From dc6d2bc2d893a878e7b58578ff01b4738708deb4 Mon Sep 17 00:00:00 2001 From: Ian Rogers Date: Mon, 13 Jan 2025 11:43:45 -0800 Subject: perf sample: Make user_regs and intr_regs optional The struct dump_regs contains 512 bytes of cache_regs, meaning the two values in perf_sample contribute 1088 bytes of its total 1384 bytes size. Initializing this much memory has a cost reported by Tavian Barnes as about 2.5% when running `perf script --itrace=i0`: https://lore.kernel.org/lkml/d841b97b3ad2ca8bcab07e4293375fb7c32dfce7.1736618095.git.tavianator@tavianator.com/ Adrian Hunter replied that the zero initialization was necessary and couldn't simply be removed. This patch aims to strike a middle ground of still zeroing the perf_sample, but removing 79% of its size by make user_regs and intr_regs optional pointers to zalloc-ed memory. To support the allocation accessors are created for user_regs and intr_regs. To support correct cleanup perf_sample__init and perf_sample__exit functions are created and added throughout the code base. Signed-off-by: Ian Rogers Link: https://lore.kernel.org/r/20250113194345.1537821-1-irogers@google.com Signed-off-by: Namhyung Kim --- tools/perf/util/auxtrace.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) (limited to 'tools/perf/util/auxtrace.c') diff --git a/tools/perf/util/auxtrace.c b/tools/perf/util/auxtrace.c index 4d1633d87eff..03211c2623de 100644 --- a/tools/perf/util/auxtrace.c +++ b/tools/perf/util/auxtrace.c @@ -1173,16 +1173,19 @@ static int auxtrace_queue_data_cb(struct perf_session *session, if (!qd->samples || event->header.type != PERF_RECORD_SAMPLE) return 0; + perf_sample__init(&sample, /*all=*/false); err = evlist__parse_sample(session->evlist, event, &sample); if (err) - return err; - - if (!sample.aux_sample.size) - return 0; + goto out; - offset += sample.aux_sample.data - (void *)event; + if (sample.aux_sample.size) { + offset += sample.aux_sample.data - (void *)event; - return session->auxtrace->queue_data(session, &sample, NULL, offset); + err = session->auxtrace->queue_data(session, &sample, NULL, offset); + } +out: + perf_sample__exit(&sample); + return err; } int auxtrace_queue_data(struct perf_session *session, bool samples, bool events) -- cgit v1.2.3