perf time-utils: Refactor time range parsing code

Jiri points out that we don't need any time checking and time string
parsing if the --time option is not set. That makes sense.

This patch refactors the time range parsing code, move the duplicated
code from perf report and perf script to time_utils and check if --time
option is set before parsing the time string. This patch is no logic
change expected. So the usage of --time is same as before.

For example:

Select the first and second 10% time slices:
  perf report --time 10%/1,10%/2
  perf script --time 10%/1,10%/2

Select the slices from 0% to 10% and from 30% to 40%:
  perf report --time 0%-10%,30%-40%
  perf script --time 0%-10%,30%-40%

Select the time slices from timestamp 3971 to 3973
  perf report --time 3971,3973
  perf script --time 3971,3973

Committer testing:

Using the above examples, check before and after to see if it remains
the same:

  $ perf record -F 10000 -- find . -name "*.[ch]" -exec cat {} + > /dev/null
  [ perf record: Woken up 3 times to write data ]
  [ perf record: Captured and wrote 1.626 MB perf.data (42392 samples) ]
  $
  $ perf report --time 10%/1,10%/2 > /tmp/report.before.1
  $ perf script --time 10%/1,10%/2 > /tmp/script.before.1
  $ perf report --time 0%-10%,30%-40% > /tmp/report.before.2
  $ perf script --time 0%-10%,30%-40% > /tmp/script.before.2
  $ perf report --time 180457.375844,180457.377717 > /tmp/report.before.3
  $ perf script --time 180457.375844,180457.377717 > /tmp/script.before.3

For example, the 3rd test produces this slice:

  $ cat /tmp/script.before.3
        cat  3147 180457.375844:   2143 cycles:uppp:      7f79362590d9 cfree@GLIBC_2.2.5+0x9 (/usr/lib64/libc-2.28.so)
        cat  3147 180457.375986:   2245 cycles:uppp:      558b70f3d86e [unknown] (/usr/bin/cat)
        cat  3147 180457.376012:   2164 cycles:uppp:      7f7936257430 _int_malloc+0x8c0 (/usr/lib64/libc-2.28.so)
        cat  3147 180457.376140:   2921 cycles:uppp:      558b70f3a554 [unknown] (/usr/bin/cat)
        cat  3147 180457.376296:   2844 cycles:uppp:      7f7936258abe malloc+0x4e (/usr/lib64/libc-2.28.so)
        cat  3147 180457.376431:   2717 cycles:uppp:      558b70f3b0ca [unknown] (/usr/bin/cat)
        cat  3147 180457.376667:   2630 cycles:uppp:      558b70f3d86e [unknown] (/usr/bin/cat)
        cat  3147 180457.376795:   2442 cycles:uppp:      7f79362bff55 read+0x15 (/usr/lib64/libc-2.28.so)
        cat  3147 180457.376927:   2376 cycles:uppp:  ffffffff9aa00163 [unknown] ([unknown])
        cat  3147 180457.376954:   2307 cycles:uppp:      7f7936257438 _int_malloc+0x8c8 (/usr/lib64/libc-2.28.so)
        cat  3147 180457.377116:   3091 cycles:uppp:      7f7936258a70 malloc+0x0 (/usr/lib64/libc-2.28.so)
        cat  3147 180457.377362:   2945 cycles:uppp:      558b70f3a3b0 [unknown] (/usr/bin/cat)
        cat  3147 180457.377517:   2727 cycles:uppp:      558b70f3a9aa [unknown] (/usr/bin/cat)
  $

Install 'coreutils-debuginfo' to see cat's guts (symbols), but then, the
above chunk translates into this 'perf report' output:

  $ cat /tmp/report.before.3
  # To display the perf.data header info, please use --header/--header-only options.
  #
  #
  # Total Lost Samples: 0
  #
  # Samples: 13  of event 'cycles:uppp' (time slices: 180457.375844,180457.377717)
  # Event count (approx.): 33552
  #
  # Overhead  Command  Shared Object     Symbol
  # ........  .......  ................  ......................
  #
      17.69%  cat      libc-2.28.so      [.] malloc
      14.53%  cat      cat               [.] 0x000000000000586e
      13.33%  cat      libc-2.28.so      [.] _int_malloc
       8.78%  cat      cat               [.] 0x00000000000023b0
       8.71%  cat      cat               [.] 0x0000000000002554
       8.13%  cat      cat               [.] 0x00000000000029aa
       8.10%  cat      cat               [.] 0x00000000000030ca
       7.28%  cat      libc-2.28.so      [.] read
       7.08%  cat      [unknown]         [k] 0xffffffff9aa00163
       6.39%  cat      libc-2.28.so      [.] cfree@GLIBC_2.2.5

  #
  # (Tip: Order by the overhead of source file name and line number: perf report -s srcline)
  #
  $

Now lets see after applying this patch, nothing should change:

