[GIT PULL 00/19] perf/core fixes and improvements

[GIT PULL 00/19] perf/core fixes and improvements

[Arnaldo Carvalho de Melo]

Hi Ingo,

	Please consider pulling,

Best Regards,

- Arnaldo

The following changes since commit 6e0f17be0361444862637e8986c8c1a3b3f8dcf8:

  Merge branch 'tip/perf/core' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace into perf/core (2012-07-18 11:18:00 +0200)

are available in the git repository at:


  git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux tags/perf-core-for-mingo

for you to fetch changes up to 8696329b7bcf32e69ad12d5975ad1497936d43ec:

  perf annotate: Prevent overflow in size calculation (2012-07-25 13:06:42 -0300)

----------------------------------------------------------------
perf/core fixes and improvements:

. libtraceevent build fixes from Namhyung Kim

. Prevent overflow when calculating annotation buckets size, from Cody Schafer

. Set breakpoint events sample period to 1, just like trace events, from Jovi Zhang

. Fix strerror_r usage, from Kirill Shutemov

. Fix duplicate function declaration problems with bison 2.6, from Kirill Shutemov

. Add DSO caching facility (and perf test entry) to speed up binary file
  reading, will be used by the DWARF unwind code, from Jiri Olsa

. Fix trace event storms by setting PERF_SAMPLE_PERIOD, from Frederic Weisbecker

. perf kvm fixes from David Ahern

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

----------------------------------------------------------------
Cody Schafer (1):
      perf annotate: Prevent overflow in size calculation

David Ahern (6):
      perf symbols: Add machine id to modules debug message
      perf kvm: Set name for VM process in guest machine
      perf kvm: Guest userspace samples should not be lumped with host uspace
      perf kvm: Fix bug resolving guest kernel syms
      perf kvm: Limit repetitive guestmount message to once per directory
      perf tools: Dump exclude_{guest,host}, precise_ip header info too

Frederic Weisbecker (3):
      perf hists: Return correct number of characters printed in callchain
      perf tools: Fix trace events storms due to weight demux
      perf hists: Print newline between hists callchains

Jiri Olsa (4):
      perf symbols: Factor DSO symtab types to generic binary types
      perf symbols: Add interface to read DSO image data
      perf symbols: Add dso data caching
      perf test: Add dso data caching tests

Jovi Zhang (1):
      perf tools: Make the breakpoint events sample period default to 1

Kirill A. Shutemov (2):
      perf tools: use XSI-complaint version of strerror_r() instead of GNU-specific
      perf tools: Fix build error with bison 2.6

Namhyung Kim (2):
      tools lib traceevent: Detect build environment changes
      tools lib traceevent: Ignore TRACEEVENT-CFLAGS file

 tools/lib/traceevent/.gitignore |    1 +
 tools/lib/traceevent/Makefile   |   14 +-
 tools/perf/Makefile             |    4 +
 tools/perf/builtin-test.c       |    4 +
 tools/perf/builtin-top.c        |    2 +-
 tools/perf/ui/browsers/hists.c  |    4 +-
 tools/perf/util/annotate.c      |   15 +-
 tools/perf/util/dso-test-data.c |  153 ++++++++++++++
 tools/perf/util/evlist.c        |    2 +-
 tools/perf/util/header.c        |    6 +
 tools/perf/util/hist.c          |    7 +-
 tools/perf/util/map.c           |   41 +++-
 tools/perf/util/map.h           |    1 +
 tools/perf/util/parse-events.c  |    2 +
 tools/perf/util/session.c       |    5 +-
 tools/perf/util/symbol.c        |  447 +++++++++++++++++++++++++++++++--------
 tools/perf/util/symbol.h        |   54 +++--
 tools/perf/util/target.c        |   11 +-
 18 files changed, 657 insertions(+), 116 deletions(-)
 create mode 100644 tools/lib/traceevent/.gitignore
 create mode 100644 tools/perf/util/dso-test-data.c

[PATCH 01/19] perf symbols: Add machine id to modules debug message

[Arnaldo Carvalho de Melo]

From: David Ahern <dsahern@gmail.com>

Current debug message is:
Problems creating module maps, continuing anyway...

When running multiple VMs it would be nice to know which machine the
message is referring to:

$ perf kvm --guest --guestmount=/tmp/guest-mount record -av -- sleep 10
Problems creating module maps for guest 6613, continuing anyway...

Signed-off-by: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1342826756-64663-2-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/util/symbol.c |   11 +++++++++--
 1 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 50958bb..66c132e 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -2564,8 +2564,15 @@ int machine__create_kernel_maps(struct machine *machine)
 	    __machine__create_kernel_maps(machine, kernel) < 0)
 		return -1;
 
-	if (symbol_conf.use_modules && machine__create_modules(machine) < 0)
-		pr_debug("Problems creating module maps, continuing anyway...\n");
+	if (symbol_conf.use_modules && machine__create_modules(machine) < 0) {
+		if (machine__is_host(machine))
+			pr_debug("Problems creating module maps, "
+				 "continuing anyway...\n");
+		else
+			pr_debug("Problems creating module maps for guest %d, "
+				 "continuing anyway...\n", machine->pid);
+	}
+
 	/*
 	 * Now that we have all the maps created, just set the ->end of them:
 	 */
-- 
1.7.1

[PATCH 02/19] perf kvm: Set name for VM process in guest machine

[Arnaldo Carvalho de Melo]

From: David Ahern <dsahern@gmail.com>

COMM events are not generated in the context of a guest machine, so the
thread name is never set for the VMM process. For example, the qemu-kvm
name applies to the process in the host machine, not the guest machine.
So, samples for guest machines are currently displayed as:

    99.67%     :5671  [unknown]         [g] 0xffffffff81366b41

where 5671 is the pid of the VMM. With this patch the samples in the guest
machine are shown as:

    18.43%  [guest/5671]  [unknown]           [g] 0xffffffff810d68b7

Tested-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1342826756-64663-3-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/util/map.c |   17 ++++++++++++++++-
 1 files changed, 16 insertions(+), 1 deletions(-)

diff --git a/tools/perf/util/map.c b/tools/perf/util/map.c
index a1f4e36..8668569 100644
--- a/tools/perf/util/map.c
+++ b/tools/perf/util/map.c
@@ -7,6 +7,7 @@
 #include <stdio.h>
 #include <unistd.h>
 #include "map.h"
+#include "thread.h"
 
 const char *map_type__name[MAP__NR_TYPES] = {
 	[MAP__FUNCTION] = "Functions",
@@ -585,7 +586,21 @@ int machine__init(struct machine *self, const char *root_dir, pid_t pid)
 	self->kmaps.machine = self;
 	self->pid	    = pid;
 	self->root_dir      = strdup(root_dir);
-	return self->root_dir == NULL ? -ENOMEM : 0;
+	if (self->root_dir == NULL)
+		return -ENOMEM;
+
+	if (pid != HOST_KERNEL_ID) {
+		struct thread *thread = machine__findnew_thread(self, pid);
+		char comm[64];
+
+		if (thread == NULL)
+			return -ENOMEM;
+
+		snprintf(comm, sizeof(comm), "[guest/%d]", pid);
+		thread__set_comm(thread, comm);
+	}
+
+	return 0;
 }
 
 static void dsos__delete(struct list_head *self)
-- 
1.7.1

[PATCH 03/19] perf kvm: Guest userspace samples should not be lumped with host uspace

[Arnaldo Carvalho de Melo]

From: David Ahern <dsahern@gmail.com>

e.g., perf kvm --host  --guest report -i perf.data --stdio -D
shows:

1 599127912065356 0x143b8 [0x48]: PERF_RECORD_SAMPLE(IP, 5): 5671/5676: 0x7fdf95a061c0 period: 1 addr: 0
... chain: nr:2
.....  0: ffffffffffffff80
.....  1: fffffffffffffe00
 ... thread: qemu-kvm:5671
 ...... dso: <not found>

(IP, 5) means sample in guest userspace. Those samples should not be lumped
into the VMM's host thread. i.e, the report output:

    56.86%  qemu-kvm  [unknown]         [u] 0x00007fdf95a061c0

With this patch the output emphasizes it is a guest userspace hit:

    56.86%  [guest/5671]  [unknown]         [u] 0x00007fdf95a061c0

Looking at 3 VMs (2 64-bit, 1 32-bit) with each running a CPU bound
process (openssl speed), perf report currently shows:

  93.84%  117726   qemu-kvm  [unknown]   [u] 0x00007fd7dcaea8e5

which is wrong. With this patch you get:

  31.50%   39258   [guest/18772]  [unknown]   [u] 0x00007fd7dcaea8e5
  31.50%   39236   [guest/11230]  [unknown]   [u] 0x0000000000a57340
  30.84%   39232   [guest/18395]  [unknown]   [u] 0x00007f66f641e107

Tested-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1342826756-64663-4-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/util/session.c |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index 8e48559..90ee39d 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -918,7 +918,9 @@ static struct machine *
 {
 	const u8 cpumode = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
 
-	if (cpumode == PERF_RECORD_MISC_GUEST_KERNEL && perf_guest) {
+	if (perf_guest &&
+	    ((cpumode == PERF_RECORD_MISC_GUEST_KERNEL) ||
+	     (cpumode == PERF_RECORD_MISC_GUEST_USER))) {
 		u32 pid;
 
 		if (event->header.type == PERF_RECORD_MMAP)
-- 
1.7.1

[PATCH 04/19] perf kvm: Fix bug resolving guest kernel syms

[Arnaldo Carvalho de Melo]

From: David Ahern <dsahern@gmail.com>

Guest kernel symbols are not resolved despite passing the information
needed to resolve them. e.g.,

perf kvm --guest --guestmount=/tmp/guest-mount record -a -- sleep 1
perf kvm --guest --guestmount=/tmp/guest-mount report --stdio

    36.55%  [guest/11399]  [unknown]         [g] 0xffffffff81600bc8
    33.19%  [guest/10474]  [unknown]         [g] 0x00000000c0116e00
    30.26%  [guest/11094]  [unknown]         [g] 0xffffffff8100a288
    43.69%  [guest/10474]  [unknown]         [g] 0x00000000c0103d90
    37.38%  [guest/11399]  [unknown]         [g] 0xffffffff81600bc8
    12.24%  [guest/11094]  [unknown]         [g] 0xffffffff810aa91d
     6.69%  [guest/11094]  [unknown]         [u] 0x00007fa784d721c3

which is just pathetic.

