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perf callchain: Use global caching provided by libunwind

The libunwind provides two caching policy which are global and
per-thread.  As perf unwinds callchains in a single thread, it'd
sufficient to use global caching.

This speeds up my perf report from 14s to 7s on a ~260MB data file.
Although the output sometimes contains a slight difference (~0.01% in
terms of number of lines printed) on callchains which were not resolved.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jean Pihet <jean.pihet@linaro.org>
Cc: Arun Sharma <asharma@fb.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jean Pihet <jean.pihet@linaro.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1412556363-26229-4-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
wifi-calibration
Namhyung Kim 2014-10-06 09:46:01 +09:00 committed by Arnaldo Carvalho de Melo
parent 1776b10627
commit 380b5143ab
3 changed files with 18 additions and 0 deletions

View File

@ -117,6 +117,9 @@ int __thread__set_comm(struct thread *thread, const char *str, u64 timestamp,
if (!new)
return -ENOMEM;
list_add(&new->list, &thread->comm_list);
if (exec)
unwind__flush_access(thread);
}
thread->comm_set = true;

View File

@ -539,11 +539,23 @@ int unwind__prepare_access(struct thread *thread)
return -ENOMEM;
}
unw_set_caching_policy(addr_space, UNW_CACHE_GLOBAL);
thread__set_priv(thread, addr_space);
return 0;
}
void unwind__flush_access(struct thread *thread)
{
unw_addr_space_t addr_space;
if (callchain_param.record_mode != CALLCHAIN_DWARF)
return;
addr_space = thread__priv(thread);
unw_flush_cache(addr_space, 0, 0);
}
void unwind__finish_access(struct thread *thread)
{
unw_addr_space_t addr_space;

View File

@ -23,6 +23,7 @@ int unwind__get_entries(unwind_entry_cb_t cb, void *arg,
#ifdef HAVE_LIBUNWIND_SUPPORT
int libunwind__arch_reg_id(int regnum);
int unwind__prepare_access(struct thread *thread);
void unwind__flush_access(struct thread *thread);
void unwind__finish_access(struct thread *thread);
#else
static inline int unwind__prepare_access(struct thread *thread __maybe_unused)
@ -30,6 +31,7 @@ static inline int unwind__prepare_access(struct thread *thread __maybe_unused)
return 0;
}
static inline void unwind__flush_access(struct thread *thread __maybe_unused) {}
static inline void unwind__finish_access(struct thread *thread __maybe_unused) {}
#endif
#else
@ -49,6 +51,7 @@ static inline int unwind__prepare_access(struct thread *thread __maybe_unused)
return 0;
}
static inline void unwind__flush_access(struct thread *thread __maybe_unused) {}
static inline void unwind__finish_access(struct thread *thread __maybe_unused) {}
#endif /* HAVE_DWARF_UNWIND_SUPPORT */
#endif /* __UNWIND_H */