This is a note to let you know that I've just added the patch titled
perf stat: Fix bug in handling events in error state
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
perf-stat-fix-bug-in-handling-events-in-error-state.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From foo@baz Sun Mar 18 16:55:33 CET 2018
From: Stephane Eranian <eranian(a)google.com>
Date: Wed, 12 Apr 2017 11:23:01 -0700
Subject: perf stat: Fix bug in handling events in error state
From: Stephane Eranian <eranian(a)google.com>
[ Upstream commit db49a71798a38f3ddf3f3462703328dca39b1ac7 ]
(This is a patch has been sitting in the Intel CQM/CMT driver series for
a while, despite not depend on it. Sending it now independently since
the series is being discarded.)
When an event is in error state, read() returns 0 instead of sizeof()
buffer. In certain modes, such as interval printing, ignoring the 0
return value may cause bogus count deltas to be computed and thus
invalid results printed.
This patch fixes this problem by modifying read_counters() to mark the
event as not scaled (scaled = -1) to force the printout routine to show
<NOT COUNTED>.
Signed-off-by: Stephane Eranian <eranian(a)google.com>
Reviewed-by: David Carrillo-Cisneros <davidcc(a)google.com>
Acked-by: Jiri Olsa <jolsa(a)redhat.com>
Cc: Adrian Hunter <adrian.hunter(a)intel.com>
Cc: Alexander Shishkin <alexander.shishkin(a)linux.intel.com>
Cc: Andi Kleen <ak(a)linux.intel.com>
Cc: Mathieu Poirier <mathieu.poirier(a)linaro.org>
Cc: Paul Turner <pjt(a)google.com>
Cc: Peter Zijlstra <peterz(a)infradead.org>
Cc: Wang Nan <wangnan0(a)huawei.com>
Link: http://lkml.kernel.org/r/20170412182301.44406-1-davidcc@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme(a)redhat.com>
Signed-off-by: Sasha Levin <alexander.levin(a)microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
tools/perf/builtin-stat.c | 12 +++++++++---
tools/perf/util/evsel.c | 4 ++--
2 files changed, 11 insertions(+), 5 deletions(-)
--- a/tools/perf/builtin-stat.c
+++ b/tools/perf/builtin-stat.c
@@ -311,8 +311,12 @@ static int read_counter(struct perf_evse
struct perf_counts_values *count;
count = perf_counts(counter->counts, cpu, thread);
- if (perf_evsel__read(counter, cpu, thread, count))
+ if (perf_evsel__read(counter, cpu, thread, count)) {
+ counter->counts->scaled = -1;
+ perf_counts(counter->counts, cpu, thread)->ena = 0;
+ perf_counts(counter->counts, cpu, thread)->run = 0;
return -1;
+ }
if (STAT_RECORD) {
if (perf_evsel__write_stat_event(counter, cpu, thread, count)) {
@@ -337,12 +341,14 @@ static int read_counter(struct perf_evse
static void read_counters(void)
{
struct perf_evsel *counter;
+ int ret;
evlist__for_each_entry(evsel_list, counter) {
- if (read_counter(counter))
+ ret = read_counter(counter);
+ if (ret)
pr_debug("failed to read counter %s\n", counter->name);
- if (perf_stat_process_counter(&stat_config, counter))
+ if (ret == 0 && perf_stat_process_counter(&stat_config, counter))
pr_warning("failed to process counter %s\n", counter->name);
}
}
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -1221,7 +1221,7 @@ int perf_evsel__read(struct perf_evsel *
if (FD(evsel, cpu, thread) < 0)
return -EINVAL;
- if (readn(FD(evsel, cpu, thread), count, sizeof(*count)) < 0)
+ if (readn(FD(evsel, cpu, thread), count, sizeof(*count)) <= 0)
return -errno;
return 0;
@@ -1239,7 +1239,7 @@ int __perf_evsel__read_on_cpu(struct per
if (evsel->counts == NULL && perf_evsel__alloc_counts(evsel, cpu + 1, thread + 1) < 0)
return -ENOMEM;
- if (readn(FD(evsel, cpu, thread), &count, nv * sizeof(u64)) < 0)
+ if (readn(FD(evsel, cpu, thread), &count, nv * sizeof(u64)) <= 0)
return -errno;
perf_evsel__compute_deltas(evsel, cpu, thread, &count);
Patches currently in stable-queue which might be from eranian(a)google.com are
queue-4.9/perf-session-don-t-rely-on-evlist-in-pipe-mode.patch
queue-4.9/perf-tools-make-perf_event__synthesize_mmap_events-scale.patch
queue-4.9/perf-inject-copy-events-when-reordering-events-in-pipe-mode.patch
queue-4.9/perf-stat-fix-bug-in-handling-events-in-error-state.patch
This is a note to let you know that I've just added the patch titled