After a maddening 2 days sifting through perf minutia I found it --
id_hdr_size is not initialized for guest machines. This shows up on the
report side as random garbage for the cpu and timestamp, e.g.,

29816 7310572949125804849 0x1ac0 [0x50]: PERF_RECORD_MMAP ...

That messes up the sample sorting such that synthesized guest maps are
processed last.

With this patch you get a much more helpful report:

  12.11%  [guest/11399]  [guest.kernel.kallsyms.11399]  [g] irqtime_account_process_tick
  10.58%  [guest/11399]  [guest.kernel.kallsyms.11399]  [g] run_timer_softirq
   6.95%  [guest/11094]  [guest.kernel.kallsyms.11094]  [g] printk_needs_cpu
   6.50%  [guest/11094]  [guest.kernel.kallsyms.11094]  [g] do_timer
   6.45%  [guest/11399]  [guest.kernel.kallsyms.11399]  [g] idle_balance
   4.90%  [guest/11094]  [guest.kernel.kallsyms.11094]  [g] native_read_tsc
    ...

v2:
- changed rbtree walk to use rb_first per Namhyung's suggestion

Tested-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1342826756-64663-5-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/util/map.c     |   13 +++++++++++++
 tools/perf/util/map.h     |    1 +
 tools/perf/util/session.c |    1 +
 3 files changed, 15 insertions(+), 0 deletions(-)

diff --git a/tools/perf/util/map.c b/tools/perf/util/map.c
index 8668569..16d783d 100644
--- a/tools/perf/util/map.c
+++ b/tools/perf/util/map.c
@@ -729,3 +729,16 @@ char *machine__mmap_name(struct machine *self, char *bf, size_t size)
 
 	return bf;
 }
+
+void machines__set_id_hdr_size(struct rb_root *machines, u16 id_hdr_size)
+{
+	struct rb_node *node;
+	struct machine *machine;
+
+	for (node = rb_first(machines); node; node = rb_next(node)) {
+		machine = rb_entry(node, struct machine, rb_node);
+		machine->id_hdr_size = id_hdr_size;
+	}
+
+	return;
+}
diff --git a/tools/perf/util/map.h b/tools/perf/util/map.h
index c14c665..03a1e9b 100644
--- a/tools/perf/util/map.h
+++ b/tools/perf/util/map.h
@@ -151,6 +151,7 @@ struct machine *machines__add(struct rb_root *self, pid_t pid,
 struct machine *machines__find_host(struct rb_root *self);
 struct machine *machines__find(struct rb_root *self, pid_t pid);
 struct machine *machines__findnew(struct rb_root *self, pid_t pid);
+void machines__set_id_hdr_size(struct rb_root *self, u16 id_hdr_size);
 char *machine__mmap_name(struct machine *self, char *bf, size_t size);
 int machine__init(struct machine *self, const char *root_dir, pid_t pid);
 void machine__exit(struct machine *self);
diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index 90ee39d..8e4f075 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -87,6 +87,7 @@ void perf_session__update_sample_type(struct perf_session *self)
 	self->sample_id_all = perf_evlist__sample_id_all(self->evlist);
 	self->id_hdr_size = perf_evlist__id_hdr_size(self->evlist);
 	self->host_machine.id_hdr_size = self->id_hdr_size;
+	machines__set_id_hdr_size(&self->machines, self->id_hdr_size);
 }
 
 int perf_session__create_kernel_maps(struct perf_session *self)
-- 
1.7.1

[PATCH 05/19] perf kvm: Limit repetitive guestmount message to once per directory

[Arnaldo Carvalho de Melo]

From: David Ahern <dsahern@gmail.com>

After 7ed97ad use of the guestmount option without a subdir for *each*
VM generates an error message for each sample related to that VM. Once
per VM is enough.

Signed-off-by: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1342826756-64663-7-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/util/map.c |   11 ++++++++++-
 1 files changed, 10 insertions(+), 1 deletions(-)

diff --git a/tools/perf/util/map.c b/tools/perf/util/map.c
index 16d783d..cc33486 100644
--- a/tools/perf/util/map.c
+++ b/tools/perf/util/map.c
@@ -8,6 +8,7 @@
 #include <unistd.h>
 #include "map.h"
 #include "thread.h"
+#include "strlist.h"
 
 const char *map_type__name[MAP__NR_TYPES] = {
 	[MAP__FUNCTION] = "Functions",
@@ -695,7 +696,15 @@ struct machine *machines__findnew(struct rb_root *self, pid_t pid)
 	    (symbol_conf.guestmount)) {
 		sprintf(path, "%s/%d", symbol_conf.guestmount, pid);
 		if (access(path, R_OK)) {
-			pr_err("Can't access file %s\n", path);
+			static struct strlist *seen;
+
+			if (!seen)
+				seen = strlist__new(true, NULL);
+
+			if (!strlist__has_entry(seen, path)) {
+				pr_err("Can't access file %s\n", path);
+				strlist__add(seen, path);
+			}
 			machine = NULL;
 			goto out;
 		}
-- 
1.7.1

[PATCH 06/19] perf tools: Dump exclude_{guest,host}, precise_ip header info too

[Arnaldo Carvalho de Melo]

From: David Ahern <dsahern@gmail.com>

Adds the attributes to the event line in the header dump.
From:
 event : name = cycles, type = 0, config = 0x0, config1 = 0x0,
      config2 = 0x0, excl_usr = 0, excl_kern = 0, ...
to
  event : name = cycles, type = 0, config = 0x0, config1 = 0x0,
      config2 = 0x0, excl_usr = 0, excl_kern = 0, excl_host = 0,
      excl_guest = 0, precise_ip = 0, ...

Signed-off-by: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1342826756-64663-8-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/util/header.c |    6 ++++++
 1 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index 5a47aba..3a6d204 100644
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -1212,6 +1212,12 @@ static void print_event_desc(struct perf_header *ph, int fd, FILE *fp)
 				attr.exclude_user,
 				attr.exclude_kernel);
 
+		fprintf(fp, ", excl_host = %d, excl_guest = %d",
+				attr.exclude_host,
+				attr.exclude_guest);
+
+		fprintf(fp, ", precise_ip = %d", attr.precise_ip);
+
 		if (nr)
 			fprintf(fp, ", id = {");
 
-- 
1.7.1

[PATCH 07/19] perf hists: Return correct number of characters printed in callchain

[Arnaldo Carvalho de Melo]

From: Frederic Weisbecker <fweisbec@gmail.com>

Include the omitted number of characters printed for the first entry.

Not that it really matters because nobody seem to care about the number
of printed characters for now. But just in case.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1342631456-7233-2-git-send-email-fweisbec@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/util/hist.c |    5 +++--
 1 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/tools/perf/util/hist.c b/tools/perf/util/hist.c
index 514e2a4..90dc35a 100644
--- a/tools/perf/util/hist.c
+++ b/tools/perf/util/hist.c
@@ -708,7 +708,7 @@ static size_t callchain__fprintf_graph(FILE *fp, struct rb_root *root,
 	bool printed = false;
 	struct rb_node *node;
 	int i = 0;
-	int ret;
+	int ret = 0;
 
 	/*
 	 * If have one single callchain root, don't bother printing
@@ -747,8 +747,9 @@ static size_t callchain__fprintf_graph(FILE *fp, struct rb_root *root,
 		root = &cnode->rb_root;
 	}
 
-	return __callchain__fprintf_graph(fp, root, total_samples,
+	ret += __callchain__fprintf_graph(fp, root, total_samples,
 					  1, 1, left_margin);
+	return ret;
 }
 
 static size_t __callchain__fprintf_flat(FILE *fp,
-- 
1.7.1

[PATCH 08/19] perf tools: Fix trace events storms due to weight demux

[Arnaldo Carvalho de Melo]

From: Frederic Weisbecker <fweisbec@gmail.com>

Trace events have a period (weight) of 1 by default. This can be
overriden on events definition by using the __perf_count() macro.

For example, the sched_stat_runtime() is weighted with the runtime of
the task that fired the event.

By default, perf handles such weighted event by dividing it into
individual events carrying a weight of 1. For example if
sched_stat_runtime is fired and the task has run 5000000 nsecs, perf
divides it into 5000000 events in the buffer.

This behaviour makes weighted events unusable because they quickly
fullfill the buffers and we lose most events.

The commit 5d81e5cfb37a174e8ddc0413e2e70cdf05807ace ("events: Don't
divide events if it has field period") solves this problem by sending
only one event when PERF_SAMPLE_PERIOD flag is set. The weight is
carried in the sample itself such that we don't need to demultiplex it
anymore.

This patch provides the last missing piece to use this feature by
setting PERF_SAMPLE_PERIOD from perf tools when we deal with trace
events.

Before:
	$ ./perf record -e sched:* -a sleep 1
	[ perf record: Woken up 3 times to write data ]
	[ perf record: Captured and wrote 1.619 MB perf.data (~70749 samples) ]
	Warning:
	Processed 16909 events and lost 1 chunks!

	Check IO/CPU overload!

	$ ./perf script
	perf  1894 [003]   824.898327: sched_migrate_task: comm=perf pid=1898 prio=120 orig_cpu=2 dest_cpu=0
	perf  1894 [003]   824.898335: sched_stat_sleep: comm=perf pid=1898 delay=113179500 [ns]
	perf  1894 [003]   824.898336: sched_stat_sleep: comm=perf pid=1898 delay=113179500 [ns]
	perf  1894 [003]   824.898337: sched_stat_sleep: comm=perf pid=1898 delay=113179500 [ns]
	perf  1894 [003]   824.898338: sched_stat_sleep: comm=perf pid=1898 delay=113179500 [ns]
	perf  1894 [003]   824.898339: sched_stat_sleep: comm=perf pid=1898 delay=113179500 [ns]
	perf  1894 [003]   824.898340: sched_stat_sleep: comm=perf pid=1898 delay=113179500 [ns]
	perf  1894 [003]   824.898341: sched_stat_sleep: comm=perf pid=1898 delay=113179500 [ns]
	[...]

After:
	$ ./perf record -e sched:* -a sleep 1
	[ perf record: Woken up 1 times to write data ]
	[ perf record: Captured and wrote 0.074 MB perf.data (~3228 samples) ]

	$ ./perf script

	perf  1461 [000]   554.286957: sched_migrate_task: comm=perf pid=1465 prio=120 orig_cpu=3 dest_cpu=1
	perf  1461 [000]   554.286964: sched_stat_sleep: comm=perf pid=1465 delay=133047190 [ns]
	perf  1461 [000]   554.286967: sched_wakeup: comm=perf pid=1465 prio=120 success=1 target_cpu=001
	swapper     0 [001]   554.286976: sched_stat_wait: comm=perf pid=1465 delay=0 [ns]
	swapper     0 [001]   554.286983: sched_switch: prev_comm=swapper/1 prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=perf
	[...]

