(EPERM, "You need to be root, and /proc/sys/kernel/kptr_restrict should be 0");
diff --git a/tools/perf/util/bpf-loader.h b/tools/perf/util/bpf-loader.h
index 9caf3ae4acf3..d19f5c5d6d74 100644
--- a/tools/perf/util/bpf-loader.h
+++ b/tools/perf/util/bpf-loader.h
@@ -20,6 +20,7 @@ enum bpf_loader_errno {
BPF_LOADER_ERRNO__EVENTNAME, /* Event name is missing */
BPF_LOADER_ERRNO__INTERNAL, /* BPF loader internal error */
BPF_LOADER_ERRNO__COMPILE, /* Error when compiling BPF scriptlet */
+ BPF_LOADER_ERRNO__CONFIG_TERM, /* Invalid config term in config term */
__BPF_LOADER_ERRNO__END,
};
--
2.1.0
^ permalink raw reply related [flat|nested] 21+ messages in thread* [PATCH 07/16] perf bpf: Allow attaching BPF programs to modules symbols
2015-11-17 15:31 [GIT PULL 00/16] perf/ebpf improvements and fixes Arnaldo Carvalho de Melo
` (5 preceding siblings ...)
2015-11-17 15:31 ` [PATCH 06/16] perf bpf: Allow BPF program attach to uprobe events Arnaldo Carvalho de Melo
@ 2015-11-17 15:31 ` Arnaldo Carvalho de Melo
2015-11-17 15:31 ` [PATCH 08/16] perf bpf: Allow BPF program config probing options Arnaldo Carvalho de Melo
` (9 subsequent siblings)
16 siblings, 0 replies; 21+ messages in thread
From: Arnaldo Carvalho de Melo @ 2015-11-17 15:31 UTC (permalink / raw)
To: Ingo Molnar
Cc: linux-kernel, Wang Nan, Alexei Starovoitov, Brendan Gregg,
Daniel Borkmann, David Ahern, He Kuang, Jiri Olsa, Kaixu Xia,
Masami Hiramatsu, Namhyung Kim, Peter Zijlstra, Zefan Li,
pi3orama, Arnaldo Carvalho de Melo
From: Wang Nan <wangnan0@huawei.com>
By extending the syntax of BPF object section names, this patch allows
users to attach BPF programs to symbols in modules. For example:
SEC("module=i915;"
"parse_cmds=i915_parse_cmds")
int parse_cmds(void *ctx)
{
return 1;
}
The implementation is very simple: like what 'perf probe' does, for module,
fill 'uprobe' field in 'struct perf_probe_event'. Other parts will be done
automatically.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David Ahern <dsahern@gmail.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kaixu Xia <xiakaixu@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1447675815-166222-5-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/util/bpf-loader.c | 16 ++++++++++++++++
1 file changed, 16 insertions(+)
diff --git a/tools/perf/util/bpf-loader.c b/tools/perf/util/bpf-loader.c
index 84169d6f2585..d0f02ed93804 100644
--- a/tools/perf/util/bpf-loader.c
+++ b/tools/perf/util/bpf-loader.c
@@ -119,6 +119,16 @@ config__exec(const char *value, struct perf_probe_event *pev)
return 0;
}
+static int
+config__module(const char *value, struct perf_probe_event *pev)
+{
+ pev->uprobes = false;
+ pev->target = strdup(value);
+ if (!pev->target)
+ return -ENOMEM;
+ return 0;
+}
+
static struct {
const char *key;
const char *usage;
@@ -131,6 +141,12 @@ static struct {
.desc = "Set uprobe target",
.func = config__exec,
},
+ {
+ .key = "module",
+ .usage = "module=<module name> ",
+ .desc = "Set kprobe module",
+ .func = config__module,
+ }
};
static int
--
2.1.0
^ permalink raw reply related [flat|nested] 21+ messages in thread* [PATCH 08/16] perf bpf: Allow BPF program config probing options
2015-11-17 15:31 [GIT PULL 00/16] perf/ebpf improvements and fixes Arnaldo Carvalho de Melo
` (6 preceding siblings ...)
2015-11-17 15:31 ` [PATCH 07/16] perf bpf: Allow attaching BPF programs to modules symbols Arnaldo Carvalho de Melo
@ 2015-11-17 15:31 ` Arnaldo Carvalho de Melo
2015-11-17 15:31 ` [PATCH 09/16] perf bpf: Add prologue for BPF programs for fetching arguments Arnaldo Carvalho de Melo
` (8 subsequent siblings)
16 siblings, 0 replies; 21+ messages in thread
From: Arnaldo Carvalho de Melo @ 2015-11-17 15:31 UTC (permalink / raw)
To: Ingo Molnar
Cc: linux-kernel, Wang Nan, Alexei Starovoitov, Masami Hiramatsu,
Zefan Li, pi3orama, Arnaldo Carvalho de Melo
From: Wang Nan <wangnan0@huawei.com>
By extending the syntax of BPF object section names, this patch allows users to
config probing options like what they can do in 'perf probe'.
The error message in 'perf probe' is also updated.
Test result:
For following BPF file test_probe_glob.c:
# cat test_probe_glob.c
__attribute__((section("inlines=no;func=SyS_dup?"), used))
int func(void *ctx)
{
return 1;
}
char _license[] __attribute__((section("license"), used)) = "GPL";
int _version __attribute__((section("version"), used)) = 0x40300;
#
# ./perf record -e ./test_probe_glob.c ls /
...
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.013 MB perf.data ]
# ./perf evlist
perf_bpf_probe:func_1
perf_bpf_probe:func
After changing "inlines=no" to "inlines=yes":
# ./perf record -e ./test_probe_glob.c ls /
...
[ perf record: Woken up 2 times to write data ]
[ perf record: Captured and wrote 0.013 MB perf.data ]
# ./perf evlist
perf_bpf_probe:func_3
perf_bpf_probe:func_2
perf_bpf_probe:func_1
perf_bpf_probe:func
Then test 'force':
Use following program:
# cat test_probe_force.c
__attribute__((section("func=sys_write"), used))
int funca(void *ctx)
{
return 1;
}
__attribute__((section("force=yes;func=sys_write"), used))
int funcb(void *ctx)
{
return 1;
}
char _license[] __attribute__((section("license"), used)) = "GPL";
int _version __attribute__((section("version"), used)) = 0x40300;
#
# perf record -e ./test_probe_force.c usleep 1
Error: event "func" already exists.
Hint: Remove existing event by 'perf probe -d'
or force duplicates by 'perf probe -f'
or set 'force=yes' in BPF source.
event syntax error: './test_probe_force.c'
\___ Probe point exist. Try 'perf probe -d "*"' and set 'force=yes'
(add -v to see detail)
...
Then replace 'force=no' to 'force=yes':
# vim test_probe_force.c
# perf record -e ./test_probe_force.c usleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.017 MB perf.data ]
# perf evlist
perf_bpf_probe:func_1
perf_bpf_probe:func
#
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1447675815-166222-7-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/util/bpf-loader.c | 53 +++++++++++++++++++++++++++++++++++++++++--
tools/perf/util/probe-event.c | 7 ++++--
2 files changed, 56 insertions(+), 4 deletions(-)
diff --git a/tools/perf/util/bpf-loader.c b/tools/perf/util/bpf-loader.c
index d0f02ed93804..98f2e5d1a5be 100644
--- a/tools/perf/util/bpf-loader.c
+++ b/tools/perf/util/bpf-loader.c
@@ -7,6 +7,7 @@
#include <bpf/libbpf.h>
#include <linux/err.h>
+#include <linux/string.h>
#include "perf.h"
#include "debug.h"
#include "bpf-loader.h"
@@ -129,6 +130,38 @@ config__module(const char *value, struct perf_probe_event *pev)
return 0;
}
+static int
+config__bool(const char *value,
+ bool *pbool, bool invert)
+{
+ int err;
+ bool bool_value;
+
+ if (!pbool)
+ return -EINVAL;
+
+ err = strtobool(value, &bool_value);
+ if (err)
+ return err;
+
+ *pbool = invert ? !bool_value : bool_value;
+ return 0;
+}
+
+static int
+config__inlines(const char *value,
+ struct perf_probe_event *pev __maybe_unused)
+{
+ return config__bool(value, &probe_conf.no_inlines, true);
+}
+
+static int
+config__force(const char *value,
+ struct perf_probe_event *pev __maybe_unused)
+{
+ return config__bool(value, &probe_conf.force_add, false);
+}
+
static struct {
const char *key;
const char *usage;
@@ -146,7 +179,19 @@ static struct {
.usage = "module=<module name> ",
.desc = "Set kprobe module",
.func = config__module,
- }
+ },
+ {
+ .key = "inlines",
+ .usage = "inlines=[yes|no] ",
+ .desc = "Probe at inline symbol",
+ .func = config__inlines,
+ },
+ {
+ .key = "force",
+ .usage = "force=[yes|no] ",
+ .desc = "Forcibly add events with existing name",
+ .func = config__force,
+ },
};
static int
@@ -240,6 +285,10 @@ config_bpf_program(struct bpf_program *prog)
const char *config_str;
int err;
+ /* Initialize per-program probing setting */
+ probe_conf.no_inlines = false;
+ probe_conf.force_add = false;
+
config_str = bpf_program__title(prog, false);
if (IS_ERR(config_str)) {
pr_debug("bpf: unable to get title for program\n");
@@ -544,7 +593,7 @@ int bpf__strerror_probe(struct bpf_object *obj __maybe_unused,
scnprintf(buf, size, "%s (add -v to see detail)", emsg);
break;
}
- bpf__strerror_entry(EEXIST, "Probe point exist. Try use 'perf probe -d \"*\"'");
+ bpf__strerror_entry(EEXIST, "Probe point exist. Try 'perf probe -d \"*\"' and set 'force=yes'");
bpf__strerror_entry(EACCES, "You need to be root");
bpf__strerror_entry(EPERM, "You need to be root, and /proc/sys/kernel/kptr_restrict should be 0");
bpf__strerror_entry(ENOENT, "You need to check probing points in BPF file");
diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index 03875f9154e7..93996ec4bbe3 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -2326,8 +2326,11 @@ static int get_new_event_name(char *buf, size_t len, const char *base,
goto out;
if (!allow_suffix) {
- pr_warning("Error: event \"%s\" already exists. "
- "(Use -f to force duplicates.)\n", buf);
+ pr_warning("Error: event \"%s\" already exists.\n"
+ " Hint: Remove existing event by 'perf probe -d'\n"
+ " or force duplicates by 'perf probe -f'\n"
+ " or set 'force=yes' in BPF source.\n",
+ buf);
ret = -EEXIST;
goto out;
}
--
2.1.0
^ permalink raw reply related [flat|nested] 21+ messages in thread* [PATCH 09/16] perf bpf: Add prologue for BPF programs for fetching arguments
2015-11-17 15:31 [GIT PULL 00/16] perf/ebpf improvements and fixes Arnaldo Carvalho de Melo
` (7 preceding siblings ...)
2015-11-17 15:31 ` [PATCH 08/16] perf bpf: Allow BPF program config probing options Arnaldo Carvalho de Melo
@ 2015-11-17 15:31 ` Arnaldo Carvalho de Melo
2015-11-17 15:31 ` [PATCH 10/16] perf bpf: Generate prologue for BPF programs Arnaldo Carvalho de Melo
` (7 subsequent siblings)
16 siblings, 0 replies; 21+ messages in thread
From: Arnaldo Carvalho de Melo @ 2015-11-17 15:31 UTC (permalink / raw)
To: Ingo Molnar
Cc: linux-kernel, He Kuang, Alexei Starovoitov, Masami Hiramatsu,
Wang Nan, Zefan Li, pi3orama, Arnaldo Carvalho de Melo
From: He Kuang <hekuang@huawei.com>
This patch generates a prologue for a BPF program which fetches arguments for
it. With this patch, the program can have arguments as follow:
SEC("lock_page=__lock_page page->flags")
int lock_page(struct pt_regs *ctx, int err, unsigned long flags)
{
return 1;
}
This patch passes at most 3 arguments from r3, r4 and r5. r1 is still the ctx
pointer. r2 is used to indicate if dereferencing was done successfully.
This patch uses r6 to hold ctx (struct pt_regs) and r7 to hold stack pointer
for result. Result of each arguments first store on stack:
low address
BPF_REG_FP - 24 ARG3
BPF_REG_FP - 16 ARG2
BPF_REG_FP - 8 ARG1
BPF_REG_FP
high address
Then loaded into r3, r4 and r5.
The output prologue for offn(...off2(off1(reg)))) should be:
r6 <- r1 // save ctx into a callee saved register
r7 <- fp
r7 <- r7 - stack_offset // pointer to result slot
/* load r3 with the offset in pt_regs of 'reg' */
(r7) <- r3 // make slot valid
r3 <- r3 + off1 // prepare to read unsafe pointer
r2 <- 8
r1 <- r7 // result put onto stack
call probe_read // read unsafe pointer
jnei r0, 0, err // error checking
r3 <- (r7) // read result
r3 <- r3 + off2 // prepare to read unsafe pointer
r2 <- 8
r1 <- r7
call probe_read
jnei r0, 0, err
...
