From d7e404af115bb4996afa4a0236020969ab007554 Mon Sep 17 00:00:00 2001
From: Wang Nan <wangnan0@huawei.com>
Date: Tue, 6 Sep 2016 04:58:29 +0000
Subject: [PATCH] perf record: Mark MAP_HUGETLB when synthesizing mmap events
When synthesizing mmap events, add MAP_HUGETLB map flag if the source of
mapping is file in hugetlbfs.
After this patch, perf can identify hugetlb mapping even if perf is
started after the mapping of huge pages (like with 'perf top').
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Reviewed-by: Nilay Vaish <nilayvaish@gmail.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Hou Pengyang <houpengyang@huawei.com>
Cc: Zefan Li <lizefan@huawei.com>
Link: http://lkml.kernel.org/r/1473137909-142064-4-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/util/event.c | 11 +++++++++++
1 file changed, 11 insertions(+)
diff --git a/tools/perf/util/event.c b/tools/perf/util/event.c
index 9ad7d32dba2bc..6c3017139c67d 100644
--- a/tools/perf/util/event.c
+++ b/tools/perf/util/event.c
@@ -1,5 +1,6 @@
#include <linux/types.h>
#include <sys/mman.h>
+#include <api/fs/fs.h>
#include "event.h"
#include "debug.h"
#include "hist.h"
@@ -248,6 +249,10 @@ int perf_event__synthesize_mmap_events(struct perf_tool *tool,
bool truncation = false;
unsigned long long timeout = proc_map_timeout * 1000000ULL;
int rc = 0;
+#ifdef MAP_HUGETLB
+ const char *hugetlbfs_mnt = hugetlbfs__mountpoint();
+ int hugetlbfs_mnt_len = hugetlbfs_mnt ? strlen(hugetlbfs_mnt) : 0;
+#endif
if (machine__is_default_guest(machine))
return 0;
@@ -342,6 +347,12 @@ out:
if (!strcmp(execname, ""))
strcpy(execname, anonstr);
+#ifdef MAP_HUGETLB
+ if (!strncmp(execname, hugetlbfs_mnt, hugetlbfs_mnt_len)) {
+ strcpy(execname, anonstr);
+ event->mmap2.flags |= MAP_HUGETLB;
+ }
+#endif
size = strlen(execname) + 1;
memcpy(event->mmap2.filename, execname, size);
--
2.39.5