From bfaef4b46b17ff053dc38f979cec364b0715cabb Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Thu, 8 Nov 2012 18:08:26 -0300 Subject: [PATCH] perf diff: Use hists__link when not pairing just with baseline Previously there were blind spots because we were not looking at symbols that didn't ocurred in the latest run: # perf record usleep 1 [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.018 MB perf.data (~801 samples) ] # perf record usleep 1 [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.018 MB perf.data (~801 samples) ] Before: # perf diff # Event 'cycles' # # Baseline Delta Shared Object Symbol # ........ ....... ................. ............................. # +10.38% [kernel.kallsyms] [k] get_empty_filp +9.51% [kernel.kallsyms] [k] update_sd_lb_stats +9.41% libpopt.so.0.0.0 [.] _init +9.29% [kernel.kallsyms] [k] vma_interval_tree_insert 9.05% +0.12% [kernel.kallsyms] [k] do_sys_open +9.14% [kernel.kallsyms] [k] kfree +8.98% [kernel.kallsyms] [k] free_pages_and_swap_cache +8.78% [kernel.kallsyms] [k] unmap_page_range 9.36% -0.90% [kernel.kallsyms] [k] zap_pte_range 7.60% +0.09% [kernel.kallsyms] [k] find_next_bit +4.37% [kernel.kallsyms] [k] place_entity +3.38% [kernel.kallsyms] [k] __do_page_fault +0.80% [kernel.kallsyms] [k] native_apic_mem_write 0.21% +0.43% [kernel.kallsyms] [k] native_write_msr_safe # So 9.05 + 9.36 + 7.60 + 0.21 != 100% Now using the recently introduced hists__link we can see the whole picture: # perf diff # Event 'cycles' # # Baseline Delta Shared Object Symbol # ........ ....... ................. ............................. # 8.44% -8.44% [kernel.kallsyms] [k] _raw_spin_lock 9.05% -9.05% [kernel.kallsyms] [k] sha_transform 10.55% -10.55% [kernel.kallsyms] [k] __d_lookup_rcu +10.38% [kernel.kallsyms] [k] get_empty_filp 17.70% -17.70% [kernel.kallsyms] [k] kmem_cache_free +9.51% [kernel.kallsyms] [k] update_sd_lb_stats +9.41% libpopt.so.0.0.0 [.] _init +9.29% [kernel.kallsyms] [k] vma_interval_tree_insert 9.05% +0.12% [kernel.kallsyms] [k] do_sys_open +9.14% [kernel.kallsyms] [k] kfree +8.98% [kernel.kallsyms] [k] free_pages_and_swap_cache +8.78% [kernel.kallsyms] [k] unmap_page_range 9.36% -0.90% [kernel.kallsyms] [k] zap_pte_range 7.60% +0.09% [kernel.kallsyms] [k] find_next_bit +4.37% [kernel.kallsyms] [k] place_entity +3.38% [kernel.kallsyms] [k] __do_page_fault 4.01% -4.01% [kernel.kallsyms] [k] handle_pte_fault 9.27% -9.27% [kernel.kallsyms] [k] find_get_page 0.78% -0.78% [kernel.kallsyms] [k] rcu_irq_enter 0.57% -0.57% [kernel.kallsyms] [k] finish_task_switch 4.25% -4.25% [kernel.kallsyms] [k] run_timer_softirq +0.80% [kernel.kallsyms] [k] native_apic_mem_write 0.21% +0.43% [kernel.kallsyms] [k] native_write_msr_safe 9.16% -9.16% ld-2.12.so [.] close # Now: 8.44 + 9.05 + 10.55 + 17.70 + 9.05 + 9.36 + 7.60 + 4.01 + 9.27 + 0.78 + 0.57 + 4.25 + 0.21 + 9.16 == 100% Cc: David Ahern Cc: Frederic Weisbecker Cc: Jiri Olsa Cc: Mike Galbraith Cc: Namhyung Kim Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Stephane Eranian Link: http://lkml.kernel.org/n/tip-jeq55qdgby1745bs8r9sscdh@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-diff.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/tools/perf/builtin-diff.c b/tools/perf/builtin-diff.c index e99fb3bc1c2..93b852f8a5d 100644 --- a/tools/perf/builtin-diff.c +++ b/tools/perf/builtin-diff.c @@ -491,6 +491,8 @@ static void hists__process(struct hists *old, struct hists *new) if (show_baseline_only) hists__baseline_only(new); + else + hists__link(new, old); if (sort_compute) { hists__precompute(new);