* [PATCH] perf tool sort: Use default sort if evlist is empty
@ 2017-07-21 5:11 David Carrillo-Cisneros
2017-07-21 7:44 ` Jiri Olsa
2017-07-26 20:03 ` Arnaldo Carvalho de Melo
0 siblings, 2 replies; 7+ messages in thread
From: David Carrillo-Cisneros @ 2017-07-21 5:11 UTC (permalink / raw)
To: linux-kernel
Cc: Ingo Molnar, Arnaldo Carvalho de Melo, Alexander Shishkin,
Andi Kleen, Simon Que, Wang Nan, Jiri Olsa, Namhyung Kim,
Stephane Eranian, Paul Turner, David Carrillo-Cisneros
Fixes bug noted by Jiri in https://lkml.org/lkml/2017/6/13/755 and caused
by commit d49dadea7862 ("perf tools: Make 'trace' or 'trace_fields' sort
key default for tracepoint events")
not taking into account that evlist is empty in pipe-mode.
Before this commit, pipe mode will only show bogus "100.00% N/A" instead
of correct output as follows:
$ perf record -o - sleep 1 | perf report -i -
# To display the perf.data header info, please use --header/--header-only options.
#
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.000 MB - ]
#
# Total Lost Samples: 0
#
# Samples: 8 of event 'cycles:ppH'
# Event count (approx.): 145658
#
# Overhead Trace output
# ........ ............
#
100.00% N/A
Correct output, after patch:
$ perf record -o - sleep 1 | perf report -i -
# To display the perf.data header info, please use --header/--header-only options.
#
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.000 MB - ]
#
# Total Lost Samples: 0
#
# Samples: 8 of event 'cycles:ppH'
# Event count (approx.): 191331
#
# Overhead Command Shared Object Symbol
# ........ ....... ................. .................................
#
81.63% sleep libc-2.19.so [.] _exit
13.58% sleep ld-2.19.so [.] do_lookup_x
2.34% sleep [kernel.kallsyms] [k] context_switch
2.34% sleep libc-2.19.so [.] __GI___libc_nanosleep
0.11% perf [kernel.kallsyms] [k] __intel_pmu_enable_a
Signed-off-by: David Carrillo-Cisneros <davidcc@google.com>
---
tools/perf/util/evlist.h | 5 +++++
tools/perf/util/sort.c | 2 +-
2 files changed, 6 insertions(+), 1 deletion(-)
diff --git a/tools/perf/util/evlist.h b/tools/perf/util/evlist.h
index 0843746bc389..bf2c4936e35f 100644
--- a/tools/perf/util/evlist.h
+++ b/tools/perf/util/evlist.h
@@ -265,6 +265,11 @@ bool perf_evlist__valid_read_format(struct perf_evlist *evlist);
void perf_evlist__splice_list_tail(struct perf_evlist *evlist,
struct list_head *list);
+static inline bool perf_evlist__empty(struct perf_evlist *evlist)
+{
+ return list_empty(&evlist->entries);
+}
+
static inline struct perf_evsel *perf_evlist__first(struct perf_evlist *evlist)
{
return list_entry(evlist->entries.next, struct perf_evsel, node);
diff --git a/tools/perf/util/sort.c b/tools/perf/util/sort.c
index 8b327c955a4f..12359bd986db 100644
--- a/tools/perf/util/sort.c
+++ b/tools/perf/util/sort.c
@@ -2563,7 +2563,7 @@ static const char *get_default_sort_order(struct perf_evlist *evlist)
BUG_ON(sort__mode >= ARRAY_SIZE(default_sort_orders));
- if (evlist == NULL)
+ if (evlist == NULL || perf_evlist__empty(evlist))
goto out_no_evlist;
evlist__for_each_entry(evlist, evsel) {
--
2.14.0.rc0.284.gd933b75aa4-goog
^ permalink raw reply related [flat|nested] 7+ messages in thread
* Re: [PATCH] perf tool sort: Use default sort if evlist is empty
2017-07-21 5:11 [PATCH] perf tool sort: Use default sort if evlist is empty David Carrillo-Cisneros
@ 2017-07-21 7:44 ` Jiri Olsa
2017-07-21 20:02 ` David Carrillo-Cisneros
2017-07-26 20:03 ` Arnaldo Carvalho de Melo
1 sibling, 1 reply; 7+ messages in thread
From: Jiri Olsa @ 2017-07-21 7:44 UTC (permalink / raw)
To: David Carrillo-Cisneros
Cc: linux-kernel, Ingo Molnar, Arnaldo Carvalho de Melo,
Alexander Shishkin, Andi Kleen, Simon Que, Wang Nan, Jiri Olsa,
Namhyung Kim, Stephane Eranian, Paul Turner
On Thu, Jul 20, 2017 at 10:11:57PM -0700, David Carrillo-Cisneros wrote:
> Fixes bug noted by Jiri in https://lkml.org/lkml/2017/6/13/755 and caused
> by commit d49dadea7862 ("perf tools: Make 'trace' or 'trace_fields' sort
> key default for tracepoint events")
> not taking into account that evlist is empty in pipe-mode.
