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 majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
