From: John Garry <john.garry@huawei.com>
To: Jiri Olsa <jolsa@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>, Ingo Molnar <mingo@redhat.com>,
"Peter Zijlstra" <peterz@infradead.org>,
Arnaldo Carvalho de Melo <acme@kernel.org>,
Alexander Shishkin <alexander.shishkin@linux.intel.com>,
Linuxarm <linuxarm@huawei.com>,
"linux-arm-kernel@lists.infradead.org"
<linux-arm-kernel@lists.infradead.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
Namhyung Kim <namhyung@kernel.org>,
"Will Deacon" <will.deacon@arm.com>,
Mark Rutland <mark.rutland@arm.com>
Subject: Re: [PATCH] perf tools: Allocate id array in perf_event__synthesize_event_update_cpus
Date: Wed, 3 Oct 2018 15:08:10 +0100 [thread overview]
Message-ID: <594506a2-8cb3-3d09-82ab-5cb6d8c31ed0@huawei.com> (raw)
In-Reply-To: <20181003113643.GA31725@krava>
On 03/10/2018 12:36, Jiri Olsa wrote:
> On Tue, Oct 02, 2018 at 01:16:21PM +0200, Jiri Olsa wrote:
>> On Tue, Oct 02, 2018 at 11:41:36AM +0100, John Garry wrote:
>>
>> SNIP
>>
>>>>
>>>>
>>>> ---
>>>> diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
>>>> index 1ec1d9bc2d63..fb2a0dab3978 100644
>>>> --- a/tools/perf/util/header.c
>>>> +++ b/tools/perf/util/header.c
>>>> @@ -29,6 +29,7 @@
>>>> #include "symbol.h"
>>>> #include "debug.h"
>>>> #include "cpumap.h"
>>>> +#include "thread_map.h"
>>>> #include "pmu.h"
>>>> #include "vdso.h"
>>>> #include "strbuf.h"
>>>> @@ -3579,6 +3580,11 @@ perf_event__synthesize_event_update_cpus(struct perf_tool *tool,
>>>> if (!evsel->own_cpus)
>>>> return 0;
>>>>
>>>> + if (!evsel->id ||
>>>
>>> for my test, evsel->id is NULL
>>>
>>>> + perf_evsel__alloc_id(evsel, cpu_map__nr(evsel->cpus),
>>>> + thread_map__nr(evsel->threads)))
>>>
>>> and then this function is not called as we return immediately. So did you
>>> really want this:
>>>
>>> if (!evsel->id && perf_evsel__alloc_id(...))
>>> return -ENOMEM;
>>
>> ugh.. yes ;-) thanks for the fix.. I'll double
>> check the logic and post the patch this week
>
> actualy, we also need to populate those ids ;-)
> so calling perf_evsel__store_ids instead..
> attaching the full patch
>
> thanks,
> jirka
>
Hi Jirka,
Can you please double-check your new patch, as I'm getting this now:
root@localhost:~# ./perf_debug record -e armv8_pmuv3_0/br_mis_pred/ sleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.001 MB perf.data (6 samples) ]
root@localhost:~# ./perf_debug report
0xe8 [0]: failed to process type: 461
Error:
failed to process sample
# To display the perf.data header info, please use
--header/--header-only option
#
root@localhost:~#
Thanks,
John
>
> ---
> John reported crash when recording on an event under
> pmu with cpumask defined:
>
> root@localhost:~# ./perf_debug_ record -e armv8_pmuv3_0/br_mis_pred/ sleep 1
> perf: Segmentation fault
> Obtained 9 stack frames.
> ./perf_debug_() [0x4c5ef8]
> [0xffff82ba267c]
> ./perf_debug_() [0x4bc5a8]
> ./perf_debug_() [0x419550]
> ./perf_debug_() [0x41a928]
> ./perf_debug_() [0x472f58]
> ./perf_debug_() [0x473210]
> ./perf_debug_() [0x4070f4]
> /lib/aarch64-linux-gnu/libc.so.6(__libc_start_main+0xe0) [0xffff8294c8a0]
> Segmentation fault (core dumped)
>
> We synthesize an update event that needs to touch the evsel
> id array, which is not defined at that time. Fixing this
> by allocating the array and getting IDs before it's used.
>
> Reported-by: John Garry <john.garry@huawei.com>
> Link: http://lkml.kernel.org/n/tip-8x4n7o34yheigoxm1jibflm6@git.kernel.org
> Signed-off-by: Jiri Olsa <jolsa@kernel.org>
> ---
> tools/perf/util/header.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
> index 1ec1d9bc2d63..14ca27f79d4a 100644
> --- a/tools/perf/util/header.c
> +++ b/tools/perf/util/header.c
> @@ -29,6 +29,7 @@
> #include "symbol.h"
> #include "debug.h"
> #include "cpumap.h"
> +#include "thread_map.h"
> #include "pmu.h"
> #include "vdso.h"
> #include "strbuf.h"
> @@ -3579,6 +3580,9 @@ perf_event__synthesize_event_update_cpus(struct perf_tool *tool,
> if (!evsel->own_cpus)
> return 0;
>
> + if (!evsel->id && perf_evsel__store_ids(evsel, evsel->evlist))
> + return -ENOMEM;
> +
> ev = cpu_map_data__alloc(evsel->own_cpus, &size, &type, &max);
> if (!ev)
> return -ENOMEM;
>
next prev parent reply other threads:[~2018-10-03 14:08 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-09-25 15:53 perf segmentation fault from NULL dereference John Garry
2018-09-27 3:00 ` Andi Kleen
2018-10-02 10:20 ` John Garry
2018-09-27 16:02 ` Jiri Olsa
2018-10-02 10:41 ` John Garry
2018-10-02 11:16 ` Jiri Olsa
2018-10-03 11:36 ` [PATCH] perf tools: Allocate id array in perf_event__synthesize_event_update_cpus Jiri Olsa
2018-10-03 14:08 ` John Garry [this message]
2018-10-03 14:16 ` Jiri Olsa
2018-10-03 21:20 ` [PATCH] perf tools: Store ids for events with their own cpus perf_event__synthesize_event_update_cpus Jiri Olsa
2018-10-04 9:20 ` John Garry
2018-10-09 10:00 ` Jiri Olsa
2018-10-12 13:25 ` John Garry
2018-10-15 19:15 ` Arnaldo Carvalho de Melo
2018-10-16 9:10 ` John Garry
2018-10-16 10:47 ` Jiri Olsa
2018-10-18 6:18 ` [tip:perf/urgent] perf evsel: " tip-bot for Jiri Olsa
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=594506a2-8cb3-3d09-82ab-5cb6d8c31ed0@huawei.com \
--to=john.garry@huawei.com \
--cc=acme@kernel.org \
--cc=ak@linux.intel.com \
--cc=alexander.shishkin@linux.intel.com \
--cc=jolsa@redhat.com \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linuxarm@huawei.com \
--cc=mark.rutland@arm.com \
--cc=mingo@redhat.com \
--cc=namhyung@kernel.org \
--cc=peterz@infradead.org \
--cc=will.deacon@arm.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).