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1342631456-7233-1-git-send-email-fweisbec@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/util/evlist.c       |    2 +-
 tools/perf/util/parse-events.c |    1 +
 2 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
index f74e956..3edfd34 100644
--- a/tools/perf/util/evlist.c
+++ b/tools/perf/util/evlist.c
@@ -214,7 +214,7 @@ int perf_evlist__add_tracepoints(struct perf_evlist *evlist,
 		attrs[i].type	       = PERF_TYPE_TRACEPOINT;
 		attrs[i].config	       = err;
 	        attrs[i].sample_type   = (PERF_SAMPLE_RAW | PERF_SAMPLE_TIME |
-					  PERF_SAMPLE_CPU);
+					  PERF_SAMPLE_CPU | PERF_SAMPLE_PERIOD);
 		attrs[i].sample_period = 1;
 	}
 
diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index 1aa721d..a729945 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -377,6 +377,7 @@ static int add_tracepoint(struct list_head **list, int *idx,
 	attr.sample_type |= PERF_SAMPLE_RAW;
 	attr.sample_type |= PERF_SAMPLE_TIME;
 	attr.sample_type |= PERF_SAMPLE_CPU;
+	attr.sample_type |= PERF_SAMPLE_PERIOD;
 	attr.sample_period = 1;
 
 	snprintf(name, MAX_NAME_LEN, "%s:%s", sys_name, evt_name);
-- 
1.7.1

[PATCH 09/19] perf hists: Print newline between hists callchains

[Arnaldo Carvalho de Melo]

From: Frederic Weisbecker <fweisbec@gmail.com>

Tiny cosmetic fix. The lack of a newline between hists callchains was
looking slightly messy.

Before:

     0.24%      swapper  [kernel.kallsyms]  [k] _raw_spin_lock_irq
                |
                --- _raw_spin_lock_irq
                    run_timer_softirq
                    __do_softirq
                    call_softirq
                    do_softirq
                    irq_exit
                    smp_apic_timer_interrupt
                    apic_timer_interrupt
                    default_idle
                    amd_e400_idle
                    cpu_idle
                    start_secondary
     0.10%         perf  [kernel.kallsyms]  [k] lock_is_held
                   |
                   --- lock_is_held
                       __might_sleep
                       mutex_lock_nested
                       perf_event_for_each_child
                       perf_ioctl
                       do_vfs_ioctl
                       sys_ioctl
                       system_call_fastpath
                       ioctl
                       cmd_record
                       run_builtin
                       main
                       __libc_start_main

After:

     0.24%      swapper  [kernel.kallsyms]  [k] _raw_spin_lock_irq
                |
                --- _raw_spin_lock_irq
                    run_timer_softirq
                    __do_softirq
                    call_softirq
                    do_softirq
                    irq_exit
                    smp_apic_timer_interrupt
                    apic_timer_interrupt
                    default_idle
                    amd_e400_idle
                    cpu_idle
                    start_secondary

     0.10%         perf  [kernel.kallsyms]  [k] lock_is_held
                   |
                   --- lock_is_held
                       __might_sleep
                       mutex_lock_nested
                       perf_event_for_each_child
                       perf_ioctl
                       do_vfs_ioctl
                       sys_ioctl
                       system_call_fastpath
                       ioctl
                       cmd_record
                       run_builtin
                       main
                       __libc_start_main

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1342631456-7233-3-git-send-email-fweisbec@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/util/hist.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/tools/perf/util/hist.c b/tools/perf/util/hist.c
index 90dc35a..f247ef2 100644
--- a/tools/perf/util/hist.c
+++ b/tools/perf/util/hist.c
@@ -749,6 +749,8 @@ static size_t callchain__fprintf_graph(FILE *fp, struct rb_root *root,
 
 	ret += __callchain__fprintf_graph(fp, root, total_samples,
 					  1, 1, left_margin);
+	ret += fprintf(fp, "\n");
+
 	return ret;
 }
 
-- 
1.7.1

[PATCH 10/19] perf symbols: Factor DSO symtab types to generic binary types

[Arnaldo Carvalho de Melo]

From: Jiri Olsa <jolsa@redhat.com>

Adding interface to access DSOs so it could be used
from another place.

New DSO binary type is added - making current SYMTAB__*
types more general:
   DSO_BINARY_TYPE__* = SYMTAB__*

Following function is added to return path based on the specified
binary type:
   dso__binary_type_file

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Arun Sharma <asharma@fb.com>
Cc: Benjamin Redelings <benjamin.redelings@nescent.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Ulrich Drepper <drepper@gmail.com>
Link: http://lkml.kernel.org/r/1342959280-5361-10-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/builtin-top.c   |    2 +-
 tools/perf/util/annotate.c |    2 +-
 tools/perf/util/symbol.c   |  209 ++++++++++++++++++++++++++------------------
 tools/perf/util/symbol.h   |   34 ++++----
 4 files changed, 145 insertions(+), 102 deletions(-)

diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index e3cab5f..35e86c6 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -125,7 +125,7 @@ static int perf_top__parse_source(struct perf_top *top, struct hist_entry *he)
 	/*
 	 * We can't annotate with just /proc/kallsyms
 	 */
-	if (map->dso->symtab_type == SYMTAB__KALLSYMS) {
+	if (map->dso->symtab_type == DSO_BINARY_TYPE__KALLSYMS) {
 		pr_err("Can't annotate %s: No vmlinux file was found in the "
 		       "path\n", sym->name);
 		sleep(1);
diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c
index 8069dfb..7d3641f 100644
--- a/tools/perf/util/annotate.c
+++ b/tools/perf/util/annotate.c
@@ -777,7 +777,7 @@ fallback:
 		free_filename = false;
 	}
 
-	if (dso->symtab_type == SYMTAB__KALLSYMS) {
+	if (dso->symtab_type == DSO_BINARY_TYPE__KALLSYMS) {
 		char bf[BUILD_ID_SIZE * 2 + 16] = " with build id ";
 		char *build_id_msg = NULL;
 
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 66c132e..60677a6 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -48,6 +48,23 @@ struct symbol_conf symbol_conf = {
 	.symfs            = "",
 };
 
+static enum dso_binary_type binary_type_symtab[] = {
+	DSO_BINARY_TYPE__KALLSYMS,
+	DSO_BINARY_TYPE__GUEST_KALLSYMS,
+	DSO_BINARY_TYPE__JAVA_JIT,
+	DSO_BINARY_TYPE__DEBUGLINK,
+	DSO_BINARY_TYPE__BUILD_ID_CACHE,
+	DSO_BINARY_TYPE__FEDORA_DEBUGINFO,
+	DSO_BINARY_TYPE__UBUNTU_DEBUGINFO,
+	DSO_BINARY_TYPE__BUILDID_DEBUGINFO,
+	DSO_BINARY_TYPE__SYSTEM_PATH_DSO,
+	DSO_BINARY_TYPE__GUEST_KMODULE,
+	DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE,
+	DSO_BINARY_TYPE__NOT_FOUND,
+};
+
+#define DSO_BINARY_TYPE__SYMTAB_CNT sizeof(binary_type_symtab)
+
 int dso__name_len(const struct dso *dso)
 {
 	if (!dso)
@@ -318,7 +335,7 @@ struct dso *dso__new(const char *name)
 		dso__set_short_name(dso, dso->name);
 		for (i = 0; i < MAP__NR_TYPES; ++i)
 			dso->symbols[i] = dso->symbol_names[i] = RB_ROOT;
-		dso->symtab_type = SYMTAB__NOT_FOUND;
+		dso->symtab_type = DSO_BINARY_TYPE__NOT_FOUND;
 		dso->loaded = 0;
 		dso->sorted_by_name = 0;
 		dso->has_build_id = 0;
@@ -806,9 +823,9 @@ int dso__load_kallsyms(struct dso *dso, const char *filename,
 	symbols__fixup_end(&dso->symbols[map->type]);
 
 	if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
-		dso->symtab_type = SYMTAB__GUEST_KALLSYMS;
+		dso->symtab_type = DSO_BINARY_TYPE__GUEST_KALLSYMS;
 	else
-		dso->symtab_type = SYMTAB__KALLSYMS;
+		dso->symtab_type = DSO_BINARY_TYPE__KALLSYMS;
 
 	return dso__split_kallsyms(dso, map, filter);
 }
@@ -1660,32 +1677,110 @@ out:
 char dso__symtab_origin(const struct dso *dso)
 {
 	static const char origin[] = {
-		[SYMTAB__KALLSYMS]	      = 'k',
-		[SYMTAB__JAVA_JIT]	      = 'j',
-		[SYMTAB__DEBUGLINK]           = 'l',
-		[SYMTAB__BUILD_ID_CACHE]      = 'B',
-		[SYMTAB__FEDORA_DEBUGINFO]    = 'f',
-		[SYMTAB__UBUNTU_DEBUGINFO]    = 'u',
-		[SYMTAB__BUILDID_DEBUGINFO]   = 'b',
-		[SYMTAB__SYSTEM_PATH_DSO]     = 'd',
-		[SYMTAB__SYSTEM_PATH_KMODULE] = 'K',
-		[SYMTAB__GUEST_KALLSYMS]      =  'g',
-		[SYMTAB__GUEST_KMODULE]	      =  'G',
+		[DSO_BINARY_TYPE__KALLSYMS]		= 'k',
+		[DSO_BINARY_TYPE__JAVA_JIT]		= 'j',
+		[DSO_BINARY_TYPE__DEBUGLINK]		= 'l',
+		[DSO_BINARY_TYPE__BUILD_ID_CACHE]	= 'B',
+		[DSO_BINARY_TYPE__FEDORA_DEBUGINFO]	= 'f',
+		[DSO_BINARY_TYPE__UBUNTU_DEBUGINFO]	= 'u',
+		[DSO_BINARY_TYPE__BUILDID_DEBUGINFO]	= 'b',
+		[DSO_BINARY_TYPE__SYSTEM_PATH_DSO]	= 'd',
+		[DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE]	= 'K',
+		[DSO_BINARY_TYPE__GUEST_KALLSYMS]	= 'g',
+		[DSO_BINARY_TYPE__GUEST_KMODULE]	= 'G',
 	};
 
-	if (dso == NULL || dso->symtab_type == SYMTAB__NOT_FOUND)
+	if (dso == NULL || dso->symtab_type == DSO_BINARY_TYPE__NOT_FOUND)
 		return '!';
 	return origin[dso->symtab_type];
 }
 
