Commit 7248e308 authored by Alexandre Truong's avatar Alexandre Truong Committed by Arnaldo Carvalho de Melo
Browse files

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: default avatarJames Clark <james.clark@arm.com>
Signed-off-by: default avatarAlexandre Truong <alexandre.truong@arm.com>
Acked-by: default avatarJiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Will Deacon <will@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org
Link: https://lore.kernel.org/r/20211217154521.80603-2-german.gomez@arm.com


Signed-off-by: default avatarGerman Gomez <german.gomez@arm.com>
Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent f8464e08

tools/perf/arch/arm64/util/machine.c

+7 −0
Original line number Diff line number Diff line
@@ -5,6 +5,8 @@ 
#include <string.h>

#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;

}

tools/perf/builtin-record.c

+8 −0
Original line number Diff line number Diff line
@@ -2267,6 +2267,10 @@ static int record__parse_mmap_pages(const struct option *opt, 
	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);

tools/perf/util/callchain.h

+2 −0
Original line number Diff line number Diff line
@@ -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,