/* load r2, r3, r4 from stack */
goto success
err:
r2 <- 1
/* load r3, r4, r5 with 0 */
goto usercode
success:
r2 <- 0
usercode:
r1 <- r6 // restore ctx
// original user code
If all of arguments reside in register (dereferencing is not
required), gen_prologue_fastpath() will be used to create
fast prologue:
r3 <- (r1 + offset of reg1)
r4 <- (r1 + offset of reg2)
r5 <- (r1 + offset of reg3)
r2 <- 0
P.S.
eBPF calling convention is defined as:
* r0 - return value from in-kernel function, and exit value
for eBPF program
* r1 - r5 - arguments from eBPF program to in-kernel function
* r6 - r9 - callee saved registers that in-kernel function will
preserve
* r10 - read-only frame pointer to access stack
Committer note:
At least testing if it builds and loads:
# cat test_probe_arg.c
struct pt_regs;
__attribute__((section("lock_page=__lock_page page->flags"), used))
int func(struct pt_regs *ctx, int err, unsigned long flags)
{
return 1;
}
char _license[] __attribute__((section("license"), used)) = "GPL";
int _version __attribute__((section("version"), used)) = 0x40300;
# perf record -e ./test_probe_arg.c usleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.016 MB perf.data ]
# perf evlist
perf_bpf_probe:lock_page
#
Signed-off-by: He Kuang <hekuang@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1447675815-166222-11-git-send-email-wangnan0@huawei.com
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/util/Build | 1 +
tools/perf/util/bpf-loader.c | 3 +
tools/perf/util/bpf-loader.h | 3 +
tools/perf/util/bpf-prologue.c | 455 +++++++++++++++++++++++++++++++++++++++++
tools/perf/util/bpf-prologue.h | 34 +++
5 files changed, 496 insertions(+)
create mode 100644 tools/perf/util/bpf-prologue.c
create mode 100644 tools/perf/util/bpf-prologue.h
diff --git a/tools/perf/util/Build b/tools/perf/util/Build
index e2316900f96f..0513dd525d87 100644
--- a/tools/perf/util/Build
+++ b/tools/perf/util/Build
@@ -89,6 +89,7 @@ libperf-y += parse-branch-options.o
libperf-y += parse-regs-options.o
libperf-$(CONFIG_LIBBPF) += bpf-loader.o
+libperf-$(CONFIG_BPF_PROLOGUE) += bpf-prologue.o
libperf-$(CONFIG_LIBELF) += symbol-elf.o
libperf-$(CONFIG_LIBELF) += probe-file.o
libperf-$(CONFIG_LIBELF) += probe-event.o
diff --git a/tools/perf/util/bpf-loader.c b/tools/perf/util/bpf-loader.c
index 98f2e5d1a5be..bd14be438cda 100644
--- a/tools/perf/util/bpf-loader.c
+++ b/tools/perf/util/bpf-loader.c
@@ -509,6 +509,9 @@ static const char *bpf_loader_strerror_table[NR_ERRNO] = {
[ERRCODE_OFFSET(INTERNAL)] = "BPF loader internal error",
[ERRCODE_OFFSET(COMPILE)] = "Error when compiling BPF scriptlet",
[ERRCODE_OFFSET(CONFIG_TERM)] = "Invalid config term in config string",
+ [ERRCODE_OFFSET(PROLOGUE)] = "Failed to generate prologue",
+ [ERRCODE_OFFSET(PROLOGUE2BIG)] = "Prologue too big for program",
+ [ERRCODE_OFFSET(PROLOGUEOOB)] = "Offset out of bound for prologue",
};
static int
diff --git a/tools/perf/util/bpf-loader.h b/tools/perf/util/bpf-loader.h
index d19f5c5d6d74..a58740b0f31e 100644
--- a/tools/perf/util/bpf-loader.h
+++ b/tools/perf/util/bpf-loader.h
@@ -21,6 +21,9 @@ enum bpf_loader_errno {
BPF_LOADER_ERRNO__INTERNAL, /* BPF loader internal error */
BPF_LOADER_ERRNO__COMPILE, /* Error when compiling BPF scriptlet */
BPF_LOADER_ERRNO__CONFIG_TERM, /* Invalid config term in config term */
+ BPF_LOADER_ERRNO__PROLOGUE, /* Failed to generate prologue */
+ BPF_LOADER_ERRNO__PROLOGUE2BIG, /* Prologue too big for program */
+ BPF_LOADER_ERRNO__PROLOGUEOOB, /* Offset out of bound for prologue */
__BPF_LOADER_ERRNO__END,
};
diff --git a/tools/perf/util/bpf-prologue.c b/tools/perf/util/bpf-prologue.c
new file mode 100644
index 000000000000..6cdbee119ceb
--- /dev/null
+++ b/tools/perf/util/bpf-prologue.c
@@ -0,0 +1,455 @@
+/*
+ * bpf-prologue.c
+ *
+ * Copyright (C) 2015 He Kuang <hekuang@huawei.com>
+ * Copyright (C) 2015 Wang Nan <wangnan0@huawei.com>
+ * Copyright (C) 2015 Huawei Inc.
+ */
+
+#include <bpf/libbpf.h>
+#include "perf.h"
+#include "debug.h"
+#include "bpf-loader.h"
+#include "bpf-prologue.h"
+#include "probe-finder.h"
+#include <dwarf-regs.h>
+#include <linux/filter.h>
+
+#define BPF_REG_SIZE 8
+
+#define JMP_TO_ERROR_CODE -1
+#define JMP_TO_SUCCESS_CODE -2
+#define JMP_TO_USER_CODE -3
+
+struct bpf_insn_pos {
+ struct bpf_insn *begin;
+ struct bpf_insn *end;
+ struct bpf_insn *pos;
+};
+
+static inline int
+pos_get_cnt(struct bpf_insn_pos *pos)
+{
+ return pos->pos - pos->begin;
+}
+
+static int
+append_insn(struct bpf_insn new_insn, struct bpf_insn_pos *pos)
+{
+ if (!pos->pos)
+ return -BPF_LOADER_ERRNO__PROLOGUE2BIG;
+
+ if (pos->pos + 1 >= pos->end) {
+ pr_err("bpf prologue: prologue too long\n");
+ pos->pos = NULL;
+ return -BPF_LOADER_ERRNO__PROLOGUE2BIG;
+ }
+
+ *(pos->pos)++ = new_insn;
+ return 0;
+}
+
+static int
+check_pos(struct bpf_insn_pos *pos)
+{
+ if (!pos->pos || pos->pos >= pos->end)
+ return -BPF_LOADER_ERRNO__PROLOGUE2BIG;
+ return 0;
+}
+
+/* Give it a shorter name */
+#define ins(i, p) append_insn((i), (p))
+
+/*
+ * Give a register name (in 'reg'), generate instruction to
+ * load register into an eBPF register rd:
+ * 'ldd target_reg, offset(ctx_reg)', where:
+ * ctx_reg is pre initialized to pointer of 'struct pt_regs'.
+ */
+static int
+gen_ldx_reg_from_ctx(struct bpf_insn_pos *pos, int ctx_reg,
+ const char *reg, int target_reg)
+{
+ int offset = regs_query_register_offset(reg);
+
+ if (offset < 0) {
+ pr_err("bpf: prologue: failed to get register %s\n",
+ reg);
+ return offset;
+ }
+ ins(BPF_LDX_MEM(BPF_DW, target_reg, ctx_reg, offset), pos);
+
+ return check_pos(pos);
+}
+
+/*
+ * Generate a BPF_FUNC_probe_read function call.
+ *
+ * src_base_addr_reg is a register holding base address,
+ * dst_addr_reg is a register holding dest address (on stack),
+ * result is:
+ *
+ * *[dst_addr_reg] = *([src_base_addr_reg] + offset)
+ *
+ * Arguments of BPF_FUNC_probe_read:
+ * ARG1: ptr to stack (dest)
+ * ARG2: size (8)
+ * ARG3: unsafe ptr (src)
+ */
+static int
+gen_read_mem(struct bpf_insn_pos *pos,
+ int src_base_addr_reg,
+ int dst_addr_reg,
+ long offset)
+{
+ /* mov arg3, src_base_addr_reg */
+ if (src_base_addr_reg != BPF_REG_ARG3)
+ ins(BPF_MOV64_REG(BPF_REG_ARG3, src_base_addr_reg), pos);
+ /* add arg3, #offset */
+ if (offset)
+ ins(BPF_ALU64_IMM(BPF_ADD, BPF_REG_ARG3, offset), pos);
+
+ /* mov arg2, #reg_size */
+ ins(BPF_ALU64_IMM(BPF_MOV, BPF_REG_ARG2, BPF_REG_SIZE), pos);
+
+ /* mov arg1, dst_addr_reg */
+ if (dst_addr_reg != BPF_REG_ARG1)
+ ins(BPF_MOV64_REG(BPF_REG_ARG1, dst_addr_reg), pos);
+
+ /* Call probe_read */
+ ins(BPF_EMIT_CALL(BPF_FUNC_probe_read), pos);
+ /*
+ * Error processing: if read fail, goto error code,
+ * will be relocated. Target should be the start of
+ * error processing code.
+ */
+ ins(BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, JMP_TO_ERROR_CODE),
+ pos);
+
+ return check_pos(pos);
+}
+
+/*
+ * Each arg should be bare register. Fetch and save them into argument
+ * registers (r3 - r5).
+ *
+ * BPF_REG_1 should have been initialized with pointer to
+ * 'struct pt_regs'.
+ */
+static int
+gen_prologue_fastpath(struct bpf_insn_pos *pos,
+ struct probe_trace_arg *args, int nargs)
+{
+ int i, err = 0;
+
+ for (i = 0; i < nargs; i++) {
+ err = gen_ldx_reg_from_ctx(pos, BPF_REG_1, args[i].value,
+ BPF_PROLOGUE_START_ARG_REG + i);
+ if (err)
+ goto errout;
+ }
+
+ return check_pos(pos);
+errout:
+ return err;
+}
+
+/*
+ * Slow path:
+ * At least one argument has the form of 'offset($rx)'.
+ *
+ * Following code first stores them into stack, then loads all of then
+ * to r2 - r5.
+ * Before final loading, the final result should be:
+ *
+ * low address
+ * BPF_REG_FP - 24 ARG3
+ * BPF_REG_FP - 16 ARG2
+ * BPF_REG_FP - 8 ARG1
+ * BPF_REG_FP
+ * high address
+ *
+ * For each argument (described as: offn(...off2(off1(reg)))),
+ * generates following code:
+ *
+ * r7 <- fp
+ * r7 <- r7 - stack_offset // Ideal code should initialize r7 using
+ * // fp before generating args. However,
+ * // eBPF won't regard r7 as stack pointer
+ * // if it is generated by minus 8 from
+ * // another stack pointer except fp.
+ * // This is why we have to set r7
+ * // to fp for each variable.
+ * r3 <- value of 'reg'-> generated using gen_ldx_reg_from_ctx()
+ * (r7) <- r3 // skip following instructions for bare reg
+ * r3 <- r3 + off1 . // skip if off1 == 0
+ * r2 <- 8 \
+ * r1 <- r7 |-> generated by gen_read_mem()
+ * call probe_read /
+ * jnei r0, 0, err ./
+ * r3 <- (r7)
+ * r3 <- r3 + off2 . // skip if off2 == 0
+ * r2 <- 8 \ // r2 may be broken by probe_read, so set again
+ * r1 <- r7 |-> generated by gen_read_mem()
+ * call probe_read /
+ * jnei r0, 0, err ./
+ * ...
+ */
+static int
+gen_prologue_slowpath(struct bpf_insn_pos *pos,
+ struct probe_trace_arg *args, int nargs)
+{
+ int err, i;
+
+ for (i = 0; i < nargs; i++) {
+ struct probe_trace_arg *arg = &args[i];
+ const char *reg = arg->value;
+ struct probe_trace_arg_ref *ref = NULL;
+ int stack_offset = (i + 1) * -8;
+
+ pr_debug("prologue: fetch arg %d, base reg is %s\n",
+ i, reg);
+
+ /* value of base register is stored into ARG3 */
+ err = gen_ldx_reg_from_ctx(pos, BPF_REG_CTX, reg,
+ BPF_REG_ARG3);
+ if (err) {
+ pr_err("prologue: failed to get offset of register %s\n",
+ reg);
+ goto errout;
+ }
+
+ /* Make r7 the stack pointer. */
+ ins(BPF_MOV64_REG(BPF_REG_7, BPF_REG_FP), pos);
+ /* r7 += -8 */
+ ins(BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, stack_offset), pos);
+ /*
+ * Store r3 (base register) onto stack
+ * Ensure fp[offset] is set.
+ * fp is the only valid base register when storing
+ * into stack. We are not allowed to use r7 as base
+ * register here.
