From fe176085a4d45fb241c04beea872ecbb8bef6a55 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Thu, 19 May 2016 11:34:06 -0300 Subject: [PATCH] perf tools: Fix usage of max_stack sysctl We cannot limit processing stacks from the current value of the sysctl, as we may be processing perf.data files, possibly from other machines. Instead use the old PERF_MAX_STACK_DEPTH, the sysctl default, that can be overriden using --max-stack or equivalent. Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Alexei Starovoitov Cc: Brendan Gregg Cc: David Ahern Cc: Frederic Weisbecker Cc: He Kuang Cc: Jiri Olsa Cc: Masami Hiramatsu Cc: Milian Wolff Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Stephane Eranian Cc: Thomas Gleixner Cc: Vince Weaver Cc: Wang Nan Cc: Zefan Li Fixes: 4cb93446c587 ("perf tools: Set the maximum allowed stack from /proc/sys/kernel/perf_event_max_stack") Link: http://lkml.kernel.org/n/tip-eqeutsr7n7wy0c36z24ytvii@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/Documentation/perf-report.txt | 2 +- tools/perf/Documentation/perf-script.txt | 2 +- tools/perf/Documentation/perf-trace.txt | 3 ++- tools/perf/builtin-report.c | 2 +- tools/perf/builtin-script.c | 2 -- tools/perf/builtin-trace.c | 2 +- tools/perf/util/db-export.c | 3 +-- tools/perf/util/scripting-engines/trace-event-perl.c | 3 +-- 8 files changed, 8 insertions(+), 11 deletions(-) diff --git a/tools/perf/Documentation/perf-report.txt b/tools/perf/Documentation/perf-report.txt index ebaf849..496d42c 100644 --- a/tools/perf/Documentation/perf-report.txt +++ b/tools/perf/Documentation/perf-report.txt @@ -248,7 +248,7 @@ OPTIONS Note that when using the --itrace option the synthesized callchain size will override this value if the synthesized callchain size is bigger. - Default: /proc/sys/kernel/perf_event_max_stack when present, 127 otherwise. + Default: 127 -G:: --inverted:: diff --git a/tools/perf/Documentation/perf-script.txt b/tools/perf/Documentation/perf-script.txt index a856a10..4fc44c7 100644 --- a/tools/perf/Documentation/perf-script.txt +++ b/tools/perf/Documentation/perf-script.txt @@ -267,7 +267,7 @@ include::itrace.txt[] Note that when using the --itrace option the synthesized callchain size will override this value if the synthesized callchain size is bigger. - Default: /proc/sys/kernel/perf_event_max_stack when present, 127 otherwise. + Default: 127 --ns:: Use 9 decimal places when displaying time (i.e. show the nanoseconds) diff --git a/tools/perf/Documentation/perf-trace.txt b/tools/perf/Documentation/perf-trace.txt index 6afe201..1ab0782 100644 --- a/tools/perf/Documentation/perf-trace.txt +++ b/tools/perf/Documentation/perf-trace.txt @@ -143,7 +143,8 @@ the thread executes on the designated CPUs. Default is to monitor all CPUs. Implies '--call-graph dwarf' when --call-graph not present on the command line, on systems where DWARF unwinding was built in. - Default: /proc/sys/kernel/perf_event_max_stack when present, 127 otherwise. + Default: /proc/sys/kernel/perf_event_max_stack when present for + live sessions (without --input/-i), 127 otherwise. --min-stack:: Set the stack depth limit when parsing the callchain, anything diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c index 87d40e3..9bc71c6 100644 --- a/tools/perf/builtin-report.c +++ b/tools/perf/builtin-report.c @@ -691,7 +691,7 @@ int cmd_report(int argc, const char **argv, const char *prefix __maybe_unused) .ordered_events = true, .ordering_requires_timestamps = true, }, - .max_stack = sysctl_perf_event_max_stack, + .max_stack = PERF_MAX_STACK_DEPTH, .pretty_printing_style = "normal", .socket_filter = -1, }; diff --git a/tools/perf/builtin-script.c b/tools/perf/builtin-script.c index efca816..0a83f4b 100644 --- a/tools/perf/builtin-script.c +++ b/tools/perf/builtin-script.c @@ -2067,8 +2067,6 @@ int cmd_script(int argc, const char **argv, const char *prefix __maybe_unused) NULL }; - scripting_max_stack = sysctl_perf_event_max_stack; - setup_scripting(); argc = parse_options_subcommand(argc, argv, options, script_subcommands, script_usage, diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c index a2f3aa09..7401de7 100644 --- a/tools/perf/builtin-trace.c +++ b/tools/perf/builtin-trace.c @@ -2905,7 +2905,7 @@ int cmd_trace(int argc, const char **argv, const char *prefix __maybe_unused) mmap_pages_user_set = false; if (trace.max_stack == UINT_MAX) { - trace.max_stack = sysctl_perf_event_max_stack; + trace.max_stack = input_name ? PERF_MAX_STACK_DEPTH : sysctl_perf_event_max_stack; max_stack_user_set = false; } diff --git a/tools/perf/util/db-export.c b/tools/perf/util/db-export.c index 8d96c80..c9a6dc1 100644 --- a/tools/perf/util/db-export.c +++ b/tools/perf/util/db-export.c @@ -298,8 +298,7 @@ static struct call_path *call_path_from_sample(struct db_export *dbe, */ callchain_param.order = ORDER_CALLER; err = thread__resolve_callchain(thread, &callchain_cursor, evsel, - sample, NULL, NULL, - sysctl_perf_event_max_stack); + sample, NULL, NULL, PERF_MAX_STACK_DEPTH); if (err) { callchain_param.order = saved_order; return NULL; diff --git a/tools/perf/util/scripting-engines/trace-event-perl.c b/tools/perf/util/scripting-engines/trace-event-perl.c index 62c7f69..5d1eb1c 100644 --- a/tools/perf/util/scripting-engines/trace-event-perl.c +++ b/tools/perf/util/scripting-engines/trace-event-perl.c @@ -264,8 +264,7 @@ static SV *perl_process_callchain(struct perf_sample *sample, goto exit; if (thread__resolve_callchain(al->thread, &callchain_cursor, evsel, - sample, NULL, NULL, - sysctl_perf_event_max_stack) != 0) { + sample, NULL, NULL, scripting_max_stack) != 0) { pr_err("Failed to resolve callchain. Skipping\n"); goto exit; } -- 2.7.4