linux/tools/perf/builtin-diff.c, branch v3.8

perf diff: Use hists__link when not pairing just with baseline

2012-11-08T21:08:26Z

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

perf diff: Move hists__match to the hists lib

2012-11-08T20:57:37Z

Its not 'diff' specific and will be useful for other use cases, like bucketizing multiple events in a single session. 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-o35urjgxfxxm70aw1wa81s4w@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf diff: Start moving to support matching more than two hists

2012-11-08T20:43:09Z

We want to match more than two hists, so that we can match more than two perf.data files and moreover, match hist_entries (buckets) in multiple events in a group. So the "baseline"/"leader" will instead of a ->pair pointer, use a list_head, that will link to the pairs and hists__match use it. Following that perf_evlist__link will link the hists in its evsel groups. 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-2kbmzepoi544ygj9godseqpv@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf event: No need to create a thread when handling PERF_RECORD_EXIT

2012-10-06T19:33:45Z

When we were processing a PERF_RECORD_EXIT event we first used machine__findnew_thread for both the thread exiting and for its parent, only to use just the thread struct associated with the one exiting, and to just delete it. If it existed, i.e. not created at this very moment in machine__findnew_thread, it will be moved to the machine->dead_threads linked list, because we may have hist_entries pointing to it, but if it was created just do be deleted, it will just sit there with no references at all. Use the new machine__find_thread() method so that if it is not there, we don't create it. As a bonus the parent thread will also not be created at this point. Create process_fork() and process_exit() helpers to use this and make the builtins use it instead of the generic process_task(), ditched by this patch. 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-z7n2y98ebjyrvmytaope4vdl@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf diff: Include samples without symbol in overall stats

2012-10-05T17:14:49Z

Currently we omit samples without symbols. This way we get different and confusing numbers for samples than from report command. Signed-off-by: Jiri Olsa Cc: Andi Kleen Cc: Corey Ashford Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Namhyung Kim Cc: Paul Mackerras Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1349448287-18919-8-git-send-email-jolsa@redhat.com Signed-off-by: Arnaldo Carvalho de Melo

perf diff: Add -F option to display formula for computation

2012-10-05T17:13:36Z

Adding -F option to display the formula for specified computation. This is mainly to facilitate debugging, but can be useful anyway. Signed-off-by: Jiri Olsa Cc: Andi Kleen Cc: Corey Ashford Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Namhyung Kim Cc: Paul Mackerras Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1349448287-18919-7-git-send-email-jolsa@redhat.com Signed-off-by: Arnaldo Carvalho de Melo

perf diff: Add -p option to display period values for hist entries

2012-10-05T17:11:47Z

Adding -p option to show period values for both compared hist entries. Showing hist column PERF_HPP__PERIOD and newly added hist column PERF_HPP__PERIOD_BASELINE. Signed-off-by: Jiri Olsa Cc: Andi Kleen Cc: Corey Ashford Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Namhyung Kim Cc: Paul Mackerras Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1349448287-18919-6-git-send-email-jolsa@redhat.com Signed-off-by: Arnaldo Carvalho de Melo

perf diff: Add weighted diff computation way to compare hist entries

2012-10-05T17:10:42Z

Adding 'wdiff' as new computation way to compare hist entries. If specified the 'Weighted diff' column is displayed with value 'd' computed as: d = B->period * WEIGHT-A - A->period * WEIGHT-B - A/B being matching hist entry from first/second file specified (or perf.data/perf.data.old) respectively. - period being the hist entry period value - WEIGHT-A/WEIGHT-B being user suplied weights in the the '-c' option behind ':' separator like '-c wdiff:1,2'. Signed-off-by: Jiri Olsa Cc: Andi Kleen Cc: Corey Ashford Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Namhyung Kim Cc: Paul Mackerras Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1349448287-18919-5-git-send-email-jolsa@redhat.com Signed-off-by: Arnaldo Carvalho de Melo

perf diff: Add option to sort entries based on diff computation

2012-10-05T17:08:54Z

Adding support to sort hist entries based on the outcome of selected computation. It's now possible to specify '+' as a first character of '-c' option value to make such sort. Example: $ perf diff -c ratio -b # Event 'cache-misses' # # Baseline Ratio Shared Object Symbol # ........ .............. ................. ................................ # 19.64% 0.69 [kernel.kallsyms] [k] clear_page 0.30% 0.17 [kernel.kallsyms] [k] mm_alloc 0.04% 0.20 [kernel.kallsyms] [k] kmem_cache_alloc $ perf diff -c +ratio -b # Event 'cache-misses' # # Baseline Ratio Shared Object Symbol # ........ .............. ................. ................................ # 19.64% 0.69 [kernel.kallsyms] [k] clear_page 0.04% 0.20 [kernel.kallsyms] [k] kmem_cache_alloc 0.30% 0.17 [kernel.kallsyms] [k] mm_alloc Signed-off-by: Jiri Olsa Cc: Andi Kleen Cc: Corey Ashford Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Namhyung Kim Cc: Paul Mackerras Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1349448287-18919-4-git-send-email-jolsa@redhat.com Signed-off-by: Arnaldo Carvalho de Melo

perf diff: Add ratio computation way to compare hist entries

2012-10-05T17:06:54Z

Adding -c option to select computation method with the current 'Delta' computation as default. Current possible values are of this option are: 'delta' and 'ratio'. Adding 'ratio' as new computation way to compare hist entries. If specified the 'Ratio' column is displayed with value 'r' computed as: r = A->period / B->period with: - A/B being matching hist entry from first/second file specified (or perf.data/perf.data.old) respectively. - period being the hist entry period value Signed-off-by: Jiri Olsa Cc: Andi Kleen Cc: Corey Ashford Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Namhyung Kim Cc: Paul Mackerras Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1349448287-18919-3-git-send-email-jolsa@redhat.com Signed-off-by: Arnaldo Carvalho de Melo