[PATCH 4/8] perf tools: Support multiple sort keys in a hierarchy

[Namhyung Kim <namhyung@kernel.org>]

This implements having multiple sort keys in a single hierarchy level.
Originally only single sort key is supported for each level, but now
using the ':' separator, user can set more than one sort key in a
level.

For example:

  $ perf report --hierarchy -s comm:dso,sym
  ...
  #       Overhead  Command / Shared Object / Symbol
  # ..............  ..........................................
  #
      48.67%        swapper          [kernel.vmlinux]
         34.42%        [k] intel_idle
          1.30%        [k] __tick_nohz_idle_enter
          1.03%        [k] cpuidle_reflect
       8.87%        firefox          libpthread-2.22.so
          6.60%        [.] __GI___libc_recvmsg
          1.18%        [.] pthread_cond_signal@@GLIBC_2.3.2
          1.09%        [.] 0x000000000000ff4b
       6.11%        Xorg             libc-2.22.so
          5.27%        [.] __memcpy_sse2_unaligned

In the above example, the command name and the shared object name are
shown on the same line but the symbol name is on the different line.
Since the first two are separated by ':', and the symbol is separated by
',' as usual.

Suggested-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
 tools/perf/util/sort.c | 22 ++++++++++++++++++----
 1 file changed, 18 insertions(+), 4 deletions(-)

diff --git a/tools/perf/util/sort.c b/tools/perf/util/sort.c
index 29c75f0374c4..95cee0b0d7ea 100644
--- a/tools/perf/util/sort.c
+++ b/tools/perf/util/sort.c
@@ -2307,10 +2307,22 @@ static int setup_sort_list(char *str, struct perf_evlist *evlist)
 	char *tmp, *tok;
 	int ret = 0;
 	int level = 0;
+	int next_level;
+
+	do {
+		tok = str;
+		tmp = strpbrk(str, ":, ");
+		if (tmp) {
+			if (*tmp == ':')
+				next_level = level;
+			else
+				next_level = level + 1;
+
+			*tmp = '\0';
+			str = tmp + 1;
+		}
 
-	for (tok = strtok_r(str, ", ", &tmp);
-			tok; tok = strtok_r(NULL, ", ", &tmp)) {
-		ret = sort_dimension__add(tok, evlist, level++);
+		ret = sort_dimension__add(tok, evlist, level);
 		if (ret == -EINVAL) {
 			error("Invalid --sort key: `%s'", tok);
 			break;
@@ -2318,7 +2330,9 @@ static int setup_sort_list(char *str, struct perf_evlist *evlist)
 			error("Unknown --sort key: `%s'", tok);
 			break;
 		}
-	}
+
+		level = next_level;
+	} while (tmp);
 
 	return ret;
 }
-- 
2.7.1