perf report/annotate/script: Add option to specify a CPU range

Add an option to perf report/annotate/script to specify which
CPUs to operate on. This enables us to take a single system wide
profile and analyse each CPU (or group of CPUs) in isolation.

This was useful when profiling a multiprocess workload where the
bottleneck was on one CPU but this was hidden in the overall
profile. Per process and per thread breakdowns didn't help
because multiple processes were running on each CPU and no
single process consumed an entire CPU.

The patch converts the list of CPUs returned by cpu_map__new
into a bitmap for fast lookup. I wanted to use -C to be
consistent with perf top/record/stat, but unfortunately perf
report already uses -C <comms>.

 v2: Incorporate suggestions from David Ahern:
	- Added -c to perf script
	- Check that SAMPLE_CPU is set when -c is used
	- Update documentation

 v3: Create perf_session__cpu_bitmap()

Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: David Ahern <dsahern@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Link: http://lkml.kernel.org/r/20110704215750.11647eb9@kryten
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/tools/perf/Documentation/perf-annotate.txt b/tools/perf/Documentation/perf-annotate.txt
index 6f5a498608b292241e93dc9c498e8ce5f6a683cc..85c5f026930d336bc6b2d2658087134e11caa328 100644 (file)
--- a/tools/perf/Documentation/perf-annotate.txt
+++ b/tools/perf/Documentation/perf-annotate.txt
@@ -66,6 +66,12 @@ OPTIONS
        used. This interfaces starts by centering on the line with more
        samples, TAB/UNTAB cycles through the lines with more samples.
 
+-c::
+--cpu:: Only report samples for the list of CPUs provided. Multiple CPUs can
+       be provided as a comma-separated list with no space: 0,1. Ranges of
+       CPUs are specified with -: 0-2. Default is to report samples on all
+       CPUs.
+
 SEE ALSO
 --------
 linkperf:perf-record[1], linkperf:perf-report[1]

diff --git a/tools/perf/Documentation/perf-report.txt b/tools/perf/Documentation/perf-report.txt
index cfa8e513d0fb2fda8a123bba4451dc3d90e46754..04253c07d19a8620f185d13950816d514755440b 100644 (file)
--- a/tools/perf/Documentation/perf-report.txt
+++ b/tools/perf/Documentation/perf-report.txt
@@ -128,6 +128,12 @@ OPTIONS
 --symfs=<directory>::
         Look for files with symbols relative to this directory.
 
+-c::
+--cpu:: Only report samples for the list of CPUs provided. Multiple CPUs can
+       be provided as a comma-separated list with no space: 0,1. Ranges of
+       CPUs are specified with -: 0-2. Default is to report samples on all
+       CPUs.
+
 SEE ALSO
 --------
 linkperf:perf-stat[1]

diff --git a/tools/perf/Documentation/perf-script.txt b/tools/perf/Documentation/perf-script.txt
index c6068cb43f57a0b99605fb8bb0ed69d3168b5396..db017867d9e8ff363f19eb3744c1195ae1415d46 100644 (file)
--- a/tools/perf/Documentation/perf-script.txt
+++ b/tools/perf/Documentation/perf-script.txt
@@ -182,6 +182,12 @@ OPTIONS
 --hide-call-graph::
         When printing symbols do not display call chain.
 
+-c::
+--cpu:: Only report samples for the list of CPUs provided. Multiple CPUs can
+       be provided as a comma-separated list with no space: 0,1. Ranges of
+       CPUs are specified with -: 0-2. Default is to report samples on all
+       CPUs.
+
 SEE ALSO
 --------
 linkperf:perf-record[1], linkperf:perf-script-perl[1],

diff --git a/tools/perf/builtin-annotate.c b/tools/perf/builtin-annotate.c
index 7b139e1e7e869f9c11070012ac21bf13534d1d50..555aefd7fe0146eada9b45dfd366f68a6285f854 100644 (file)
--- a/tools/perf/builtin-annotate.c
+++ b/tools/perf/builtin-annotate.c
@@ -28,6 +28,8 @@
 #include "util/hist.h"
 #include "util/session.h"
 