perf sort: Fix segfault with basic block 'cycles' sort dimension
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
perf-sort-fix-segfault-with-basic-block-cycles-sort-dimension.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From foo@baz Sun Mar 18 16:55:33 CET 2018
From: Changbin Du <changbin.du(a)intel.com>
Date: Mon, 13 Mar 2017 16:31:48 +0800
Subject: perf sort: Fix segfault with basic block 'cycles' sort dimension
From: Changbin Du <changbin.du(a)intel.com>
[ Upstream commit 4b0b3aa6a2756e6115fdf275c521e4552a7082f3 ]
Skip the sample which doesn't have branch_info to avoid segmentation
fault:
The fault can be reproduced by:
perf record -a
perf report -F cycles
Signed-off-by: Changbin Du <changbin.du(a)intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme(a)redhat.com>
Cc: Andi Kleen <ak(a)linux.intel.com>
Cc: Peter Zijlstra <peterz(a)infradead.org>
Fixes: 0e332f033a82 ("perf tools: Add support for cycles, weight branch_info field")
Link: http://lkml.kernel.org/r/20170313083148.23568-1-changbin.du@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme(a)redhat.com>
Signed-off-by: Sasha Levin <alexander.levin(a)microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
tools/perf/util/sort.c | 5 +++++
1 file changed, 5 insertions(+)
--- a/tools/perf/util/sort.c
+++ b/tools/perf/util/sort.c
@@ -846,6 +846,9 @@ static int hist_entry__mispredict_snprin
static int64_t
sort__cycles_cmp(struct hist_entry *left, struct hist_entry *right)
{
+ if (!left->branch_info || !right->branch_info)
+ return cmp_null(left->branch_info, right->branch_info);
+
return left->branch_info->flags.cycles -
right->branch_info->flags.cycles;
}
@@ -853,6 +856,8 @@ sort__cycles_cmp(struct hist_entry *left
static int hist_entry__cycles_snprintf(struct hist_entry *he, char *bf,
size_t size, unsigned int width)
{
+ if (!he->branch_info)
+ return scnprintf(bf, size, "%-.*s", width, "N/A");
if (he->branch_info->flags.cycles == 0)
return repsep_snprintf(bf, size, "%-*s", width, "-");
return repsep_snprintf(bf, size, "%-*hd", width,
Patches currently in stable-queue which might be from changbin.du(a)intel.com are
queue-4.9/perf-sort-fix-segfault-with-basic-block-cycles-sort-dimension.patch
This is a note to let you know that I've just added the patch titled
perf session: Don't rely on evlist in pipe mode
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
perf-session-don-t-rely-on-evlist-in-pipe-mode.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From foo@baz Sun Mar 18 16:55:33 CET 2018
From: David Carrillo-Cisneros <davidcc(a)google.com>
Date: Mon, 10 Apr 2017 13:14:30 -0700
Subject: perf session: Don't rely on evlist in pipe mode
From: David Carrillo-Cisneros <davidcc(a)google.com>
[ Upstream commit 0973ad97c187e06aece61f685b9c3b2d93290a73 ]
Session sets a number parameters that rely on evlist. These parameters
are not used in pipe-mode and should not be set, since evlist is
unavailable. Fix that.
Signed-off-by: David Carrillo-Cisneros <davidcc(a)google.com>
Acked-by: Jiri Olsa <jolsa(a)kernel.org>
Cc: Alexander Shishkin <alexander.shishkin(a)linux.intel.com>
Cc: Andi Kleen <ak(a)linux.intel.com>
Cc: He Kuang <hekuang(a)huawei.com>
Cc: Masami Hiramatsu <mhiramat(a)kernel.org>
Cc: Paul Turner <pjt(a)google.com>
Cc: Peter Zijlstra <peterz(a)infradead.org>
Cc: Simon Que <sque(a)chromium.org>
Cc: Stephane Eranian <eranian(a)google.com>
Cc: Wang Nan <wangnan0(a)huawei.com>
Link: http://lkml.kernel.org/r/20170410201432.24807-6-davidcc@google.com
[ Check if file != NULL in perf_session__new(), like when used by builtin-top.c ]
Signed-off-by: Arnaldo Carvalho de Melo <acme(a)redhat.com>
Signed-off-by: Sasha Levin <alexander.levin(a)microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
tools/perf/util/session.c | 16 +++++++++++++---
1 file changed, 13 insertions(+), 3 deletions(-)
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -139,8 +139,14 @@ struct perf_session *perf_session__new(s
if (perf_session__open(session) < 0)
goto out_close;
- perf_session__set_id_hdr_size(session);
- perf_session__set_comm_exec(session);
+ /*
+ * set session attributes that are present in perf.data
+ * but not in pipe-mode.
