Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1231364 > unrolled thread

[GIT PULL 00/22] perf tools: filtering events using eBPF programs

Started byWang Nan <wangnan0@huawei.com>
First post2015-09-23 13:30 +0200
Last post2015-09-23 15:50 +0200
Articles 7 — 2 participants

Back to article view | Back to linux.kernel

Contents

  [GIT PULL 00/22] perf tools: filtering events using eBPF programs Wang Nan <wangnan0@huawei.com> - 2015-09-23 13:30 +0200
    [PATCH 12/22] bpf tools: Load a program with different instances using preprocessor Wang Nan <wangnan0@huawei.com> - 2015-09-23 13:30 +0200
    [PATCH 09/22] perf test: Enforce LLVM test for BPF test Wang Nan <wangnan0@huawei.com> - 2015-09-23 13:30 +0200
    [PATCH 18/22] perf record: Support custom vmlinux path Wang Nan <wangnan0@huawei.com> - 2015-09-23 13:30 +0200
    [PATCH 20/22] perf test: Enforce LLVM test, add kbuild test Wang Nan <wangnan0@huawei.com> - 2015-09-23 13:30 +0200
    [PATCH 22/22] perf probe: Fix module probing with shortname Wang Nan <wangnan0@huawei.com> - 2015-09-23 13:30 +0200
    Re: [GIT PULL 00/22] perf tools: filtering events using eBPF programs Arnaldo Carvalho de Melo <acme@redhat.com> - 2015-09-23 15:50 +0200

#1231364 — [GIT PULL 00/22] perf tools: filtering events using eBPF programs

FromWang Nan <wangnan0@huawei.com>
Date2015-09-23 13:30 +0200
Subject[GIT PULL 00/22] perf tools: filtering events using eBPF programs
Message-ID<qbQpj-2GS-3@gated-at.bofh.it>
Hi Arnaldo,

   I hope you would be satisified with this weeks pull request. In this
patchset, we totally get rid of dummy events by utilizing Namhyung's newest
perf probing API.

Patch 1-6 are different from previous patchset. Plase have a look.

Due to some reason I can't access my kernel.org account in my company today,
so I reuse my github repository. I'll update my kernel.org tree at home.

I'll have a long vacation from Sept. 24. I hope I can discuss with you with
my private email. However, It seems impossible to modify code and test until
Oct. 7. If you find some small problem, could you please help me fix them?

Thank you.

The following changes since commit 5933944f697c15d6f1fb16dc22c02aac9d2ec206:

  perf tools: Make perf depend on libbpf (2015-09-22 10:17:01 -0300)

are available in the git repository at:

  https://github.com/WangNan0/linux.git tags/perf-ebpf-for-acme-20150923

for you to fetch changes up to 1465cf7b201b8b21c61fa54ffe15094f66e73ab0:

  perf probe: Fix module probing with shortname (2015-09-23 10:44:58 +0000)

----------------------------------------------------------------
Get rid of dummy events by utilizing new perf probe API.

Signed-off-by: Wang Nan <wangnan0@huawei.com>

----------------------------------------------------------------
He Kuang (2):
      perf tools: Add prologue for BPF programs for fetching arguments
      perf record: Support custom vmlinux path

Wang Nan (20):
      perf ebpf: Add the libbpf glue
      perf tools: Enable passing bpf object file to --event
      perf record, bpf: Create probe points for BPF programs
      perf record: Load eBPF object into kernel
      perf tools: Collect perf_evsel in BPF object files
      perf tools: Attach eBPF program to perf event
      perf record: Add clang options for compiling BPF scripts
      perf tools: Compile scriptlets to BPF objects when passing '.c' to --event
      perf test: Enforce LLVM test for BPF test
      perf test: Add 'perf test BPF'
      perf probe: Reset args and nargs for probe_trace_event when failure
      bpf tools: Load a program with different instances using preprocessor
      perf tools: Add BPF_PROLOGUE config options for further patches
      perf tools: Compile dwarf-regs.c if CONFIG_BPF_PROLOGUE is on
      perf tools: Generate prologue for BPF programs
      perf tools: Use same BPF program if arguments are identical
      perf tools: Allow BPF program attach to uprobe events
      perf test: Enforce LLVM test, add kbuild test
      perf test: Test BPF prologue
      perf probe: Fix module probing with shortname

 tools/lib/bpf/libbpf.c                      | 143 +++++-
 tools/lib/bpf/libbpf.h                      |  22 +
 tools/perf/arch/x86/util/Build              |   1 +
 tools/perf/builtin-record.c                 |  11 +
 tools/perf/config/Makefile                  |  12 +
 tools/perf/perf.c                           |   2 +
 tools/perf/tests/Build                      |  24 +-
 tools/perf/tests/bpf-script-example.c       |  48 ++
 tools/perf/tests/bpf-script-test-kbuild.c   |  21 +
 tools/perf/tests/bpf-script-test-prologue.c |  35 ++
 tools/perf/tests/bpf.c                      | 227 ++++++++++
 tools/perf/tests/builtin-test.c             |  12 +
 tools/perf/tests/llvm.c                     | 210 ++++++++-
 tools/perf/tests/llvm.h                     |  29 ++
 tools/perf/tests/tests.h                    |   3 +
 tools/perf/util/Build                       |   2 +
 tools/perf/util/bpf-loader.c                | 676 ++++++++++++++++++++++++++++
 tools/perf/util/bpf-loader.h                |  95 ++++
 tools/perf/util/bpf-prologue.c              | 443 ++++++++++++++++++
 tools/perf/util/bpf-prologue.h              |  34 ++
 tools/perf/util/evsel.c                     |  17 +
 tools/perf/util/evsel.h                     |   1 +
 tools/perf/util/parse-events.c              | 115 +++++
 tools/perf/util/parse-events.h              |   9 +
 tools/perf/util/parse-events.l              |   6 +
 tools/perf/util/parse-events.y              |  29 +-
 tools/perf/util/probe-event.c               |   2 +-
 tools/perf/util/probe-finder.c              |   4 +
 28 files changed, 2202 insertions(+), 31 deletions(-)
 create mode 100644 tools/perf/tests/bpf-script-example.c
 create mode 100644 tools/perf/tests/bpf-script-test-kbuild.c
 create mode 100644 tools/perf/tests/bpf-script-test-prologue.c
 create mode 100644 tools/perf/tests/bpf.c
 create mode 100644 tools/perf/tests/llvm.h
 create mode 100644 tools/perf/util/bpf-loader.c
 create mode 100644 tools/perf/util/bpf-loader.h
 create mode 100644 tools/perf/util/bpf-prologue.c
 create mode 100644 tools/perf/util/bpf-prologue.h
-- 
1.8.3.4