+int dso__binary_type_file(struct dso *dso, enum dso_binary_type type,
+			  char *root_dir, char *file, size_t size)
+{
+	char build_id_hex[BUILD_ID_SIZE * 2 + 1];
+	int ret = 0;
+
+	switch (type) {
+	case DSO_BINARY_TYPE__DEBUGLINK: {
+		char *debuglink;
+
+		strncpy(file, dso->long_name, size);
+		debuglink = file + dso->long_name_len;
+		while (debuglink != file && *debuglink != '/')
+			debuglink--;
+		if (*debuglink == '/')
+			debuglink++;
+		filename__read_debuglink(dso->long_name, debuglink,
+					 size - (debuglink - file));
+		}
+		break;
+	case DSO_BINARY_TYPE__BUILD_ID_CACHE:
+		/* skip the locally configured cache if a symfs is given */
+		if (symbol_conf.symfs[0] ||
+		    (dso__build_id_filename(dso, file, size) == NULL))
+			ret = -1;
+		break;
+
+	case DSO_BINARY_TYPE__FEDORA_DEBUGINFO:
+		snprintf(file, size, "%s/usr/lib/debug%s.debug",
+			 symbol_conf.symfs, dso->long_name);
+		break;
+
+	case DSO_BINARY_TYPE__UBUNTU_DEBUGINFO:
+		snprintf(file, size, "%s/usr/lib/debug%s",
+			 symbol_conf.symfs, dso->long_name);
+		break;
+
+	case DSO_BINARY_TYPE__BUILDID_DEBUGINFO:
+		if (!dso->has_build_id) {
+			ret = -1;
+			break;
+		}
+
+		build_id__sprintf(dso->build_id,
+				  sizeof(dso->build_id),
+				  build_id_hex);
+		snprintf(file, size,
+			 "%s/usr/lib/debug/.build-id/%.2s/%s.debug",
+			 symbol_conf.symfs, build_id_hex, build_id_hex + 2);
+		break;
+
+	case DSO_BINARY_TYPE__SYSTEM_PATH_DSO:
+		snprintf(file, size, "%s%s",
+			 symbol_conf.symfs, dso->long_name);
+		break;
+
+	case DSO_BINARY_TYPE__GUEST_KMODULE:
+		snprintf(file, size, "%s%s%s", symbol_conf.symfs,
+			 root_dir, dso->long_name);
+		break;
+
+	case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE:
+		snprintf(file, size, "%s%s", symbol_conf.symfs,
+			 dso->long_name);
+		break;
+
+	default:
+	case DSO_BINARY_TYPE__KALLSYMS:
+	case DSO_BINARY_TYPE__GUEST_KALLSYMS:
+	case DSO_BINARY_TYPE__JAVA_JIT:
+	case DSO_BINARY_TYPE__NOT_FOUND:
+		ret = -1;
+		break;
+	}
+
+	return ret;
+}
+
 int dso__load(struct dso *dso, struct map *map, symbol_filter_t filter)
 {
-	int size = PATH_MAX;
 	char *name;
 	int ret = -1;
 	int fd;
+	u_int i;
 	struct machine *machine;
-	const char *root_dir;
+	char *root_dir = (char *) "";
 	int want_symtab;
 
 	dso__set_loaded(dso, map->type);
@@ -1700,7 +1795,7 @@ int dso__load(struct dso *dso, struct map *map, symbol_filter_t filter)
 	else
 		machine = NULL;
 
-	name = malloc(size);
+	name = malloc(PATH_MAX);
 	if (!name)
 		return -1;
 
@@ -1719,81 +1814,27 @@ int dso__load(struct dso *dso, struct map *map, symbol_filter_t filter)
 		}
 
 		ret = dso__load_perf_map(dso, map, filter);
-		dso->symtab_type = ret > 0 ? SYMTAB__JAVA_JIT :
-					      SYMTAB__NOT_FOUND;
+		dso->symtab_type = ret > 0 ? DSO_BINARY_TYPE__JAVA_JIT :
+					     DSO_BINARY_TYPE__NOT_FOUND;
 		return ret;
 	}
 
+	if (machine)
+		root_dir = machine->root_dir;
+
 	/* Iterate over candidate debug images.
 	 * On the first pass, only load images if they have a full symtab.
 	 * Failing that, do a second pass where we accept .dynsym also
 	 */
 	want_symtab = 1;
 restart:
-	for (dso->symtab_type = SYMTAB__DEBUGLINK;
-	     dso->symtab_type != SYMTAB__NOT_FOUND;
-	     dso->symtab_type++) {
-		switch (dso->symtab_type) {
-		case SYMTAB__DEBUGLINK: {
-			char *debuglink;
-			strncpy(name, dso->long_name, size);
-			debuglink = name + dso->long_name_len;
-			while (debuglink != name && *debuglink != '/')
-				debuglink--;
-			if (*debuglink == '/')
-				debuglink++;
-			filename__read_debuglink(dso->long_name, debuglink,
-						 size - (debuglink - name));
-			}
-			break;
-		case SYMTAB__BUILD_ID_CACHE:
-			/* skip the locally configured cache if a symfs is given */
-			if (symbol_conf.symfs[0] ||
-			    (dso__build_id_filename(dso, name, size) == NULL)) {
-				continue;
-			}
-			break;
-		case SYMTAB__FEDORA_DEBUGINFO:
-			snprintf(name, size, "%s/usr/lib/debug%s.debug",
-				 symbol_conf.symfs, dso->long_name);
-			break;
-		case SYMTAB__UBUNTU_DEBUGINFO:
-			snprintf(name, size, "%s/usr/lib/debug%s",
-				 symbol_conf.symfs, dso->long_name);
-			break;
-		case SYMTAB__BUILDID_DEBUGINFO: {
-			char build_id_hex[BUILD_ID_SIZE * 2 + 1];
-
-			if (!dso->has_build_id)
-				continue;
+	for (i = 0; i < DSO_BINARY_TYPE__SYMTAB_CNT; i++) {
 
-			build_id__sprintf(dso->build_id,
-					  sizeof(dso->build_id),
-					  build_id_hex);
-			snprintf(name, size,
-				 "%s/usr/lib/debug/.build-id/%.2s/%s.debug",
-				 symbol_conf.symfs, build_id_hex, build_id_hex + 2);
-			}
-			break;
-		case SYMTAB__SYSTEM_PATH_DSO:
-			snprintf(name, size, "%s%s",
-			     symbol_conf.symfs, dso->long_name);
-			break;
-		case SYMTAB__GUEST_KMODULE:
-			if (map->groups && machine)
-				root_dir = machine->root_dir;
-			else
-				root_dir = "";
-			snprintf(name, size, "%s%s%s", symbol_conf.symfs,
-				 root_dir, dso->long_name);
-			break;
+		dso->symtab_type = binary_type_symtab[i];
 
-		case SYMTAB__SYSTEM_PATH_KMODULE:
-			snprintf(name, size, "%s%s", symbol_conf.symfs,
-				 dso->long_name);
-			break;
-		default:;
-		}
+		if (dso__binary_type_file(dso, dso->symtab_type,
+					  root_dir, name, PATH_MAX))
+			continue;
 
 		/* Name is now the name of the next image to try */
 		fd = open(name, O_RDONLY);
@@ -2010,9 +2051,9 @@ struct map *machine__new_module(struct machine *machine, u64 start,
 		return NULL;
 
 	if (machine__is_host(machine))
-		dso->symtab_type = SYMTAB__SYSTEM_PATH_KMODULE;
+		dso->symtab_type = DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE;
 	else
-		dso->symtab_type = SYMTAB__GUEST_KMODULE;
+		dso->symtab_type = DSO_BINARY_TYPE__GUEST_KMODULE;
 	map_groups__insert(&machine->kmaps, map);
 	return map;
 }
diff --git a/tools/perf/util/symbol.h b/tools/perf/util/symbol.h
index a884b99..dc474f0 100644
--- a/tools/perf/util/symbol.h
+++ b/tools/perf/util/symbol.h
@@ -155,6 +155,21 @@ struct addr_location {
 	s32	      cpu;
 };
 
+enum dso_binary_type {
+	DSO_BINARY_TYPE__KALLSYMS = 0,
+	DSO_BINARY_TYPE__GUEST_KALLSYMS,
+	DSO_BINARY_TYPE__JAVA_JIT,
+	DSO_BINARY_TYPE__DEBUGLINK,
+	DSO_BINARY_TYPE__BUILD_ID_CACHE,
+	DSO_BINARY_TYPE__FEDORA_DEBUGINFO,
+	DSO_BINARY_TYPE__UBUNTU_DEBUGINFO,
+	DSO_BINARY_TYPE__BUILDID_DEBUGINFO,
+	DSO_BINARY_TYPE__SYSTEM_PATH_DSO,
+	DSO_BINARY_TYPE__GUEST_KMODULE,
+	DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE,
+	DSO_BINARY_TYPE__NOT_FOUND,
+};
+
 enum dso_kernel_type {
 	DSO_TYPE_USER = 0,
 	DSO_TYPE_KERNEL,
@@ -173,13 +188,13 @@ struct dso {
 	struct rb_root	 symbol_names[MAP__NR_TYPES];
 	enum dso_kernel_type	kernel;
 	enum dso_swap_type	needs_swap;
+	enum dso_binary_type	symtab_type;
 	u8		 adjust_symbols:1;
 	u8		 has_build_id:1;
 	u8		 hit:1;
 	u8		 annotate_warned:1;
 	u8		 sname_alloc:1;
 	u8		 lname_alloc:1;
-	unsigned char	 symtab_type;
 	u8		 sorted_by_name;
 	u8		 loaded;
 	u8		 build_id[BUILD_ID_SIZE];
@@ -253,21 +268,6 @@ size_t dso__fprintf_symbols_by_name(struct dso *dso,
 				    enum map_type type, FILE *fp);
 size_t dso__fprintf(struct dso *dso, enum map_type type, FILE *fp);
 
