perf tools: Allow to close dso fd in case of open failure

Adding do_open function that tries to close opened
dso objects in case we fail to open the dso due to
to crossing the allowed RLIMIT_NOFILE limit.

Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jean Pihet <jean.pihet@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1401892622-30848-9-git-send-email-jolsa@kernel.org
Signed-off-by: Jiri Olsa <jolsa@kernel.org>

1 files changed, 22 insertions, 1 deletions

diff --git a/tools/perf/util/dso.c b/tools/perf/util/dso.c
index db634383156c..c30752c7eebb 100644
--- a/tools/perf/util/dso.c
+++ b/tools/perf/util/dso.c
@@ -159,6 +159,27 @@ static void dso__list_del(struct dso *dso)
         dso__data_open_cnt--;
 }
 
+static void close_first_dso(void);
+
+static int do_open(char *name)
+{
+        int fd;
+
+        do {
+                fd = open(name, O_RDONLY);
+                if (fd >= 0)
+                        return fd;
+
+                pr_debug("dso open failed, mmap: %s\n", strerror(errno));
+                if (!dso__data_open_cnt || errno != EMFILE)
+                        break;
+
+                close_first_dso();
+        } while (1);
+
+        return -1;
+}
+
 static int __open_dso(struct dso *dso, struct machine *machine)
 {
         int fd;
@@ -177,7 +198,7 @@ static int __open_dso(struct dso *dso, struct machine *machine)
                 return -EINVAL;
         }
 
-        fd = open(name, O_RDONLY);
+        fd = do_open(name);
         free(name);
         return fd;
 }