>
> Before this commit, pipe mode will only show bogus "100.00% N/A" instead
> of correct output as follows:
>
> $ perf record -o - sleep 1 | perf report -i -
> # To display the perf.data header info, please use --header/--header-only options.
> #
> [ perf record: Woken up 1 times to write data ]
> [ perf record: Captured and wrote 0.000 MB - ]
> #
> # Total Lost Samples: 0
> #
> # Samples: 8 of event 'cycles:ppH'
> # Event count (approx.): 145658
> #
> # Overhead Trace output
> # ........ ............
> #
> 100.00% N/A
>
> Correct output, after patch:
>
> $ perf record -o - sleep 1 | perf report -i -
> # To display the perf.data header info, please use --header/--header-only options.
> #
> [ perf record: Woken up 1 times to write data ]
> [ perf record: Captured and wrote 0.000 MB - ]
> #
> # Total Lost Samples: 0
> #
> # Samples: 8 of event 'cycles:ppH'
> # Event count (approx.): 191331
> #
> # Overhead Command Shared Object Symbol
> # ........ ....... ................. .................................
> #
> 81.63% sleep libc-2.19.so [.] _exit
> 13.58% sleep ld-2.19.so [.] do_lookup_x
> 2.34% sleep [kernel.kallsyms] [k] context_switch
> 2.34% sleep libc-2.19.so [.] __GI___libc_nanosleep
> 0.11% perf [kernel.kallsyms] [k] __intel_pmu_enable_a
>
I wonder we could reinit the sortorder once we know what
events we have in pipe, and recognize the tracepoint output
properly:
[root@krava perf]# ./perf record -e 'sched:sched_switch' sleep 1 | ./perf report
# To display the perf.data header info, please use --header/--header-only options.
SNIP
#
# Overhead Command Shared Object Symbol
# ........ ....... ................. ..............
#
100.00% sleep [kernel.kallsyms] [k] __schedule
also I've got another crash for (added -a option for above example):
[root@krava perf]# ./perf record -e 'sched:sched_switch' -a sleep 1 | ./perf report