-enum symtab_type {
-	SYMTAB__KALLSYMS = 0,
-	SYMTAB__GUEST_KALLSYMS,
-	SYMTAB__JAVA_JIT,
-	SYMTAB__DEBUGLINK,
-	SYMTAB__BUILD_ID_CACHE,
-	SYMTAB__FEDORA_DEBUGINFO,
-	SYMTAB__UBUNTU_DEBUGINFO,
-	SYMTAB__BUILDID_DEBUGINFO,
-	SYMTAB__SYSTEM_PATH_DSO,
-	SYMTAB__GUEST_KMODULE,
-	SYMTAB__SYSTEM_PATH_KMODULE,
-	SYMTAB__NOT_FOUND,
-};
-
 char dso__symtab_origin(const struct dso *dso);
 void dso__set_long_name(struct dso *dso, char *name);
 void dso__set_build_id(struct dso *dso, void *build_id);
@@ -304,4 +304,6 @@ bool symbol_type__is_a(char symbol_type, enum map_type map_type);
 
 size_t machine__fprintf_vmlinux_path(struct machine *machine, FILE *fp);
 
+int dso__binary_type_file(struct dso *dso, enum dso_binary_type type,
+			  char *root_dir, char *file, size_t size);
 #endif /* __PERF_SYMBOL */
-- 
1.7.1

[PATCH 11/19] perf symbols: Add interface to read DSO image data

[Arnaldo Carvalho de Melo]

From: Jiri Olsa <jolsa@redhat.com>

Adding following interface for DSO object to allow
reading of DSO image data:

  dso__data_fd
    - opens DSO and returns file descriptor
      Binary types are used to locate/open DSO in following order:
        DSO_BINARY_TYPE__BUILD_ID_CACHE
        DSO_BINARY_TYPE__SYSTEM_PATH_DSO
      In other word we first try to open DSO build-id path,
      and if that fails we try to open DSO system path.

  dso__data_read_offset
    - reads DSO data from specified offset

  dso__data_read_addr
    - reads DSO data from specified address/map.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Arun Sharma <asharma@fb.com>
Cc: Benjamin Redelings <benjamin.redelings@nescent.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Ulrich Drepper <drepper@gmail.com>
Link: http://lkml.kernel.org/r/1342959280-5361-11-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/util/symbol.c |  109 ++++++++++++++++++++++++++++++++++++++++++++++
 tools/perf/util/symbol.h |    8 +++
 2 files changed, 117 insertions(+), 0 deletions(-)

diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 60677a6..8131949 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -65,6 +65,14 @@ static enum dso_binary_type binary_type_symtab[] = {
 
 #define DSO_BINARY_TYPE__SYMTAB_CNT sizeof(binary_type_symtab)
 
+static enum dso_binary_type binary_type_data[] = {
+	DSO_BINARY_TYPE__BUILD_ID_CACHE,
+	DSO_BINARY_TYPE__SYSTEM_PATH_DSO,
+	DSO_BINARY_TYPE__NOT_FOUND,
+};
+
+#define DSO_BINARY_TYPE__DATA_CNT sizeof(binary_type_data)
+
 int dso__name_len(const struct dso *dso)
 {
 	if (!dso)
@@ -336,6 +344,7 @@ struct dso *dso__new(const char *name)
 		for (i = 0; i < MAP__NR_TYPES; ++i)
 			dso->symbols[i] = dso->symbol_names[i] = RB_ROOT;
 		dso->symtab_type = DSO_BINARY_TYPE__NOT_FOUND;
+		dso->data_type   = DSO_BINARY_TYPE__NOT_FOUND;
 		dso->loaded = 0;
 		dso->sorted_by_name = 0;
 		dso->has_build_id = 0;
@@ -2953,3 +2962,103 @@ struct map *dso__new_map(const char *name)
 
 	return map;
 }
+
+static int open_dso(struct dso *dso, struct machine *machine)
+{
+	char *root_dir = (char *) "";
+	char *name;
+	int fd;
+
+	name = malloc(PATH_MAX);
+	if (!name)
+		return -ENOMEM;
+
+	if (machine)
+		root_dir = machine->root_dir;
+
+	if (dso__binary_type_file(dso, dso->data_type,
+				  root_dir, name, PATH_MAX)) {
+		free(name);
+		return -EINVAL;
+	}
+
+	fd = open(name, O_RDONLY);
+	free(name);
+	return fd;
+}
+
+int dso__data_fd(struct dso *dso, struct machine *machine)
+{
+	int i = 0;
+
+	if (dso->data_type != DSO_BINARY_TYPE__NOT_FOUND)
+		return open_dso(dso, machine);
+
+	do {
+		int fd;
+
+		dso->data_type = binary_type_data[i++];
+
+		fd = open_dso(dso, machine);
+		if (fd >= 0)
+			return fd;
+
+	} while (dso->data_type != DSO_BINARY_TYPE__NOT_FOUND);
+
+	return -EINVAL;
+}
+
+static ssize_t dso_cache_read(struct dso *dso __used, u64 offset __used,
+			      u8 *data __used, ssize_t size __used)
+{
+	return -EINVAL;
+}
+
+static int dso_cache_add(struct dso *dso __used, u64 offset __used,
+			 u8 *data __used, ssize_t size __used)
+{
+	return 0;
+}
+
+static ssize_t read_dso_data(struct dso *dso, struct machine *machine,
+		     u64 offset, u8 *data, ssize_t size)
+{
+	ssize_t rsize = -1;
+	int fd;
+
+	fd = dso__data_fd(dso, machine);
+	if (fd < 0)
+		return -1;
+
+	do {
+		if (-1 == lseek(fd, offset, SEEK_SET))
+			break;
+
+		rsize = read(fd, data, size);
+		if (-1 == rsize)
+			break;
+
+		if (dso_cache_add(dso, offset, data, size))
+			pr_err("Failed to add data int dso cache.");
+
+	} while (0);
+
+	close(fd);
+	return rsize;
+}
+
+ssize_t dso__data_read_offset(struct dso *dso, struct machine *machine,
+			      u64 offset, u8 *data, ssize_t size)
+{
+	if (dso_cache_read(dso, offset, data, size))
+		return read_dso_data(dso, machine, offset, data, size);
+	return 0;
+}
+
+ssize_t dso__data_read_addr(struct dso *dso, struct map *map,
+			    struct machine *machine, u64 addr,
+			    u8 *data, ssize_t size)
+{
+	u64 offset = map->map_ip(map, addr);
+	return dso__data_read_offset(dso, machine, offset, data, size);
+}
diff --git a/tools/perf/util/symbol.h b/tools/perf/util/symbol.h
index dc474f0..9b9ea00 100644
--- a/tools/perf/util/symbol.h
+++ b/tools/perf/util/symbol.h
@@ -189,6 +189,7 @@ struct dso {
 	enum dso_kernel_type	kernel;
 	enum dso_swap_type	needs_swap;
 	enum dso_binary_type	symtab_type;
+	enum dso_binary_type	data_type;
 	u8		 adjust_symbols:1;
 	u8		 has_build_id:1;
 	u8		 hit:1;
@@ -306,4 +307,11 @@ size_t machine__fprintf_vmlinux_path(struct machine *machine, FILE *fp);
 
 int dso__binary_type_file(struct dso *dso, enum dso_binary_type type,
 			  char *root_dir, char *file, size_t size);
+
+int dso__data_fd(struct dso *dso, struct machine *machine);
+ssize_t dso__data_read_offset(struct dso *dso, struct machine *machine,
+			      u64 offset, u8 *data, ssize_t size);
+ssize_t dso__data_read_addr(struct dso *dso, struct map *map,
+			    struct machine *machine, u64 addr,
+			    u8 *data, ssize_t size);
 #endif /* __PERF_SYMBOL */
-- 
1.7.1

[PATCH 12/19] perf symbols: Add dso data caching

[Arnaldo Carvalho de Melo]

From: Jiri Olsa <jolsa@redhat.com>

Adding dso data caching so we don't need to open/read/close, each time
we want dso data.

The DSO data caching affects following functions:
  dso__data_read_offset
  dso__data_read_addr

Each DSO read tries to find the data (based on offset) inside the cache.
If it's not present it fills the cache from file, and returns the data.
If it is present, data are returned with no file read.

Each data read is cached by reading cache page sized/aligned amount of
DSO data. The cache page size is hardcoded to 4096.  The cache is using
RB tree with file offset as a sort key.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Arun Sharma <asharma@fb.com>
Cc: Benjamin Redelings <benjamin.redelings@nescent.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Ulrich Drepper <drepper@gmail.com>
Link: http://lkml.kernel.org/r/1342959280-5361-17-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/util/symbol.c |  154 ++++++++++++++++++++++++++++++++++++++++------
 tools/perf/util/symbol.h |   11 +++
 2 files changed, 147 insertions(+), 18 deletions(-)

diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 8131949..fdad4ee 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -29,6 +29,7 @@
 #define NT_GNU_BUILD_ID 3
 #endif
 
+static void dso_cache__free(struct rb_root *root);
 static bool dso__build_id_equal(const struct dso *dso, u8 *build_id);
 static int elf_read_build_id(Elf *elf, void *bf, size_t size);
 static void dsos__add(struct list_head *head, struct dso *dso);
@@ -343,6 +344,7 @@ struct dso *dso__new(const char *name)
 		dso__set_short_name(dso, dso->name);
 		for (i = 0; i < MAP__NR_TYPES; ++i)
 			dso->symbols[i] = dso->symbol_names[i] = RB_ROOT;
+		dso->cache = RB_ROOT;
 		dso->symtab_type = DSO_BINARY_TYPE__NOT_FOUND;
 		dso->data_type   = DSO_BINARY_TYPE__NOT_FOUND;
 		dso->loaded = 0;
@@ -378,6 +380,7 @@ void dso__delete(struct dso *dso)
 		free((char *)dso->short_name);
 	if (dso->lname_alloc)
 		free(dso->long_name);
+	dso_cache__free(&dso->cache);
 	free(dso);
 }
 
@@ -3008,22 +3011,87 @@ int dso__data_fd(struct dso *dso, struct machine *machine)
 	return -EINVAL;
 }
 
-static ssize_t dso_cache_read(struct dso *dso __used, u64 offset __used,
-			      u8 *data __used, ssize_t size __used)
+static void
+dso_cache__free(struct rb_root *root)
 {
-	return -EINVAL;
+	struct rb_node *next = rb_first(root);
+
+	while (next) {
+		struct dso_cache *cache;
+
+		cache = rb_entry(next, struct dso_cache, rb_node);
+		next = rb_next(&cache->rb_node);
+		rb_erase(&cache->rb_node, root);
+		free(cache);
+	}
 }
 
