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SubjectRe: [PATCH v6 0/7] perf diff: diff cycles at basic block level
Em Fri, Jun 28, 2019 at 10:02:55AM +0200, Jiri Olsa escreveu:
> On Fri, Jun 28, 2019 at 05:22:57PM +0800, Jin Yao wrote:
> > In some cases small changes in hot loops can show big differences.
> > But it's difficult to identify these differences.
> >
> > perf diff currently can only diff symbols (functions). We can also expand
> > it to diff cycles of individual programs blocks as reported by timed LBR.
> > This would allow to identify changes in specific code accurately.
> >
> > With this patch set, for example,
> >
> > $ perf record -b ./div
> > $ perf record -b ./div
> > $ perf diff -c cycles
> >
> > # Event 'cycles'
> > #
> > # Baseline [Program Block Range] Cycles Diff Shared Object Symbol
> > # ........ ...................................................................... ................ ..................................
> > #
> > 48.75% [div.c:42 -> div.c:45] 147 div [.] main
> > 48.75% [div.c:31 -> div.c:40] 4 div [.] main
> > 48.75% [div.c:40 -> div.c:40] 0 div [.] main
> > 48.75% [div.c:42 -> div.c:42] 0 div [.] main
> > 48.75% [div.c:42 -> div.c:44] 0 div [.] main
> > 19.02% [random_r.c:357 -> random_r.c:360] 0 libc-2.23.so [.] __random_r

> Reviewed-by: Jiri Olsa <jolsa@kernel.org>

Looks really nice, thanks, applied.

- Arnaldo

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