# To display the perf.data header info, please use --header/--header-only options.
#
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.000 MB (null) ]
Segmentation fault (core dumped)
catchsegv got:
/home/jolsa/kernel/linux-perf/tools/perf/util/ordered-events.c:85(free_dup_event)[0x51a6a5]
./perf(ordered_events__free+0x5c)[0x51b0b7]
/home/jolsa/kernel/linux-perf/tools/perf/util/session.c:1751(__perf_session__process_pipe_events)[0x518abb]
./perf(perf_session__process_events+0x91)[0x5190f0]
/home/jolsa/kernel/linux-perf/tools/perf/builtin-report.c:598(__cmd_report)[0x443a91]
./perf(cmd_report+0x169b)[0x4455a3]
/home/jolsa/kernel/linux-perf/tools/perf/perf.c:296(run_builtin)[0x4be1b0]
/home/jolsa/kernel/linux-perf/tools/perf/perf.c:348(handle_internal_command)[0x4be41d]
/home/jolsa/kernel/linux-perf/tools/perf/perf.c:395(run_argv)[0x4be56f]
./perf(main+0x2d6)[0x4be949]
/lib64/libc.so.6(__libc_start_main+0xf1)[0x7f3de8a10401]
./perf(_start+0x2a)[0x42831a]
looks like some mem corruption.. will try to follow up
on this later if nobody beats me to it ;-)
thanks,
jirka
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH] perf tool sort: Use default sort if evlist is empty
2017-07-21 7:44 ` Jiri Olsa
@ 2017-07-21 20:02 ` David Carrillo-Cisneros
2017-07-22 23:09 ` Namhyung Kim
0 siblings, 1 reply; 7+ messages in thread
From: David Carrillo-Cisneros @ 2017-07-21 20:02 UTC (permalink / raw)
To: Jiri Olsa
Cc: linux-kernel, Ingo Molnar, Arnaldo Carvalho de Melo,
Alexander Shishkin, Andi Kleen, Simon Que, Wang Nan, Jiri Olsa,
Namhyung Kim, Stephane Eranian, Paul Turner
On Fri, Jul 21, 2017 at 12:44 AM, Jiri Olsa <jolsa@redhat.com> wrote:
> On Thu, Jul 20, 2017 at 10:11:57PM -0700, David Carrillo-Cisneros wrote:
>> Fixes bug noted by Jiri in https://lkml.org/lkml/2017/6/13/755 and caused
>> by commit d49dadea7862 ("perf tools: Make 'trace' or 'trace_fields' sort
>> key default for tracepoint events")
>> not taking into account that evlist is empty in pipe-mode.
>>
>> Before this commit, pipe mode will only show bogus "100.00% N/A" instead
>> of correct output as follows:
>>
>> $ perf record -o - sleep 1 | perf report -i -
>> # To display the perf.data header info, please use --header/--header-only options.
>> #
>> [ perf record: Woken up 1 times to write data ]
>> [ perf record: Captured and wrote 0.000 MB - ]
>> #
>> # Total Lost Samples: 0
>> #
>> # Samples: 8 of event 'cycles:ppH'
>> # Event count (approx.): 145658
>> #
>> # Overhead Trace output
>> # ........ ............
>> #
>> 100.00% N/A
>>
>> Correct output, after patch:
>>
>> $ perf record -o - sleep 1 | perf report -i -
>> # To display the perf.data header info, please use --header/--header-only options.
>> #
>> [ perf record: Woken up 1 times to write data ]
>> [ perf record: Captured and wrote 0.000 MB - ]
>> #
>> # Total Lost Samples: 0
>> #
>> # Samples: 8 of event 'cycles:ppH'
>> # Event count (approx.): 191331
>> #
>> # Overhead Command Shared Object Symbol
>> # ........ ....... ................. .................................
>> #
>> 81.63% sleep libc-2.19.so [.] _exit
>> 13.58% sleep ld-2.19.so [.] do_lookup_x
>> 2.34% sleep [kernel.kallsyms] [k] context_switch
>> 2.34% sleep libc-2.19.so [.] __GI___libc_nanosleep
>> 0.11% perf [kernel.kallsyms] [k] __intel_pmu_enable_a
>>
>
> I wonder we could reinit the sortorder once we know what
> events we have in pipe, and recognize the tracepoint output
> properly:
I see this hard to do since, at any given point while traversing the
pipe's content, the best we can do is guess that we've seen all event
types. Then we'd need to fall back and redo the output whenever a new
sample refutes our last guess.
>
> [root@krava perf]# ./perf record -e 'sched:sched_switch' sleep 1 | ./perf report
> # To display the perf.data header info, please use --header/--header-only options.
>
> SNIP
>
> #
> # Overhead Command Shared Object Symbol
> # ........ ....... ................. ..............
> #
> 100.00% sleep [kernel.kallsyms] [k] __schedule
>
>
> also I've got another crash for (added -a option for above example):
>
> [root@krava perf]# ./perf record -e 'sched:sched_switch' -a sleep 1 | ./perf report
> # To display the perf.data header info, please use --header/--header-only options.