-static int dso_cache_add(struct dso *dso __used, u64 offset __used,
-			 u8 *data __used, ssize_t size __used)
+static struct dso_cache*
+dso_cache__find(struct rb_root *root, u64 offset)
 {
-	return 0;
+	struct rb_node **p = &root->rb_node;
+	struct rb_node *parent = NULL;
+	struct dso_cache *cache;
+
+	while (*p != NULL) {
+		u64 end;
+
+		parent = *p;
+		cache = rb_entry(parent, struct dso_cache, rb_node);
+		end = cache->offset + DSO__DATA_CACHE_SIZE;
+
+		if (offset < cache->offset)
+			p = &(*p)->rb_left;
+		else if (offset >= end)
+			p = &(*p)->rb_right;
+		else
+			return cache;
+	}
+	return NULL;
+}
+
+static void
+dso_cache__insert(struct rb_root *root, struct dso_cache *new)
+{
+	struct rb_node **p = &root->rb_node;
+	struct rb_node *parent = NULL;
+	struct dso_cache *cache;
+	u64 offset = new->offset;
+
+	while (*p != NULL) {
+		u64 end;
+
+		parent = *p;
+		cache = rb_entry(parent, struct dso_cache, rb_node);
+		end = cache->offset + DSO__DATA_CACHE_SIZE;
+
+		if (offset < cache->offset)
+			p = &(*p)->rb_left;
+		else if (offset >= end)
+			p = &(*p)->rb_right;
+	}
+
+	rb_link_node(&new->rb_node, parent, p);
+	rb_insert_color(&new->rb_node, root);
+}
+
+static ssize_t
+dso_cache__memcpy(struct dso_cache *cache, u64 offset,
+		  u8 *data, u64 size)
+{
+	u64 cache_offset = offset - cache->offset;
+	u64 cache_size   = min(cache->size - cache_offset, size);
+
+	memcpy(data, cache->data + cache_offset, cache_size);
+	return cache_size;
 }
 
-static ssize_t read_dso_data(struct dso *dso, struct machine *machine,
-		     u64 offset, u8 *data, ssize_t size)
+static ssize_t
+dso_cache__read(struct dso *dso, struct machine *machine,
+		 u64 offset, u8 *data, ssize_t size)
 {
-	ssize_t rsize = -1;
+	struct dso_cache *cache;
+	ssize_t ret;
 	int fd;
 
 	fd = dso__data_fd(dso, machine);
@@ -3031,28 +3099,78 @@ static ssize_t read_dso_data(struct dso *dso, struct machine *machine,
 		return -1;
 
 	do {
-		if (-1 == lseek(fd, offset, SEEK_SET))
+		u64 cache_offset;
+
+		ret = -ENOMEM;
+
+		cache = zalloc(sizeof(*cache) + DSO__DATA_CACHE_SIZE);
+		if (!cache)
 			break;
 
-		rsize = read(fd, data, size);
-		if (-1 == rsize)
+		cache_offset = offset & DSO__DATA_CACHE_MASK;
+		ret = -EINVAL;
+
+		if (-1 == lseek(fd, cache_offset, SEEK_SET))
 			break;
 
-		if (dso_cache_add(dso, offset, data, size))
-			pr_err("Failed to add data int dso cache.");
+		ret = read(fd, cache->data, DSO__DATA_CACHE_SIZE);
+		if (ret <= 0)
+			break;
+
+		cache->offset = cache_offset;
+		cache->size   = ret;
+		dso_cache__insert(&dso->cache, cache);
+
+		ret = dso_cache__memcpy(cache, offset, data, size);
 
 	} while (0);
 
+	if (ret <= 0)
+		free(cache);
+
 	close(fd);
-	return rsize;
+	return ret;
+}
+
+static ssize_t dso_cache_read(struct dso *dso, struct machine *machine,
+			      u64 offset, u8 *data, ssize_t size)
+{
+	struct dso_cache *cache;
+
+	cache = dso_cache__find(&dso->cache, offset);
+	if (cache)
+		return dso_cache__memcpy(cache, offset, data, size);
+	else
+		return dso_cache__read(dso, machine, offset, data, size);
 }
 
 ssize_t dso__data_read_offset(struct dso *dso, struct machine *machine,
 			      u64 offset, u8 *data, ssize_t size)
 {
-	if (dso_cache_read(dso, offset, data, size))
-		return read_dso_data(dso, machine, offset, data, size);
-	return 0;
+	ssize_t r = 0;
+	u8 *p = data;
+
+	do {
+		ssize_t ret;
+
+		ret = dso_cache_read(dso, machine, offset, p, size);
+		if (ret < 0)
+			return ret;
+
+		/* Reached EOF, return what we have. */
+		if (!ret)
+			break;
+
+		BUG_ON(ret > size);
+
+		r      += ret;
+		p      += ret;
+		offset += ret;
+		size   -= ret;
+
+	} while (size);
+
+	return r;
 }
 
 ssize_t dso__data_read_addr(struct dso *dso, struct map *map,
diff --git a/tools/perf/util/symbol.h b/tools/perf/util/symbol.h
index 9b9ea00..980d5f5 100644
--- a/tools/perf/util/symbol.h
+++ b/tools/perf/util/symbol.h
@@ -182,10 +182,21 @@ enum dso_swap_type {
 	DSO_SWAP__YES,
 };
 
+#define DSO__DATA_CACHE_SIZE 4096
+#define DSO__DATA_CACHE_MASK ~(DSO__DATA_CACHE_SIZE - 1)
+
+struct dso_cache {
+	struct rb_node	rb_node;
+	u64 offset;
+	u64 size;
+	char data[0];
+};
+
 struct dso {
 	struct list_head node;
 	struct rb_root	 symbols[MAP__NR_TYPES];
 	struct rb_root	 symbol_names[MAP__NR_TYPES];
+	struct rb_root	 cache;
 	enum dso_kernel_type	kernel;
 	enum dso_swap_type	needs_swap;
 	enum dso_binary_type	symtab_type;
-- 
1.7.1

[PATCH 13/19] perf test: Add dso data caching tests

[Arnaldo Carvalho de Melo]

From: Jiri Olsa <jolsa@redhat.com>

Adding automated test for DSO data reading. Testing raw/cached reads
from different file/cache locations.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Arun Sharma <asharma@fb.com>
Cc: Benjamin Redelings <benjamin.redelings@nescent.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Ulrich Drepper <drepper@gmail.com>
Link: http://lkml.kernel.org/r/1342959280-5361-18-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/Makefile             |    1 +
 tools/perf/builtin-test.c       |    4 +
 tools/perf/util/dso-test-data.c |  153 +++++++++++++++++++++++++++++++++++++++
 tools/perf/util/symbol.h        |    1 +
 4 files changed, 159 insertions(+), 0 deletions(-)
 create mode 100644 tools/perf/util/dso-test-data.c

diff --git a/tools/perf/Makefile b/tools/perf/Makefile
index 75d74e5..e8f0579 100644
--- a/tools/perf/Makefile
+++ b/tools/perf/Makefile
@@ -354,6 +354,7 @@ LIB_OBJS += $(OUTPUT)util/usage.o
 LIB_OBJS += $(OUTPUT)util/wrapper.o
 LIB_OBJS += $(OUTPUT)util/sigchain.o
 LIB_OBJS += $(OUTPUT)util/symbol.o
+LIB_OBJS += $(OUTPUT)util/dso-test-data.o
 LIB_OBJS += $(OUTPUT)util/color.o
 LIB_OBJS += $(OUTPUT)util/pager.o
 LIB_OBJS += $(OUTPUT)util/header.o
diff --git a/tools/perf/builtin-test.c b/tools/perf/builtin-test.c
index 5ce3030..d909eb7 100644
--- a/tools/perf/builtin-test.c
+++ b/tools/perf/builtin-test.c
@@ -1142,6 +1142,10 @@ static struct test {
 		.func = test__perf_pmu,
 	},
 	{
+		.desc = "Test dso data interface",
+		.func = dso__test_data,
+	},
+	{
 		.func = NULL,
 	},
 };
diff --git a/tools/perf/util/dso-test-data.c b/tools/perf/util/dso-test-data.c
new file mode 100644
index 0000000..541cdc7
--- /dev/null
+++ b/tools/perf/util/dso-test-data.c
@@ -0,0 +1,153 @@
+#include "util.h"
+
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <string.h>
+
+#include "symbol.h"
+
+#define TEST_ASSERT_VAL(text, cond) \
+do { \
+	if (!(cond)) { \
+		pr_debug("FAILED %s:%d %s\n", __FILE__, __LINE__, text); \
+		return -1; \
+	} \
+} while (0)
+
+static char *test_file(int size)
+{
+	static char buf_templ[] = "/tmp/test-XXXXXX";
+	char *templ = buf_templ;
+	int fd, i;
+	unsigned char *buf;
+
+	fd = mkostemp(templ, O_CREAT|O_WRONLY|O_TRUNC);
+
+	buf = malloc(size);
+	if (!buf) {
+		close(fd);
+		return NULL;
+	}
+
+	for (i = 0; i < size; i++)
+		buf[i] = (unsigned char) ((int) i % 10);
+
+	if (size != write(fd, buf, size))
+		templ = NULL;
+
+	close(fd);
+	return templ;
+}
+
+#define TEST_FILE_SIZE (DSO__DATA_CACHE_SIZE * 20)
+
+struct test_data_offset {
+	off_t offset;
+	u8 data[10];
+	int size;
+};
+
+struct test_data_offset offsets[] = {
+	/* Fill first cache page. */
+	{
+		.offset = 10,
+		.data   = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 },
+		.size   = 10,
+	},
+	/* Read first cache page. */
+	{
+		.offset = 10,
+		.data   = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 },
+		.size   = 10,
+	},
+	/* Fill cache boundary pages. */
+	{
+		.offset = DSO__DATA_CACHE_SIZE - DSO__DATA_CACHE_SIZE % 10,
+		.data   = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 },
+		.size   = 10,
+	},
+	/* Read cache boundary pages. */
+	{
+		.offset = DSO__DATA_CACHE_SIZE - DSO__DATA_CACHE_SIZE % 10,
+		.data   = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 },
+		.size   = 10,
+	},
+	/* Fill final cache page. */
+	{
+		.offset = TEST_FILE_SIZE - 10,
+		.data   = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 },
+		.size   = 10,
+	},
+	/* Read final cache page. */
+	{
+		.offset = TEST_FILE_SIZE - 10,
+		.data   = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 },
+		.size   = 10,
+	},
+	/* Read final cache page. */
+	{
+		.offset = TEST_FILE_SIZE - 3,
+		.data   = { 7, 8, 9, 0, 0, 0, 0, 0, 0, 0 },
+		.size   = 3,
+	},
+};
+
+int dso__test_data(void)
+{
+	struct machine machine;
+	struct dso *dso;
+	char *file = test_file(TEST_FILE_SIZE);
+	size_t i;
+
+	TEST_ASSERT_VAL("No test file", file);
+
+	memset(&machine, 0, sizeof(machine));
+
+	dso = dso__new((const char *)file);
+
+	/* Basic 10 bytes tests. */
+	for (i = 0; i < ARRAY_SIZE(offsets); i++) {
+		struct test_data_offset *data = &offsets[i];
+		ssize_t size;
+		u8 buf[10];
+
+		memset(buf, 0, 10);
+		size = dso__data_read_offset(dso, &machine, data->offset,
+				     buf, 10);
+
+		TEST_ASSERT_VAL("Wrong size", size == data->size);
+		TEST_ASSERT_VAL("Wrong data", !memcmp(buf, data->data, 10));
+	}
+
+	/* Read cross multiple cache pages. */
+	{
+		ssize_t size;
+		int c;
+		u8 *buf;
+
+		buf = malloc(TEST_FILE_SIZE);
+		TEST_ASSERT_VAL("ENOMEM\n", buf);
+
+		/* First iteration to fill caches, second one to read them. */
+		for (c = 0; c < 2; c++) {
+			memset(buf, 0, TEST_FILE_SIZE);
+			size = dso__data_read_offset(dso, &machine, 10,
+						     buf, TEST_FILE_SIZE);
+
+			TEST_ASSERT_VAL("Wrong size",
+				size == (TEST_FILE_SIZE - 10));
+
+			for (i = 0; i < (size_t)size; i++)
+				TEST_ASSERT_VAL("Wrong data",
+					buf[i] == (i % 10));
+		}
+
+		free(buf);
+	}
+
+	dso__delete(dso);
+	unlink(file);
+	return 0;
+}
diff --git a/tools/perf/util/symbol.h b/tools/perf/util/symbol.h
index 980d5f5..1fe733a 100644
--- a/tools/perf/util/symbol.h
+++ b/tools/perf/util/symbol.h
@@ -325,4 +325,5 @@ ssize_t dso__data_read_offset(struct dso *dso, struct machine *machine,
 ssize_t dso__data_read_addr(struct dso *dso, struct map *map,
 			    struct machine *machine, u64 addr,
 			    u8 *data, ssize_t size);
+int dso__test_data(void);
 #endif /* __PERF_SYMBOL */
-- 
1.7.1

