From 7248e308a57587615431b83689cd57e957815bfc Mon Sep 17 00:00:00 2001 From: Alexandre Truong Date: Fri, 17 Dec 2021 15:45:15 +0000 Subject: [PATCH] perf tools: Record ARM64 LR register automatically On ARM64, automatically record the link register if the frame pointer mode is on. It will be used to do a dwarf unwind to find the caller of the leaf frame if the frame pointer was omitted. Reviewed-by: James Clark Signed-off-by: Alexandre Truong Acked-by: Jiri Olsa Cc: Alexander Shishkin Cc: John Garry Cc: Leo Yan Cc: Mark Rutland Cc: Mathieu Poirier Cc: Namhyung Kim Cc: Will Deacon Cc: linux-arm-kernel@lists.infradead.org Link: https://lore.kernel.org/r/20211217154521.80603-2-german.gomez@arm.com Signed-off-by: German Gomez Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/arch/arm64/util/machine.c | 7 +++++++ tools/perf/builtin-record.c | 8 ++++++++ tools/perf/util/callchain.h | 2 ++ 3 files changed, 17 insertions(+) diff --git a/tools/perf/arch/arm64/util/machine.c b/tools/perf/arch/arm64/util/machine.c index 7e7714290a87..d2ce31e28cd7 100644 --- a/tools/perf/arch/arm64/util/machine.c +++ b/tools/perf/arch/arm64/util/machine.c @@ -5,6 +5,8 @@ #include #include "debug.h" #include "symbol.h" +#include "callchain.h" +#include "record.h" /* On arm64, kernel text segment starts at high memory address, * for example 0xffff 0000 8xxx xxxx. Modules start at a low memory @@ -26,3 +28,8 @@ void arch__symbols__fixup_end(struct symbol *p, struct symbol *c) p->end = c->start; pr_debug4("%s sym:%s end:%#" PRIx64 "\n", __func__, p->name, p->end); } + +void arch__add_leaf_frame_record_opts(struct record_opts *opts) +{ + opts->sample_user_regs |= sample_reg_masks[PERF_REG_ARM64_LR].mask; +} diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index 0338b813585a..6ac2160913ea 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -2267,6 +2267,10 @@ out_free: return ret; } +void __weak arch__add_leaf_frame_record_opts(struct record_opts *opts __maybe_unused) +{ +} + static int parse_control_option(const struct option *opt, const char *str, int unset __maybe_unused) @@ -2898,6 +2902,10 @@ int cmd_record(int argc, const char **argv) } rec->opts.target.hybrid = perf_pmu__has_hybrid(); + + if (callchain_param.enabled && callchain_param.record_mode == CALLCHAIN_FP) + arch__add_leaf_frame_record_opts(&rec->opts); + err = -ENOMEM; if (evlist__create_maps(rec->evlist, &rec->opts.target) < 0) usage_with_options(record_usage, record_options); diff --git a/tools/perf/util/callchain.h b/tools/perf/util/callchain.h index 5824134f983b..77fba053c677 100644 --- a/tools/perf/util/callchain.h +++ b/tools/perf/util/callchain.h @@ -280,6 +280,8 @@ static inline int arch_skip_callchain_idx(struct thread *thread __maybe_unused, } #endif +void arch__add_leaf_frame_record_opts(struct record_opts *opts); + char *callchain_list__sym_name(struct callchain_list *cl, char *bf, size_t bfsize, bool show_dso); char *callchain_node__scnprintf_value(struct callchain_node *node,