[tip:perf/urgent] perf tools: Fix usage of max_stack sysctl
From: tip-bot for Arnaldo Carvalho de Melo
Date: Fri May 20 2016 - 13:46:04 EST
Commit-ID: fe176085a4d45fb241c04beea872ecbb8bef6a55
Gitweb: http://git.kernel.org/tip/fe176085a4d45fb241c04beea872ecbb8bef6a55
Author: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
AuthorDate: Thu, 19 May 2016 11:34:06 -0300
Committer: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitDate: Fri, 20 May 2016 11:43:56 -0300
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 <adrian.hunter@xxxxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: Alexei Starovoitov <ast@xxxxxxxxxx>
Cc: Brendan Gregg <brendan.d.gregg@xxxxxxxxx>
Cc: David Ahern <dsahern@xxxxxxxxx>
Cc: Frederic Weisbecker <fweisbec@xxxxxxxxx>
Cc: He Kuang <hekuang@xxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Cc: Milian Wolff <milian.wolff@xxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Stephane Eranian <eranian@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Vince Weaver <vincent.weaver@xxxxxxxxx>
Cc: Wang Nan <wangnan0@xxxxxxxxxx>
Cc: Zefan Li <lizefan@xxxxxxxxxx>
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@xxxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
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;
}