perf tools: Introduce perf_session class

That does all the initialization boilerplate, opening the file,
reading the header, checking if it is valid, etc.

And that will as well have the threads list, kmap (now) global
variable, etc, so that we can handle two (or more) perf.data files
describing sessions to compare.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1260573842-19720-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 10 insertions, 3 deletions

diff --git a/tools/perf/builtin-kmem.c b/tools/perf/builtin-kmem.c
index fe73435..2071d24 100644
--- a/tools/perf/builtin-kmem.c
+++ b/tools/perf/builtin-kmem.c
@@ -6,6 +6,7 @@
 #include "util/symbol.h"
 #include "util/thread.h"
 #include "util/header.h"
+#include "util/session.h"
 
 #include "util/parse-options.h"
 #include "util/trace-event.h"
@@ -20,7 +21,6 @@ typedef int (*sort_fn_t)(struct alloc_stat *, struct alloc_stat *);
 
 static char const		*input_name = "perf.data";
 
-static struct perf_header	*header;
 static u64			sample_type;
 
 static int			alloc_flag;
@@ -367,11 +367,18 @@ static struct perf_file_handler file_handler = {
 
 static int read_events(void)
 {
+	int err;
+	struct perf_session *session = perf_session__new(input_name, O_RDONLY, 0);
+
+	if (session == NULL)
+		return -ENOMEM;
+
 	register_idle_thread();
 	register_perf_file_handler(&file_handler);
 
-	return mmap_dispatch_perf_file(&header, input_name, 0, 0,
-				       &event__cwdlen, &event__cwd);
+	err = perf_session__process_events(session, 0, &event__cwdlen, &event__cwd);
+	perf_session__delete(session);
+	return err;
 }
 
 static double fragmentation(unsigned long n_req, unsigned long n_alloc)