+ */
+ ins(BPF_STX_MEM(BPF_DW, BPF_REG_FP, BPF_REG_ARG3,
+ stack_offset), pos);
+
+ ref = arg->ref;
+ while (ref) {
+ pr_debug("prologue: arg %d: offset %ld\n",
+ i, ref->offset);
+ err = gen_read_mem(pos, BPF_REG_3, BPF_REG_7,
+ ref->offset);
+ if (err) {
+ pr_err("prologue: failed to generate probe_read function call\n");
+ goto errout;
+ }
+
+ ref = ref->next;
+ /*
+ * Load previous result into ARG3. Use
+ * BPF_REG_FP instead of r7 because verifier
+ * allows FP based addressing only.
+ */
+ if (ref)
+ ins(BPF_LDX_MEM(BPF_DW, BPF_REG_ARG3,
+ BPF_REG_FP, stack_offset), pos);
+ }
+ }
+
+ /* Final pass: read to registers */
+ for (i = 0; i < nargs; i++)
+ ins(BPF_LDX_MEM(BPF_DW, BPF_PROLOGUE_START_ARG_REG + i,
+ BPF_REG_FP, -BPF_REG_SIZE * (i + 1)), pos);
+
+ ins(BPF_JMP_IMM(BPF_JA, BPF_REG_0, 0, JMP_TO_SUCCESS_CODE), pos);
+
+ return check_pos(pos);
+errout:
+ return err;
+}
+
+static int
+prologue_relocate(struct bpf_insn_pos *pos, struct bpf_insn *error_code,
+ struct bpf_insn *success_code, struct bpf_insn *user_code)
+{
+ struct bpf_insn *insn;
+
+ if (check_pos(pos))
+ return -BPF_LOADER_ERRNO__PROLOGUE2BIG;
+
+ for (insn = pos->begin; insn < pos->pos; insn++) {
+ struct bpf_insn *target;
+ u8 class = BPF_CLASS(insn->code);
+ u8 opcode;
+
+ if (class != BPF_JMP)
+ continue;
+ opcode = BPF_OP(insn->code);
+ if (opcode == BPF_CALL)
+ continue;
+
+ switch (insn->off) {
+ case JMP_TO_ERROR_CODE:
+ target = error_code;
+ break;
+ case JMP_TO_SUCCESS_CODE:
+ target = success_code;
+ break;
+ case JMP_TO_USER_CODE:
+ target = user_code;
+ break;
+ default:
+ pr_err("bpf prologue: internal error: relocation failed\n");
+ return -BPF_LOADER_ERRNO__PROLOGUE;
+ }
+
+ insn->off = target - (insn + 1);
+ }
+ return 0;
+}
+
+int bpf__gen_prologue(struct probe_trace_arg *args, int nargs,
+ struct bpf_insn *new_prog, size_t *new_cnt,
+ size_t cnt_space)
+{
+ struct bpf_insn *success_code = NULL;
+ struct bpf_insn *error_code = NULL;
+ struct bpf_insn *user_code = NULL;
+ struct bpf_insn_pos pos;
+ bool fastpath = true;
+ int err = 0, i;
+
+ if (!new_prog || !new_cnt)
+ return -EINVAL;
+
+ if (cnt_space > BPF_MAXINSNS)
+ cnt_space = BPF_MAXINSNS;
+
+ pos.begin = new_prog;
+ pos.end = new_prog + cnt_space;
+ pos.pos = new_prog;
+
+ if (!nargs) {
+ ins(BPF_ALU64_IMM(BPF_MOV, BPF_PROLOGUE_FETCH_RESULT_REG, 0),
+ &pos);
+
+ if (check_pos(&pos))
+ goto errout;
+
+ *new_cnt = pos_get_cnt(&pos);
+ return 0;
+ }
+
+ if (nargs > BPF_PROLOGUE_MAX_ARGS) {
+ pr_warning("bpf: prologue: %d arguments are dropped\n",
+ nargs - BPF_PROLOGUE_MAX_ARGS);
+ nargs = BPF_PROLOGUE_MAX_ARGS;
+ }
+
+ /* First pass: validation */
+ for (i = 0; i < nargs; i++) {
+ struct probe_trace_arg_ref *ref = args[i].ref;
+
+ if (args[i].value[0] == '@') {
+ /* TODO: fetch global variable */
+ pr_err("bpf: prologue: global %s%+ld not support\n",
+ args[i].value, ref ? ref->offset : 0);
+ return -ENOTSUP;
+ }
+
+ while (ref) {
+ /* fastpath is true if all args has ref == NULL */
+ fastpath = false;
+
+ /*
+ * Instruction encodes immediate value using
+ * s32, ref->offset is long. On systems which
+ * can't fill long in s32, refuse to process if
+ * ref->offset too large (or small).
+ */
+#ifdef __LP64__
+#define OFFSET_MAX ((1LL << 31) - 1)
+#define OFFSET_MIN ((1LL << 31) * -1)
+ if (ref->offset > OFFSET_MAX ||
+ ref->offset < OFFSET_MIN) {
+ pr_err("bpf: prologue: offset out of bound: %ld\n",
+ ref->offset);
+ return -BPF_LOADER_ERRNO__PROLOGUEOOB;
+ }
+#endif
+ ref = ref->next;
+ }
+ }
+ pr_debug("prologue: pass validation\n");
+
+ if (fastpath) {
+ /* If all variables are registers... */
+ pr_debug("prologue: fast path\n");
+ err = gen_prologue_fastpath(&pos, args, nargs);
+ if (err)
+ goto errout;
+ } else {
+ pr_debug("prologue: slow path\n");
+
+ /* Initialization: move ctx to a callee saved register. */
+ ins(BPF_MOV64_REG(BPF_REG_CTX, BPF_REG_ARG1), &pos);
+
+ err = gen_prologue_slowpath(&pos, args, nargs);
+ if (err)
+ goto errout;
+ /*
+ * start of ERROR_CODE (only slow pass needs error code)
+ * mov r2 <- 1 // r2 is error number
+ * mov r3 <- 0 // r3, r4... should be touched or
+ * // verifier would complain
+ * mov r4 <- 0
+ * ...
+ * goto usercode
+ */
+ error_code = pos.pos;
+ ins(BPF_ALU64_IMM(BPF_MOV, BPF_PROLOGUE_FETCH_RESULT_REG, 1),
+ &pos);
+
+ for (i = 0; i < nargs; i++)
+ ins(BPF_ALU64_IMM(BPF_MOV,
+ BPF_PROLOGUE_START_ARG_REG + i,
+ 0),
+ &pos);
+ ins(BPF_JMP_IMM(BPF_JA, BPF_REG_0, 0, JMP_TO_USER_CODE),
+ &pos);
+ }
+
+ /*
+ * start of SUCCESS_CODE:
+ * mov r2 <- 0
+ * goto usercode // skip
+ */
+ success_code = pos.pos;
+ ins(BPF_ALU64_IMM(BPF_MOV, BPF_PROLOGUE_FETCH_RESULT_REG, 0), &pos);
+
+ /*
+ * start of USER_CODE:
+ * Restore ctx to r1
+ */
+ user_code = pos.pos;
+ if (!fastpath) {
+ /*
+ * Only slow path needs restoring of ctx. In fast path,
+ * register are loaded directly from r1.
+ */
+ ins(BPF_MOV64_REG(BPF_REG_ARG1, BPF_REG_CTX), &pos);
+ err = prologue_relocate(&pos, error_code, success_code,
+ user_code);
+ if (err)
+ goto errout;
+ }
+
+ err = check_pos(&pos);
+ if (err)
+ goto errout;
+
+ *new_cnt = pos_get_cnt(&pos);
+ return 0;
+errout:
+ return err;
+}
diff --git a/tools/perf/util/bpf-prologue.h b/tools/perf/util/bpf-prologue.h
new file mode 100644
index 000000000000..d94cbea12899
--- /dev/null
+++ b/tools/perf/util/bpf-prologue.h
@@ -0,0 +1,34 @@
+/*
+ * Copyright (C) 2015, He Kuang <hekuang@huawei.com>
+ * Copyright (C) 2015, Huawei Inc.
+ */
+#ifndef __BPF_PROLOGUE_H
+#define __BPF_PROLOGUE_H
+
+#include <linux/compiler.h>
+#include <linux/filter.h>
+#include "probe-event.h"
+
+#define BPF_PROLOGUE_MAX_ARGS 3
+#define BPF_PROLOGUE_START_ARG_REG BPF_REG_3
+#define BPF_PROLOGUE_FETCH_RESULT_REG BPF_REG_2
+
+#ifdef HAVE_BPF_PROLOGUE
+int bpf__gen_prologue(struct probe_trace_arg *args, int nargs,
+ struct bpf_insn *new_prog, size_t *new_cnt,
+ size_t cnt_space);
+#else
+static inline int
+bpf__gen_prologue(struct probe_trace_arg *args __maybe_unused,
+ int nargs __maybe_unused,
+ struct bpf_insn *new_prog __maybe_unused,
+ size_t *new_cnt,
+ size_t cnt_space __maybe_unused)
+{
+ if (!new_cnt)
+ return -EINVAL;
+ *new_cnt = 0;
+ return -ENOTSUP;
+}
+#endif
+#endif /* __BPF_PROLOGUE_H */
--
2.1.0
^ permalink raw reply related [flat|nested] 21+ messages in thread* [PATCH 10/16] perf bpf: Generate prologue for BPF programs
2015-11-17 15:31 [GIT PULL 00/16] perf/ebpf improvements and fixes Arnaldo Carvalho de Melo
` (8 preceding siblings ...)
2015-11-17 15:31 ` [PATCH 09/16] perf bpf: Add prologue for BPF programs for fetching arguments Arnaldo Carvalho de Melo
@ 2015-11-17 15:31 ` Arnaldo Carvalho de Melo
2015-11-17 15:31 ` [PATCH 11/16] perf test: Test the BPF prologue adding infrastructure Arnaldo Carvalho de Melo
` (6 subsequent siblings)
16 siblings, 0 replies; 21+ messages in thread
From: Arnaldo Carvalho de Melo @ 2015-11-17 15:31 UTC (permalink / raw)
To: Ingo Molnar
Cc: linux-kernel, Wang Nan, Alexei Starovoitov, Masami Hiramatsu,
Zefan Li, pi3orama, Arnaldo Carvalho de Melo
From: Wang Nan <wangnan0@huawei.com>
This patch generates a prologue for each 'struct probe_trace_event' for
fetching arguments for BPF programs.
After bpf__probe(), iterate over each program to check whether prologues are
required. If none of the 'struct perf_probe_event' programs will attach to have
at least one argument, simply skip preprocessor hooking. For those who a
prologue is required, call bpf__gen_prologue() and paste the original
instruction after the prologue.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1447675815-166222-12-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/util/bpf-loader.c | 120 ++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 119 insertions(+), 1 deletion(-)
diff --git a/tools/perf/util/bpf-loader.c b/tools/perf/util/bpf-loader.c
index bd14be438cda..190a1c7f0649 100644
--- a/tools/perf/util/bpf-loader.c
+++ b/tools/perf/util/bpf-loader.c
@@ -5,12 +5,15 @@
* Copyright (C) 2015 Huawei Inc.
*/
+#include <linux/bpf.h>
#include <bpf/libbpf.h>
#include <linux/err.h>
#include <linux/string.h>
#include "perf.h"
#include "debug.h"
#include "bpf-loader.h"
+#include "bpf-prologue.h"
+#include "llvm-utils.h"
#include "probe-event.h"
#include "probe-finder.h" // for MAX_PROBES
#include "llvm-utils.h"
@@ -33,6 +36,8 @@ DEFINE_PRINT_FN(debug, 1)
struct bpf_prog_priv {
struct perf_probe_event pev;
+ bool need_prologue;
+ struct bpf_insn *insns_buf;
};
static bool libbpf_initialized;
@@ -107,6 +112,7 @@ bpf_prog_priv__clear(struct bpf_program *prog __maybe_unused,
struct bpf_prog_priv *priv = _priv;
cleanup_perf_probe_events(&priv->pev, 1);
+ zfree(&priv->insns_buf);
free(priv);
}
@@ -365,6 +371,102 @@ static int bpf__prepare_probe(void)
return err;
}
+static int
+preproc_gen_prologue(struct bpf_program *prog, int n,
+ struct bpf_insn *orig_insns, int orig_insns_cnt,
+ struct bpf_prog_prep_result *res)
+{
+ struct probe_trace_event *tev;
+ struct perf_probe_event *pev;
+ struct bpf_prog_priv *priv;
+ struct bpf_insn *buf;
+ size_t prologue_cnt = 0;
+ int err;
+
+ err = bpf_program__get_private(prog, (void **)&priv);
+ if (err || !priv)
+ goto errout;
+
+ pev = &priv->pev;
+
+ if (n < 0 || n >= pev->ntevs)
+ goto errout;
+
+ tev = &pev->tevs[n];
+
+ buf = priv->insns_buf;
+ err = bpf__gen_prologue(tev->args, tev->nargs,
+ buf, &prologue_cnt,
+ BPF_MAXINSNS - orig_insns_cnt);
+ if (err) {
+ const char *title;
+
+ title = bpf_program__title(prog, false);
+ if (!title)
+ title = "[unknown]";
+
+ pr_debug("Failed to generate prologue for program %s\n",
+ title);
+ return err;
+ }
+
+ memcpy(&buf[prologue_cnt], orig_insns,
+ sizeof(struct bpf_insn) * orig_insns_cnt);
+
+ res->new_insn_ptr = buf;
+ res->new_insn_cnt = prologue_cnt + orig_insns_cnt;
+ res->pfd = NULL;
+ return 0;
+
+errout:
+ pr_debug("Internal error in preproc_gen_prologue\n");
+ return -BPF_LOADER_ERRNO__PROLOGUE;
+}
+
+static int hook_load_preprocessor(struct bpf_program *prog)
+{
+ struct perf_probe_event *pev;
+ struct bpf_prog_priv *priv;
+ bool need_prologue = false;
+ int err, i;
+
+ err = bpf_program__get_private(prog, (void **)&priv);
+ if (err || !priv) {
+ pr_debug("Internal error when hook preprocessor\n");
+ return -BPF_LOADER_ERRNO__INTERNAL;
+ }
+
+ pev = &priv->pev;
+ for (i = 0; i < pev->ntevs; i++) {
+ struct probe_trace_event *tev = &pev->tevs[i];
+
+ if (tev->nargs > 0) {
+ need_prologue = true;
+ break;
+ }
+ }
+
+ /*
+ * Since all tevs don't have argument, we don't need generate
+ * prologue.