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[toc] | [next] | [standalone]

#1231365 — [PATCH 12/22] bpf tools: Load a program with different instances using preprocessor

FromWang Nan <wangnan0@huawei.com>
Date2015-09-23 13:30 +0200
Subject[PATCH 12/22] bpf tools: Load a program with different instances using preprocessor
Message-ID<qbQpl-2GS-51@gated-at.bofh.it>
In reply to#1231364
In this patch, caller of libbpf is able to control the loaded programs
by installing a preprocessor callback for a BPF program. With
preprocessor, different instances can be created from one BPF program.

This patch will be used by perf to generate different prologue for
different 'struct probe_trace_event' instances matched by one
'struct perf_probe_event'.

bpf_program__set_prep() is added to support this feature. Caller
should pass libbpf the number of instances should be created and a
preprocessor function which will be called when doing real loading.
The callback should return instructions arrays for each instances.

fd field in bpf_programs is replaced by instance, which has an nr field
and fds array. bpf_program__nth_fd() is introduced for read fd of
instances. Old interface bpf_program__fd() is reimplemented by
returning the first fd.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Signed-off-by: He Kuang <hekuang@huawei.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
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: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Link: http://lkml.kernel.org/n/ebpf-6yw9eg0ej3l4jnqhinngkw86@git.kernel.org
---
 tools/lib/bpf/libbpf.c | 143 +++++++++++++++++++++++++++++++++++++++++++++----
 tools/lib/bpf/libbpf.h |  22 ++++++++
 2 files changed, 156 insertions(+), 9 deletions(-)

diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 4252fc2..6a07b26 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -98,7 +98,11 @@ struct bpf_program {
 	} *reloc_desc;
 	int nr_reloc;
 
-	int fd;
+	struct {
+		int nr;
+		int *fds;
+	} instance;
+	bpf_program_prep_t preprocessor;
 
 	struct bpf_object *obj;
 	void *priv;
@@ -152,10 +156,24 @@ 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 is never loaded,
+	 * it is possible that prog->instance.nr == -1.
+	 */
+	if (prog->instance.nr > 0) {
+		for (i = 0; i < prog->instance.nr; i++)
+			zclose(prog->instance.fds[i]);
+	} else if (prog->instance.nr != -1)
+		pr_warning("Internal error: instance.nr is %d\n",
+			   prog->instance.nr);
+
+	prog->instance.nr = -1;
+	zfree(&prog->instance.fds);
 }
 
 static void bpf_program__exit(struct bpf_program *prog)
@@ -206,7 +224,8 @@ 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->instance.fds = NULL;
+	prog->instance.nr = -1;
 
 	return 0;
 errout:
@@ -795,13 +814,71 @@ static int
 bpf_program__load(struct bpf_program *prog,
 		  char *license, u32 kern_version)
 {
-	int err, fd;
+	int err = 0, fd, i;
+
+	if (prog->instance.nr < 0 || !prog->instance.fds) {
+		if (prog->preprocessor) {
+			pr_warning("Internal error: can't load program '%s'\n",
+				   prog->section_name);
+			return -EINVAL;
+		}
+
+		prog->instance.fds = malloc(sizeof(int));
+		if (!prog->instance.fds) {
+			pr_warning("No enough memory for fds\n");
+			return -ENOMEM;
+		}
+		prog->instance.nr = 1;
+		prog->instance.fds[0] = -1;
+	}
+
+	if (!prog->preprocessor) {
+		if (prog->instance.nr != 1)
+			pr_warning("Program '%s' inconsistent: nr(%d) not 1\n",
+				   prog->section_name, prog->instance.nr);
 
-	err = load_program(prog->insns, prog->insns_cnt,
-			   license, kern_version, &fd);
-	if (!err)
-		prog->fd = fd;
+		err = load_program(prog->insns, prog->insns_cnt,
+				   license, kern_version, &fd);
+		if (!err)
+			prog->instance.fds[0] = fd;
+		goto out;
+	}
+
+	for (i = 0; i < prog->instance.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 %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 %dth instance of program '%s'\n",
+					i, prog->section_name);
+			prog->instance.fds[i] = -1;
+			continue;
+		}
+
+		err = load_program(result.new_insn_ptr,
+				   result.new_insn_cnt,
+				   license, kern_version, &fd);
+
+		if (err) {
+			pr_warning("Loading %dth instance of program '%s' failed\n",
+					i, prog->section_name);
+			goto out;
+		}
 
+		if (result.pfd)
+			*result.pfd = fd;
+		prog->instance.fds[i] = fd;
+	}
+out:
 	if (err)
 		pr_warning("failed to load program '%s'\n",
 			   prog->section_name);
@@ -1052,5 +1129,53 @@ const char *bpf_program__title(struct bpf_program *prog, bool dup)
 
 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_instance,
+			  bpf_program_prep_t prep)
+{
+	int *instance_fds;
+
+	if (nr_instance <= 0 || !prep)
+		return -EINVAL;
+
+	if (prog->instance.nr > 0 || prog->instance.fds) {
+		pr_warning("Can't set pre-processor after loading\n");
+		return -EINVAL;
+	}
+
+	instance_fds = malloc(sizeof(int) * nr_instance);
+	if (!instance_fds) {
+		pr_warning("alloc memory failed for instance of fds\n");
+		return -ENOMEM;
+	}
+
+	/* fill all fd with -1 */
+	memset(instance_fds, 0xff, sizeof(int) * nr_instance);
+
+	prog->instance.nr = nr_instance;
+	prog->instance.fds = instance_fds;
+	prog->preprocessor = prep;
+	return 0;
+}
+
+int bpf_program__nth_fd(struct bpf_program *prog, int n)
+{
+	int fd;
+
+	if (n >= prog->instance.nr || n < 0) {
+		pr_warning("Can't get the %dth fd from program %s: only %d instances\n",
+			   n, prog->section_name, prog->instance.nr);
+		return -EINVAL;
+	}
+
+	fd = prog->instance.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 f16170c..d82b89e 100644
--- a/tools/lib/bpf/libbpf.h
+++ b/tools/lib/bpf/libbpf.h
@@ -67,6 +67,28 @@ const char *bpf_program__title(struct bpf_program *prog, bool dup);
 
 int bpf_program__fd(struct bpf_program *prog);
 