  $ perf report --time 10%/1,10%/2 > /tmp/report.after.1
  $ perf script --time 10%/1,10%/2 > /tmp/script.after.1
  $ perf report --time 0%-10%,30%-40% > /tmp/report.after.2
  $ perf script --time 0%-10%,30%-40% > /tmp/script.after.2
  $ perf report --time 180457.375844,180457.377717 > /tmp/report.after.3
  $ perf script --time 180457.375844,180457.377717 > /tmp/script.after.3
  $ diff -u /tmp/report.before.1 /tmp/report.after.1
  $ diff -u /tmp/script.before.1 /tmp/script.after.1
  $ diff -u /tmp/report.before.2 /tmp/report.after.2
  --- /tmp/report.before.2	2019-03-01 11:01:53.526094883 -0300
  +++ /tmp/report.after.2	2019-03-01 11:09:18.231770467 -0300
  @@ -352,5 +352,5 @@

   #
  -# (Tip: Generate a script for your data: perf script -g <lang>)
  +# (Tip: Treat branches as callchains: perf report --branch-history)
   #
  $ diff -u /tmp/script.before.2 /tmp/script.after.2
  $ diff -u /tmp/report.before.3 /tmp/report.after.3
  --- /tmp/report.before.3	2019-03-01 11:03:08.890045588 -0300
  +++ /tmp/report.after.3	2019-03-01 11:09:40.660224002 -0300
  @@ -22,5 +22,5 @@

   #
  -# (Tip: Order by the overhead of source file name and line number: perf report -s srcline)
  +# (Tip: List events using substring match: perf list <keyword>)
   #
  $ diff -u /tmp/script.before.3 /tmp/script.after.3
  $

Cool, just the 'perf report' tips changed, QED.

Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jin Yao <yao.jin@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1551435186-6008-1-git-send-email-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

4 files changed, 72 insertions, 62 deletions

diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index 1532ebde6c4b..ee93c18a6685 100644
--- a/tools/perf/builtin-report.c
+++ b/tools/perf/builtin-report.c
@@ -1375,36 +1375,13 @@ repeat:
         if (symbol__init(&session->header.env) < 0)
                 goto error;
 
-        report.ptime_range = perf_time__range_alloc(report.time_str,
-                                                    &report.range_size);
-        if (!report.ptime_range) {
-                ret = -ENOMEM;
-                goto error;
-        }
-
-        if (perf_time__parse_str(report.ptime_range, report.time_str) != 0) {
-                if (session->evlist->first_sample_time == 0 &&
-                    session->evlist->last_sample_time == 0) {
-                        pr_err("HINT: no first/last sample time found in perf data.\n"
-                               "Please use latest perf binary to execute 'perf record'\n"
-                               "(if '--buildid-all' is enabled, please set '--timestamp-boundary').\n");
-                        ret = -EINVAL;
-                        goto error;
-                }
-
-                report.range_num = perf_time__percent_parse_str(
-                                        report.ptime_range, report.range_size,
-                                        report.time_str,
-                                        session->evlist->first_sample_time,
-                                        session->evlist->last_sample_time);
-
-                if (report.range_num < 0) {
-                        pr_err("Invalid time string\n");
-                        ret = -EINVAL;
+        if (report.time_str) {
+                ret = perf_time__parse_for_ranges(report.time_str, session,
+                                                  &report.ptime_range,
+                                                  &report.range_size,
+                                                  &report.range_num);
+                if (ret < 0)
                         goto error;
-                }
-        } else {
-                report.range_num = 1;
         }
 
         if (session->tevent.pevent &&
@@ -1426,7 +1403,8 @@ repeat:
                 ret = 0;
 
 error:
-        zfree(&report.ptime_range);
+        if (report.ptime_range)
+                zfree(&report.ptime_range);
 
         perf_session__delete(session);
         return ret;
diff --git a/tools/perf/builtin-script.c b/tools/perf/builtin-script.c
index 2d8cb1d1682c..53f78cf3113f 100644
--- a/tools/perf/builtin-script.c
+++ b/tools/perf/builtin-script.c
@@ -3699,37 +3699,13 @@ int cmd_script(int argc, const char **argv)
         if (err < 0)
                 goto out_delete;
 
