perf callchain: Make callchain cursors TLS

perf top -G has a race on callchain cursor between main thread and
display thread. Since the callchain cursors are used locally make them
thread-local data would solve the problem.

Signed-off-by: Namhyung Kim <namhyung.kim@lge.com>
Reported-by: Sunjin Yang <fan4326@gmail.com>
Suggested-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Sunjin Yang <fan4326@gmail.com>
Link: http://lkml.kernel.org/r/1338443007-24857-1-git-send-email-namhyung.kim@lge.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index 4820614..3b6f8e4 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -288,7 +288,8 @@
 	return bi;
 }
 
-int machine__resolve_callchain(struct machine *self, struct perf_evsel *evsel,
+int machine__resolve_callchain(struct machine *self,
+			       struct perf_evsel *evsel __used,
 			       struct thread *thread,
 			       struct ip_callchain *chain,
 			       struct symbol **parent)
@@ -297,7 +298,7 @@
 	unsigned int i;
 	int err;
 
-	callchain_cursor_reset(&evsel->hists.callchain_cursor);
+	callchain_cursor_reset(&callchain_cursor);
 
 	for (i = 0; i < chain->nr; i++) {
 		u64 ip;
@@ -333,7 +334,7 @@
 				break;
 		}
 
-		err = callchain_cursor_append(&evsel->hists.callchain_cursor,
+		err = callchain_cursor_append(&callchain_cursor,
 					      ip, al.map, al.sym);
 		if (err)
 			return err;
@@ -1428,7 +1429,6 @@
 			  int print_sym, int print_dso, int print_symoffset)
 {
 	struct addr_location al;
-	struct callchain_cursor *cursor = &evsel->hists.callchain_cursor;
 	struct callchain_cursor_node *node;
 
 	if (perf_event__preprocess_sample(event, machine, &al, sample,
@@ -1446,10 +1446,10 @@
 				error("Failed to resolve callchain. Skipping\n");
 			return;
 		}
-		callchain_cursor_commit(cursor);
+		callchain_cursor_commit(&callchain_cursor);
 
 		while (1) {
-			node = callchain_cursor_current(cursor);
+			node = callchain_cursor_current(&callchain_cursor);
 			if (!node)
 				break;
 
@@ -1465,7 +1465,7 @@
 			}
 			printf("\n");
 
-			callchain_cursor_advance(cursor);
+			callchain_cursor_advance(&callchain_cursor);
 		}
 
 	} else {