+#include <linux/bitmap.h>
+
 static char            const *input_name = "perf.data";
 
 static bool            force, use_tui, use_stdio;
@@ -38,6 +40,9 @@ static bool           print_line;
 
 static const char *sym_hist_filter;
 
+static const char      *cpu_list;
+static DECLARE_BITMAP(cpu_bitmap, MAX_NR_CPUS);
+
 static int perf_evlist__add_sample(struct perf_evlist *evlist,
                                   struct perf_sample *sample,
                                   struct perf_evsel *evsel,
@@ -90,6 +95,9 @@ static int process_sample_event(union perf_event *event,
                return -1;
        }
 
+       if (cpu_list && !test_bit(sample->cpu, cpu_bitmap))
+               return 0;
+
        if (!al.filtered &&
            perf_evlist__add_sample(session->evlist, sample, evsel, &al)) {
                pr_warning("problem incrementing symbol count, "
@@ -177,6 +185,12 @@ static int __cmd_annotate(void)
        if (session == NULL)
                return -ENOMEM;
 
+       if (cpu_list) {
+               ret = perf_session__cpu_bitmap(session, cpu_list, cpu_bitmap);
+               if (ret)
+                       goto out_delete;
+       }
+
        ret = perf_session__process_events(session, &event_ops);
        if (ret)
                goto out_delete;
@@ -252,6 +266,7 @@ static const struct option options[] = {
                    "print matching source lines (may be slow)"),
        OPT_BOOLEAN('P', "full-paths", &full_paths,
                    "Don't shorten the displayed pathnames"),
+       OPT_STRING('c', "cpu", &cpu_list, "cpu", "list of cpus to profile"),
        OPT_END()
 };
 

diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index 5d43d0181d632bc60711e82fecb392d8b3d4ac7a..f854efda76869412210ede431f4844a5e386cd34 100644 (file)
--- a/tools/perf/builtin-report.c
+++ b/tools/perf/builtin-report.c
@@ -33,6 +33,8 @@
 #include "util/sort.h"
 #include "util/hist.h"
 
+#include <linux/bitmap.h>
+
 static char            const *input_name = "perf.data";
 
 static bool            force, use_tui, use_stdio;
@@ -49,6 +51,9 @@ static char           callchain_default_opt[] = "fractal,0.5,callee";
 static bool            inverted_callchain;
 static symbol_filter_t annotate_init;
 
+static const char      *cpu_list;
+static DECLARE_BITMAP(cpu_bitmap, MAX_NR_CPUS);
+
 static int perf_session__add_hist_entry(struct perf_session *session,
                                        struct addr_location *al,
                                        struct perf_sample *sample,
@@ -117,6 +122,9 @@ static int process_sample_event(union perf_event *event,
        if (al.filtered || (hide_unresolved && al.sym == NULL))
                return 0;
 
+       if (cpu_list && !test_bit(sample->cpu, cpu_bitmap))
+               return 0;
+
        if (al.map != NULL)
                al.map->dso->hit = 1;
 
@@ -263,6 +271,12 @@ static int __cmd_report(void)
        if (session == NULL)
                return -ENOMEM;
 
+       if (cpu_list) {
+               ret = perf_session__cpu_bitmap(session, cpu_list, cpu_bitmap);
+               if (ret)
+                       goto out_delete;
+       }
+
        if (show_threads)
                perf_read_values_init(&show_threads_values);
 
@@ -473,6 +487,7 @@ static const struct option options[] = {
                    "Only display entries resolved to a symbol"),
        OPT_STRING(0, "symfs", &symbol_conf.symfs, "directory",
                    "Look for files with symbols relative to this directory"),
+       OPT_STRING('c', "cpu", &cpu_list, "cpu", "list of cpus to profile"),
        OPT_END()
 };
 

diff --git a/tools/perf/builtin-script.c b/tools/perf/builtin-script.c
index 3056b45b3dd635d1b19fd71bf8e3b57a954cc22c..09024ec2ab2e97a478271c67dc29f40c5c242211 100644 (file)
--- a/tools/perf/builtin-script.c
+++ b/tools/perf/builtin-script.c
@@ -13,6 +13,7 @@
 #include "util/util.h"
 #include "util/evlist.h"
 #include "util/evsel.h"
+#include <linux/bitmap.h>
 