-        script.ptime_range = perf_time__range_alloc(script.time_str,
-                                                    &script.range_size);
-        if (!script.ptime_range) {
-                err = -ENOMEM;
-                goto out_delete;
-        }
-
-        /* needs to be parsed after looking up reference time */
-        if (perf_time__parse_str(script.ptime_range, script.time_str) != 0) {
-                if (session->evlist->first_sample_time == 0 &&
-                    session->evlist->last_sample_time == 0) {
-                        pr_err("HINT: no first/last sample time found in perf data.\n"
-                               "Please use latest perf binary to execute 'perf record'\n"
-                               "(if '--buildid-all' is enabled, please set '--timestamp-boundary').\n");
-                        err = -EINVAL;
-                        goto out_delete;
-                }
-
-                script.range_num = perf_time__percent_parse_str(
-                                        script.ptime_range, script.range_size,
-                                        script.time_str,
-                                        session->evlist->first_sample_time,
-                                        session->evlist->last_sample_time);
-
-                if (script.range_num < 0) {
-                        pr_err("Invalid time string\n");
-                        err = -EINVAL;
+        if (script.time_str) {
+                err = perf_time__parse_for_ranges(script.time_str, session,
+                                                  &script.ptime_range,
+                                                  &script.range_size,
+                                                  &script.range_num);
+                if (err < 0)
                         goto out_delete;
-                }
-        } else {
-                script.range_num = 1;
         }
 
         err = __cmd_script(&script);
@@ -3737,7 +3713,8 @@ int cmd_script(int argc, const char **argv)
         flush_scripting();
 
 out_delete:
-        zfree(&script.ptime_range);
+        if (script.ptime_range)
+                zfree(&script.ptime_range);
 
         perf_evlist__free_stats(session->evlist);
         perf_session__delete(session);
diff --git a/tools/perf/util/time-utils.c b/tools/perf/util/time-utils.c
index 6193b46050a5..0f53baec660e 100644
--- a/tools/perf/util/time-utils.c
+++ b/tools/perf/util/time-utils.c
@@ -11,6 +11,8 @@
 #include "perf.h"
 #include "debug.h"
 #include "time-utils.h"
+#include "session.h"
+#include "evlist.h"
 
 int parse_nsec_time(const char *str, u64 *ptime)
 {
@@ -374,7 +376,7 @@ bool perf_time__ranges_skip_sample(struct perf_time_interval *ptime_buf,
         struct perf_time_interval *ptime;
         int i;
 
-        if ((timestamp == 0) || (num == 0))
+        if ((!ptime_buf) || (timestamp == 0) || (num == 0))
                 return false;
 
         if (num == 1)
@@ -396,6 +398,53 @@ bool perf_time__ranges_skip_sample(struct perf_time_interval *ptime_buf,
         return (i == num) ? true : false;
 }
 
+int perf_time__parse_for_ranges(const char *time_str,
+                                struct perf_session *session,
+                                struct perf_time_interval **ranges,
+                                int *range_size, int *range_num)
+{
+        struct perf_time_interval *ptime_range;
+        int size, num, ret;
+
+        ptime_range = perf_time__range_alloc(time_str, &size);
+        if (!ptime_range)
+                return -ENOMEM;
+
+        if (perf_time__parse_str(ptime_range, time_str) != 0) {
+                if (session->evlist->first_sample_time == 0 &&
+                    session->evlist->last_sample_time == 0) {
+                        pr_err("HINT: no first/last sample time found in perf data.\n"
+                               "Please use latest perf binary to execute 'perf record'\n"
+                               "(if '--buildid-all' is enabled, please set '--timestamp-boundary').\n");
+                        ret = -EINVAL;
+                        goto error;
+                }
+
+                num = perf_time__percent_parse_str(
+                                ptime_range, size,
+                                time_str,
+                                session->evlist->first_sample_time,
+                                session->evlist->last_sample_time);
+
+                if (num < 0) {
+                        pr_err("Invalid time string\n");
+                        ret = -EINVAL;
+                        goto error;
+                }
+        } else {
+                num = 1;
+        }
+
+        *range_size = size;
+        *range_num = num;
+        *ranges = ptime_range;
+        return 0;
+
+error:
+        free(ptime_range);
+        return ret;
+}
+
 int timestamp__scnprintf_usec(u64 timestamp, char *buf, size_t sz)
 {
         u64  sec = timestamp / NSEC_PER_SEC;
diff --git a/tools/perf/util/time-utils.h b/tools/perf/util/time-utils.h
index 70b177d2b98c..b923de44e36f 100644
--- a/tools/perf/util/time-utils.h
+++ b/tools/perf/util/time-utils.h
@@ -23,6 +23,12 @@ bool perf_time__skip_sample(struct perf_time_interval *ptime, u64 timestamp);
 bool perf_time__ranges_skip_sample(struct perf_time_interval *ptime_buf,
                                    int num, u64 timestamp);
 
+struct perf_session;
+
+int perf_time__parse_for_ranges(const char *str, struct perf_session *session,
+                                struct perf_time_interval **ranges,
+                                int *range_size, int *range_num);
+
 int timestamp__scnprintf_usec(u64 timestamp, char *buf, size_t sz);
 
 int fetch_current_timestamp(char *buf, size_t sz);