> #
> [ perf record: Woken up 1 times to write data ]
> [ perf record: Captured and wrote 0.000 MB (null) ]
> Segmentation fault (core dumped)
>
> catchsegv got:
> /home/jolsa/kernel/linux-perf/tools/perf/util/ordered-events.c:85(free_dup_event)[0x51a6a5]
> ./perf(ordered_events__free+0x5c)[0x51b0b7]
> /home/jolsa/kernel/linux-perf/tools/perf/util/session.c:1751(__perf_session__process_pipe_events)[0x518abb]
> ./perf(perf_session__process_events+0x91)[0x5190f0]
> /home/jolsa/kernel/linux-perf/tools/perf/builtin-report.c:598(__cmd_report)[0x443a91]
> ./perf(cmd_report+0x169b)[0x4455a3]
> /home/jolsa/kernel/linux-perf/tools/perf/perf.c:296(run_builtin)[0x4be1b0]
> /home/jolsa/kernel/linux-perf/tools/perf/perf.c:348(handle_internal_command)[0x4be41d]
> /home/jolsa/kernel/linux-perf/tools/perf/perf.c:395(run_argv)[0x4be56f]
> ./perf(main+0x2d6)[0x4be949]
> /lib64/libc.so.6(__libc_start_main+0xf1)[0x7f3de8a10401]
> ./perf(_start+0x2a)[0x42831a]
>
> looks like some mem corruption.. will try to follow up
> on this later if nobody beats me to it ;-)
Cannot reproduce it in acme's perf/core building the tool with
make NO_LIBPYTHON=1 LDFLAGS=-static
If you have a file with the perf record output causing perf report's
crash, I'd like to take a look.
Thanks,
David
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH] perf tool sort: Use default sort if evlist is empty
2017-07-21 20:02 ` David Carrillo-Cisneros
@ 2017-07-22 23:09 ` Namhyung Kim
2017-07-24 7:47 ` Jiri Olsa
2017-07-24 10:43 ` David Carrillo-Cisneros
0 siblings, 2 replies; 7+ messages in thread
From: Namhyung Kim @ 2017-07-22 23:09 UTC (permalink / raw)
To: David Carrillo-Cisneros
Cc: Jiri Olsa, linux-kernel, Ingo Molnar, Arnaldo Carvalho de Melo,
Alexander Shishkin, Andi Kleen, Simon Que, Wang Nan, Jiri Olsa,
Stephane Eranian, Paul Turner, kernel-team
On Fri, Jul 21, 2017 at 01:02:50PM -0700, David Carrillo-Cisneros wrote:
> On Fri, Jul 21, 2017 at 12:44 AM, Jiri Olsa <jolsa@redhat.com> wrote:
> > On Thu, Jul 20, 2017 at 10:11:57PM -0700, David Carrillo-Cisneros wrote:
> >> Fixes bug noted by Jiri in https://lkml.org/lkml/2017/6/13/755 and caused
> >> by commit d49dadea7862 ("perf tools: Make 'trace' or 'trace_fields' sort
> >> key default for tracepoint events")
> >> not taking into account that evlist is empty in pipe-mode.
> >>
> >> Before this commit, pipe mode will only show bogus "100.00% N/A" instead
> >> of correct output as follows:
> >>
> >> $ perf record -o - sleep 1 | perf report -i -
> >> # To display the perf.data header info, please use --header/--header-only options.
> >> #
> >> [ perf record: Woken up 1 times to write data ]
> >> [ perf record: Captured and wrote 0.000 MB - ]
> >> #
> >> # Total Lost Samples: 0
> >> #
> >> # Samples: 8 of event 'cycles:ppH'
> >> # Event count (approx.): 145658
> >> #
> >> # Overhead Trace output
> >> # ........ ............
> >> #
> >> 100.00% N/A
> >>
> >> Correct output, after patch:
> >>
> >> $ perf record -o - sleep 1 | perf report -i -
> >> # To display the perf.data header info, please use --header/--header-only options.