+struct bpf_insn;
+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;
+};
+
+typedef int (*bpf_program_prep_t)(struct bpf_program *, int n,
+				  struct bpf_insn *, int insn_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.
-- 
1.8.3.4

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[toc] | [prev] | [next] | [standalone]

#1231366 — [PATCH 09/22] perf test: Enforce LLVM test for BPF test

FromWang Nan <wangnan0@huawei.com>
Date2015-09-23 13:30 +0200
Subject[PATCH 09/22] perf test: Enforce LLVM test for BPF test
Message-ID<qbQpk-2GS-27@gated-at.bofh.it>
In reply to#1231364
This patch replaces the original toy BPF program with previous introduced
bpf-script-example.c. Dynamically embedded it into 'llvm-src.c'.

The newly introduced BPF program attaches a BPF program at
'sys_epoll_pwait()', and collect half samples from it. perf itself never
use that syscall, so further test can verify their result with it.

Since BPF program require LINUX_VERSION_CODE of runtime kernel, this
patch computes that code from uname.

Since the resuling BPF object is useful for further testcases, this patch
introduces 'prepare' and 'cleanup' method to tests, and makes test__llvm()
create a MAP_SHARED memory array to hold the resulting object.

Signed-off-by: He Kuang <hekuang@huawei.com>
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David Ahern <dsahern@gmail.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/n/ebpf-6yw9eg0ej3l4jnqhinngkw86@git.kernel.org
---
 tools/perf/tests/Build          |   9 +++-
 tools/perf/tests/builtin-test.c |   8 ++++
 tools/perf/tests/llvm.c         | 104 +++++++++++++++++++++++++++++++++++-----
 tools/perf/tests/llvm.h         |  14 ++++++
 tools/perf/tests/tests.h        |   2 +
 5 files changed, 123 insertions(+), 14 deletions(-)
 create mode 100644 tools/perf/tests/llvm.h

diff --git a/tools/perf/tests/Build b/tools/perf/tests/Build
index c6f198ae..e80f787 100644
--- a/tools/perf/tests/Build
+++ b/tools/perf/tests/Build
@@ -32,9 +32,16 @@ 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
+perf-y += llvm.o llvm-src.o
 perf-y += topology.o
 
+$(OUTPUT)tests/llvm-src.c: tests/bpf-script-example.c
+	$(call rule_mkdir)
+	$(Q)echo '#include <tests/llvm.h>' > $@
+	$(Q)echo 'const char test_llvm__bpf_prog[] =' >> $@
+	$(Q)sed -e 's/"/\\"/g' -e 's/\(.*\)/"\1\\n"/g' $< >> $@
+	$(Q)echo ';' >> $@
+
 perf-$(CONFIG_X86) += perf-time-to-tsc.o
 ifdef CONFIG_AUXTRACE
 perf-$(CONFIG_X86) += insn-x86.o
diff --git a/tools/perf/tests/builtin-test.c b/tools/perf/tests/builtin-test.c
index d9bf51d..09f3eb8 100644
--- a/tools/perf/tests/builtin-test.c
+++ b/tools/perf/tests/builtin-test.c
@@ -17,6 +17,8 @@
 static struct test {
 	const char *desc;
 	int (*func)(void);
+	void (*prepare)(void);
+	void (*cleanup)(void);
 } tests[] = {
 	{
 		.desc = "vmlinux symtab matches kallsyms",
@@ -177,6 +179,8 @@ static struct test {
 	{
 		.desc = "Test LLVM searching and compiling",
 		.func = test__llvm,
+		.prepare = test__llvm_prepare,
+		.cleanup = test__llvm_cleanup,
 	},
 #ifdef HAVE_AUXTRACE_SUPPORT
 #if defined(__x86_64__) || defined(__i386__)
@@ -278,7 +282,11 @@ static int __cmd_test(int argc, const char *argv[], struct intlist *skiplist)
 		}
 
 		pr_debug("\n--- start ---\n");
+		if (t->prepare)
+			t->prepare();
 		err = run_test(t);
+		if (t->cleanup)
+			t->cleanup();
 		pr_debug("---- end ----\n%s:", t->desc);
 
 		switch (err) {
diff --git a/tools/perf/tests/llvm.c b/tools/perf/tests/llvm.c
index 52d5597..236bf39 100644
--- a/tools/perf/tests/llvm.c
+++ b/tools/perf/tests/llvm.c
@@ -1,9 +1,13 @@
 #include <stdio.h>
+#include <sys/utsname.h>
 #include <bpf/libbpf.h>
 #include <util/llvm-utils.h>
 #include <util/cache.h>
+#include <util/util.h>
+#include <sys/mman.h>
 #include "tests.h"
 #include "debug.h"
+#include "llvm.h"
 
 static int perf_config_cb(const char *var, const char *val,
 			  void *arg __maybe_unused)
@@ -11,16 +15,6 @@ static int perf_config_cb(const char *var, const char *val,
 	return perf_default_config(var, val, arg);
 }
 
-/*
- * Randomly give it a "version" section since we don't really load it
- * into kernel
- */
-static const char test_bpf_prog[] =
-	"__attribute__((section(\"do_fork\"), used)) "
-	"int fork(void *ctx) {return 0;} "
-	"char _license[] __attribute__((section(\"license\"), used)) = \"GPL\";"
-	"int _version __attribute__((section(\"version\"), used)) = 0x40100;";
-
 #ifdef HAVE_LIBBPF_SUPPORT
 static int test__bpf_parsing(void *obj_buf, size_t obj_buf_sz)
 {
@@ -41,12 +35,44 @@ static int test__bpf_parsing(void *obj_buf __maybe_unused,
 }
 #endif
 
