From: Namhyung Kim <[email protected]> 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 <[email protected]> Acked-by: Jean Pihet <[email protected]> Cc: Arun Sharma <[email protected]> Cc: David Ahern <[email protected]> Cc: Frederic Weisbecker <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Jean Pihet <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Paul Mackerras <[email protected]> Cc: Peter Zijlstra <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]> --- tools/perf/util/thread.c | 3 +++ tools/perf/util/unwind-libunwind.c | 12 ++++++++++++ tools/perf/util/unwind.h | 3 +++ 3 files changed, 18 insertions(+) diff --git a/tools/perf/util/thread.c b/tools/perf/util/thread.c index 2b7b2d91c016..c41411726c7a 100644 --- a/tools/perf/util/thread.c +++ b/tools/perf/util/thread.c @@ -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; diff --git a/tools/perf/util/unwind-libunwind.c b/tools/perf/util/unwind-libunwind.c index e060386165c5..4d45c0dfe343 100644 --- a/tools/perf/util/unwind-libunwind.c +++ b/tools/perf/util/unwind-libunwind.c @@ -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; diff --git a/tools/perf/util/unwind.h b/tools/perf/util/unwind.h index c17c4855bdbc..f50b737235eb 100644 --- a/tools/perf/util/unwind.h +++ b/tools/perf/util/unwind.h @@ -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 */ -- 1.9.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