> >> #
> >> [ perf record: Woken up 1 times to write data ]
> >> [ perf record: Captured and wrote 0.000 MB - ]
> >> #
> >> # Total Lost Samples: 0
> >> #
> >> # Samples: 8 of event 'cycles:ppH'
> >> # Event count (approx.): 191331
> >> #
> >> # Overhead Command Shared Object Symbol
> >> # ........ ....... ................. .................................
> >> #
> >> 81.63% sleep libc-2.19.so [.] _exit
> >> 13.58% sleep ld-2.19.so [.] do_lookup_x
> >> 2.34% sleep [kernel.kallsyms] [k] context_switch
> >> 2.34% sleep libc-2.19.so [.] __GI___libc_nanosleep
> >> 0.11% perf [kernel.kallsyms] [k] __intel_pmu_enable_a
> >>
> >
> > I wonder we could reinit the sortorder once we know what
> > events we have in pipe, and recognize the tracepoint output
> > properly:
>
> I see this hard to do since, at any given point while traversing the
> pipe's content, the best we can do is guess that we've seen all event
> types. Then we'd need to fall back and redo the output whenever a new
> sample refutes our last guess.
After reading feature event, you could know the number of events, no?
Thanks,
Namhyung
>
> >
> > [root@krava perf]# ./perf record -e 'sched:sched_switch' sleep 1 | ./perf report
> > # To display the perf.data header info, please use --header/--header-only options.
> >
> > SNIP
> >
> > #
> > # Overhead Command Shared Object Symbol
> > # ........ ....... ................. ..............
> > #
> > 100.00% sleep [kernel.kallsyms] [k] __schedule
> >
> >
> > also I've got another crash for (added -a option for above example):
> >
> > [root@krava perf]# ./perf record -e 'sched:sched_switch' -a sleep 1 | ./perf report
> > # To display the perf.data header info, please use --header/--header-only options.
> > #
> > [ perf record: Woken up 1 times to write data ]
> > [ perf record: Captured and wrote 0.000 MB (null) ]
> > Segmentation fault (core dumped)
> >
> > catchsegv got:
> > /home/jolsa/kernel/linux-perf/tools/perf/util/ordered-events.c:85(free_dup_event)[0x51a6a5]
> > ./perf(ordered_events__free+0x5c)[0x51b0b7]
> > /home/jolsa/kernel/linux-perf/tools/perf/util/session.c:1751(__perf_session__process_pipe_events)[0x518abb]
> > ./perf(perf_session__process_events+0x91)[0x5190f0]
> > /home/jolsa/kernel/linux-perf/tools/perf/builtin-report.c:598(__cmd_report)[0x443a91]
> > ./perf(cmd_report+0x169b)[0x4455a3]
> > /home/jolsa/kernel/linux-perf/tools/perf/perf.c:296(run_builtin)[0x4be1b0]
> > /home/jolsa/kernel/linux-perf/tools/perf/perf.c:348(handle_internal_command)[0x4be41d]
> > /home/jolsa/kernel/linux-perf/tools/perf/perf.c:395(run_argv)[0x4be56f]
> > ./perf(main+0x2d6)[0x4be949]
> > /lib64/libc.so.6(__libc_start_main+0xf1)[0x7f3de8a10401]
> > ./perf(_start+0x2a)[0x42831a]
> >
> > looks like some mem corruption.. will try to follow up
> > on this later if nobody beats me to it ;-)
>
> Cannot reproduce it in acme's perf/core building the tool with
> make NO_LIBPYTHON=1 LDFLAGS=-static
>
> If you have a file with the perf record output causing perf report's
> crash, I'd like to take a look.
>
> Thanks,
> David
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH] perf tool sort: Use default sort if evlist is empty
2017-07-22 23:09 ` Namhyung Kim
@ 2017-07-24 7:47 ` Jiri Olsa
2017-07-24 10:43 ` David Carrillo-Cisneros
1 sibling, 0 replies; 7+ messages in thread
From: Jiri Olsa @ 2017-07-24 7:47 UTC (permalink / raw)
To: Namhyung Kim
Cc: David Carrillo-Cisneros, linux-kernel, Ingo Molnar,
Arnaldo Carvalho de Melo, Alexander Shishkin, Andi Kleen,
Simon Que, Wang Nan, Jiri Olsa, Stephane Eranian, Paul Turner,
kernel-team
On Sun, Jul 23, 2017 at 08:09:49AM +0900, Namhyung Kim wrote:
SNIP
> > > also I've got another crash for (added -a option for above example):
> > >
> > > [root@krava perf]# ./perf record -e 'sched:sched_switch' -a sleep 1 | ./perf report
> > > # To display the perf.data header info, please use --header/--header-only options.