+ */
+ if (!need_prologue) {
+ priv->need_prologue = false;
+ return 0;
+ }
+
+ priv->need_prologue = true;
+ priv->insns_buf = malloc(sizeof(struct bpf_insn) * BPF_MAXINSNS);
+ if (!priv->insns_buf) {
+ pr_debug("No enough memory: alloc insns_buf failed\n");
+ return -ENOMEM;
+ }
+
+ err = bpf_program__set_prep(prog, pev->ntevs,
+ preproc_gen_prologue);
+ return err;
+}
+
int bpf__probe(struct bpf_object *obj)
{
int err = 0;
@@ -399,6 +501,18 @@ int bpf__probe(struct bpf_object *obj)
pr_debug("bpf_probe: failed to apply perf probe events");
goto out;
}
+
+ /*
+ * After probing, let's consider prologue, which
+ * adds program fetcher to BPF programs.
+ *
+ * hook_load_preprocessorr() hooks pre-processor
+ * to bpf_program, let it generate prologue
+ * dynamically during loading.
+ */
+ err = hook_load_preprocessor(prog);
+ if (err)
+ goto out;
}
out:
return err < 0 ? err : 0;
@@ -482,7 +596,11 @@ int bpf__foreach_tev(struct bpf_object *obj,
for (i = 0; i < pev->ntevs; i++) {
tev = &pev->tevs[i];
- fd = bpf_program__fd(prog);
+ if (priv->need_prologue)
+ fd = bpf_program__nth_fd(prog, i);
+ else
+ fd = bpf_program__fd(prog);
+
if (fd < 0) {
pr_debug("bpf: failed to get file descriptor\n");
return fd;
--
2.1.0
^ permalink raw reply related [flat|nested] 21+ messages in thread* [PATCH 11/16] perf test: Test the BPF prologue adding infrastructure
2015-11-17 15:31 [GIT PULL 00/16] perf/ebpf improvements and fixes Arnaldo Carvalho de Melo
` (9 preceding siblings ...)
2015-11-17 15:31 ` [PATCH 10/16] perf bpf: Generate prologue for BPF programs Arnaldo Carvalho de Melo
@ 2015-11-17 15:31 ` Arnaldo Carvalho de Melo
2015-11-17 15:31 ` [PATCH 12/16] perf test: Fix 'perf test BPF' when it fails to find a suitable vmlinux Arnaldo Carvalho de Melo
` (5 subsequent siblings)
16 siblings, 0 replies; 21+ messages in thread
From: Arnaldo Carvalho de Melo @ 2015-11-17 15:31 UTC (permalink / raw)
To: Ingo Molnar
Cc: linux-kernel, Wang Nan, Alexei Starovoitov, Masami Hiramatsu,
Zefan Li, pi3orama, Arnaldo Carvalho de Melo
From: Wang Nan <wangnan0@huawei.com>
This patch introduces a new BPF script to test the BPF prologue adding
routines. The new script probes at null_lseek, which is the function pointer
used when we try to lseek on '/dev/null'.
The null_lseek function is chosen because it is used by function pointers, so
we don't need to consider inlining and LTO.
By extracting file->f_mode, bpf-script-test-prologue.c should know whether the
file is writable or readonly. According to llseek_loop() and
bpf-script-test-prologue.c, one fourth of total lseeks should be collected.
Committer note:
Testing it:
# perf test -v BPF
<SNIP>
Kernel build dir is set to /lib/modules/4.3.0+/build
set env: KBUILD_DIR=/lib/modules/4.3.0+/build
unset env: KBUILD_OPTS
include option is set to -nostdinc -isystem /usr/lib/gcc/x86_64-redhat-linux/4.9.2/include -I/home/git/linux/arch/x86/include -Iarch/x86/include/generated/uapi -Iarch/x86/include/generated -I/home/git/linux/include -Iinclude -I/home/git/linux/arch/x86/include/uapi -Iarch/x86/include/generated/uapi -I/home/git/linux/include/uapi -Iinclude/generated/uapi -include /home/git/linux/include/linux/kconfig.h
set env: NR_CPUS=4
set env: LINUX_VERSION_CODE=0x40300
set env: CLANG_EXEC=/usr/libexec/icecc/bin/clang
set env: CLANG_OPTIONS=-xc
set env: KERNEL_INC_OPTIONS= -nostdinc -isystem /usr/lib/gcc/x86_64-redhat-linux/4.9.2/include -I/home/git/linux/arch/x86/include -Iarch/x86/include/generated/uapi -Iarch/x86/include/generated -I/home/git/linux/include -Iinclude -I/home/git/linux/arch/x86/include/uapi -Iarch/x86/include/generated/uapi -I/home/git/linux/include/uapi -Iinclude/generated/uapi -include /home/git/linux/include/linux/kconfig.h
set env: WORKING_DIR=/lib/modules/4.3.0+/build
set env: CLANG_SOURCE=-
llvm compiling command template: echo '/*
* bpf-script-test-prologue.c
* Test BPF prologue
*/
#ifndef LINUX_VERSION_CODE
# error Need LINUX_VERSION_CODE
# error Example: for 4.2 kernel, put 'clang-opt="-DLINUX_VERSION_CODE=0x40200" into llvm section of ~/.perfconfig'
#endif
#define SEC(NAME) __attribute__((section(NAME), used))
#include <uapi/linux/fs.h>
#define FMODE_READ 0x1
#define FMODE_WRITE 0x2
static void (*bpf_trace_printk)(const char *fmt, int fmt_size, ...) =
(void *) 6;
SEC("func=null_lseek file->f_mode offset orig")
int bpf_func__null_lseek(void *ctx, int err, unsigned long f_mode,
unsigned long offset, unsigned long orig)
{
if (err)
return 0;
if (f_mode & FMODE_WRITE)
return 0;
if (offset & 1)
return 0;
if (orig == SEEK_CUR)
return 0;
return 1;
}
char _license[] SEC("license") = "GPL";
int _version SEC("version") = LINUX_VERSION_CODE;
' | $CLANG_EXEC -D__KERNEL__ -D__NR_CPUS__=$NR_CPUS -DLINUX_VERSION_CODE=$LINUX_VERSION_CODE $CLANG_OPTIONS $KERNEL_INC_OPTIONS -Wno-unused-value -Wno-pointer-sign -working-directory $WORKING_DIR -c "$CLANG_SOURCE" -target bpf -O2 -o -
libbpf: loading object '[bpf_prologue_test]' from buffer
libbpf: section .strtab, size 135, link 0, flags 0, type=3
libbpf: section .text, size 0, link 0, flags 6, type=1
libbpf: section .data, size 0, link 0, flags 3, type=1
libbpf: section .bss, size 0, link 0, flags 3, type=8
libbpf: section func=null_lseek file->f_mode offset orig, size 112, link 0, flags 6, type=1
libbpf: found program func=null_lseek file->f_mode offset orig
libbpf: section license, size 4, link 0, flags 3, type=1
libbpf: license of [bpf_prologue_test] is GPL
libbpf: section version, size 4, link 0, flags 3, type=1
libbpf: kernel version of [bpf_prologue_test] is 40300
libbpf: section .symtab, size 168, link 1, flags 0, type=2
bpf: config program 'func=null_lseek file->f_mode offset orig'
symbol:null_lseek file:(null) line:0 offset:0 return:0 lazy:(null)
parsing arg: file->f_mode into file, f_mode(1)
parsing arg: offset into offset
parsing arg: orig into orig
bpf: config 'func=null_lseek file->f_mode offset orig' is ok
Looking at the vmlinux_path (7 entries long)
Using /lib/modules/4.3.0+/build/vmlinux for symbols
Open Debuginfo file: /lib/modules/4.3.0+/build/vmlinux
Try to find probe point from debuginfo.
Matched function: null_lseek
Probe point found: null_lseek+0
Searching 'file' variable in context.
Converting variable file into trace event.
converting f_mode in file
f_mode type is unsigned int.
Searching 'offset' variable in context.
Converting variable offset into trace event.
offset type is long long int.
Searching 'orig' variable in context.
Converting variable orig into trace event.
orig type is int.
Found 1 probe_trace_events.