+static char *
+compose_source(void)
+{
+	struct utsname utsname;
+	int version, patchlevel, sublevel, err;
+	unsigned long version_code;
+	char *code;
+
+	if (uname(&utsname))
+		return NULL;
+
+	err = sscanf(utsname.release, "%d.%d.%d",
+		     &version, &patchlevel, &sublevel);
+	if (err != 3) {
+		fprintf(stderr, " (Can't get kernel version from uname '%s')",
+			utsname.release);
+		return NULL;
+	}
+
+	version_code = (version << 16) + (patchlevel << 8) + sublevel;
+	err = asprintf(&code, "#define LINUX_VERSION_CODE 0x%08lx;\n%s",
+		       version_code, test_llvm__bpf_prog);
+	if (err < 0)
+		return NULL;
+
+	return code;
+}
+
+#define SHARED_BUF_INIT_SIZE	(1 << 20)
+struct test_llvm__bpf_result *p_test_llvm__bpf_result;
+
 int test__llvm(void)
 {
 	char *tmpl_new, *clang_opt_new;
 	void *obj_buf;
 	size_t obj_buf_sz;
 	int err, old_verbose;
+	char *source;
 
 	perf_config(perf_config_cb, NULL);
 
@@ -73,10 +99,22 @@ int test__llvm(void)
 	if (!llvm_param.clang_opt)
 		llvm_param.clang_opt = strdup("");
 
-	err = asprintf(&tmpl_new, "echo '%s' | %s", test_bpf_prog,
-		       llvm_param.clang_bpf_cmd_template);
-	if (err < 0)
+	source = compose_source();
+	if (!source) {
+		pr_err("Failed to compose source code\n");
+		return -1;
+	}
+
+	/* Quote __EOF__ so strings in source won't be expanded by shell */
+	err = asprintf(&tmpl_new, "cat << '__EOF__' | %s\n%s\n__EOF__\n",
+		       llvm_param.clang_bpf_cmd_template, source);
+	free(source);
+	source = NULL;
+	if (err < 0) {
+		pr_err("Failed to alloc new template\n");
 		return -1;
+	}
+
 	err = asprintf(&clang_opt_new, "-xc %s", llvm_param.clang_opt);
 	if (err < 0)
 		return -1;
@@ -93,6 +131,46 @@ int test__llvm(void)
 	}
 
 	err = test__bpf_parsing(obj_buf, obj_buf_sz);
+	if (!err && p_test_llvm__bpf_result) {
+		if (obj_buf_sz > SHARED_BUF_INIT_SIZE) {
+			pr_err("Resulting object too large\n");
+		} else {
+			p_test_llvm__bpf_result->size = obj_buf_sz;
+			memcpy(p_test_llvm__bpf_result->object,
+			       obj_buf, obj_buf_sz);
+		}
+	}
 	free(obj_buf);
 	return err;
 }
+
+void test__llvm_prepare(void)
+{
+	p_test_llvm__bpf_result = mmap(NULL, SHARED_BUF_INIT_SIZE,
+				       PROT_READ | PROT_WRITE,
+				       MAP_SHARED | MAP_ANONYMOUS, -1, 0);
+	if (!p_test_llvm__bpf_result)
+		return;
+	memset((void *)p_test_llvm__bpf_result, '\0', SHARED_BUF_INIT_SIZE);
+}
+
+void test__llvm_cleanup(void)
+{
+	unsigned long boundary, buf_end;
+
+	if (!p_test_llvm__bpf_result)
+		return;
+	if (p_test_llvm__bpf_result->size == 0) {
+		munmap((void *)p_test_llvm__bpf_result, SHARED_BUF_INIT_SIZE);
+		p_test_llvm__bpf_result = NULL;
+		return;
+	}
+
+	buf_end = (unsigned long)p_test_llvm__bpf_result + SHARED_BUF_INIT_SIZE;
+
+	boundary = (unsigned long)(p_test_llvm__bpf_result);
+	boundary += p_test_llvm__bpf_result->size;
+	boundary = (boundary + (page_size - 1)) &
+			(~((unsigned long)page_size - 1));
+	munmap((void *)boundary, buf_end - boundary);
+}
diff --git a/tools/perf/tests/llvm.h b/tools/perf/tests/llvm.h
new file mode 100644
index 0000000..1e89e46
--- /dev/null
+++ b/tools/perf/tests/llvm.h
@@ -0,0 +1,14 @@
+#ifndef PERF_TEST_LLVM_H
+#define PERF_TEST_LLVM_H
+
+#include <stddef.h> /* for size_t */
+
+struct test_llvm__bpf_result {
+	size_t size;
+	char object[];
+};
+
+extern struct test_llvm__bpf_result *p_test_llvm__bpf_result;
+extern const char test_llvm__bpf_prog[];
+
+#endif
diff --git a/tools/perf/tests/tests.h b/tools/perf/tests/tests.h
index 0b35496..a5e6f641 100644
--- a/tools/perf/tests/tests.h
+++ b/tools/perf/tests/tests.h
@@ -63,6 +63,8 @@ int test__fdarray__add(void);
 int test__kmod_path__parse(void);
 int test__thread_map(void);
 int test__llvm(void);
+void test__llvm_prepare(void);
+void test__llvm_cleanup(void);
 int test__insn_x86(void);
 int test_session_topology(void);
 
-- 
1.8.3.4

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[toc] | [prev] | [next] | [standalone]

#1231367 — [PATCH 18/22] perf record: Support custom vmlinux path

FromWang Nan <wangnan0@huawei.com>
Date2015-09-23 13:30 +0200
Subject[PATCH 18/22] perf record: Support custom vmlinux path
Message-ID<qbQpl-2GS-53@gated-at.bofh.it>
In reply to#1231364
From: He Kuang <hekuang@huawei.com>

Make perf-record command support --vmlinux option if BPF_PROLOGUE is on.

'perf record' needs vmlinux as the source of DWARF info to generate
prologue for BPF programs, so path of vmlinux should be specified.

Short name 'k' has been taken by 'clockid'. This patch skips the short
option name and use '--vmlinux' for vmlinux path.