[PATCH 14/19] perf tools: Make the breakpoint events sample period default to 1

[Arnaldo Carvalho de Melo]

From: Jovi Zhang <bookjovi@gmail.com>

There have one problem about hw_breakpoint perf event, as watched, the
events reported to userspace is not correctly, sometime one trigger
bp_event report several events, sometime bp_event cannot go through to
user.

The root cause is attr->freq is 1 passed to kernel defaultly in bp
events, this make kernel calculate event period not as expect, make
sample period to 1 will change attr->freq to 0, to fix this problem.

This patch is similar with commit f92128 about tracepoint events:
    perf: Make the trace events sample period default to 1

Signed-off-by: Jovi Zhang <bookjovi@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/CACV3sbLF8taiCq_VYW-sgRJyupeMzg58C7ZXfMe3xZUiH_Mx6w@mail.gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/util/parse-events.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index a729945..74a5af4 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -490,6 +490,7 @@ int parse_events_add_breakpoint(struct list_head **list, int *idx,
 		attr.bp_len = HW_BREAKPOINT_LEN_4;
 
 	attr.type = PERF_TYPE_BREAKPOINT;
+	attr.sample_period = 1;
 
 	return add_event(list, idx, &attr, NULL);
 }
-- 
1.7.1

[PATCH 15/19] perf tools: use XSI-complaint version of strerror_r() instead of GNU-specific

[Arnaldo Carvalho de Melo]

From: Kirill A. Shutemov <kirill@shutemov.name>

Perf uses GNU-specific version of strerror_r(). The GNU-specific strerror_r()
returns a pointer to a string containing the error message.  This may be either
a pointer to a string that the function stores in buf, or a pointer to some
(immutable) static string (in which case buf is unused).

In glibc-2.16 GNU version was marked with attribute warn_unused_result.  It
triggers few warnings in perf:

util/target.c: In function ‘perf_target__strerror’:
util/target.c:114:13: error: ignoring return value of ‘strerror_r’, declared with attribute warn_unused_result [-Werror=unused-result]
ui/browsers/hists.c: In function ‘hist_browser__dump’:
ui/browsers/hists.c:981:13: error: ignoring return value of ‘strerror_r’, declared with attribute warn_unused_result [-Werror=unused-result]

They are bugs.

Let's fix strerror_r() usage.

Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
Acked-by: Ulrich Drepper <drepper@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ulrich Drepper <drepper@gmail.com>
Link: http://lkml.kernel.org/r/20120723210654.GA25248@shutemov.name
[ committer note: s/assert/BUG_ON/g ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/ui/browsers/hists.c |    4 ++--
 tools/perf/util/target.c       |   11 ++++++++++-
 2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/tools/perf/ui/browsers/hists.c b/tools/perf/ui/browsers/hists.c
index 482f051..413bd62 100644
--- a/tools/perf/ui/browsers/hists.c
+++ b/tools/perf/ui/browsers/hists.c
@@ -978,8 +978,8 @@ static int hist_browser__dump(struct hist_browser *browser)
 	fp = fopen(filename, "w");
 	if (fp == NULL) {
 		char bf[64];
-		strerror_r(errno, bf, sizeof(bf));
-		ui_helpline__fpush("Couldn't write to %s: %s", filename, bf);
+		const char *err = strerror_r(errno, bf, sizeof(bf));
+		ui_helpline__fpush("Couldn't write to %s: %s", filename, err);
 		return -1;
 	}
 
diff --git a/tools/perf/util/target.c b/tools/perf/util/target.c
index 1064d5b..3f59c49 100644
--- a/tools/perf/util/target.c
+++ b/tools/perf/util/target.c
@@ -110,8 +110,17 @@ int perf_target__strerror(struct perf_target *target, int errnum,
 	int idx;
 	const char *msg;
 
+	BUG_ON(buflen > 0);
+
 	if (errnum >= 0) {
-		strerror_r(errnum, buf, buflen);
+		const char *err = strerror_r(errnum, buf, buflen);
+
+		if (err != buf) {
+			size_t len = strlen(err);
+			char *c = mempcpy(buf, err, min(buflen - 1, len));
+			*c = '\0';
+		}
+
 		return 0;
 	}
 
-- 
1.7.1

[PATCH 16/19] perf tools: Fix build error with bison 2.6

[Arnaldo Carvalho de Melo]

From: Kirill A. Shutemov <kirill@shutemov.name>

Bison 2.6 started to generate parse_events_parse() declaration in header. In
this case we have redundant redeclaration:

util/parse-events.c:29:5: error: redundant redeclaration of ‘parse_events_parse’ [-Werror=redundant-decls]
In file included from util/parse-events.c:14:0:
util/parse-events-bison.h:99:5: note: previous declaration of ‘parse_events_parse’ was here
cc1: all warnings being treated as errors

Let's disable -Wredundant-decls for util/parse-events.c since it includes
header we can't control.

Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20120723210407.GA25186@shutemov.name
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/Makefile |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/tools/perf/Makefile b/tools/perf/Makefile
index e8f0579..77f124f 100644
--- a/tools/perf/Makefile
+++ b/tools/perf/Makefile
@@ -804,6 +804,9 @@ $(OUTPUT)ui/browsers/map.o: ui/browsers/map.c $(OUTPUT)PERF-CFLAGS
 $(OUTPUT)util/rbtree.o: ../../lib/rbtree.c $(OUTPUT)PERF-CFLAGS
 	$(QUIET_CC)$(CC) -o $@ -c $(ALL_CFLAGS) -DETC_PERFCONFIG='"$(ETC_PERFCONFIG_SQ)"' $<
 
+$(OUTPUT)util/parse-events.o: util/parse-events.c $(OUTPUT)PERF-CFLAGS
+	$(QUIET_CC)$(CC) -o $@ -c $(ALL_CFLAGS) -Wno-redundant-decls $<
+
 $(OUTPUT)util/scripting-engines/trace-event-perl.o: util/scripting-engines/trace-event-perl.c $(OUTPUT)PERF-CFLAGS
 	$(QUIET_CC)$(CC) -o $@ -c $(ALL_CFLAGS) $(PERL_EMBED_CCOPTS) -Wno-redundant-decls -Wno-strict-prototypes -Wno-unused-parameter -Wno-shadow $<
 
-- 
1.7.1

[PATCH 17/19] tools lib traceevent: Detect build environment changes

[Arnaldo Carvalho de Melo]

From: Namhyung Kim <namhyung.kim@lge.com>

Cross compiling perf requires setting ARCH and CROSS_COMPILE variables,
but libtraceevent couldn't detect the changes so it ends up believing no
recompiling is required. Thus the linker failed like:

     LINK perf
 ../lib/traceevent//libtraceevent.a: member ../lib/traceevent//libtraceevent.a(event-parse.o) in archive is not an object
 collect2: ld returned 1 exit status
 make: *** [perf] Error 1

This patch fixes this by adding TRACEEVENT-CFLAGS file like
PERF-CFLAGS to track those changes.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1341559297-25725-2-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/lib/traceevent/Makefile |   14 ++++++++++++--
 1 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/tools/lib/traceevent/Makefile b/tools/lib/traceevent/Makefile
index 46c2f6b..14131cb 100644
--- a/tools/lib/traceevent/Makefile
+++ b/tools/lib/traceevent/Makefile
@@ -207,7 +207,7 @@ libtraceevent.so: $(PEVENT_LIB_OBJS)
 libtraceevent.a: $(PEVENT_LIB_OBJS)
 	$(Q)$(do_build_static_lib)
 
-$(PEVENT_LIB_OBJS): %.o: $(src)/%.c
+$(PEVENT_LIB_OBJS): %.o: $(src)/%.c TRACEEVENT-CFLAGS
 	$(Q)$(do_fpic_compile)
 
 define make_version.h
@@ -272,6 +272,16 @@ ifneq ($(dep_includes),)
  include $(dep_includes)
 endif
 
