Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1237167

Re: [PATCH v7 0/4] perf: add support for profiling jitted code

Show all headers | View raw

On Thu, Oct 01, 2015 at 08:45:44AM +0200, Stephane Eranian wrote:
> This patch series extends perf record/report/annotate to enable
> profiling of jitted (just-in-time compiled) code. The current
> perf tool provides very limited support for profiling jitted
> code for some runtime environments. But the support is experimental
> and cannot be used in complex environments. It relies on files
> in /tmp, for instance. It does not support annotate mode or
> rejitted code.
> 
> This patch series adds a better way of profiling jitted code
> with the following advantages:
>    - support any jitted code environment (some with modifications)
>    - support Java runtime with JVMTI interface with no modifications
>    - provides a portable JVMTI agent library
>    - known to support V8 runtime
>    - known to support DART runtime
>    - supports code rejitting and code movements
>    - no files in /tmp
>    - meta-data file is unique to each run
>    - no changes to perf report/annotate
>    - support per-thread and system-wide profiling
>    - support monitoring of multiple simultaneous Jit runtimes
>    - source level view in perf annotate
> 
> The support is based on cooperation with the runtime. For Java runtimes,
> supporting the JVMTI interface, there is no change necessary. For other
> runtimes, modifications are necessary to emit the meta-data to support
> symbolization, annotation, source lines correlation of the samples.
> Those modifications are relatively straighforward, some have been 
> implemented in V8 and DART.

Do V8 and DART come with these bits or will that be a future
contribution?

> This will also generate an ELF image for each jitted function. The
> injected MMAP records will point to these ELF images. The reasoning
> behind using ELF images is that it makes processing for perf report
> and annotate automatic and transparent. It also makes it easier to
> package and analyze on a remote machine. Binutils tools can decode
> the ELF images easily.

The generation of ELF files is really nice!

All in all this looks really nice.

Thanks for doing this.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

[PATCH v7 0/4] perf: add support for profiling jitted code Stephane Eranian <eranian@google.com> - 2015-10-01 08:50 +0200
  [PATCH v7 5/5] perf/jit: add source line info support Stephane Eranian <eranian@google.com> - 2015-10-01 08:50 +0200
  [PATCH v7 4/5] perf tools: add JVMTI agent library Stephane Eranian <eranian@google.com> - 2015-10-01 08:50 +0200
  Re: [PATCH v7 0/4] perf: add support for profiling jitted code Peter Zijlstra <peterz@infradead.org> - 2015-10-01 11:20 +0200
    Re: [PATCH v7 0/4] perf: add support for profiling jitted code Ingo Molnar <mingo@kernel.org> - 2015-10-01 11:40 +0200
      Re: [PATCH v7 0/4] perf: add support for profiling jitted code Arnaldo Carvalho de Melo <acme@redhat.com> - 2015-10-01 18:20 +0200
    Re: [PATCH v7 0/4] perf: add support for profiling jitted code Stephane Eranian <eranian@google.com> - 2015-10-04 22:00 +0200
  Re: [PATCH v7 0/4] perf: add support for profiling jitted code Brendan Gregg <brendan.d.gregg@gmail.com> - 2015-10-02 00:50 +0200
    Re: [PATCH v7 0/4] perf: add support for profiling jitted code Stephane Eranian <eranian@google.com> - 2015-10-04 22:10 +0200

csiph-web