+ */
+ if (!file->is_pipe) {
+ perf_session__set_id_hdr_size(session);
+ perf_session__set_comm_exec(session);
+ }
}
} else {
session->machines.host.env = &perf_env;
@@ -155,7 +161,11 @@ struct perf_session *perf_session__new(s
pr_warning("Cannot read kernel map\n");
}
- if (tool && tool->ordering_requires_timestamps &&
+ /*
+ * In pipe-mode, evlist is empty until PERF_RECORD_HEADER_ATTR is
+ * processed, so perf_evlist__sample_id_all is not meaningful here.
+ */
+ if ((!file || !file->is_pipe) && tool && tool->ordering_requires_timestamps &&
tool->ordered_events && !perf_evlist__sample_id_all(session->evlist)) {
dump_printf("WARNING: No sample_id_all support, falling back to unordered processing\n");
tool->ordered_events = false;
Patches currently in stable-queue which might be from davidcc(a)google.com are
queue-4.9/perf-session-don-t-rely-on-evlist-in-pipe-mode.patch
queue-4.9/perf-inject-copy-events-when-reordering-events-in-pipe-mode.patch
queue-4.9/perf-stat-fix-bug-in-handling-events-in-error-state.patch
This is a note to let you know that I've just added the patch titled
perf probe: Return errno when not hitting any event
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
perf-probe-return-errno-when-not-hitting-any-event.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From foo@baz Sun Mar 18 16:55:33 CET 2018
From: Kefeng Wang <wangkefeng.wang(a)huawei.com>
Date: Fri, 17 Mar 2017 16:16:32 +0800
Subject: perf probe: Return errno when not hitting any event
From: Kefeng Wang <wangkefeng.wang(a)huawei.com>
[ Upstream commit 70946723eeb859466f026274b29c6196e39149c4 ]
On old perf, when using 'perf probe -d' to delete an inexistent event,
it returns errno, eg,
-bash-4.3# perf probe -d xxx || echo $?
Info: Event "*:xxx" does not exist.
Error: Failed to delete events.
255
But now perf_del_probe_events() will always set ret = 0, different from
previous del_perf_probe_events(). After this, it returns errno again,
eg,
-bash-4.3# ./perf probe -d xxx || echo $?
"xxx" does not hit any event.
Error: Failed to delete events.
254
And it is more appropriate to return -ENOENT instead of -EPERM.
Signed-off-by: Kefeng Wang <wangkefeng.wang(a)huawei.com>
Acked-by: Masami Hiramatsu <mhiramat(a)kernel.org>
Cc: Hanjun Guo <guohanjun(a)huawei.com>
Cc: Jiri Olsa <jolsa(a)kernel.org>
Cc: Peter Zijlstra <peterz(a)infradead.org>
Cc: Wang Nan <wangnan0(a)huawei.com>
Fixes: dddc7ee32fa1 ("perf probe: Fix an error when deleting probes successfully")
Link: http://lkml.kernel.org/r/1489738592-61011-1-git-send-email-wangkefeng.wang@…
Signed-off-by: Arnaldo Carvalho de Melo <acme(a)redhat.com>
Signed-off-by: Sasha Levin <alexander.levin(a)microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
tools/perf/builtin-probe.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
--- a/tools/perf/builtin-probe.c
+++ b/tools/perf/builtin-probe.c
@@ -442,9 +442,9 @@ static int perf_del_probe_events(struct
}
if (ret == -ENOENT && ret2 == -ENOENT)
- pr_debug("\"%s\" does not hit any event.\n", str);
- /* Note that this is silently ignored */
- ret = 0;
+ pr_warning("\"%s\" does not hit any event.\n", str);
+ else
+ ret = 0;
error:
if (kfd >= 0)
Patches currently in stable-queue which might be from wangkefeng.wang(a)huawei.com are
queue-4.9/perf-probe-return-errno-when-not-hitting-any-event.patch
This is a note to let you know that I've just added the patch titled
perf probe: Fix concat_probe_trace_events
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
perf-probe-fix-concat_probe_trace_events.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From foo@baz Sun Mar 18 16:55:33 CET 2018
From: Ravi Bangoria <ravi.bangoria(a)linux.vnet.ibm.com>
Date: Wed, 8 Mar 2017 12:29:07 +0530
Subject: perf probe: Fix concat_probe_trace_events
From: Ravi Bangoria <ravi.bangoria(a)linux.vnet.ibm.com>
[ Upstream commit f0a30dca5f84fe8048271799b56677ac2279de66 ]
'*ntevs' contains number of elements present in 'tevs' array. If there
are no elements in array, 'tevs2' can be directly assigned to 'tevs'
without allocating more space. So the condition should be '*ntevs == 0'
not 'ntevs == 0'.