Opening /sys/kernel/debug/tracing//kprobe_events write=1
Writing event: p:perf_bpf_probe/func _text+4840528 f_mode=+68(%di):u32 offset=%si:s64 orig=%dx:s32
libbpf: don't need create maps for [bpf_prologue_test]
prologue: pass validation
prologue: slow path
prologue: fetch arg 0, base reg is %di
prologue: arg 0: offset 68
prologue: fetch arg 1, base reg is %si
prologue: fetch arg 2, base reg is %dx
add bpf event perf_bpf_probe:func and attach bpf program 3
adding perf_bpf_probe:func
adding perf_bpf_probe:func to 0x51672c0
mmap size 1052672B
Opening /sys/kernel/debug/tracing//kprobe_events write=1
Opening /sys/kernel/debug/tracing//uprobe_events write=1
Parsing probe_events: p:perf_bpf_probe/func _text+4840528 f_mode=+68(%di):u32 offset=%si:s64 orig=%dx:s32
Group:perf_bpf_probe Event:func probe:p
Writing event: -:perf_bpf_probe/func
test child finished with 0
---- end ----
Test BPF filter: Ok
#
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1447675815-166222-13-git-send-email-wangnan0@huawei.com
[ Added tools/perf/tests/llvm-src-prologue.c to .gitignore ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/tests/.gitignore | 1 +
tools/perf/tests/Build | 9 +++++++-
tools/perf/tests/bpf-script-test-prologue.c | 35 +++++++++++++++++++++++++++++
tools/perf/tests/bpf.c | 34 ++++++++++++++++++++++++++++
tools/perf/tests/llvm.c | 4 ++++
tools/perf/tests/llvm.h | 2 ++
6 files changed, 84 insertions(+), 1 deletion(-)
create mode 100644 tools/perf/tests/bpf-script-test-prologue.c
diff --git a/tools/perf/tests/.gitignore b/tools/perf/tests/.gitignore
index 489fc9ffbcb0..bf016c439fbd 100644
--- a/tools/perf/tests/.gitignore
+++ b/tools/perf/tests/.gitignore
@@ -1,2 +1,3 @@
llvm-src-base.c
llvm-src-kbuild.c
+llvm-src-prologue.c
diff --git a/tools/perf/tests/Build b/tools/perf/tests/Build
index f41ebf8849fe..0ff8a973b81c 100644
--- a/tools/perf/tests/Build
+++ b/tools/perf/tests/Build
@@ -31,7 +31,7 @@ perf-y += sample-parsing.o
perf-y += parse-no-sample-id-all.o
perf-y += kmod-path.o
perf-y += thread-map.o
-perf-y += llvm.o llvm-src-base.o llvm-src-kbuild.o
+perf-y += llvm.o llvm-src-base.o llvm-src-kbuild.o llvm-src-prologue.o
perf-y += bpf.o
perf-y += topology.o
@@ -49,6 +49,13 @@ $(OUTPUT)tests/llvm-src-kbuild.c: tests/bpf-script-test-kbuild.c
$(Q)sed -e 's/"/\\"/g' -e 's/\(.*\)/"\1\\n"/g' $< >> $@
$(Q)echo ';' >> $@
+$(OUTPUT)tests/llvm-src-prologue.c: tests/bpf-script-test-prologue.c
+ $(call rule_mkdir)
+ $(Q)echo '#include <tests/llvm.h>' > $@
+ $(Q)echo 'const char test_llvm__bpf_test_prologue_prog[] =' >> $@
+ $(Q)sed -e 's/"/\\"/g' -e 's/\(.*\)/"\1\\n"/g' $< >> $@
+ $(Q)echo ';' >> $@
+
ifeq ($(ARCH),$(filter $(ARCH),x86 arm arm64))
perf-$(CONFIG_DWARF_UNWIND) += dwarf-unwind.o
endif
diff --git a/tools/perf/tests/bpf-script-test-prologue.c b/tools/perf/tests/bpf-script-test-prologue.c
new file mode 100644
index 000000000000..7230e62c70fc
--- /dev/null
+++ b/tools/perf/tests/bpf-script-test-prologue.c
@@ -0,0 +1,35 @@
+/*
+ * bpf-script-test-prologue.c
+ * Test BPF prologue
+ */
+#ifndef LINUX_VERSION_CODE
+# error Need LINUX_VERSION_CODE
+# error Example: for 4.2 kernel, put 'clang-opt="-DLINUX_VERSION_CODE=0x40200" into llvm section of ~/.perfconfig'
+#endif
+#define SEC(NAME) __attribute__((section(NAME), used))
+
+#include <uapi/linux/fs.h>
+
+#define FMODE_READ 0x1
+#define FMODE_WRITE 0x2
+
+static void (*bpf_trace_printk)(const char *fmt, int fmt_size, ...) =
+ (void *) 6;
+
+SEC("func=null_lseek file->f_mode offset orig")
+int bpf_func__null_lseek(void *ctx, int err, unsigned long f_mode,
+ unsigned long offset, unsigned long orig)
+{
+ if (err)
+ return 0;
+ if (f_mode & FMODE_WRITE)
+ return 0;
+ if (offset & 1)
+ return 0;
+ if (orig == SEEK_CUR)
+ return 0;
+ return 1;
+}
+
+char _license[] SEC("license") = "GPL";
+int _version SEC("version") = LINUX_VERSION_CODE;
diff --git a/tools/perf/tests/bpf.c b/tools/perf/tests/bpf.c
index ec16f7812c8b..c7131fa448e8 100644
--- a/tools/perf/tests/bpf.c
+++ b/tools/perf/tests/bpf.c
@@ -19,6 +19,29 @@ static int epoll_pwait_loop(void)
return 0;
}
+#ifdef HAVE_BPF_PROLOGUE
+
+static int llseek_loop(void)
+{
+ int fds[2], i;
+
+ fds[0] = open("/dev/null", O_RDONLY);
+ fds[1] = open("/dev/null", O_RDWR);
+
+ if (fds[0] < 0 || fds[1] < 0)
+ return -1;
+
+ for (i = 0; i < NR_ITERS; i++) {
+ lseek(fds[i % 2], i, (i / 2) % 2 ? SEEK_CUR : SEEK_SET);
+ lseek(fds[(i + 1) % 2], i, (i / 2) % 2 ? SEEK_CUR : SEEK_SET);
+ }
+ close(fds[0]);
+ close(fds[1]);
+ return 0;
+}
+
+#endif
+
static struct {
enum test_llvm__testcase prog_id;
const char *desc;
@@ -37,6 +60,17 @@ static struct {
&epoll_pwait_loop,
(NR_ITERS + 1) / 2,
},
+#ifdef HAVE_BPF_PROLOGUE
+ {
+ LLVM_TESTCASE_BPF_PROLOGUE,
+ "Test BPF prologue generation",
+ "[bpf_prologue_test]",
+ "fix kbuild first",
+ "check your vmlinux setting?",
+ &llseek_loop,
+ (NR_ITERS + 1) / 4,
+ },
+#endif
};
static int do_test(struct bpf_object *obj, int (*func)(void),
diff --git a/tools/perf/tests/llvm.c b/tools/perf/tests/llvm.c
index bc4cf507cde5..7f4f7f79ca2f 100644
--- a/tools/perf/tests/llvm.c
+++ b/tools/perf/tests/llvm.c
@@ -44,6 +44,10 @@ static struct {
.source = test_llvm__bpf_test_kbuild_prog,
.desc = "Test kbuild searching",
},
+ [LLVM_TESTCASE_BPF_PROLOGUE] = {
+ .source = test_llvm__bpf_test_prologue_prog,
+ .desc = "Test BPF prologue generation",
+ },
};
diff --git a/tools/perf/tests/llvm.h b/tools/perf/tests/llvm.h
index d91d8f44efee..5150b4d6ef50 100644
--- a/tools/perf/tests/llvm.h
+++ b/tools/perf/tests/llvm.h
@@ -6,10 +6,12 @@
extern const char test_llvm__bpf_base_prog[];
extern const char test_llvm__bpf_test_kbuild_prog[];
+extern const char test_llvm__bpf_test_prologue_prog[];
enum test_llvm__testcase {
LLVM_TESTCASE_BASE,
LLVM_TESTCASE_KBUILD,
+ LLVM_TESTCASE_BPF_PROLOGUE,
__LLVM_TESTCASE_MAX,
};
--
2.1.0
^ permalink raw reply related [flat|nested] 21+ messages in thread* [PATCH 12/16] perf test: Fix 'perf test BPF' when it fails to find a suitable vmlinux
2015-11-17 15:31 [GIT PULL 00/16] perf/ebpf improvements and fixes Arnaldo Carvalho de Melo
` (10 preceding siblings ...)
2015-11-17 15:31 ` [PATCH 11/16] perf test: Test the BPF prologue adding infrastructure Arnaldo Carvalho de Melo
@ 2015-11-17 15:31 ` Arnaldo Carvalho de Melo
2015-11-17 15:31 ` [PATCH 13/16] perf bpf: Use same BPF program if arguments are identical Arnaldo Carvalho de Melo
` (4 subsequent siblings)
16 siblings, 0 replies; 21+ messages in thread
From: Arnaldo Carvalho de Melo @ 2015-11-17 15:31 UTC (permalink / raw)
To: Ingo Molnar
Cc: linux-kernel, Wang Nan, Alexei Starovoitov, Masami Hiramatsu,
Zefan Li, pi3orama, Arnaldo Carvalho de Melo
From: Wang Nan <wangnan0@huawei.com>
Two bugs in 'perf test BPF' are found when testing BPF prologue without
vmlinux:
# mv /lib/modules/4.3.0-rc4+/build/vmlinux{,.bak}
# ./perf test BPF
37: Test BPF filter :Failed to find the path for kernel: No such file or directory
Ok
Test BPF should fail in this case.
After this patch:
# ./perf test BPF
37: Test BPF filter :Failed to find the path for kernel: No such file or directory
FAILED!
# mv /lib/modules/4.3.0-rc4+/build/vmlinux{.bak,}
# ./perf test BPF
37: Test BPF filter : Ok
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1447749170-175898-2-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/tests/bpf.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/tools/perf/tests/bpf.c b/tools/perf/tests/bpf.c
index c7131fa448e8..dca3998883ee 100644
--- a/tools/perf/tests/bpf.c
+++ b/tools/perf/tests/bpf.c
@@ -102,8 +102,7 @@ static int do_test(struct bpf_object *obj, int (*func)(void),
err = parse_events_load_bpf_obj(&parse_evlist, &parse_evlist.list, obj);
if (err || list_empty(&parse_evlist.list)) {
pr_debug("Failed to add events selected by BPF\n");
- if (!err)
- return TEST_FAIL;
+ return TEST_FAIL;
}
snprintf(pid, sizeof(pid), "%d", getpid());
@@ -157,8 +156,10 @@ static int do_test(struct bpf_object *obj, int (*func)(void),
}
}
- if (count != expect)
+ if (count != expect) {
pr_debug("BPF filter result incorrect\n");
+ goto out_delete_evlist;
+ }
ret = TEST_OK;
--
2.1.0
^ permalink raw reply related [flat|nested] 21+ messages in thread* [PATCH 13/16] perf bpf: Use same BPF program if arguments are identical
2015-11-17 15:31 [GIT PULL 00/16] perf/ebpf improvements and fixes Arnaldo Carvalho de Melo
` (11 preceding siblings ...)
2015-11-17 15:31 ` [PATCH 12/16] perf test: Fix 'perf test BPF' when it fails to find a suitable vmlinux Arnaldo Carvalho de Melo
@ 2015-11-17 15:31 ` Arnaldo Carvalho de Melo
2015-11-17 15:31 ` [PATCH 14/16] perf test: Print result for each LLVM subtest Arnaldo Carvalho de Melo
` (3 subsequent siblings)
16 siblings, 0 replies; 21+ messages in thread
From: Arnaldo Carvalho de Melo @ 2015-11-17 15:31 UTC (permalink / raw)
To: Ingo Molnar
Cc: linux-kernel, Wang Nan, Alexei Starovoitov, Masami Hiramatsu,
Zefan Li, pi3orama, Arnaldo Carvalho de Melo
From: Wang Nan <wangnan0@huawei.com>
This patch allows creating only one BPF program for different
'probe_trace_event'(tev) entries generated by one
'perf_probe_event'(pev) if their prologues are identical.
This is done by comparing the argument list of different tev instances,
and the maps type of prologue and tev using a mapping array. This patch
utilizes qsort to sort the tevs. After sorting, tevs with identical
argument lists will be grouped together.
Test result:
Sample BPF program:
#define SEC(NAME) __attribute__((section(NAME), used))
SEC("inlines=no;"
"func=SyS_dup? oldfd")
int func(void *ctx)
{
return 1;
}
It would probe at SyS_dup2 and SyS_dup3, obtaining oldfd as its
argument.
The following cmdline shows a BPF program being loaded into the kernel
by perf:
# perf record -e ./test_bpf_arg.c sleep 4 & sleep 1 && ls /proc/$!/fd/ -l | grep bpf-prog
Before this patch:
# perf record -e ./test_bpf_arg.c sleep 4 & sleep 1 && ls /proc/$!/fd/ -l | grep bpf-prog
[1] 24858
lrwx------ 1 root root 64 Nov 14 04:09 3 -> anon_inode:bpf-prog
lrwx------ 1 root root 64 Nov 14 04:09 4 -> anon_inode:bpf-prog
...
After this patch:
# perf record -e ./test_bpf_arg.c sleep 4 & sleep 1 && ls /proc/$!/fd/ -l | grep bpf-prog
[1] 25699
lrwx------ 1 root root 64 Nov 14 04:10 3 -> anon_inode:bpf-prog
...
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1447749170-175898-3-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/util/bpf-loader.c | 138 ++++++++++++++++++++++++++++++++++++++++---
1 file changed, 131 insertions(+), 7 deletions(-)
diff --git a/tools/perf/util/bpf-loader.c b/tools/perf/util/bpf-loader.c
index 190a1c7f0649..36544e5ece43 100644
--- a/tools/perf/util/bpf-loader.c
+++ b/tools/perf/util/bpf-loader.c
@@ -38,6 +38,8 @@ struct bpf_prog_priv {
struct perf_probe_event pev;
bool need_prologue;
struct bpf_insn *insns_buf;
+ int nr_types;
+ int *type_mapping;
};
static bool libbpf_initialized;
@@ -113,6 +115,7 @@ bpf_prog_priv__clear(struct bpf_program *prog __maybe_unused,
cleanup_perf_probe_events(&priv->pev, 1);
zfree(&priv->insns_buf);
+ zfree(&priv->type_mapping);
free(priv);
}
@@ -381,7 +384,7 @@ preproc_gen_prologue(struct bpf_program *prog, int n,
struct bpf_prog_priv *priv;
struct bpf_insn *buf;
size_t prologue_cnt = 0;
- int err;
+ int i, err;
err = bpf_program__get_private(prog, (void **)&priv);
if (err || !priv)
@@ -389,10 +392,21 @@ preproc_gen_prologue(struct bpf_program *prog, int n,
pev = &priv->pev;
- if (n < 0 || n >= pev->ntevs)
+ if (n < 0 || n >= priv->nr_types)
goto errout;
- tev = &pev->tevs[n];
+ /* Find a tev belongs to that type */
+ for (i = 0; i < pev->ntevs; i++) {
+ if (priv->type_mapping[i] == n)
+ break;
+ }
+
+ if (i >= pev->ntevs) {
+ pr_debug("Internal error: prologue type %d not found\n", n);
+ return -BPF_LOADER_ERRNO__PROLOGUE;
+ }
+
+ tev = &pev->tevs[i];
buf = priv->insns_buf;
err = bpf__gen_prologue(tev->args, tev->nargs,
@@ -423,6 +437,101 @@ errout:
return -BPF_LOADER_ERRNO__PROLOGUE;
}
+/*
+ * compare_tev_args is reflexive, transitive and antisymmetric.
+ * I can proof it but this margin is too narrow to contain.
