From 37676af15c8d5a9689c9d1220d2a27d510cbe238 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Wed, 13 Nov 2013 17:40:36 -0300 Subject: [PATCH] perf symbols: Limit max callchain using max_stack on DWARF unwinding too It was affecting only frame-pointer (fp) based callchain processing. Usage example: perf top --call-graph dwarf,1024 --max-stack 2 Works for any tool that does callchain resolving and provides a --max-stack option. Cc: Adrian Hunter Cc: David Ahern Cc: Frederic Weisbecker Cc: Jiri Olsa Cc: Mike Galbraith Cc: Namhyung Kim Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Stephane Eranian Cc: Waiman Long Link: http://lkml.kernel.org/n/tip-eu45v8s3tq9ruay8tpfyon79@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/machine.c | 2 +- tools/perf/util/unwind.c | 9 +++++---- tools/perf/util/unwind.h | 5 +++-- 3 files changed, 9 insertions(+), 7 deletions(-) diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c index 0393912d8033..84cdb072ac83 100644 --- a/tools/perf/util/machine.c +++ b/tools/perf/util/machine.c @@ -1368,7 +1368,7 @@ int machine__resolve_callchain(struct machine *machine, return unwind__get_entries(unwind_entry, &callchain_cursor, machine, thread, evsel->attr.sample_regs_user, - sample); + sample, max_stack); } diff --git a/tools/perf/util/unwind.c b/tools/perf/util/unwind.c index 5390d0b8862a..0efd5393de85 100644 --- a/tools/perf/util/unwind.c +++ b/tools/perf/util/unwind.c @@ -559,7 +559,7 @@ static unw_accessors_t accessors = { }; static int get_entries(struct unwind_info *ui, unwind_entry_cb_t cb, - void *arg) + void *arg, int max_stack) { unw_addr_space_t addr_space; unw_cursor_t c; @@ -575,7 +575,7 @@ static int get_entries(struct unwind_info *ui, unwind_entry_cb_t cb, if (ret) display_error(ret); - while (!ret && (unw_step(&c) > 0)) { + while (!ret && (unw_step(&c) > 0) && max_stack--) { unw_word_t ip; unw_get_reg(&c, UNW_REG_IP, &ip); @@ -588,7 +588,8 @@ static int get_entries(struct unwind_info *ui, unwind_entry_cb_t cb, int unwind__get_entries(unwind_entry_cb_t cb, void *arg, struct machine *machine, struct thread *thread, - u64 sample_uregs, struct perf_sample *data) + u64 sample_uregs, struct perf_sample *data, + int max_stack) { unw_word_t ip; struct unwind_info ui = { @@ -610,5 +611,5 @@ int unwind__get_entries(unwind_entry_cb_t cb, void *arg, if (ret) return -ENOMEM; - return get_entries(&ui, cb, arg); + return get_entries(&ui, cb, arg, max_stack); } diff --git a/tools/perf/util/unwind.h b/tools/perf/util/unwind.h index ec0c71a2ca2e..d5966f49e22c 100644 --- a/tools/perf/util/unwind.h +++ b/tools/perf/util/unwind.h @@ -18,7 +18,7 @@ int unwind__get_entries(unwind_entry_cb_t cb, void *arg, struct machine *machine, struct thread *thread, u64 sample_uregs, - struct perf_sample *data); + struct perf_sample *data, int max_stack); int unwind__arch_reg_id(int regnum); #else static inline int @@ -27,7 +27,8 @@ unwind__get_entries(unwind_entry_cb_t cb __maybe_unused, struct machine *machine __maybe_unused, struct thread *thread __maybe_unused, u64 sample_uregs __maybe_unused, - struct perf_sample *data __maybe_unused) + struct perf_sample *data __maybe_unused, + int max_stack __maybe_unused) { return 0; } -- 2.20.1