Signed-off-by: Ravi Bangoria <ravi.bangoria(a)linux.vnet.ibm.com>
Acked-by: Masami Hiramatsu <mhiramat(a)kernel.org>
Cc: Alexander Shishkin <alexander.shishkin(a)linux.intel.com>
Cc: Peter Zijlstra <peterz(a)infradead.org>
Fixes: 42bba263eb58 ("perf probe: Allow wildcard for cached events")
Link: http://lkml.kernel.org/r/20170308065908.4128-1-ravi.bangoria@linux.vnet.ibm…
Signed-off-by: Arnaldo Carvalho de Melo <acme(a)redhat.com>
Signed-off-by: Sasha Levin <alexander.levin(a)microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
tools/perf/util/probe-event.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -3060,7 +3060,7 @@ concat_probe_trace_events(struct probe_t
struct probe_trace_event *new_tevs;
int ret = 0;
- if (ntevs == 0) {
+ if (*ntevs == 0) {
*tevs = *tevs2;
*ntevs = ntevs2;
*tevs2 = NULL;
Patches currently in stable-queue which might be from ravi.bangoria(a)linux.vnet.ibm.com are
queue-4.9/perf-probe-fix-concat_probe_trace_events.patch
This is a note to let you know that I've just added the patch titled
perf inject: Copy events when reordering events in pipe mode
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
perf-inject-copy-events-when-reordering-events-in-pipe-mode.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From foo@baz Sun Mar 18 16:55:33 CET 2018
From: David Carrillo-Cisneros <davidcc(a)google.com>
Date: Mon, 10 Apr 2017 13:14:27 -0700
Subject: perf inject: Copy events when reordering events in pipe mode
From: David Carrillo-Cisneros <davidcc(a)google.com>
[ Upstream commit 1e0d4f0200e4dbdfc38d818f329d8a0955f7c6f5 ]
__perf_session__process_pipe_events reuses the same memory buffer to
process all events in the pipe.
When reordering is needed (e.g. -b option), events are not immediately
flushed, but kept around until reordering is possible, causing
memory corruption.
The problem is usually observed by a "Unknown sample error" output. It
can easily be reproduced by:
perf record -o - noploop | perf inject -b > output
Committer testing:
Before:
$ perf record -o - stress -t 2 -c 2 | perf inject -b > /dev/null
stress: info: [8297] dispatching hogs: 2 cpu, 0 io, 0 vm, 0 hdd
stress: info: [8297] successful run completed in 2s
[ perf record: Woken up 3 times to write data ]
[ perf record: Captured and wrote 0.000 MB - ]
Warning:
Found 1 unknown events!
Is this an older tool processing a perf.data file generated by a more recent tool?
If that is not the case, consider reporting to linux-kernel(a)vger.kernel.org.
$
After:
$ perf record -o - stress -t 2 -c 2 | perf inject -b > /dev/null
stress: info: [9027] dispatching hogs: 2 cpu, 0 io, 0 vm, 0 hdd
stress: info: [9027] successful run completed in 2s
[ perf record: Woken up 3 times to write data ]
[ perf record: Captured and wrote 0.000 MB - ]
no symbols found in /usr/bin/stress, maybe install a debug package?
no symbols found in /usr/bin/stress, maybe install a debug package?
$
Signed-off-by: David Carrillo-Cisneros <davidcc(a)google.com>
Tested-by: Arnaldo Carvalho de Melo <acme(a)redhat.com>
Acked-by: Jiri Olsa <jolsa(a)kernel.org>
Cc: Alexander Shishkin <alexander.shishkin(a)linux.intel.com>
Cc: Andi Kleen <ak(a)linux.intel.com>
Cc: He Kuang <hekuang(a)huawei.com>
Cc: Masami Hiramatsu <mhiramat(a)kernel.org>
Cc: Paul Turner <pjt(a)google.com>
Cc: Peter Zijlstra <peterz(a)infradead.org>
Cc: Simon Que <sque(a)chromium.org>
Cc: Stephane Eranian <eranian(a)google.com>
Cc: Wang Nan <wangnan0(a)huawei.com>
Link: http://lkml.kernel.org/r/20170410201432.24807-3-davidcc@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme(a)redhat.com>
Signed-off-by: Sasha Levin <alexander.levin(a)microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
tools/perf/util/ordered-events.c | 3 ++-
tools/perf/util/session.c | 1 +
2 files changed, 3 insertions(+), 1 deletion(-)
--- a/tools/perf/util/ordered-events.c
+++ b/tools/perf/util/ordered-events.c
@@ -79,7 +79,7 @@ static union perf_event *dup_event(struc
static void free_dup_event(struct ordered_events *oe, union perf_event *event)
{
- if (oe->copy_on_queue) {
+ if (event && oe->copy_on_queue) {
oe->cur_alloc_size -= event->header.size;
free(event);
}
@@ -150,6 +150,7 @@ void ordered_events__delete(struct order
list_move(&event->list, &oe->cache);
oe->nr_events--;
free_dup_event(oe, event->event);
+ event->event = NULL;
}
int ordered_events__queue(struct ordered_events *oe, union perf_event *event,
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -1628,6 +1628,7 @@ static int __perf_session__process_pipe_