Signed-off-by: He Kuang <hekuang@huawei.com>
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
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: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Link: http://lkml.kernel.org/n/ebpf-6yw9eg0ej3l4jnqhinngkw86@git.kernel.org
---
 tools/perf/builtin-record.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index ea3eef6..a0c8ef8 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -1102,6 +1102,10 @@ struct option __record_options[] = {
 		   "clang binary to use for compiling BPF scriptlets"),
 	OPT_STRING(0, "clang-opt", &llvm_param.clang_opt, "clang options",
 		   "options passed to clang when compiling BPF scriptlets"),
+#ifdef HAVE_BPF_PROLOGUE
+	OPT_STRING(0, "vmlinux", &symbol_conf.vmlinux_name,
+		   "file", "vmlinux pathname"),
+#endif
 #endif
 	OPT_END()
 };
-- 
1.8.3.4

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[toc] | [prev] | [next] | [standalone]

#1231368 — [PATCH 20/22] perf test: Enforce LLVM test, add kbuild test

FromWang Nan <wangnan0@huawei.com>
Date2015-09-23 13:30 +0200
Subject[PATCH 20/22] perf test: Enforce LLVM test, add kbuild test
Message-ID<qbQpm-2GS-55@gated-at.bofh.it>
In reply to#1231364
This patch enforces existing LLVM test, makes it compile more than one
BPF source file. The compiled results are stored, can be used for other
testcases. Except the first testcase (named LLVM_TESTCASE_BASE), failures
of other test cases are not considered as failure of the whole test.

Adds a kbuild testcase to check whether kernel headers can be correctly
found.

For example:

 # perf test LLVM

   38: Test LLVM searching and compiling                        : (llvm.kbuild-dir can be fixed) Ok

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
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/n/ebpf-6yw9eg0ej3l4jnqhinngkw86@git.kernel.org
---
 tools/perf/tests/Build                    |  11 ++-
 tools/perf/tests/bpf-script-example.c     |   4 +
 tools/perf/tests/bpf-script-test-kbuild.c |  21 ++++
 tools/perf/tests/bpf.c                    |   3 +-
 tools/perf/tests/llvm.c                   | 154 ++++++++++++++++++++++--------
 tools/perf/tests/llvm.h                   |  10 +-
 6 files changed, 156 insertions(+), 47 deletions(-)
 create mode 100644 tools/perf/tests/bpf-script-test-kbuild.c

diff --git a/tools/perf/tests/Build b/tools/perf/tests/Build
index 5cfb420..2bd5f37 100644
--- a/tools/perf/tests/Build
+++ b/tools/perf/tests/Build
@@ -32,17 +32,24 @@ 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.o
+perf-y += llvm.o llvm-src-base.o llvm-src-kbuild.o
 perf-y += bpf.o
 perf-y += topology.o
 
-$(OUTPUT)tests/llvm-src.c: tests/bpf-script-example.c
+$(OUTPUT)tests/llvm-src-base.c: tests/bpf-script-example.c
 	$(call rule_mkdir)
 	$(Q)echo '#include <tests/llvm.h>' > $@
 	$(Q)echo 'const char test_llvm__bpf_prog[] =' >> $@
 	$(Q)sed -e 's/"/\\"/g' -e 's/\(.*\)/"\1\\n"/g' $< >> $@
 	$(Q)echo ';' >> $@
 
+$(OUTPUT)tests/llvm-src-kbuild.c: tests/bpf-script-test-kbuild.c
+	$(call rule_mkdir)
+	$(Q)echo '#include <tests/llvm.h>' > $@
+	$(Q)echo 'const char test_llvm__bpf_test_kbuild_prog[] =' >> $@
+	$(Q)sed -e 's/"/\\"/g' -e 's/\(.*\)/"\1\\n"/g' $< >> $@
+	$(Q)echo ';' >> $@
+
 perf-$(CONFIG_X86) += perf-time-to-tsc.o
 ifdef CONFIG_AUXTRACE
 perf-$(CONFIG_X86) += insn-x86.o
diff --git a/tools/perf/tests/bpf-script-example.c b/tools/perf/tests/bpf-script-example.c
index 410a70b..0ec9c2c 100644
--- a/tools/perf/tests/bpf-script-example.c
+++ b/tools/perf/tests/bpf-script-example.c
@@ -1,3 +1,7 @@
+/*
+ * bpf-script-example.c
+ * Test basic LLVM building
+ */
 #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'
diff --git a/tools/perf/tests/bpf-script-test-kbuild.c b/tools/perf/tests/bpf-script-test-kbuild.c
new file mode 100644
index 0000000..a11f589
--- /dev/null
+++ b/tools/perf/tests/bpf-script-test-kbuild.c
@@ -0,0 +1,21 @@
+/*
+ * bpf-script-test-kbuild.c
+ * Test include from kernel header
+ */
+#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>
+#include <uapi/asm/ptrace.h>
+
+SEC("func=vfs_llseek")
+int bpf_func__vfs_llseek(struct pt_regs *ctx)
+{
+	return 0;
+}
+
+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 d7cdc84..4dd701b 100644
--- a/tools/perf/tests/bpf.c
+++ b/tools/perf/tests/bpf.c
@@ -140,7 +140,8 @@ int test__bpf(void)
 		return TEST_SKIP;
 	}
 
-	test_llvm__fetch_bpf_obj(&obj_buf, &obj_buf_sz);
+	test_llvm__fetch_bpf_obj(&obj_buf, &obj_buf_sz, LLVM_TESTCASE_BASE);
+
 	if (!obj_buf || !obj_buf_sz) {
 		if (verbose == 0)
 			fprintf(stderr, " (fix 'perf test LLVM' first)");
diff --git a/tools/perf/tests/llvm.c b/tools/perf/tests/llvm.c
index fd5fdb0..75cd99f 100644
--- a/tools/perf/tests/llvm.c
+++ b/tools/perf/tests/llvm.c
@@ -9,6 +9,22 @@
 #include "debug.h"
 #include "llvm.h"
 