+ */
+static int compare_tev_args(const void *ptev1, const void *ptev2)
+{
+ int i, ret;
+ const struct probe_trace_event *tev1 =
+ *(const struct probe_trace_event **)ptev1;
+ const struct probe_trace_event *tev2 =
+ *(const struct probe_trace_event **)ptev2;
+
+ ret = tev2->nargs - tev1->nargs;
+ if (ret)
+ return ret;
+
+ for (i = 0; i < tev1->nargs; i++) {
+ struct probe_trace_arg *arg1, *arg2;
+ struct probe_trace_arg_ref *ref1, *ref2;
+
+ arg1 = &tev1->args[i];
+ arg2 = &tev2->args[i];
+
+ ret = strcmp(arg1->value, arg2->value);
+ if (ret)
+ return ret;
+
+ ref1 = arg1->ref;
+ ref2 = arg2->ref;
+
+ while (ref1 && ref2) {
+ ret = ref2->offset - ref1->offset;
+ if (ret)
+ return ret;
+
+ ref1 = ref1->next;
+ ref2 = ref2->next;
+ }
+
+ if (ref1 || ref2)
+ return ref2 ? 1 : -1;
+ }
+
+ return 0;
+}
+
+/*
+ * Assign a type number to each tevs in a pev.
+ * mapping is an array with same slots as tevs in that pev.
+ * nr_types will be set to number of types.
+ */
+static int map_prologue(struct perf_probe_event *pev, int *mapping,
+ int *nr_types)
+{
+ int i, type = 0;
+ struct probe_trace_event **ptevs;
+
+ size_t array_sz = sizeof(*ptevs) * pev->ntevs;
+
+ ptevs = malloc(array_sz);
+ if (!ptevs) {
+ pr_debug("No ehough memory: alloc ptevs failed\n");
+ return -ENOMEM;
+ }
+
+ pr_debug("In map_prologue, ntevs=%d\n", pev->ntevs);
+ for (i = 0; i < pev->ntevs; i++)
+ ptevs[i] = &pev->tevs[i];
+
+ qsort(ptevs, pev->ntevs, sizeof(*ptevs),
+ compare_tev_args);
+
+ for (i = 0; i < pev->ntevs; i++) {
+ int n;
+
+ n = ptevs[i] - pev->tevs;
+ if (i == 0) {
+ mapping[n] = type;
+ pr_debug("mapping[%d]=%d\n", n, type);
+ continue;
+ }
+
+ if (compare_tev_args(ptevs + i, ptevs + i - 1) == 0)
+ mapping[n] = type;
+ else
+ mapping[n] = ++type;
+
+ pr_debug("mapping[%d]=%d\n", n, mapping[n]);
+ }
+ free(ptevs);
+ *nr_types = type + 1;
+
+ return 0;
+}
+
static int hook_load_preprocessor(struct bpf_program *prog)
{
struct perf_probe_event *pev;
@@ -462,7 +571,19 @@ static int hook_load_preprocessor(struct bpf_program *prog)
return -ENOMEM;
}
- err = bpf_program__set_prep(prog, pev->ntevs,
+ priv->type_mapping = malloc(sizeof(int) * pev->ntevs);
+ if (!priv->type_mapping) {
+ pr_debug("No enough memory: alloc type_mapping failed\n");
+ return -ENOMEM;
+ }
+ memset(priv->type_mapping, -1,
+ sizeof(int) * pev->ntevs);
+
+ err = map_prologue(pev, priv->type_mapping, &priv->nr_types);
+ if (err)
+ return err;
+
+ err = bpf_program__set_prep(prog, priv->nr_types,
preproc_gen_prologue);
return err;
}
@@ -596,10 +717,13 @@ int bpf__foreach_tev(struct bpf_object *obj,
for (i = 0; i < pev->ntevs; i++) {
tev = &pev->tevs[i];
- if (priv->need_prologue)
- fd = bpf_program__nth_fd(prog, i);
- else
+ if (priv->need_prologue) {
+ int type = priv->type_mapping[i];
+
+ fd = bpf_program__nth_fd(prog, type);
+ } else {
fd = bpf_program__fd(prog);
+ }
if (fd < 0) {
pr_debug("bpf: failed to get file descriptor\n");
--
2.1.0
^ permalink raw reply related [flat|nested] 21+ messages in thread* [PATCH 14/16] perf test: Print result for each LLVM subtest
2015-11-17 15:31 [GIT PULL 00/16] perf/ebpf improvements and fixes Arnaldo Carvalho de Melo
` (12 preceding siblings ...)
2015-11-17 15:31 ` [PATCH 13/16] perf bpf: Use same BPF program if arguments are identical Arnaldo Carvalho de Melo
@ 2015-11-17 15:31 ` Arnaldo Carvalho de Melo
2015-11-17 15:31 ` [PATCH 15/16] perf test: Print result for each BPF subtest Arnaldo Carvalho de Melo
` (2 subsequent siblings)
16 siblings, 0 replies; 21+ messages in thread
From: Arnaldo Carvalho de Melo @ 2015-11-17 15:31 UTC (permalink / raw)
To: Ingo Molnar
Cc: linux-kernel, Wang Nan, Alexei Starovoitov, Masami Hiramatsu,
Zefan Li, pi3orama, Arnaldo Carvalho de Melo
From: Wang Nan <wangnan0@huawei.com>
Currently 'perf test llvm' and 'perf test BPF' have multiple sub-tests,
but the result is provided in only one line:
# perf test LLVM
35: Test LLVM searching and compiling : Ok
This patch introduces sub-tests support, allowing 'perf test' to report
result for each sub-tests:
# perf test LLVM
35: Test LLVM searching and compiling :
35.1: Basic BPF llvm compiling test : Ok
35.2: Test kbuild searching : Ok
35.3: Compile source for BPF prologue generation test : Ok
When a failure happens:
# cat ~/.perfconfig
[llvm]
clang-path = "/bin/false"
# perf test LLVM
35: Test LLVM searching and compiling :
35.1: Basic BPF llvm compiling test : FAILED!
35.2: Test kbuild searching : Skip
35.3: Compile source for BPF prologue generation test : Skip
And:
# rm ~/.perfconfig
# ./perf test LLVM
35: Test LLVM searching and compiling :
35.1: Basic BPF llvm compiling test : Skip
35.2: Test kbuild searching : Skip
35.3: Compile source for BPF prologue generation test : Skip
Skip by user:
# ./perf test -s 1,`seq -s , 3 42`
1: vmlinux symtab matches kallsyms : Skip (user override)
2: detect openat syscall event : Ok
...
35: Test LLVM searching and compiling : Skip (user override)
...
Suggested-and-Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1447749170-175898-4-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/tests/builtin-test.c | 111 ++++++++++++++++++++++++++++++++--------
tools/perf/tests/llvm.c | 65 +++++++++++------------
tools/perf/tests/tests.h | 22 +++++++-
3 files changed, 141 insertions(+), 57 deletions(-)
diff --git a/tools/perf/tests/builtin-test.c b/tools/perf/tests/builtin-test.c
index 80c442eab767..664c2e894b08 100644
--- a/tools/perf/tests/builtin-test.c
+++ b/tools/perf/tests/builtin-test.c
@@ -159,7 +159,13 @@ static struct test generic_tests[] = {
},
{
.desc = "Test LLVM searching and compiling",
- .func = test__llvm,
+ .need_subtests = true,
+ .subtest = {
+ .skip_if_fail = true,
+ .get_nr = test__llvm_subtest_get_nr,
+ .get_desc = test__llvm_subtest_get_desc,
+ .func = test__llvm_subtest,
+ },
},
{
.desc = "Test topology in session",
@@ -203,7 +209,7 @@ static bool perf_test__matches(struct test *test, int curr, int argc, const char
return false;
}
-static int run_test(struct test *test)
+static int run_test(struct test *test, int subtest)
{
int status, err = -1, child = fork();
char sbuf[STRERR_BUFSIZE];
@@ -216,7 +222,10 @@ static int run_test(struct test *test)
if (!child) {
pr_debug("test child forked, pid %d\n", getpid());
- err = test->func();
+ if (!test->need_subtests)
+ err = test->func();
+ else
+ err = test->subtest.func(subtest);
exit(err);
}
@@ -234,8 +243,48 @@ static int run_test(struct test *test)
}
#define for_each_test(j, t) \
- for (j = 0; j < ARRAY_SIZE(tests); j++) \
- for (t = &tests[j][0]; t->func; t++)
+ for (j = 0; j < ARRAY_SIZE(tests); j++) \
+ for (t = &tests[j][0]; \
+ (!t->need_subtests && t->func) || \
+ (t->need_subtests && \
+ t->subtest.get_nr && \
+ t->subtest.get_desc && \
+ t->subtest.func); \
+ t++)
+
+static int test_and_print(struct test *t, bool force_skip, int subtest)
+{
+ int err;
+
+ if (!force_skip) {
+ pr_debug("\n--- start ---\n");
+ err = run_test(t, subtest);
+ pr_debug("---- end ----\n");
+ } else {
+ pr_debug("\n--- force skipped ---\n");
+ err = TEST_SKIP;
+ }
+
+ if (!t->need_subtests)
+ pr_debug("%s:", t->desc);
+ else
+ pr_debug("%s subtest %d:", t->desc, subtest);
+
+ switch (err) {
+ case TEST_OK:
+ pr_info(" Ok\n");
+ break;
+ case TEST_SKIP:
+ color_fprintf(stderr, PERF_COLOR_YELLOW, " Skip\n");
+ break;
+ case TEST_FAIL:
+ default:
+ color_fprintf(stderr, PERF_COLOR_RED, " FAILED!\n");
+ break;
+ }
+
+ return err;
+}
static int __cmd_test(int argc, const char *argv[], struct intlist *skiplist)
{
@@ -264,21 +313,43 @@ static int __cmd_test(int argc, const char *argv[], struct intlist *skiplist)
continue;
}
- pr_debug("\n--- start ---\n");
- err = run_test(t);
- pr_debug("---- end ----\n%s:", t->desc);
-
- switch (err) {
- case TEST_OK:
- pr_info(" Ok\n");
- break;
- case TEST_SKIP:
- color_fprintf(stderr, PERF_COLOR_YELLOW, " Skip\n");
- break;
- case TEST_FAIL:
- default:
- color_fprintf(stderr, PERF_COLOR_RED, " FAILED!\n");
- break;
+ if (!t->need_subtests) {
+ test_and_print(t, false, -1);
+ } else {
+ int subn = t->subtest.get_nr();
+ /*
+ * minus 2 to align with normal testcases.
+ * For subtest we print additional '.x' in number.
+ * for example:
+ *
+ * 35: Test LLVM searching and compiling :
+ * 35.1: Basic BPF llvm compiling test : Ok
+ */
+ int subw = width > 2 ? width - 2 : width;
+ bool skip = false;
+ int subi;
+
+ if (subn <= 0) {
+ color_fprintf(stderr, PERF_COLOR_YELLOW,
+ " Skip (not compiled in)\n");
+ continue;
+ }
+ pr_info("\n");
+
+ for (subi = 0; subi < subn; subi++) {
+ int len = strlen(t->subtest.get_desc(subi));
+
+ if (subw < len)
+ subw = len;
+ }
+
+ for (subi = 0; subi < subn; subi++) {
+ pr_info("%2d.%1d: %-*s:", i, subi + 1, subw,
+ t->subtest.get_desc(subi));
+ err = test_and_print(t, skip, subi);
+ if (err != TEST_OK && t->subtest.skip_if_fail)
+ skip = true;
+ }
}
}
diff --git a/tools/perf/tests/llvm.c b/tools/perf/tests/llvm.c
index 7f4f7f79ca2f..cebb5933be64 100644
--- a/tools/perf/tests/llvm.c
+++ b/tools/perf/tests/llvm.c
@@ -46,7 +46,7 @@ static struct {
},
[LLVM_TESTCASE_BPF_PROLOGUE] = {
.source = test_llvm__bpf_test_prologue_prog,
- .desc = "Test BPF prologue generation",
+ .desc = "Compile source for BPF prologue generation test",
},
};
@@ -131,44 +131,39 @@ out:
return ret;
}
-int test__llvm(void)
+int test__llvm_subtest(int i)
{
- enum test_llvm__testcase i;
+ int ret;
+ void *obj_buf = NULL;
+ size_t obj_buf_sz = 0;
- for (i = 0; i < __LLVM_TESTCASE_MAX; i++) {
- int ret;
- void *obj_buf = NULL;
- size_t obj_buf_sz = 0;
+ if ((i < 0) || (i >= __LLVM_TESTCASE_MAX))
+ return TEST_FAIL;
- ret = test_llvm__fetch_bpf_obj(&obj_buf, &obj_buf_sz,
- i, false);
+ ret = test_llvm__fetch_bpf_obj(&obj_buf, &obj_buf_sz,
+ i, false);
- if (ret == TEST_OK) {
- ret = test__bpf_parsing(obj_buf, obj_buf_sz);
- if (ret != TEST_OK)
- pr_debug("Failed to parse test case '%s'\n",
- bpf_source_table[i].desc);
- }
- free(obj_buf);
-
- switch (ret) {
- case TEST_SKIP:
- return TEST_SKIP;
- case TEST_OK:
- break;
- default:
- /*
- * Test 0 is the basic LLVM test. If test 0
- * fail, the basic LLVM support not functional
- * so the whole test should fail. If other test
- * case fail, it can be fixed by adjusting
- * config so don't report error.
