perf report: Document '--call-graph' for optional print_limit argument

The '--call-graph' command line option can receive undocumented optional
print_limit argument. Besides, use strtoul() to parse the option since
its type is u32.

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1323703017-6060-2-git-send-email-namhyung@gmail.com
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/Documentation/perf-report.txt b/tools/perf/Documentation/perf-report.txt
index dc85392..35af0dc 100644 (file)
--- a/tools/perf/Documentation/perf-report.txt
+++ b/tools/perf/Documentation/perf-report.txt
@@ -80,9 +80,10 @@ OPTIONS
 --dump-raw-trace::
         Dump raw trace in ASCII.
 
--g [type,min,order]::
+-g [type,min[,limit],order]::
 --call-graph::
-        Display call chains using type, min percent threshold and order.
+        Display call chains using type, min percent threshold, optional print
+       limit and order.
        type can be either:
        - flat: single column, linear exposure of call chains.
        - graph: use a graph tree, displaying absolute overhead rates.

diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index ece7c5d..b2654c9 100644 (file)
--- a/tools/perf/builtin-report.c
+++ b/tools/perf/builtin-report.c
@@ -407,7 +407,7 @@ parse_callchain_opt(const struct option *opt, const char *arg, int unset)
                goto setup;
 
        if (tok2[0] != 'c') {
-               callchain_param.print_limit = strtod(tok2, &endptr);
+               callchain_param.print_limit = strtoul(tok2, &endptr, 0);
                tok2 = strtok(NULL, ",");
                if (!tok2)
                        goto setup;
@@ -485,8 +485,8 @@ int cmd_report(int argc, const char **argv, const char *prefix __used)
                   "regex filter to identify parent, see: '--sort parent'"),
        OPT_BOOLEAN('x', "exclude-other", &symbol_conf.exclude_other,
                    "Only display entries with parent-match"),
-       OPT_CALLBACK_DEFAULT('g', "call-graph", &report, "output_type,min_percent, call_order",
-                    "Display callchains using output_type (graph, flat, fractal, or none) , min percent threshold and callchain order. "
+       OPT_CALLBACK_DEFAULT('g', "call-graph", &report, "output_type,min_percent[,print_limit],call_order",
+                    "Display callchains using output_type (graph, flat, fractal, or none) , min percent threshold, optional print limit and callchain order. "
                     "Default: fractal,0.5,callee", &parse_callchain_opt, callchain_default_opt),
        OPT_BOOLEAN('G', "inverted", &report.inverted_callchain,
                    "alias for inverted call graph"),