buf = malloc(cur_size);
if (!buf)
return -errno;
+ ordered_events__set_copy_on_queue(oe, true);
more:
event = buf;
err = readn(fd, event, sizeof(struct perf_event_header));
Patches currently in stable-queue which might be from davidcc(a)google.com are
queue-4.9/perf-session-don-t-rely-on-evlist-in-pipe-mode.patch
queue-4.9/perf-inject-copy-events-when-reordering-events-in-pipe-mode.patch
queue-4.9/perf-stat-fix-bug-in-handling-events-in-error-state.patch
This is a note to let you know that I've just added the patch titled
perf evsel: Return exact sub event which failed with EPERM for wildcards
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
perf-evsel-return-exact-sub-event-which-failed-with-eperm-for-wildcards.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From foo@baz Sun Mar 18 16:55:33 CET 2018
From: Jin Yao <yao.jin(a)linux.intel.com>
Date: Fri, 7 Apr 2017 20:08:52 +0800
Subject: perf evsel: Return exact sub event which failed with EPERM for wildcards
From: Jin Yao <yao.jin(a)linux.intel.com>
[ Upstream commit 32ccb130f5325abc81b32b1a538390f46e4860f6 ]
The kernel has a special check for a specific irq_vectors trace event.
TRACE_EVENT_PERF_PERM(irq_work_exit,
is_sampling_event(p_event) ? -EPERM : 0);
The perf-record fails for this irq_vectors event when it is present,
like when using a wildcard:
root@skl:/tmp# perf record -a -e irq_vectors:* sleep 2
Error:
You may not have permission to collect system-wide stats.
Consider tweaking /proc/sys/kernel/perf_event_paranoid,
which controls use of the performance events system by
unprivileged users (without CAP_SYS_ADMIN).
The current value is 2:
-1: Allow use of (almost) all events by all users
>= 0: Disallow raw tracepoint access by users without CAP_IOC_LOCK
>= 1: Disallow CPU event access by users without CAP_SYS_ADMIN
>= 2: Disallow kernel profiling by users without CAP_SYS_ADMIN
To make this setting permanent, edit /etc/sysctl.conf too, e.g.:
kernel.perf_event_paranoid = -1
This patch prints out the exact sub event that failed with EPERM for
wildcards to help in understanding what went wrong when this event is
present:
After the patch:
root@skl:/tmp# perf record -a -e irq_vectors:* sleep 2
Error:
No permission to enable irq_vectors:irq_work_exit event.
You may not have permission to collect system-wide stats.
......
Committer notes:
So we have a lot of irq_vectors events:
[root@jouet ~]# perf list irq_vectors:*
List of pre-defined events (to be used in -e):
irq_vectors:call_function_entry [Tracepoint event]
irq_vectors:call_function_exit [Tracepoint event]
irq_vectors:call_function_single_entry [Tracepoint event]
irq_vectors:call_function_single_exit [Tracepoint event]
irq_vectors:deferred_error_apic_entry [Tracepoint event]
irq_vectors:deferred_error_apic_exit [Tracepoint event]
irq_vectors:error_apic_entry [Tracepoint event]
irq_vectors:error_apic_exit [Tracepoint event]
irq_vectors:irq_work_entry [Tracepoint event]
irq_vectors:irq_work_exit [Tracepoint event]
irq_vectors:local_timer_entry [Tracepoint event]
irq_vectors:local_timer_exit [Tracepoint event]
irq_vectors:reschedule_entry [Tracepoint event]
irq_vectors:reschedule_exit [Tracepoint event]
irq_vectors:spurious_apic_entry [Tracepoint event]
irq_vectors:spurious_apic_exit [Tracepoint event]
irq_vectors:thermal_apic_entry [Tracepoint event]
irq_vectors:thermal_apic_exit [Tracepoint event]
irq_vectors:threshold_apic_entry [Tracepoint event]
irq_vectors:threshold_apic_exit [Tracepoint event]
irq_vectors:x86_platform_ipi_entry [Tracepoint event]
irq_vectors:x86_platform_ipi_exit [Tracepoint event]
#
And some may be sampled:
[root@jouet ~]# perf record -e irq_vectors:local* sleep 20s
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.020 MB perf.data (2 samples) ]
[root@jouet ~]# perf report -D | egrep 'stats:|events:'
Aggregated stats:
TOTAL events: 155
MMAP events: 144
COMM events: 2
EXIT events: 1
SAMPLE events: 2
MMAP2 events: 4
FINISHED_ROUND events: 1
TIME_CONV events: 1
irq_vectors:local_timer_entry stats:
TOTAL events: 1
SAMPLE events: 1
irq_vectors:local_timer_exit stats:
TOTAL events: 1
SAMPLE events: 1
[root@jouet ~]#
But, as shown in the tracepoint definition at the start of this message,
some, like "irq_vectors:irq_work_exit", may not be sampled, just counted,
i.e. if we try to sample, as when using 'perf record', we get an error:
[root@jouet ~]# perf record -e irq_vectors:irq_work_exit
Error:
You may not have permission to collect system-wide stats.