+### Detect environment changes
+TRACK_CFLAGS = $(subst ','\'',$(CFLAGS)):$(ARCH):$(CROSS_COMPILE)
+
+TRACEEVENT-CFLAGS: force
+	@FLAGS='$(TRACK_CFLAGS)'; \
+	    if test x"$$FLAGS" != x"`cat TRACEEVENT-CFLAGS 2>/dev/null`" ; then \
+		echo 1>&2 "    * new build flags or cross compiler"; \
+		echo "$$FLAGS" >TRACEEVENT-CFLAGS; \
+            fi
+
 tags:	force
 	$(RM) tags
 	find . -name '*.[ch]' | xargs ctags --extra=+f --c-kinds=+px \
@@ -297,7 +307,7 @@ install: install_lib
 
 clean:
 	$(RM) *.o *~ $(TARGETS) *.a *.so $(VERSION_FILES) .*.d
-	$(RM) tags TAGS
+	$(RM) TRACEEVENT-CFLAGS tags TAGS
 
 endif # skip-makefile
 
-- 
1.7.1

[PATCH 18/19] tools lib traceevent: Ignore TRACEEVENT-CFLAGS file

[Arnaldo Carvalho de Melo]

From: Namhyung Kim <namhyung.kim@lge.com>

The TRACEEVENT-CFLAGS file is used to detect any change on compiler
flags. Just ignore it.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1341559297-25725-3-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/lib/traceevent/.gitignore |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
 create mode 100644 tools/lib/traceevent/.gitignore

diff --git a/tools/lib/traceevent/.gitignore b/tools/lib/traceevent/.gitignore
new file mode 100644
index 0000000..35f56be
--- /dev/null
+++ b/tools/lib/traceevent/.gitignore
@@ -0,0 +1 @@
+TRACEEVENT-CFLAGS
-- 
1.7.1

[PATCH 19/19] perf annotate: Prevent overflow in size calculation

[Arnaldo Carvalho de Melo]

From: Cody Schafer <cody@linux.vnet.ibm.com>

A large enough symbol size causes an overflow in the size parameter to
the histogram allocation, leading to a segfault in
symbol__inc_addr_samples later on when this histogram is accessed.

In the case of being called via perf-report, this returns back and
gracefully ignores the sample, eventually ignoring the chained return
value of perf_session_deliver_event in flush_sample_queue.

Signed-off-by: Cody Schafer <cody@linux.vnet.ibm.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1342753525-4521-1-git-send-email-cody@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/util/annotate.c |   13 ++++++++++++-
 1 files changed, 12 insertions(+), 1 deletions(-)

diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c
index 7d3641f..3a282c0 100644
--- a/tools/perf/util/annotate.c
+++ b/tools/perf/util/annotate.c
@@ -426,7 +426,18 @@ int symbol__alloc_hist(struct symbol *sym)
 {
 	struct annotation *notes = symbol__annotation(sym);
 	const size_t size = symbol__size(sym);
-	size_t sizeof_sym_hist = (sizeof(struct sym_hist) + size * sizeof(u64));
+	size_t sizeof_sym_hist;
+
+	/* Check for overflow when calculating sizeof_sym_hist */
+	if (size > (SIZE_MAX - sizeof(struct sym_hist)) / sizeof(u64))
+		return -1;
+
+	sizeof_sym_hist = (sizeof(struct sym_hist) + size * sizeof(u64));
+
+	/* Check for overflow in zalloc argument */
+	if (sizeof_sym_hist > (SIZE_MAX - sizeof(*notes->src))
+				/ symbol_conf.nr_events)
+		return -1;
 
 	notes->src = zalloc(sizeof(*notes->src) + symbol_conf.nr_events * sizeof_sym_hist);
 	if (notes->src == NULL)
-- 
1.7.1

Re: [PATCH 15/19] perf tools: use XSI-complaint version of strerror_r() instead of GNU-specific

[Kirill A. Shutemov]

Could you take subject from updated patch? This one:

perf: fix strerror_r() usage

-- 
 Kirill A. Shutemov

Re: [PATCH 15/19] perf tools: use XSI-complaint version of strerror_r() instead of GNU-specific

[Arnaldo Carvalho de Melo]

Em Wed, Jul 25, 2012 at 08:54:59PM +0300, Kirill A. Shutemov escreveu:
> Could you take subject from updated patch? This one:
> 
> perf: fix strerror_r() usage

Sorry, missed that :-\ I think it was because you didn't send the new
patch on its own, but keeping the old subject line and inlining the new
patch at the end of the message, please do it next time.

Ingo, what is your take on this, do you want me to fix this up and
resubmit?

- Arnaldo

Re: [PATCH 15/19] perf tools: use XSI-complaint version of strerror_r() instead of GNU-specific

[Ingo Molnar]

* Arnaldo Carvalho de Melo <acme@infradead.org> wrote:

> Em Wed, Jul 25, 2012 at 08:54:59PM +0300, Kirill A. Shutemov escreveu:
> > Could you take subject from updated patch? This one:
> > 
> > perf: fix strerror_r() usage
> 
> Sorry, missed that :-\ I think it was because you didn't send 
> the new patch on its own, but keeping the old subject line and 
> inlining the new patch at the end of the message, please do it 
> next time.
> 
> Ingo, what is your take on this, do you want me to fix this up 
> and resubmit?

I already pulled this one - the old title was usable as well so 
I don't think we want to rebase it just for that reason.

Thanks,

	Ingo

Re: [PATCH 15/19] perf tools: use XSI-complaint version of strerror_r() instead of GNU-specific

[Namhyung Kim]

On Wed, 25 Jul 2012 14:41:30 -0300, Arnaldo Carvalho de Melo wrote:
> From: Kirill A. Shutemov <kirill@shutemov.name>
>
> Perf uses GNU-specific version of strerror_r(). The GNU-specific strerror_r()
> returns a pointer to a string containing the error message.  This may be either
> a pointer to a string that the function stores in buf, or a pointer to some
> (immutable) static string (in which case buf is unused).
>
> In glibc-2.16 GNU version was marked with attribute warn_unused_result.  It
> triggers few warnings in perf:
>
> util/target.c: In function ‘perf_target__strerror’:
> util/target.c:114:13: error: ignoring return value of ‘strerror_r’, declared with attribute warn_unused_result [-Werror=unused-result]
> ui/browsers/hists.c: In function ‘hist_browser__dump’:
> ui/browsers/hists.c:981:13: error: ignoring return value of ‘strerror_r’, declared with attribute warn_unused_result [-Werror=unused-result]
>
> They are bugs.
>
> Let's fix strerror_r() usage.
>
> Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
> Acked-by: Ulrich Drepper <drepper@gmail.com>
> Cc: Ingo Molnar <mingo@kernel.org>
> Cc: Paul Mackerras <paulus@samba.org>
> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
> Cc: Ulrich Drepper <drepper@gmail.com>
> Link: http://lkml.kernel.org/r/20120723210654.GA25248@shutemov.name
> [ committer note: s/assert/BUG_ON/g ]
> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
> ---
>  tools/perf/ui/browsers/hists.c |    4 ++--
>  tools/perf/util/target.c       |   11 ++++++++++-
>  2 files changed, 12 insertions(+), 3 deletions(-)
>
> diff --git a/tools/perf/ui/browsers/hists.c b/tools/perf/ui/browsers/hists.c
> index 482f051..413bd62 100644
> --- a/tools/perf/ui/browsers/hists.c
> +++ b/tools/perf/ui/browsers/hists.c
> @@ -978,8 +978,8 @@ static int hist_browser__dump(struct hist_browser *browser)
>  	fp = fopen(filename, "w");
>  	if (fp == NULL) {
>  		char bf[64];
> -		strerror_r(errno, bf, sizeof(bf));
> -		ui_helpline__fpush("Couldn't write to %s: %s", filename, bf);
> +		const char *err = strerror_r(errno, bf, sizeof(bf));
> +		ui_helpline__fpush("Couldn't write to %s: %s", filename, err);
>  		return -1;
>  	}
>  
> diff --git a/tools/perf/util/target.c b/tools/perf/util/target.c
> index 1064d5b..3f59c49 100644
> --- a/tools/perf/util/target.c
> +++ b/tools/perf/util/target.c
> @@ -110,8 +110,17 @@ int perf_target__strerror(struct perf_target *target, int errnum,
>  	int idx;
>  	const char *msg;
>  
> +	BUG_ON(buflen > 0);
> +

No! It should be

  	BUG_ON(buflen == 0);

Thanks,
Namhyung


>  	if (errnum >= 0) {
> -		strerror_r(errnum, buf, buflen);
> +		const char *err = strerror_r(errnum, buf, buflen);
> +
> +		if (err != buf) {
> +			size_t len = strlen(err);
> +			char *c = mempcpy(buf, err, min(buflen - 1, len));
> +			*c = '\0';
> +		}
> +
>  		return 0;
>  	}

[PATCH] perf target: Fix check on buffer size

[Namhyung Kim]

From: Namhyung Kim <namhyung.kim@lge.com>

It was a mistake just replace assert to BUG_ON since its condition
should be negated. Fix it.

Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Ulrich Drepper <drepper@gmail.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
 tools/perf/util/target.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/util/target.c b/tools/perf/util/target.c
index 3f59c496e64c..051eaa68095e 100644
--- a/tools/perf/util/target.c
+++ b/tools/perf/util/target.c
@@ -110,7 +110,7 @@ int perf_target__strerror(struct perf_target *target, int errnum,
 	int idx;
 	const char *msg;
 
-	BUG_ON(buflen > 0);
+	BUG_ON(buflen == 0);
 
 	if (errnum >= 0) {
 		const char *err = strerror_r(errnum, buf, buflen);
-- 
1.7.10.4

[tip:perf/urgent] perf target: Fix check on buffer size

[tip-bot for Namhyung Kim]

Commit-ID:  0ecf4f0c02b7802de5d1251e03e6eab360f158e1
Gitweb:     http://git.kernel.org/tip/0ecf4f0c02b7802de5d1251e03e6eab360f158e1
Author:     Namhyung Kim <namhyung.kim@lge.com>
AuthorDate: Thu, 26 Jul 2012 10:50:10 +0900
Committer:  Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Wed, 1 Aug 2012 18:42:54 -0300

perf target: Fix check on buffer size

It was a mistake just replace assert to BUG_ON since its condition
should be negated. Fix it.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ulrich Drepper <drepper@gmail.com>
Link: http://lkml.kernel.org/r/1343267410-7758-1-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/util/target.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/tools/perf/util/target.c b/tools/perf/util/target.c
index 3f59c49..051eaa6 100644
--- a/tools/perf/util/target.c
+++ b/tools/perf/util/target.c
@@ -110,7 +110,7 @@ int perf_target__strerror(struct perf_target *target, int errnum,
 	int idx;
 	const char *msg;
 
-	BUG_ON(buflen > 0);
+	BUG_ON(buflen == 0);
 
 	if (errnum >= 0) {
 		const char *err = strerror_r(errnum, buf, buflen);