> > > #
> > > [ perf record: Woken up 1 times to write data ]
> > > [ perf record: Captured and wrote 0.000 MB (null) ]
> > > Segmentation fault (core dumped)
> > >
> > > catchsegv got:
> > > /home/jolsa/kernel/linux-perf/tools/perf/util/ordered-events.c:85(free_dup_event)[0x51a6a5]
> > > ./perf(ordered_events__free+0x5c)[0x51b0b7]
> > > /home/jolsa/kernel/linux-perf/tools/perf/util/session.c:1751(__perf_session__process_pipe_events)[0x518abb]
> > > ./perf(perf_session__process_events+0x91)[0x5190f0]
> > > /home/jolsa/kernel/linux-perf/tools/perf/builtin-report.c:598(__cmd_report)[0x443a91]
> > > ./perf(cmd_report+0x169b)[0x4455a3]
> > > /home/jolsa/kernel/linux-perf/tools/perf/perf.c:296(run_builtin)[0x4be1b0]
> > > /home/jolsa/kernel/linux-perf/tools/perf/perf.c:348(handle_internal_command)[0x4be41d]
> > > /home/jolsa/kernel/linux-perf/tools/perf/perf.c:395(run_argv)[0x4be56f]
> > > ./perf(main+0x2d6)[0x4be949]
> > > /lib64/libc.so.6(__libc_start_main+0xf1)[0x7f3de8a10401]
> > > ./perf(_start+0x2a)[0x42831a]
> > >
> > > looks like some mem corruption.. will try to follow up
> > > on this later if nobody beats me to it ;-)
> >
> > Cannot reproduce it in acme's perf/core building the tool with
> > make NO_LIBPYTHON=1 LDFLAGS=-static
> >
> > If you have a file with the perf record output causing perf report's
> > crash, I'd like to take a look.
hm, I can't reproduce any longer.. :-\
jirka
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH] perf tool sort: Use default sort if evlist is empty
2017-07-22 23:09 ` Namhyung Kim
2017-07-24 7:47 ` Jiri Olsa
@ 2017-07-24 10:43 ` David Carrillo-Cisneros
1 sibling, 0 replies; 7+ messages in thread
From: David Carrillo-Cisneros @ 2017-07-24 10:43 UTC (permalink / raw)
To: Namhyung Kim
Cc: Jiri Olsa, linux-kernel, Ingo Molnar, Arnaldo Carvalho de Melo,
Alexander Shishkin, Andi Kleen, Simon Que, Wang Nan, Jiri Olsa,
Stephane Eranian, Paul Turner, kernel-team
On Sat, Jul 22, 2017 at 4:09 PM, Namhyung Kim <namhyung@kernel.org> wrote:
> On Fri, Jul 21, 2017 at 01:02:50PM -0700, David Carrillo-Cisneros wrote:
>> On Fri, Jul 21, 2017 at 12:44 AM, Jiri Olsa <jolsa@redhat.com> wrote:
>> > On Thu, Jul 20, 2017 at 10:11:57PM -0700, David Carrillo-Cisneros wrote:
>> >> Fixes bug noted by Jiri in https://lkml.org/lkml/2017/6/13/755 and caused
>> >> by commit d49dadea7862 ("perf tools: Make 'trace' or 'trace_fields' sort
>> >> key default for tracepoint events")
>> >> not taking into account that evlist is empty in pipe-mode.
>> >>
>> >> Before this commit, pipe mode will only show bogus "100.00% N/A" instead
>> >> of correct output as follows:
>> >>
>> >> $ perf record -o - sleep 1 | perf report -i -
>> >> # To display the perf.data header info, please use --header/--header-only options.