Consider tweaking /proc/sys/kernel/perf_event_paranoid,
<SNIP>
The error message is misleading, this patch will help in pointing out
what is the event causing such an error, but the error message needs
improvement, i.e. we need to figure out a way to check if a tracepoint
is counting only, like this one, when all we can do is to count it with
'perf stat', at most printing the delta using interval printing, as in:
[root@jouet ~]# perf stat -I 5000 -e irq_vectors:irq_work_*
# time counts unit events
5.000168871 0 irq_vectors:irq_work_entry
5.000168871 0 irq_vectors:irq_work_exit
10.000676730 0 irq_vectors:irq_work_entry
10.000676730 0 irq_vectors:irq_work_exit
15.001122415 0 irq_vectors:irq_work_entry
15.001122415 0 irq_vectors:irq_work_exit
20.001298051 0 irq_vectors:irq_work_entry
20.001298051 0 irq_vectors:irq_work_exit
25.001485020 1 irq_vectors:irq_work_entry
25.001485020 1 irq_vectors:irq_work_exit
30.001658706 0 irq_vectors:irq_work_entry
30.001658706 0 irq_vectors:irq_work_exit
^C 32.045711878 0 irq_vectors:irq_work_entry
32.045711878 0 irq_vectors:irq_work_exit
[root@jouet ~]#
But at least, when we use a wildcard, this patch helps a bit.
Signed-off-by: Yao Jin <yao.jin(a)linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme(a)redhat.com>
Cc: Alexander Shishkin <alexander.shishkin(a)linux.intel.com>
Cc: Andi Kleen <ak(a)linux.intel.com>
Cc: Jiri Olsa <jolsa(a)kernel.org>
Cc: Kan Liang <kan.liang(a)intel.com>
Cc: Peter Zijlstra <peterz(a)infradead.org>
Link: http://lkml.kernel.org/r/1491566932-503-1-git-send-email-yao.jin@linux.inte…
Signed-off-by: Arnaldo Carvalho de Melo <acme(a)redhat.com>
Signed-off-by: Sasha Levin <alexander.levin(a)microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
tools/perf/util/evsel.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -2400,11 +2400,17 @@ int perf_evsel__open_strerror(struct per
int err, char *msg, size_t size)
{
char sbuf[STRERR_BUFSIZE];
+ int printed = 0;
switch (err) {
case EPERM:
case EACCES:
- return scnprintf(msg, size,
+ if (err == EPERM)
+ printed = scnprintf(msg, size,
+ "No permission to enable %s event.\n\n",
+ perf_evsel__name(evsel));
+
+ return scnprintf(msg + printed, size - printed,
"You may not have permission to collect %sstats.\n\n"
"Consider tweaking /proc/sys/kernel/perf_event_paranoid,\n"
"which controls use of the performance events system by\n"
Patches currently in stable-queue which might be from yao.jin(a)linux.intel.com are
queue-4.9/perf-evsel-return-exact-sub-event-which-failed-with-eperm-for-wildcards.patch
This is a note to let you know that I've just added the patch titled
perf buildid: Do not assume that readlink() returns a null terminated string
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
perf-buildid-do-not-assume-that-readlink-returns-a-null-terminated-string.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From foo@baz Sun Mar 18 16:55:33 CET 2018
From: Tommi Rantala <tommi.t.rantala(a)nokia.com>
Date: Wed, 22 Mar 2017 15:06:20 +0200
Subject: perf buildid: Do not assume that readlink() returns a null terminated string
From: Tommi Rantala <tommi.t.rantala(a)nokia.com>
[ Upstream commit 5a2342111c68e623e27ee7ea3d0492d8dad6bda0 ]
Valgrind was complaining:
$ valgrind ./perf list >/dev/null
==11643== Memcheck, a memory error detector
==11643== Copyright (C) 2002-2015, and GNU GPL'd, by Julian Seward et al.
