From a1a8bed32de197801bb861fbf13cd01496df3e05 Mon Sep 17 00:00:00 2001 From: Jin Yao Date: Mon, 24 Jul 2017 19:09:07 +0800 Subject: [PATCH] perf report: Tag branch type/flag on "to" and tag cycles on "from" Current --branch-history LBR annotation displays confused data. For example, each cycles report is duplicated on both "from" and "to" entries. For example: perf report --branch-history --no-children --stdio --2.32%--main div.c:39 (COND_BWD CROSS_2M predicted:49.7% cycles:1) main div.c:44 (predicted:49.7% cycles:1) main div.c:42 (RET CROSS_2M cycles:2) compute_flag div.c:28 (cycles:2) compute_flag div.c:27 (RET CROSS_2M cycles:1) rand rand.c:28 (cycles:1) rand rand.c:28 (RET CROSS_2M cycles:1) __random random.c:298 (cycles:1) __random random.c:297 (COND_BWD CROSS_2M cycles:1) __random random.c:295 (cycles:1) __random random.c:295 (COND_BWD CROSS_2M cycles:1) __random random.c:295 (cycles:1) __random random.c:295 (RET CROSS_2M cycles:9) The cycles should be tagged only on the "from". It's for the code block that ends with "from", not for "to". Another issue is the "predicted:49.7%" is duplicated too (tag on both "from" and "to"). This patch tags the branch type/flag on "to" and tag the cycles on "from". For example: --2.32%--main div.c:39 (COND_BWD CROSS_2M predicted:49.7%) main div.c:44 (cycles:1) main div.c:42 (RET CROSS_2M) compute_flag div.c:28 (cycles:2) compute_flag div.c:27 (RET CROSS_2M) rand rand.c:28 (cycles:1) rand rand.c:28 (RET CROSS_2M) __random random.c:298 (cycles:1) __random random.c:297 (COND_BWD CROSS_2M) __random random.c:295 (cycles:1) __random random.c:295 (COND_BWD CROSS_2M) __random random.c:295 (cycles:1) __random random.c:295 (RET CROSS_2M) | --2.23%--__random_r random_r.c:392 (cycles:9) In this example, The "main div.c:39 (COND_BWD CROSS_2M predicted:49.7%)" is "to" of branch and "main div.c:44 (cycles:1)" is "from" of branch. It should be easier for understanding than before. Signed-off-by: Yao Jin Reviewed-by: Andi Kleen Cc: Alexander Shishkin Cc: Jiri Olsa Cc: Kan Liang Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1500894547-18411-1-git-send-email-yao.jin@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/branch.h | 11 +-- tools/perf/util/callchain.c | 136 ++++++++++++++++++++++++++---------- 2 files changed, 105 insertions(+), 42 deletions(-) diff --git a/tools/perf/util/branch.h b/tools/perf/util/branch.h index 686f2b65ba84..1e3c7c5cdc63 100644 --- a/tools/perf/util/branch.h +++ b/tools/perf/util/branch.h @@ -5,11 +5,12 @@ #include "../perf.h" struct branch_type_stat { - u64 counts[PERF_BR_MAX]; - u64 cond_fwd; - u64 cond_bwd; - u64 cross_4k; - u64 cross_2m; + bool branch_to; + u64 counts[PERF_BR_MAX]; + u64 cond_fwd; + u64 cond_bwd; + u64 cross_4k; + u64 cross_2m; }; struct branch_flags; diff --git a/tools/perf/util/callchain.c b/tools/perf/util/callchain.c index 1f536418dfb5..f320b0777e0d 100644 --- a/tools/perf/util/callchain.c +++ b/tools/perf/util/callchain.c @@ -563,20 +563,33 @@ fill_node(struct callchain_node *node, struct callchain_cursor *cursor) if (cursor_node->branch) { call->branch_count = 1; - if (cursor_node->branch_flags.predicted) - call->predicted_count = 1; + if (cursor_node->branch_from) { + /* + * branch_from is set with value somewhere else + * to imply it's "to" of a branch. + */ + call->brtype_stat.branch_to = true; - if (cursor_node->branch_flags.abort) - call->abort_count = 1; + if (cursor_node->branch_flags.predicted) + call->predicted_count = 1; - call->cycles_count = cursor_node->branch_flags.cycles; - call->iter_count = cursor_node->nr_loop_iter; - call->samples_count = cursor_node->samples; + if (cursor_node->branch_flags.abort) + call->abort_count = 1; - branch_type_count(&call->brtype_stat, - &cursor_node->branch_flags, - cursor_node->branch_from, - cursor_node->ip); + branch_type_count(&call->brtype_stat, + &cursor_node->branch_flags, + cursor_node->branch_from, + cursor_node->ip); + } else { + /* + * It's "from" of a branch + */ + call->brtype_stat.branch_to = false; + call->cycles_count = + cursor_node->branch_flags.cycles; + call->iter_count = cursor_node->nr_loop_iter; + call->samples_count = cursor_node->samples; + } } list_add_tail(&call->list, &node->val); @@ -685,20 +698,32 @@ static enum match_result match_chain(struct callchain_cursor_node *node, if (node->branch) { cnode->branch_count++; - if (node->branch_flags.predicted) - cnode->predicted_count++; + if (node->branch_from) { + /* + * It's "to" of a branch + */ + cnode->brtype_stat.branch_to = true; - if (node->branch_flags.abort) - cnode->abort_count++; + if (node->branch_flags.predicted) + cnode->predicted_count++; - cnode->cycles_count += node->branch_flags.cycles; - cnode->iter_count += node->nr_loop_iter; - cnode->samples_count += node->samples; + if (node->branch_flags.abort) + cnode->abort_count++; - branch_type_count(&cnode->brtype_stat, - &node->branch_flags, - node->branch_from, - node->ip); + branch_type_count(&cnode->brtype_stat, + &node->branch_flags, + node->branch_from, + node->ip); + } else { + /* + * It's "from" of a branch + */ + cnode->brtype_stat.branch_to = false; + cnode->cycles_count += + node->branch_flags.cycles; + cnode->iter_count += node->nr_loop_iter; + cnode->samples_count += node->samples; + } } return MATCH_EQ; @@ -1236,27 +1261,26 @@ static int count_pri64_printf(int idx, const char *str, u64 value, char *bf, int return printed; } -static int count_float_printf(int idx, const char *str, float value, char *bf, int bfsize) +static int count_float_printf(int idx, const char *str, float value, + char *bf, int bfsize, float threshold) { int printed; + if (threshold != 0.0 && value < threshold) + return 0; + printed = scnprintf(bf, bfsize, "%s%s:%.1f%%", (idx) ? " " : " (", str, value); return printed; } -static int counts_str_build(char *bf, int bfsize, - u64 branch_count, u64 predicted_count, - u64 abort_count, u64 cycles_count, - u64 iter_count, u64 samples_count, - struct branch_type_stat *brtype_stat) +static int branch_to_str(char *bf, int bfsize, + u64 branch_count, u64 predicted_count, + u64 abort_count, + struct branch_type_stat *brtype_stat) { - u64 cycles; int printed, i = 0; - if (branch_count == 0) - return scnprintf(bf, bfsize, " (calltrace)"); - printed = branch_type_str(brtype_stat, bf, bfsize); if (printed) i++; @@ -1264,15 +1288,29 @@ static int counts_str_build(char *bf, int bfsize, if (predicted_count < branch_count) { printed += count_float_printf(i++, "predicted", predicted_count * 100.0 / branch_count, - bf + printed, bfsize - printed); + bf + printed, bfsize - printed, 0.0); } if (abort_count) { printed += count_float_printf(i++, "abort", abort_count * 100.0 / branch_count, - bf + printed, bfsize - printed); + bf + printed, bfsize - printed, 0.1); } + if (i) + printed += scnprintf(bf + printed, bfsize - printed, ")"); + + return printed; +} + +static int branch_from_str(char *bf, int bfsize, + u64 branch_count, + u64 cycles_count, u64 iter_count, + u64 samples_count) +{ + int printed = 0, i = 0; + u64 cycles; + cycles = cycles_count / branch_count; if (cycles) { printed += count_pri64_printf(i++, "cycles", @@ -1287,10 +1325,34 @@ static int counts_str_build(char *bf, int bfsize, } if (i) - return scnprintf(bf + printed, bfsize - printed, ")"); + printed += scnprintf(bf + printed, bfsize - printed, ")"); - bf[0] = 0; - return 0; + return printed; +} + +static int counts_str_build(char *bf, int bfsize, + u64 branch_count, u64 predicted_count, + u64 abort_count, u64 cycles_count, + u64 iter_count, u64 samples_count, + struct branch_type_stat *brtype_stat) +{ + int printed; + + if (branch_count == 0) + return scnprintf(bf, bfsize, " (calltrace)"); + + if (brtype_stat->branch_to) { + printed = branch_to_str(bf, bfsize, branch_count, + predicted_count, abort_count, brtype_stat); + } else { + printed = branch_from_str(bf, bfsize, branch_count, + cycles_count, iter_count, samples_count); + } + + if (!printed) + bf[0] = 0; + + return printed; } static int callchain_counts_printf(FILE *fp, char *bf, int bfsize,