>> >> #
>> >> [ perf record: Woken up 1 times to write data ]
>> >> [ perf record: Captured and wrote 0.000 MB - ]
>> >> #
>> >> # Total Lost Samples: 0
>> >> #
>> >> # Samples: 8 of event 'cycles:ppH'
>> >> # Event count (approx.): 145658
>> >> #
>> >> # Overhead Trace output
>> >> # ........ ............
>> >> #
>> >> 100.00% N/A
>> >>
>> >> Correct output, after patch:
>> >>
>> >> $ perf record -o - sleep 1 | perf report -i -
>> >> # To display the perf.data header info, please use --header/--header-only options.
>> >> #
>> >> [ perf record: Woken up 1 times to write data ]
>> >> [ perf record: Captured and wrote 0.000 MB - ]
>> >> #
>> >> # Total Lost Samples: 0
>> >> #
>> >> # Samples: 8 of event 'cycles:ppH'
>> >> # Event count (approx.): 191331
>> >> #
>> >> # Overhead Command Shared Object Symbol
>> >> # ........ ....... ................. .................................
>> >> #
>> >> 81.63% sleep libc-2.19.so [.] _exit
>> >> 13.58% sleep ld-2.19.so [.] do_lookup_x
>> >> 2.34% sleep [kernel.kallsyms] [k] context_switch
>> >> 2.34% sleep libc-2.19.so [.] __GI___libc_nanosleep
>> >> 0.11% perf [kernel.kallsyms] [k] __intel_pmu_enable_a
>> >>
>> >
>> > I wonder we could reinit the sortorder once we know what
>> > events we have in pipe, and recognize the tracepoint output
>> > properly:
>>
>> I see this hard to do since, at any given point while traversing the
>> pipe's content, the best we can do is guess that we've seen all event
>> types. Then we'd need to fall back and redo the output whenever a new
>> sample refutes our last guess.
>
> After reading feature event, you could know the number of events, no?
True. Also the tool could extract the events from HEADER_EVENT_DESC
feature event and adjust output accordingly. That'd be a nice to have
feature.
Thanks,
David
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH] perf tool sort: Use default sort if evlist is empty
2017-07-21 5:11 [PATCH] perf tool sort: Use default sort if evlist is empty David Carrillo-Cisneros
2017-07-21 7:44 ` Jiri Olsa
@ 2017-07-26 20:03 ` Arnaldo Carvalho de Melo
1 sibling, 0 replies; 7+ messages in thread
From: Arnaldo Carvalho de Melo @ 2017-07-26 20:03 UTC (permalink / raw)
To: David Carrillo-Cisneros
Cc: linux-kernel, Ingo Molnar, Alexander Shishkin, Andi Kleen,
Simon Que, Wang Nan, Jiri Olsa, Namhyung Kim, Stephane Eranian,
Paul Turner
Em Thu, Jul 20, 2017 at 10:11:57PM -0700, David Carrillo-Cisneros escreveu:
> Fixes bug noted by Jiri in https://lkml.org/lkml/2017/6/13/755 and caused
> by commit d49dadea7862 ("perf tools: Make 'trace' or 'trace_fields' sort
> key default for tracepoint events")
> not taking into account that evlist is empty in pipe-mode.
>
> Before this commit, pipe mode will only show bogus "100.00% N/A" instead
> of correct output as follows:
>
Thanks, tested and applied.
- Arnaldo
^ permalink raw reply [flat|nested] 7+ messages in thread
end of thread, other threads:[~2017-07-26 20:03 UTC | newest]
Thread overview: 7+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2017-07-21 5:11 [PATCH] perf tool sort: Use default sort if evlist is empty David Carrillo-Cisneros
2017-07-21 7:44 ` Jiri Olsa
2017-07-21 20:02 ` David Carrillo-Cisneros
2017-07-22 23:09 ` Namhyung Kim
2017-07-24 7:47 ` Jiri Olsa
2017-07-24 10:43 ` David Carrillo-Cisneros
2017-07-26 20:03 ` Arnaldo Carvalho de Melo
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