==11643== Using Valgrind-3.12.0 and LibVEX; rerun with -h for copyright info
==11643== Command: ./perf list
==11643==
==11643== Conditional jump or move depends on uninitialised value(s)
==11643== at 0x4C30620: rindex (vg_replace_strmem.c:199)
==11643== by 0x49DAA9: build_id_cache__origname (build-id.c:198)
==11643== by 0x49E1C7: build_id_cache__valid_id (build-id.c:222)
==11643== by 0x49E1C7: build_id_cache__list_all (build-id.c:507)
==11643== by 0x4B9C8F: print_sdt_events (parse-events.c:2067)
==11643== by 0x4BB0B3: print_events (parse-events.c:2313)
==11643== by 0x439501: cmd_list (builtin-list.c:53)
==11643== by 0x497150: run_builtin (perf.c:359)
==11643== by 0x428CE0: handle_internal_command (perf.c:421)
==11643== by 0x428CE0: run_argv (perf.c:467)
==11643== by 0x428CE0: main (perf.c:614)
[...]
Additionally, a zero length result from readlink() is not very interesting.
Signed-off-by: Tommi Rantala <tommi.t.rantala(a)nokia.com>
Cc: Alexander Shishkin <alexander.shishkin(a)linux.intel.com>
Cc: Peter Zijlstra <peterz(a)infradead.org>
Link: http://lkml.kernel.org/r/20170322130624.21881-3-tommi.t.rantala@nokia.com
Signed-off-by: Arnaldo Carvalho de Melo <acme(a)redhat.com>
Signed-off-by: Sasha Levin <alexander.levin(a)microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
tools/perf/util/build-id.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
--- a/tools/perf/util/build-id.c
+++ b/tools/perf/util/build-id.c
@@ -182,13 +182,17 @@ char *build_id_cache__origname(const cha
char buf[PATH_MAX];
char *ret = NULL, *p;
size_t offs = 5; /* == strlen("../..") */
+ ssize_t len;
linkname = build_id_cache__linkname(sbuild_id, NULL, 0);
if (!linkname)
return NULL;
- if (readlink(linkname, buf, PATH_MAX) < 0)
+ len = readlink(linkname, buf, sizeof(buf) - 1);
+ if (len <= 0)
goto out;
+ buf[len] = '\0';
+
/* The link should be "../..<origpath>/<sbuild_id>" */
p = strrchr(buf, '/'); /* Cut off the "/<sbuild_id>" */
if (p && (p > buf + offs)) {
Patches currently in stable-queue which might be from tommi.t.rantala(a)nokia.com are
queue-4.9/perf-buildid-do-not-assume-that-readlink-returns-a-null-terminated-string.patch
This is a note to let you know that I've just added the patch titled
perf annotate: Fix a bug following symbolic link of a build-id file
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
perf-annotate-fix-a-bug-following-symbolic-link-of-a-build-id-file.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From foo@baz Sun Mar 18 16:55:33 CET 2018
From: Taeung Song <treeze.taeung(a)gmail.com>
Date: Mon, 27 Mar 2017 16:10:36 +0900
Subject: perf annotate: Fix a bug following symbolic link of a build-id file
From: Taeung Song <treeze.taeung(a)gmail.com>
[ Upstream commit 6ebd2547dd24daf95a21b2bc59931de8502afcc3 ]
It is wrong way to read link name from a build-id file. Because a
build-id file is not anymore a symbolic link but build-id directory of
it is symbolic link, so fix it.
For example, if build-id file name gotten from
dso__build_id_filename() is as below,
/root/.debug/.build-id/4f/75c7d197c951659d1c1b8b5fd49bcdf8f3f8b1/elf
To correctly read link name of build-id, use the build-id dir path that
is a symbolic link, instead of the above build-id file name like below.
