From 961224db0470c9be08ef64b14913452a5e865d00 Mon Sep 17 00:00:00 2001 From: Adrian Hunter Date: Sat, 16 May 2020 15:35:48 +0300 Subject: [PATCH] perf intel-pt: Use allocated branch stack for PEBS sample To avoid having struct branch_stack as a non-last structure member, use allocated branch stack for PEBS sample. Signed-off-by: Adrian Hunter Acked-by: Gustavo A. R. Silva Cc: Alexander Shishkin Cc: Ian Rogers Cc: Jiri Olsa Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Link: http://lore.kernel.org/lkml/2540ed9a-89f1-6d59-10c9-a66cc90db5d2@intel.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/intel-pt.c | 31 +++++++++++++------------------ 1 file changed, 13 insertions(+), 18 deletions(-) diff --git a/tools/perf/util/intel-pt.c b/tools/perf/util/intel-pt.c index f17b1e7..e4dd8bf 100644 --- a/tools/perf/util/intel-pt.c +++ b/tools/perf/util/intel-pt.c @@ -913,11 +913,11 @@ static void intel_pt_add_callchain(struct intel_pt *pt, sample->callchain = pt->chain; } -static struct branch_stack *intel_pt_alloc_br_stack(struct intel_pt *pt) +static struct branch_stack *intel_pt_alloc_br_stack(unsigned int entry_cnt) { size_t sz = sizeof(struct branch_stack); - sz += pt->br_stack_sz * sizeof(struct branch_entry); + sz += entry_cnt * sizeof(struct branch_entry); return zalloc(sz); } @@ -930,7 +930,7 @@ static int intel_pt_br_stack_init(struct intel_pt *pt) evsel->synth_sample_type |= PERF_SAMPLE_BRANCH_STACK; } - pt->br_stack = intel_pt_alloc_br_stack(pt); + pt->br_stack = intel_pt_alloc_br_stack(pt->br_stack_sz); if (!pt->br_stack) return -ENOMEM; @@ -951,6 +951,9 @@ static void intel_pt_add_br_stack(struct intel_pt *pt, sample->branch_stack = pt->br_stack; } +/* INTEL_PT_LBR_0, INTEL_PT_LBR_1 and INTEL_PT_LBR_2 */ +#define LBRS_MAX (INTEL_PT_BLK_ITEM_ID_CNT * 3U) + static struct intel_pt_queue *intel_pt_alloc_queue(struct intel_pt *pt, unsigned int queue_nr) { @@ -968,8 +971,10 @@ static struct intel_pt_queue *intel_pt_alloc_queue(struct intel_pt *pt, goto out_free; } - if (pt->synth_opts.last_branch) { - ptq->last_branch = intel_pt_alloc_br_stack(pt); + if (pt->synth_opts.last_branch || pt->synth_opts.other_events) { + unsigned int entry_cnt = max(LBRS_MAX, pt->br_stack_sz); + + ptq->last_branch = intel_pt_alloc_br_stack(entry_cnt); if (!ptq->last_branch) goto out_free; } @@ -1720,9 +1725,6 @@ static void intel_pt_add_lbrs(struct branch_stack *br_stack, } } -/* INTEL_PT_LBR_0, INTEL_PT_LBR_1 and INTEL_PT_LBR_2 */ -#define LBRS_MAX (INTEL_PT_BLK_ITEM_ID_CNT * 3) - static int intel_pt_synth_pebs_sample(struct intel_pt_queue *ptq) { const struct intel_pt_blk_items *items = &ptq->state->items; @@ -1798,25 +1800,18 @@ static int intel_pt_synth_pebs_sample(struct intel_pt_queue *ptq) } if (sample_type & PERF_SAMPLE_BRANCH_STACK) { - struct { - struct branch_stack br_stack; - struct branch_entry entries[LBRS_MAX]; - } br; - if (items->mask[INTEL_PT_LBR_0_POS] || items->mask[INTEL_PT_LBR_1_POS] || items->mask[INTEL_PT_LBR_2_POS]) { - intel_pt_add_lbrs(&br.br_stack, items); - sample.branch_stack = &br.br_stack; + intel_pt_add_lbrs(ptq->last_branch, items); } else if (pt->synth_opts.last_branch) { thread_stack__br_sample(ptq->thread, ptq->cpu, ptq->last_branch, pt->br_stack_sz); - sample.branch_stack = ptq->last_branch; } else { - br.br_stack.nr = 0; - sample.branch_stack = &br.br_stack; + ptq->last_branch->nr = 0; } + sample.branch_stack = ptq->last_branch; } if (sample_type & PERF_SAMPLE_ADDR && items->has_mem_access_address) -- 2.7.4