 static char const              *script_name;
 static char const              *generate_script_lang;
@@ -21,6 +22,8 @@ static u64                    last_timestamp;
 static u64                     nr_unordered;
 extern const struct option     record_options[];
 static bool                    no_callchain;
+static const char              *cpu_list;
+static DECLARE_BITMAP(cpu_bitmap, MAX_NR_CPUS);
 
 enum perf_output_field {
        PERF_OUTPUT_COMM            = 1U << 0,
@@ -453,6 +456,10 @@ static int process_sample_event(union perf_event *event,
                last_timestamp = sample->time;
                return 0;
        }
+
+       if (cpu_list && !test_bit(sample->cpu, cpu_bitmap))
+               return 0;
+
        scripting_ops->process_event(event, sample, evsel, session, thread);
 
        session->hists.stats.total_period += sample->period;
@@ -1075,6 +1082,7 @@ static const struct option options[] = {
        OPT_CALLBACK('f', "fields", NULL, "str",
                     "comma separated output fields prepend with 'type:'. Valid types: hw,sw,trace,raw. Fields: comm,tid,pid,time,cpu,event,trace,ip,sym,dso,addr",
                     parse_output_fields),
+       OPT_STRING('c', "cpu", &cpu_list, "cpu", "list of cpus to profile"),
 
        OPT_END()
 };
@@ -1255,6 +1263,11 @@ int cmd_script(int argc, const char **argv, const char *prefix __used)
        if (session == NULL)
                return -ENOMEM;
 
+       if (cpu_list) {
+               if (perf_session__cpu_bitmap(session, cpu_list, cpu_bitmap))
+                       return -1;
+       }
+
        if (!no_callchain)
                symbol_conf.use_callchain = true;
        else

diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index 558bcf99694935a706fd2d0e4dde914880918c7f..080e5336d89f54c6011553d027c12d598af0afb0 100644 (file)
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -12,6 +12,7 @@
 #include "session.h"
 #include "sort.h"
 #include "util.h"
+#include "cpumap.h"
 
 static int perf_session__open(struct perf_session *self, bool force)
 {
@@ -1282,3 +1283,40 @@ void perf_session__print_ip(union perf_event *event,
                }
        }
 }
+
+int perf_session__cpu_bitmap(struct perf_session *session,
+                            const char *cpu_list, unsigned long *cpu_bitmap)
+{
+       int i;
+       struct cpu_map *map;
+
+       for (i = 0; i < PERF_TYPE_MAX; ++i) {
+               struct perf_evsel *evsel;
+
+               evsel = perf_session__find_first_evtype(session, i);
+               if (!evsel)
+                       continue;
+
+               if (!(evsel->attr.sample_type & PERF_SAMPLE_CPU)) {
+                       pr_err("File does not contain CPU events. "
+                              "Remove -c option to proceed.\n");
+                       return -1;
+               }
+       }
+
+       map = cpu_map__new(cpu_list);
+
+       for (i = 0; i < map->nr; i++) {
+               int cpu = map->map[i];
+
+               if (cpu >= MAX_NR_CPUS) {
+                       pr_err("Requested CPU %d too large. "
+                              "Consider raising MAX_NR_CPUS\n", cpu);
+                       return -1;
+               }
+
+               set_bit(cpu, cpu_bitmap);
+       }
+
+       return 0;
+}

diff --git a/tools/perf/util/session.h b/tools/perf/util/session.h
index de4178d7bb7bb4fed28b06c87a4ad06fa7a01645..5de754f4b7f345a2f00165019396515738a22371 100644 (file)
--- a/tools/perf/util/session.h
+++ b/tools/perf/util/session.h
@@ -172,4 +172,7 @@ void perf_session__print_ip(union perf_event *event,
                                 struct perf_session *session,
                                 int print_sym, int print_dso);
 
+int perf_session__cpu_bitmap(struct perf_session *session,
+                            const char *cpu_list, unsigned long *cpu_bitmap);
+
 #endif /* __PERF_SESSION_H */