- */
- if (i == 0)
- return TEST_FAIL;
- else
- return TEST_SKIP;
+ if (ret == TEST_OK) {
+ ret = test__bpf_parsing(obj_buf, obj_buf_sz);
+ if (ret != TEST_OK) {
+ pr_debug("Failed to parse test case '%s'\n",
+ bpf_source_table[i].desc);
}
}
- return TEST_OK;
+ free(obj_buf);
+
+ return ret;
+}
+
+int test__llvm_subtest_get_nr(void)
+{
+ return __LLVM_TESTCASE_MAX;
+}
+
+const char *test__llvm_subtest_get_desc(int i)
+{
+ if ((i < 0) || (i >= __LLVM_TESTCASE_MAX))
+ return NULL;
+
+ return bpf_source_table[i].desc;
}
diff --git a/tools/perf/tests/tests.h b/tools/perf/tests/tests.h
index 3c8734a3abbc..f8f9eb6eaa62 100644
--- a/tools/perf/tests/tests.h
+++ b/tools/perf/tests/tests.h
@@ -1,6 +1,8 @@
#ifndef TESTS_H
#define TESTS_H
+#include <stdbool.h>
+
#define TEST_ASSERT_VAL(text, cond) \
do { \
if (!(cond)) { \
@@ -26,7 +28,19 @@ enum {
struct test {
const char *desc;
- int (*func)(void);
+
+ bool need_subtests;
+
+ union {
+ int (*func)(void);
+
+ struct {
+ bool skip_if_fail;
+ int (*get_nr)(void);
+ const char *(*get_desc)(int i);
+ int (*func)(int i);
+ } subtest;
+ };
};
/* Tests */
@@ -65,7 +79,11 @@ int test__fdarray__filter(void);
int test__fdarray__add(void);
int test__kmod_path__parse(void);
int test__thread_map(void);
-int test__llvm(void);
+
+const char *test__llvm_subtest_get_desc(int i);
+int test__llvm_subtest_get_nr(void);
+int test__llvm_subtest(int i);
+
int test__bpf(void);
int test_session_topology(void);
--
2.1.0
^ permalink raw reply related [flat|nested] 21+ messages in thread* [PATCH 15/16] perf test: Print result for each BPF subtest
2015-11-17 15:31 [GIT PULL 00/16] perf/ebpf improvements and fixes Arnaldo Carvalho de Melo
` (13 preceding siblings ...)
2015-11-17 15:31 ` [PATCH 14/16] perf test: Print result for each LLVM subtest Arnaldo Carvalho de Melo
@ 2015-11-17 15:31 ` Arnaldo Carvalho de Melo
2015-11-17 15:31 ` [PATCH 16/16] perf test: Mute test cases error messages if verbose == 0 Arnaldo Carvalho de Melo
2015-11-18 6:32 ` [GIT PULL 00/16] perf/ebpf improvements and fixes Ingo Molnar
16 siblings, 0 replies; 21+ messages in thread
From: Arnaldo Carvalho de Melo @ 2015-11-17 15:31 UTC (permalink / raw)
To: Ingo Molnar
Cc: linux-kernel, Wang Nan, Alexei Starovoitov, Masami Hiramatsu,
Zefan Li, pi3orama, Arnaldo Carvalho de Melo
From: Wang Nan <wangnan0@huawei.com>
This patch prints each sub-tests results for BPF testcases.
Before:
# ./perf test BPF
37: Test BPF filter : Ok
After:
# ./perf test BPF
37: Test BPF filter :
37.1: Test basic BPF filtering : Ok
37.2: Test BPF prologue generation : Ok
When a failure happens:
# cat ~/.perfconfig
[llvm]
clang-path = "/bin/false"
# ./perf test BPF
37: Test BPF filter :
37.1: Test basic BPF filtering : Skip
37.2: Test BPF prologue generation : Skip
Suggested-and-Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1447749170-175898-5-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/tests/bpf.c | 38 ++++++++++++++++++++++++++++----------
tools/perf/tests/builtin-test.c | 8 +++++++-
tools/perf/tests/tests.h | 5 ++++-
3 files changed, 39 insertions(+), 12 deletions(-)
diff --git a/tools/perf/tests/bpf.c b/tools/perf/tests/bpf.c
index dca3998883ee..8c2262ddbde2 100644
--- a/tools/perf/tests/bpf.c
+++ b/tools/perf/tests/bpf.c
@@ -215,28 +215,46 @@ out:
return ret;
}
-int test__bpf(void)
+int test__bpf_subtest_get_nr(void)
+{
+ return (int)ARRAY_SIZE(bpf_testcase_table);
+}
+
+const char *test__bpf_subtest_get_desc(int i)
+{
+ if (i < 0 || i >= (int)ARRAY_SIZE(bpf_testcase_table))
+ return NULL;
+ return bpf_testcase_table[i].desc;
+}
+
+int test__bpf_subtest(int i)
{
- unsigned int i;
int err;
+ if (i < 0 || i >= (int)ARRAY_SIZE(bpf_testcase_table))
+ return TEST_FAIL;
+
if (geteuid() != 0) {
pr_debug("Only root can run BPF test\n");
return TEST_SKIP;
}
- for (i = 0; i < ARRAY_SIZE(bpf_testcase_table); i++) {
- err = __test__bpf(i);
+ err = __test__bpf(i);
+ return err;
+}
- if (err != TEST_OK)
- return err;
- }
+#else
+int test__bpf_subtest_get_nr(void)
+{
+ return 0;
+}
- return TEST_OK;
+const char *test__bpf_subtest_get_desc(int i __maybe_unused)
+{
+ return NULL;
}
-#else
-int test__bpf(void)
+int test__bpf_subtest(int i __maybe_unused)
{
pr_debug("Skip BPF test because BPF support is not compiled\n");
return TEST_SKIP;
diff --git a/tools/perf/tests/builtin-test.c b/tools/perf/tests/builtin-test.c
index 664c2e894b08..2277e0ba96a9 100644
--- a/tools/perf/tests/builtin-test.c
+++ b/tools/perf/tests/builtin-test.c
@@ -173,7 +173,13 @@ static struct test generic_tests[] = {
},
{
.desc = "Test BPF filter",
- .func = test__bpf,
+ .need_subtests = true,
+ .subtest = {
+ .skip_if_fail = true,
+ .get_nr = test__bpf_subtest_get_nr,
+ .get_desc = test__bpf_subtest_get_desc,
+ .func = test__bpf_subtest,
+ },
},
{
.func = NULL,
diff --git a/tools/perf/tests/tests.h b/tools/perf/tests/tests.h
index f8f9eb6eaa62..2ce66b2c48df 100644
--- a/tools/perf/tests/tests.h
+++ b/tools/perf/tests/tests.h
@@ -84,7 +84,10 @@ const char *test__llvm_subtest_get_desc(int i);
int test__llvm_subtest_get_nr(void);
int test__llvm_subtest(int i);
-int test__bpf(void);
+const char *test__bpf_subtest_get_desc(int i);
+int test__bpf_subtest_get_nr(void);
+int test__bpf_subtest(int i);
+
int test_session_topology(void);
#if defined(__arm__) || defined(__aarch64__)
--
2.1.0
^ permalink raw reply related [flat|nested] 21+ messages in thread* [PATCH 16/16] perf test: Mute test cases error messages if verbose == 0
2015-11-17 15:31 [GIT PULL 00/16] perf/ebpf improvements and fixes Arnaldo Carvalho de Melo
` (14 preceding siblings ...)
2015-11-17 15:31 ` [PATCH 15/16] perf test: Print result for each BPF subtest Arnaldo Carvalho de Melo
@ 2015-11-17 15:31 ` Arnaldo Carvalho de Melo
2015-11-18 6:32 ` [GIT PULL 00/16] perf/ebpf improvements and fixes Ingo Molnar
16 siblings, 0 replies; 21+ messages in thread
From: Arnaldo Carvalho de Melo @ 2015-11-17 15:31 UTC (permalink / raw)
To: Ingo Molnar
Cc: linux-kernel, Wang Nan, Alexei Starovoitov, Masami Hiramatsu,
Zefan Li, pi3orama, Arnaldo Carvalho de Melo
From: Wang Nan <wangnan0@huawei.com>
Sometimes error messages in breaks the pretty output of 'perf test'.
For example:
# mv /lib/modules/4.3.0-rc4+/build/vmlinux{,.bak}
# perf test LLVM BPF
35: Test LLVM searching and compiling :
35.1: Basic BPF llvm compiling test : Ok
35.2: Test kbuild searching : Ok
35.3: Compile source for BPF prologue generation test : Ok
37: Test BPF filter :
37.1: Test basic BPF filtering : Ok
37.2: Test BPF prologue generation :Failed to find the path for kernel: No such file or directory FAILED!
This patch mute test cases thoroughly by redirect their stdout and
stderr to /dev/null when verbose == 0. After applying this patch:
# ./perf test LLVM BPF
35: Test LLVM searching and compiling :
35.1: Basic BPF llvm compiling test : Ok
35.2: Test kbuild searching : Ok
35.3: Compile source for BPF prologue generation test : Ok
37: Test BPF filter :
37.1: Test basic BPF filtering : Ok
37.2: Test BPF prologue generation : FAILED!
# ./perf test -v LLVM BPF
35: Test LLVM searching and compiling :
35.1: Basic BPF llvm compiling test :
--- start ---
test child forked, pid 13183
Kernel build dir is set to /lib/modules/4.3.0-rc4+/build
set env: KBUILD_DIR=/lib/modules/4.3.0-rc4+/build
...
bpf: config 'func=null_lseek file->f_mode offset orig' is ok
Looking at the vmlinux_path (7 entries long)
Failed to find the path for kernel: No such file or directory
bpf_probe: failed to convert perf probe eventsFailed to add events selected by BPF
test child finished with -1
---- end ----
Test BPF filter subtest 1: FAILED!
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1447749170-175898-6-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/tests/builtin-test.c | 15 +++++++++++++++
1 file changed, 15 insertions(+)
diff --git a/tools/perf/tests/builtin-test.c b/tools/perf/tests/builtin-test.c
index 2277e0ba96a9..dd3159f53937 100644
--- a/tools/perf/tests/builtin-test.c
+++ b/tools/perf/tests/builtin-test.c
@@ -227,7 +227,22 @@ static int run_test(struct test *test, int subtest)
}
if (!child) {
+ int nullfd;
+
pr_debug("test child forked, pid %d\n", getpid());
+
+ if (!verbose) {
+ nullfd = open("/dev/null", O_WRONLY);
+ if (nullfd >= 0) {
+ close(STDERR_FILENO);
+ close(STDOUT_FILENO);
+
+ dup2(nullfd, STDOUT_FILENO);
+ dup2(STDOUT_FILENO, STDERR_FILENO);
+ close(nullfd);
+ }
+ }
+
if (!test->need_subtests)
err = test->func();
else
--
2.1.0
^ permalink raw reply related [flat|nested] 21+ messages in thread* Re: [GIT PULL 00/16] perf/ebpf improvements and fixes
2015-11-17 15:31 [GIT PULL 00/16] perf/ebpf improvements and fixes Arnaldo Carvalho de Melo
` (15 preceding siblings ...)
2015-11-17 15:31 ` [PATCH 16/16] perf test: Mute test cases error messages if verbose == 0 Arnaldo Carvalho de Melo
@ 2015-11-18 6:32 ` Ingo Molnar
2015-11-18 12:44 ` Arnaldo Carvalho de Melo
16 siblings, 1 reply; 21+ messages in thread
From: Ingo Molnar @ 2015-11-18 6:32 UTC (permalink / raw)
To: Arnaldo Carvalho de Melo
Cc: linux-kernel, Adrian Hunter, Alexei Starovoitov, Alexey Dobriyan,
Brendan Gregg, Daniel Borkmann, David Ahern, He Kuang, Jiri Olsa,
Jonathan Cameron, Kaixu Xia, Masami Hiramatsu, Namhyung Kim,
Peter Zijlstra, pi3orama, Wang Nan, Zefan Li,
Arnaldo Carvalho de Melo
* Arnaldo Carvalho de Melo <acme@kernel.org> wrote:
> Hi Ingo,
>
> This is on top of my last perf-urgent-for-mingo pull req, that is
> outstanding, please check if this can get into this merge window.
>
> - Arnaldo
>
> The following changes since commit 092b1f0b5f9f797812da0de927c3aa26acbe8762:
>
> perf probe: Clear probe_trace_event when add_probe_trace_event() fails (2015-11-13 12:28:09 -0300)
>
> are available in the git repository at:
>
> git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux.git tags/perf-ebpf-for-mingo
>
> for you to fetch changes up to 0fbcd50e1385d3a78ddb3cf52dcdff802bfb835e:
>
> perf test: Mute test cases error messages if verbose == 0 (2015-11-17 11:45:06 -0300)
>
> ----------------------------------------------------------------
> perf/ebpf improvements and fixes:
>
> User visible:
>
> - Allows BPF scriptlets specify arguments to be fetched using
> DWARF info, using a prologue generated at compile/build time (He Kuang, Wang Nan)
>
> - Allow attaching BPF scriptlets to module symbols (Wang Nan)
>
> - Allow attaching BPF scriptlets to userspace code using uprobe (Wang Nan)
>
> - BPF programs now can specify 'perf probe' tunables via its section name,
> separating key=val values using semicolons (Wang Nan)
>
> Testing some of these new BPF features:
>
> Use case: get callchains when receiving SSL packets, filter then in the
> kernel, at arbitrary place.