+#define SHARED_BUF_INIT_SIZE	(1 << 20)
+struct llvm_testcase {
+	const char *source;
+	const char *errmsg;
+	struct test_llvm__bpf_result *result;
+	bool tried;
+} llvm_testcases[NR_LLVM_TESTCASES + 1] = {
+	[LLVM_TESTCASE_BASE]	= {.source = test_llvm__bpf_prog,
+				   .errmsg = "Basic LLVM compiling failed",
+				   .tried = false},
+	[LLVM_TESTCASE_KBUILD]	= {.source = test_llvm__bpf_test_kbuild_prog,
+				   .errmsg = "llvm.kbuild-dir can be fixed",
+				   .tried = false},
+	{.source = NULL}
+};
+
 static int perf_config_cb(const char *var, const char *val,
 			  void *arg __maybe_unused)
 {
@@ -36,7 +52,7 @@ static int test__bpf_parsing(void *obj_buf __maybe_unused,
 #endif
 
 static char *
-compose_source(void)
+compose_source(const char *raw_source)
 {
 	struct utsname utsname;
 	int version, patchlevel, sublevel, err;
@@ -56,25 +72,27 @@ compose_source(void)
 
 	version_code = (version << 16) + (patchlevel << 8) + sublevel;
 	err = asprintf(&code, "#define LINUX_VERSION_CODE 0x%08lx;\n%s",
-		       version_code, test_llvm__bpf_prog);
+		       version_code, raw_source);
 	if (err < 0)
 		return NULL;
 
 	return code;
 }
 
-#define SHARED_BUF_INIT_SIZE	(1 << 20)
-struct test_llvm__bpf_result *p_test_llvm__bpf_result;
 
-int test__llvm(void)
+static int __test__llvm(int i)
 {
-	char *tmpl_new, *clang_opt_new;
 	void *obj_buf;
 	size_t obj_buf_sz;
 	int err, old_verbose;
-	char *source;
+	const char *tmpl_old, *clang_opt_old;
+	char *tmpl_new, *clang_opt_new, *source;
+	const char *raw_source = llvm_testcases[i].source;
+	struct test_llvm__bpf_result *result = llvm_testcases[i].result;
 
 	perf_config(perf_config_cb, NULL);
+	clang_opt_old = llvm_param.clang_opt;
+	tmpl_old = llvm_param.clang_bpf_cmd_template;
 
 	/*
 	 * Skip this test if user's .perfconfig doesn't set [llvm] section
@@ -99,15 +117,17 @@ int test__llvm(void)
 	if (!llvm_param.clang_opt)
 		llvm_param.clang_opt = strdup("");
 
-	source = compose_source();
+	source = compose_source(raw_source);
 	if (!source) {
 		pr_err("Failed to compose source code\n");
 		return -1;
 	}
 
 	/* Quote __EOF__ so strings in source won't be expanded by shell */
-	err = asprintf(&tmpl_new, "cat << '__EOF__' | %s\n%s\n__EOF__\n",
-		       llvm_param.clang_bpf_cmd_template, source);
+	err = asprintf(&tmpl_new, "cat << '__EOF__' | %s %s \n%s\n__EOF__\n",
+		       llvm_param.clang_bpf_cmd_template,
+		       !old_verbose ? "2>/dev/null" : "",
+		       source);
 	free(source);
 	source = NULL;
 	if (err < 0) {
@@ -123,73 +143,123 @@ int test__llvm(void)
 	llvm_param.clang_opt = clang_opt_new;
 	err = llvm__compile_bpf("-", &obj_buf, &obj_buf_sz);
 
+	free((void *)llvm_param.clang_bpf_cmd_template);
+	free((void *)llvm_param.clang_opt);
+	llvm_param.clang_bpf_cmd_template = tmpl_old;
+	llvm_param.clang_opt = clang_opt_old;
+
 	verbose = old_verbose;
-	if (err) {
-		if (!verbose)
-			fprintf(stderr, " (use -v to see error message)");
+	if (err)
 		return -1;
-	}
 
 	err = test__bpf_parsing(obj_buf, obj_buf_sz);
-	if (!err && p_test_llvm__bpf_result) {
+	if (!err && result) {
 		if (obj_buf_sz > SHARED_BUF_INIT_SIZE) {
 			pr_err("Resulting object too large\n");
 		} else {
-			p_test_llvm__bpf_result->size = obj_buf_sz;
-			memcpy(p_test_llvm__bpf_result->object,
-			       obj_buf, obj_buf_sz);
+			result->size = obj_buf_sz;
+			memcpy(result->object, obj_buf, obj_buf_sz);
 		}
 	}
 	free(obj_buf);
 	return err;
 }
 
+int test__llvm(void)
+{
+	int i, ret;
+
+	for (i = 0; llvm_testcases[i].source; i++) {
+		ret = __test__llvm(i);
+		if (i == 0 && ret) {
+			/*
+			 * First testcase tests basic LLVM compiling. If it
+			 * fails, no need to check others.
+			 */
+			if (!verbose)
+				fprintf(stderr, " (use -v to see error message)");
+			return ret;
+		} else if (ret) {
+			if (!verbose && llvm_testcases[i].errmsg)
+				fprintf(stderr, " (%s)", llvm_testcases[i].errmsg);
+			return 0;
+		}
+	}
+	return 0;
+}
+
 void test__llvm_prepare(void)
 {
-	p_test_llvm__bpf_result = mmap(NULL, SHARED_BUF_INIT_SIZE,
-				       PROT_READ | PROT_WRITE,
-				       MAP_SHARED | MAP_ANONYMOUS, -1, 0);
-	if (!p_test_llvm__bpf_result)
-		return;
-	memset((void *)p_test_llvm__bpf_result, '\0', SHARED_BUF_INIT_SIZE);
+	int i;
+
+	for (i = 0; llvm_testcases[i].source; i++) {
+		struct test_llvm__bpf_result *result;
+
+		result = mmap(NULL, SHARED_BUF_INIT_SIZE,
+			      PROT_READ | PROT_WRITE,
+			      MAP_SHARED | MAP_ANONYMOUS, -1, 0);
+		if (!result)
+			return;
+		memset((void *)result, '\0', SHARED_BUF_INIT_SIZE);
+
+		llvm_testcases[i].result = result;
+	}
 }
 
 void test__llvm_cleanup(void)
 {
-	unsigned long boundary, buf_end;
+	int i;
 
-	if (!p_test_llvm__bpf_result)
-		return;
-	if (p_test_llvm__bpf_result->size == 0) {
-		munmap((void *)p_test_llvm__bpf_result, SHARED_BUF_INIT_SIZE);
-		p_test_llvm__bpf_result = NULL;
-		return;
-	}
+	for (i = 0; llvm_testcases[i].source; i++) {
+		struct test_llvm__bpf_result *result;
+		unsigned long boundary, buf_end;
 
