Subject: Re: [PATCH/RFC v3] perf core: Allow setting up max frame stack depth
 via sysctl
To: Arnaldo Carvalho de Melo <arnaldo.melo@gmail.com>,
        Brendan Gregg <brendan.d.gregg@gmail.com>
References: <20160425192229.GC25218@kernel.org>
 <20160425200646.GA23875@ast-mbp.thefacebook.com>
 <20160425201750.GD25218@kernel.org>
 <20160425215947.GA25915@ast-mbp.thefacebook.com>
 <20160425234138.GA16708@kernel.org>
 <20160426000724.GA28705@ast-mbp.thefacebook.com>
 <20160426002928.GB16708@kernel.org>
 <20160426004358.GA29875@ast-mbp.thefacebook.com>
 <20160426004747.GC16708@kernel.org>
 <CAE40pdeG-TrtBNS10XDQx2ynFqRAhbgENrU7g-_3Oqho047E0A@mail.gmail.com>
 <20160426163321.GI11033@kernel.org>
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Frederic Weisbecker <fweisbec@gmail.com>,
        Ingo Molnar <mingo@kernel.org>,
        Adrian Hunter <adrian.hunter@intel.com>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Alexei Starovoitov <ast@kernel.org>, He Kuang <hekuang@huawei.com>,
        Jiri Olsa <jolsa@redhat.com>, Masami Hiramatsu <mhiramat@kernel.org>,
        Milian Wolff <milian.wolff@kdab.com>,
        Namhyung Kim <namhyung@kernel.org>,
        Stephane Eranian <eranian@google.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Vince Weaver <vincent.weaver@maine.edu>,
        Wang Nan <wangnan0@huawei.com>, Zefan Li <lizefan@huawei.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
From: David Ahern <dsahern@gmail.com>
Message-ID: <571F9B28.8040001@gmail.com>
Date: Tue, 26 Apr 2016 10:45:28 -0600
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On 4/26/16 10:33 AM, Arnaldo Carvalho de Melo wrote:
> So, for completeness, further testing it to see how far it goes on a 8GB
> machine I got:
>
> [root@emilia ~]# echo 131100 > /proc/sys/kernel/perf_event_max_stack
> [root@emilia ~]# perf record -g ls
> Error:
> The sys_perf_event_open() syscall returned with 12 (Cannot allocate memory) for event (cycles).
> /bin/dmesg may provide additional information.
> No CONFIG_PERF_EVENTS=y kernel support configured?

I thought we fixed up the last line to not display for errors like this.

How about adding ENOMEM case to perf_evsel__open_strerror?