>
> # cat ssl.bpf.c
> #define SEC(NAME) __attribute__((section(NAME), used))
>
> struct pt_regs;
>
> SEC("func=__inet_lookup_established hnum")
> int func(struct pt_regs *ctx, int err, unsigned short port)
> {
> return err == 0 && port == 443;
> }
>
> char _license[] SEC("license") = "GPL";
> int _version SEC("version") = LINUX_VERSION_CODE;
> #
> # perf record -a -g -e ssl.bpf.c
> ^C[ perf record: Woken up 1 times to write data ]
> [ perf record: Captured and wrote 0.787 MB perf.data (3 samples) ]
> # perf script | head -30
> swapper 0 [000] 58783.268118: perf_bpf_probe:func: (ffffffff816a0f60) hnum=0x1bb
> 8a0f61 __inet_lookup_established (/lib/modules/4.3.0+/build/vmlinux)
> 896def ip_rcv_finish (/lib/modules/4.3.0+/build/vmlinux)
> 8976c2 ip_rcv (/lib/modules/4.3.0+/build/vmlinux)
> 855eba __netif_receive_skb_core (/lib/modules/4.3.0+/build/vmlinux)
> 8565d8 __netif_receive_skb (/lib/modules/4.3.0+/build/vmlinux)
> 8572a8 process_backlog (/lib/modules/4.3.0+/build/vmlinux)
> 856b11 net_rx_action (/lib/modules/4.3.0+/build/vmlinux)
> 2a284b __do_softirq (/lib/modules/4.3.0+/build/vmlinux)
> 2a2ba3 irq_exit (/lib/modules/4.3.0+/build/vmlinux)
> 96b7a4 do_IRQ (/lib/modules/4.3.0+/build/vmlinux)
> 969807 ret_from_intr (/lib/modules/4.3.0+/build/vmlinux)
> 2dede5 cpu_startup_entry (/lib/modules/4.3.0+/build/vmlinux)
> 95d5bc rest_init (/lib/modules/4.3.0+/build/vmlinux)
> 1163ffa start_kernel ([kernel.vmlinux].init.text)
> 11634d7 x86_64_start_reservations ([kernel.vmlinux].init.text)
> 1163623 x86_64_start_kernel ([kernel.vmlinux].init.text)
>
> qemu-system-x86 9178 [003] 58785.792417: perf_bpf_probe:func: (ffffffff816a0f60) hnum=0x1bb
> 8a0f61 __inet_lookup_established (/lib/modules/4.3.0+/build/vmlinux)
> 896def ip_rcv_finish (/lib/modules/4.3.0+/build/vmlinux)
> 8976c2 ip_rcv (/lib/modules/4.3.0+/build/vmlinux)
> 855eba __netif_receive_skb_core (/lib/modules/4.3.0+/build/vmlinux)
> 8565d8 __netif_receive_skb (/lib/modules/4.3.0+/build/vmlinux)
> 856660 netif_receive_skb_internal (/lib/modules/4.3.0+/build/vmlinux)
> 8566ec netif_receive_skb_sk (/lib/modules/4.3.0+/build/vmlinux)
> 430a br_handle_frame_finish ([bridge])
> 48bc br_handle_frame ([bridge])
> 855f44 __netif_receive_skb_core (/lib/modules/4.3.0+/build/vmlinux)
> 8565d8 __netif_receive_skb (/lib/modules/4.3.0+/build/vmlinux)
> #
>
> Use 'perf probe' various options to list functions, see what variables can
> be collected at any given point, experiment first collecting without a filter,
> then filter, use it together with 'perf trace', 'perf top', with or without
> callchains, if it explodes, please tell us!
>
> Infrastructure:
>
> - Add further 'perf test' entries for BPF and LLVM (Wang Nan)
>
> - Improve 'perf test' to suport subtests, so that the series of tests
> performed in the LLVM and BPF main tests appear in the default 'perf test'
> output (Wang Nan)
>
> - Move memdup() from tools/perf to tools/lib/string.c (Arnaldo Carvalho de Melo)
>
> - Adopt strtobool() from the kernel into tools/lib/ (Wang Nan)
>
> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
>
> ----------------------------------------------------------------
> Arnaldo Carvalho de Melo (1):
> tools: Adopt memdup() from tools/perf, moving it to tools/lib/string.c
>
> He Kuang (1):
> perf bpf: Add prologue for BPF programs for fetching arguments
>
> Wang Nan (14):
> tools: Clone the kernel's strtobool function
> bpf tools: Load a program with different instances using preprocessor
> perf bpf: Add BPF_PROLOGUE config options for further patches
> perf bpf: Compile dwarf-regs.c if CONFIG_BPF_PROLOGUE is on
> perf bpf: Allow BPF program attach to uprobe events
> perf bpf: Allow attaching BPF programs to modules symbols
> perf bpf: Allow BPF program config probing options
> perf bpf: Generate prologue for BPF programs
> perf test: Test the BPF prologue adding infrastructure
> perf test: Fix 'perf test BPF' when it fails to find a suitable vmlinux
> perf bpf: Use same BPF program if arguments are identical
> perf test: Print result for each LLVM subtest
> perf test: Print result for each BPF subtest
> perf test: Mute test cases error messages if verbose == 0
>
> tools/include/linux/string.h | 11 +
> tools/lib/bpf/libbpf.c | 146 ++++++++-
> tools/lib/bpf/libbpf.h | 64 ++++
> tools/lib/string.c | 62 ++++
> tools/perf/MANIFEST | 2 +
> tools/perf/arch/x86/util/Build | 1 +
> tools/perf/config/Makefile | 12 +
> tools/perf/tests/.gitignore | 1 +
> tools/perf/tests/Build | 9 +-
> tools/perf/tests/bpf-script-test-prologue.c | 35 +++
> tools/perf/tests/bpf.c | 79 ++++-
> tools/perf/tests/builtin-test.c | 134 ++++++--
> tools/perf/tests/llvm.c | 67 ++--
> tools/perf/tests/llvm.h | 2 +
> tools/perf/tests/tests.h | 27 +-
> tools/perf/util/Build | 7 +
> tools/perf/util/bpf-loader.c | 434 +++++++++++++++++++++++++-
> tools/perf/util/bpf-loader.h | 4 +
> tools/perf/util/bpf-prologue.c | 455 ++++++++++++++++++++++++++++
> tools/perf/util/bpf-prologue.h | 34 +++
> tools/perf/util/include/linux/string.h | 3 -
> tools/perf/util/probe-event.c | 7 +-
> tools/perf/util/string.c | 16 -
> 23 files changed, 1502 insertions(+), 110 deletions(-)
> create mode 100644 tools/include/linux/string.h
> create mode 100644 tools/lib/string.c
> create mode 100644 tools/perf/tests/bpf-script-test-prologue.c
> create mode 100644 tools/perf/util/bpf-prologue.c
> create mode 100644 tools/perf/util/bpf-prologue.h
> delete mode 100644 tools/perf/util/include/linux/string.h
So considering the relatively large diffstat and the fact that we are 3 days after
the closing of the merge window, I think we should separate this into minimal
fixes for perf/urgent, and more involved changes for v4.5.
Nice progress with eBPF tooling!
Thanks,
Ingo
^ permalink raw reply [flat|nested] 21+ messages in thread* Re: [GIT PULL 00/16] perf/ebpf improvements and fixes
2015-11-18 6:32 ` [GIT PULL 00/16] perf/ebpf improvements and fixes Ingo Molnar
@ 2015-11-18 12:44 ` Arnaldo Carvalho de Melo
2015-11-18 13:06 ` pi3orama
0 siblings, 1 reply; 21+ messages in thread
From: Arnaldo Carvalho de Melo @ 2015-11-18 12:44 UTC (permalink / raw)
To: Ingo Molnar
Cc: linux-kernel, Adrian Hunter, Alexei Starovoitov, Alexey Dobriyan,
Brendan Gregg, Daniel Borkmann, David Ahern, He Kuang, Jiri Olsa,
Jonathan Cameron, Kaixu Xia, Masami Hiramatsu, Namhyung Kim,
Peter Zijlstra, pi3orama, Wang Nan, Zefan Li
Em Wed, Nov 18, 2015 at 07:32:38AM +0100, Ingo Molnar escreveu:
> So considering the relatively large diffstat and the fact that we are 3 days after
> the closing of the merge window, I think we should separate this into minimal
> fixes for perf/urgent, and more involved changes for v4.5.
Ok, I'll do that, separate pure bugfixes into perf/urgent and then move
the rest to perf/core.
> Nice progress with eBPF tooling!
Indeed!
- Arnaldo
^ permalink raw reply [flat|nested] 21+ messages in thread
* Re: [GIT PULL 00/16] perf/ebpf improvements and fixes
2015-11-18 12:44 ` Arnaldo Carvalho de Melo
@ 2015-11-18 13:06 ` pi3orama
2015-11-18 13:27 ` Arnaldo Carvalho de Melo
0 siblings, 1 reply; 21+ messages in thread
From: pi3orama @ 2015-11-18 13:06 UTC (permalink / raw)
To: Arnaldo Carvalho de Melo
Cc: Ingo Molnar, linux-kernel, Adrian Hunter, Alexei Starovoitov,
Alexey Dobriyan, Brendan Gregg, Daniel Borkmann, David Ahern,
He Kuang, Jiri Olsa, Jonathan Cameron, Kaixu Xia,
Masami Hiramatsu, Namhyung Kim, Peter Zijlstra, Wang Nan,
Zefan Li
发自我的 iPhone
> 在 2015年11月18日，下午8:44，Arnaldo Carvalho de Melo <acme@kernel.org> 写道：
>
> Em Wed, Nov 18, 2015 at 07:32:38AM +0100, Ingo Molnar escreveu:
>> So considering the relatively large diffstat and the fact that we are 3 days after
>> the closing of the merge window, I think we should separate this into minimal
>> fixes for perf/urgent, and more involved changes for v4.5.
>
> Ok, I'll do that, separate pure bugfixes into perf/urgent and then move
> the rest to perf/core.
So you won't maintain perf/ebpf and will move all eBPF related commits to
perf/core? Then let me wait for your action, and rebase my local tree to perf/core
again.
I hope I can start sending other patches in my local tree to you soon. They are
almost ready.
Thank you.
>
>> Nice progress with eBPF tooling!
>
> Indeed!
>
> - Arnaldo
^ permalink raw reply [flat|nested] 21+ messages in thread
* Re: [GIT PULL 00/16] perf/ebpf improvements and fixes
2015-11-18 13:06 ` pi3orama
@ 2015-11-18 13:27 ` Arnaldo Carvalho de Melo
0 siblings, 0 replies; 21+ messages in thread
From: Arnaldo Carvalho de Melo @ 2015-11-18 13:27 UTC (permalink / raw)
To: pi3orama
Cc: Ingo Molnar, linux-kernel, Adrian Hunter, Alexei Starovoitov,
Alexey Dobriyan, Brendan Gregg, Daniel Borkmann, David Ahern,
He Kuang, Jiri Olsa, Jonathan Cameron, Kaixu Xia,
Masami Hiramatsu, Namhyung Kim, Peter Zijlstra, Wang Nan,
Zefan Li
Em Wed, Nov 18, 2015 at 09:06:58PM +0800, pi3orama escreveu:
>
>
> 发自我的 iPhone
>
> > 在 2015年11月18日，下午8:44，Arnaldo Carvalho de Melo <acme@kernel.org> 写道：
> >
> > Em Wed, Nov 18, 2015 at 07:32:38AM +0100, Ingo Molnar escreveu:
> >> So considering the relatively large diffstat and the fact that we are 3 days after
> >> the closing of the merge window, I think we should separate this into minimal
> >> fixes for perf/urgent, and more involved changes for v4.5.
> >
> > Ok, I'll do that, separate pure bugfixes into perf/urgent and then move
> > the rest to perf/core.
>
> So you won't maintain perf/ebpf and will move all eBPF related commits to
> perf/core? Then let me wait for your action, and rebase my local tree to perf/core
> again.
I think you can work on perf/ebpf, I can't envision any major problems
arising from that, what I'll do is basically cherry-pick pure fixes that
are there, IIRC there are several (like the perf test emitting errors in
non verbose mode, etc), and then rebase perf/ebpf on top of that, just
some patch reordering should take place.
At that point I'll just rename perf/ebpf to perf/core and collect more
non-pure-bug-fixes on top of it.
> I hope I can start sending other patches in my local tree to you soon. They are
> almost ready.
Ok
> Thank you.
> >
> >> Nice progress with eBPF tooling!
> >
> > Indeed!
> >
> > - Arnaldo
^ permalink raw reply [flat|nested] 21+ messages in thread