-	buf_end = (unsigned long)p_test_llvm__bpf_result + SHARED_BUF_INIT_SIZE;
+		result = llvm_testcases[i].result;
+		llvm_testcases[i].tried = true;
 
-	boundary = (unsigned long)(p_test_llvm__bpf_result);
-	boundary += p_test_llvm__bpf_result->size;
-	boundary = (boundary + (page_size - 1)) &
+		if (!result)
+			continue;
+
+		if (result->size == 0) {
+			munmap((void *)result, SHARED_BUF_INIT_SIZE);
+			result = NULL;
+			llvm_testcases[i].result = NULL;
+			continue;
+		}
+
+		buf_end = (unsigned long)result + SHARED_BUF_INIT_SIZE;
+
+		boundary = (unsigned long)(result);
+		boundary += result->size;
+		boundary = (boundary + (page_size - 1)) &
 			(~((unsigned long)page_size - 1));
-	munmap((void *)boundary, buf_end - boundary);
+		munmap((void *)boundary, buf_end - boundary);
+	}
 }
 
 void
-test_llvm__fetch_bpf_obj(void **p_obj_buf, size_t *p_obj_buf_sz)
+test_llvm__fetch_bpf_obj(void **p_obj_buf, size_t *p_obj_buf_sz, int index)
 {
+	struct test_llvm__bpf_result *result;
+
 	*p_obj_buf = NULL;
 	*p_obj_buf_sz = 0;
 
-	if (!p_test_llvm__bpf_result) {
+	if (index > NR_LLVM_TESTCASES)
+		return;
+
+	result = llvm_testcases[index].result;
+
+	if (!result && !llvm_testcases[index].tried) {
 		test__llvm_prepare();
 		test__llvm();
 		test__llvm_cleanup();
 	}
 
-	if (!p_test_llvm__bpf_result)
+	result = llvm_testcases[index].result;
+	if (!result)
 		return;
 
-	*p_obj_buf = p_test_llvm__bpf_result->object;
-	*p_obj_buf_sz = p_test_llvm__bpf_result->size;
+	*p_obj_buf = result->object;
+	*p_obj_buf_sz = result->size;
 }
diff --git a/tools/perf/tests/llvm.h b/tools/perf/tests/llvm.h
index 2fd7ed6..78ec01d 100644
--- a/tools/perf/tests/llvm.h
+++ b/tools/perf/tests/llvm.h
@@ -8,8 +8,14 @@ struct test_llvm__bpf_result {
 	char object[];
 };
 
-extern struct test_llvm__bpf_result *p_test_llvm__bpf_result;
 extern const char test_llvm__bpf_prog[];
-void test_llvm__fetch_bpf_obj(void **p_obj_buf, size_t *p_obj_buf_sz);
+extern const char test_llvm__bpf_test_kbuild_prog[];
+
+enum test_llvm__testcase {
+	LLVM_TESTCASE_BASE,
+	LLVM_TESTCASE_KBUILD,
+	NR_LLVM_TESTCASES,
+};
+void test_llvm__fetch_bpf_obj(void **p_obj_buf, size_t *p_obj_buf_sz, int index);
 
 #endif
-- 
1.8.3.4

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[toc] | [prev] | [next] | [standalone]

#1231369 — [PATCH 22/22] perf probe: Fix module probing with shortname

FromWang Nan <wangnan0@huawei.com>
Date2015-09-23 13:30 +0200
Subject[PATCH 22/22] perf probe: Fix module probing with shortname
Message-ID<qbQpm-2GS-57@gated-at.bofh.it>
In reply to#1231364
After commit 3d39ac538629e4f00a6e1c38d46346f1b8e69505 ("perf machine:
No need to have two DSOs lists"), perf probe with module short name doesn't
work again. For example:

 # lsmod | grep e1000e
 e1000e                233472  0

 # cat /proc/modules | grep e1000e
 e1000e 233472 0 - Live 0xffffffffa0073000

 # cat /proc/kallsyms | grep '\<e1000e_up\>'
 ffffffffa0093860 t e1000e_up[e1000e]

 # perf probe -v -m e1000e --add e1000e_up
 probe-definition(0): e1000e_up
 symbol:e1000e_up file:(null) line:0 offset:0 return:0 lazy:(null)
 0 arguments
 Failed to find module e1000e.
 Could not open debuginfo. Try to use symbols.
 Looking at the vmlinux_path (7 entries long)
 Using /lib/modules/4.2.0-rc7+/build/vmlinux for symbols
 e1000e_up is out of .text, skip it.
   Error: Failed to add events. Reason: No such file or directory (Code: -2)

This is caused by a misunderstood of dso->kernel in kernel_get_module_dso()
that, for kernel module, dso->kernel is DSO_TYPE_USER. dso->kernel is DSO_TYPE_KERNEL
iff dso is vmlinux.

This patch fix 'perf probe -m' with an ad-hoc way.

After this patch:

 # perf probe -v -m e1000e --add e1000e_up
 probe-definition(0): e1000e_up
 symbol:e1000e_up file:(null) line:0 offset:0 return:0 lazy:(null)
 0 arguments
 Open Debuginfo file: /lib/modules/4.2.0-rc7+/kernel/drivers/net/ethernet/intel/e1000e/e1000e.ko
 Try to find probe point from debuginfo.
 Matched function: e1000e_up
 Probe point found: e1000e_up+0
 Found 1 probe_trace_events.
 Opening /sys/kernel/debug/tracing//kprobe_events write=1
 Writing event: p:probe/e1000e_up e1000e:e1000e_up+0
 Added new event:
   probe:e1000e_up      (on e1000e_up in e1000e)

 You can now use it in all perf tools, such as:

 	perf record -e probe:e1000e_up -aR sleep 1

 # perf probe -l
 Failed to find debug information for address ffffffffa0093860
   probe:e1000e_up      (on e1000e_up in e1000e)