/root/.debug/.build-id/4f/75c7d197c951659d1c1b8b5fd49bcdf8f3f8b1
Signed-off-by: Taeung Song <treeze.taeung(a)gmail.com>
Cc: Jiri Olsa <jolsa(a)redhat.com>
Cc: Masami Hiramatsu <mhiramat(a)kernel.org>
Cc: Namhyung Kim <namhyung(a)kernel.org>
Cc: Peter Zijlstra <peterz(a)infradead.org>
Cc: Wang Nan <wangnan0(a)huawei.com>
Link: http://lkml.kernel.org/r/1490598638-13947-2-git-send-email-treeze.taeung@gm…
Fixes: 01412261d994 ("perf buildid-cache: Use path/to/bin/buildid/elf instead of path/to/bin/buildid")
Signed-off-by: Arnaldo Carvalho de Melo <acme(a)redhat.com>
Signed-off-by: Sasha Levin <alexander.levin(a)microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
tools/perf/util/annotate.c | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)
--- a/tools/perf/util/annotate.c
+++ b/tools/perf/util/annotate.c
@@ -1250,6 +1250,7 @@ static int dso__disassemble_filename(str
{
char linkname[PATH_MAX];
char *build_id_filename;
+ char *build_id_path = NULL;
if (dso->symtab_type == DSO_BINARY_TYPE__KALLSYMS &&
!dso__is_kcore(dso))
@@ -1265,8 +1266,14 @@ static int dso__disassemble_filename(str
goto fallback;
}
+ build_id_path = strdup(filename);
+ if (!build_id_path)
+ return -1;
+
+ dirname(build_id_path);
+
if (dso__is_kcore(dso) ||
- readlink(filename, linkname, sizeof(linkname)) < 0 ||
+ readlink(build_id_path, linkname, sizeof(linkname)) < 0 ||
strstr(linkname, DSO__NAME_KALLSYMS) ||
access(filename, R_OK)) {
fallback:
@@ -1278,6 +1285,7 @@ fallback:
__symbol__join_symfs(filename, filename_size, dso->long_name);
}
+ free(build_id_path);
return 0;
}
Patches currently in stable-queue which might be from treeze.taeung(a)gmail.com are
queue-4.9/perf-annotate-fix-a-bug-following-symbolic-link-of-a-build-id-file.patch
This is a note to let you know that I've just added the patch titled
PCI/MSI: Stop disabling MSI/MSI-X in pci_device_shutdown()
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
pci-msi-stop-disabling-msi-msi-x-in-pci_device_shutdown.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From foo@baz Sun Mar 18 16:55:33 CET 2018
From: Prarit Bhargava <prarit(a)redhat.com>
Date: Thu, 26 Jan 2017 14:07:47 -0500
Subject: PCI/MSI: Stop disabling MSI/MSI-X in pci_device_shutdown()
From: Prarit Bhargava <prarit(a)redhat.com>
[ Upstream commit fda78d7a0ead144f4b2cdb582dcba47911f4952c ]
The pci_bus_type .shutdown method, pci_device_shutdown(), is called from
device_shutdown() in the kernel restart and shutdown paths.
Previously, pci_device_shutdown() called pci_msi_shutdown() and
pci_msix_shutdown(). This disables MSI and MSI-X, which causes the device
to fall back to raising interrupts via INTx. But the driver is still bound
to the device, it doesn't know about this change, and it likely doesn't
have an INTx handler, so these INTx interrupts cause "nobody cared"
warnings like this:
irq 16: nobody cared (try booting with the "irqpoll" option)
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.8.2-1.el7_UNSUPPORTED.x86_64 #1
Hardware name: Hewlett-Packard HP Z820 Workstation/158B, BIOS J63 v03.90 06/
...
The MSI disabling code was added by d52877c7b1af ("pci/irq: let
pci_device_shutdown to call pci_msi_shutdown v2") because a driver left MSI
enabled and kdump failed because the kexeced kernel wasn't prepared to
receive the MSI interrupts.
Subsequent commits 1851617cd2da ("PCI/MSI: Disable MSI at enumeration even
if kernel doesn't support MSI") and e80e7edc55ba ("PCI/MSI: Initialize MSI
capability for all architectures") changed the kexeced kernel to disable
all MSIs itself so it no longer depends on the crashed kernel to clean up
after itself.
Stop disabling MSI/MSI-X in pci_device_shutdown(). This resolves the
"nobody cared" unhandled IRQ issue above. It also allows PCI serial
devices, which may rely on the MSI interrupts, to continue outputting
messages during reboot/shutdown.
[bhelgaas: changelog, drop pci_msi_shutdown() and pci_msix_shutdown() calls
altogether]
Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=187351
Signed-off-by: Prarit Bhargava <prarit(a)redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas(a)google.com>
CC: Alex Williamson <alex.williamson(a)redhat.com>
CC: David Arcari <darcari(a)redhat.com>
CC: Myron Stowe <mstowe(a)redhat.com>
CC: Lukas Wunner <lukas(a)wunner.de>
CC: Keith Busch <keith.busch(a)intel.com>
CC: Mika Westerberg <mika.westerberg(a)linux.intel.com>
Signed-off-by: Sasha Levin <alexander.levin(a)microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
drivers/pci/pci-driver.c | 2 --
1 file changed, 2 deletions(-)
--- a/drivers/pci/pci-driver.c
+++ b/drivers/pci/pci-driver.c
@@ -463,8 +463,6 @@ static void pci_device_shutdown(struct d
if (drv && drv->shutdown)
drv->shutdown(pci_dev);
- pci_msi_shutdown(pci_dev);
- pci_msix_shutdown(pci_dev);
/*
* If this is a kexec reboot, turn off Bus Master bit on the
Patches currently in stable-queue which might be from prarit(a)redhat.com are
queue-4.9/pci-msi-stop-disabling-msi-msi-x-in-pci_device_shutdown.patch