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Link: http://lkml.kernel.org/n/ebpf-6yw9eg0ej3l4jnqhinngkw86@git.kernel.org
---
 tools/perf/util/probe-event.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index 2b78e8f..c7d6d3d 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -270,7 +270,7 @@ static int kernel_get_module_dso(const char *module, struct dso **pdso)
 
 	if (module) {
 		list_for_each_entry(dso, &host_machine->dsos.head, node) {
-			if (!dso->kernel)
+			if (dso->kernel)
 				continue;
 			if (strncmp(dso->short_name + 1, module,
 				    dso->short_name_len - 2) == 0)
-- 
1.8.3.4

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[toc] | [prev] | [next] | [standalone]

#1231450

FromArnaldo Carvalho de Melo <acme@redhat.com>
Date2015-09-23 15:50 +0200
Message-ID<qbSAO-5Me-9@gated-at.bofh.it>
In reply to#1231364
Em Wed, Sep 23, 2015 at 11:22:21AM +0000, Wang Nan escreveu:
> Hi Arnaldo,
> 
>    I hope you would be satisified with this weeks pull request. In this
> patchset, we totally get rid of dummy events by utilizing Namhyung's newest
> perf probing API.
> 
> Patch 1-6 are different from previous patchset. Plase have a look.
> 
> Due to some reason I can't access my kernel.org account in my company today,
> so I reuse my github repository. I'll update my kernel.org tree at home.
> 
> I'll have a long vacation from Sept. 24. I hope I can discuss with you with
> my private email. However, It seems impossible to modify code and test until
> Oct. 7. If you find some small problem, could you please help me fix them?

Sure thing, I'll continue working on this, we'll get there :-)
 
> Thank you.
> 
> The following changes since commit 5933944f697c15d6f1fb16dc22c02aac9d2ec206:
> 
>   perf tools: Make perf depend on libbpf (2015-09-22 10:17:01 -0300)
> 
> are available in the git repository at:
> 
>   https://github.com/WangNan0/linux.git tags/perf-ebpf-for-acme-20150923
> 
> for you to fetch changes up to 1465cf7b201b8b21c61fa54ffe15094f66e73ab0:
> 
>   perf probe: Fix module probing with shortname (2015-09-23 10:44:58 +0000)
> 
> ----------------------------------------------------------------
> Get rid of dummy events by utilizing new perf probe API.
> 
> Signed-off-by: Wang Nan <wangnan0@huawei.com>
> 
> ----------------------------------------------------------------
> He Kuang (2):
>       perf tools: Add prologue for BPF programs for fetching arguments
>       perf record: Support custom vmlinux path
> 
> Wang Nan (20):
>       perf ebpf: Add the libbpf glue
>       perf tools: Enable passing bpf object file to --event
>       perf record, bpf: Create probe points for BPF programs
>       perf record: Load eBPF object into kernel
>       perf tools: Collect perf_evsel in BPF object files
>       perf tools: Attach eBPF program to perf event
>       perf record: Add clang options for compiling BPF scripts
>       perf tools: Compile scriptlets to BPF objects when passing '.c' to --event
>       perf test: Enforce LLVM test for BPF test
>       perf test: Add 'perf test BPF'
>       perf probe: Reset args and nargs for probe_trace_event when failure
>       bpf tools: Load a program with different instances using preprocessor
>       perf tools: Add BPF_PROLOGUE config options for further patches
>       perf tools: Compile dwarf-regs.c if CONFIG_BPF_PROLOGUE is on
>       perf tools: Generate prologue for BPF programs
>       perf tools: Use same BPF program if arguments are identical
>       perf tools: Allow BPF program attach to uprobe events
>       perf test: Enforce LLVM test, add kbuild test
>       perf test: Test BPF prologue
>       perf probe: Fix module probing with shortname
> 
>  tools/lib/bpf/libbpf.c                      | 143 +++++-
>  tools/lib/bpf/libbpf.h                      |  22 +
>  tools/perf/arch/x86/util/Build              |   1 +
>  tools/perf/builtin-record.c                 |  11 +
>  tools/perf/config/Makefile                  |  12 +
>  tools/perf/perf.c                           |   2 +
>  tools/perf/tests/Build                      |  24 +-
>  tools/perf/tests/bpf-script-example.c       |  48 ++
>  tools/perf/tests/bpf-script-test-kbuild.c   |  21 +
>  tools/perf/tests/bpf-script-test-prologue.c |  35 ++
>  tools/perf/tests/bpf.c                      | 227 ++++++++++
>  tools/perf/tests/builtin-test.c             |  12 +
>  tools/perf/tests/llvm.c                     | 210 ++++++++-
>  tools/perf/tests/llvm.h                     |  29 ++
>  tools/perf/tests/tests.h                    |   3 +
>  tools/perf/util/Build                       |   2 +
>  tools/perf/util/bpf-loader.c                | 676 ++++++++++++++++++++++++++++
>  tools/perf/util/bpf-loader.h                |  95 ++++
>  tools/perf/util/bpf-prologue.c              | 443 ++++++++++++++++++
>  tools/perf/util/bpf-prologue.h              |  34 ++
>  tools/perf/util/evsel.c                     |  17 +
>  tools/perf/util/evsel.h                     |   1 +
>  tools/perf/util/parse-events.c              | 115 +++++
>  tools/perf/util/parse-events.h              |   9 +
>  tools/perf/util/parse-events.l              |   6 +
>  tools/perf/util/parse-events.y              |  29 +-
>  tools/perf/util/probe-event.c               |   2 +-
>  tools/perf/util/probe-finder.c              |   4 +
>  28 files changed, 2202 insertions(+), 31 deletions(-)
>  create mode 100644 tools/perf/tests/bpf-script-example.c
>  create mode 100644 tools/perf/tests/bpf-script-test-kbuild.c
>  create mode 100644 tools/perf/tests/bpf-script-test-prologue.c
>  create mode 100644 tools/perf/tests/bpf.c
>  create mode 100644 tools/perf/tests/llvm.h
>  create mode 100644 tools/perf/util/bpf-loader.c
>  create mode 100644 tools/perf/util/bpf-loader.h
>  create mode 100644 tools/perf/util/bpf-prologue.c
>  create mode 100644 tools/perf/util/bpf-prologue.h
> -- 
> 1.8.3.4
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[toc] | [prev] | [standalone]

Back to top | Article view | linux.kernel

csiph-web