perf dso: Separate generic code in dso_cache__read

Move the file specific code in the dso_cache__read function to a
separate file_read function. I'll add BPF specific code in the following
patches.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stanislav Fomichev <sdf@google.com>
Link: http://lkml.kernel.org/r/20190508132010.14512-3-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/util/dso.c b/tools/perf/util/dso.c
index cb6199c..7734f50 100644 (file)
--- a/tools/perf/util/dso.c
+++ b/tools/perf/util/dso.c
@@ -794,6 +794,31 @@ dso_cache__memcpy(struct dso_cache *cache, u64 offset,
        return cache_size;
 }
 
+static ssize_t file_read(struct dso *dso, struct machine *machine,
+                        u64 offset, char *data)
+{
+       ssize_t ret;
+
+       pthread_mutex_lock(&dso__data_open_lock);
+
+       /*
+        * dso->data.fd might be closed if other thread opened another
+        * file (dso) due to open file limit (RLIMIT_NOFILE).
+        */
+       try_to_open_dso(dso, machine);
+
+       if (dso->data.fd < 0) {
+               dso->data.status = DSO_DATA_STATUS_ERROR;
+               ret = -errno;
+               goto out;
+       }
+
+       ret = pread(dso->data.fd, data, DSO__DATA_CACHE_SIZE, offset);
+out:
+       pthread_mutex_unlock(&dso__data_open_lock);
+       return ret;
+}
+
 static ssize_t
 dso_cache__read(struct dso *dso, struct machine *machine,
                u64 offset, u8 *data, ssize_t size)
@@ -803,37 +828,18 @@ dso_cache__read(struct dso *dso, struct machine *machine,
        ssize_t ret;
 
        do {
-               u64 cache_offset;
+               u64 cache_offset = offset & DSO__DATA_CACHE_MASK;
 
                cache = zalloc(sizeof(*cache) + DSO__DATA_CACHE_SIZE);
                if (!cache)
                        return -ENOMEM;
 
-               pthread_mutex_lock(&dso__data_open_lock);
-
-               /*
-                * dso->data.fd might be closed if other thread opened another
-                * file (dso) due to open file limit (RLIMIT_NOFILE).
-                */
-               try_to_open_dso(dso, machine);
-
-               if (dso->data.fd < 0) {
-                       ret = -errno;
-                       dso->data.status = DSO_DATA_STATUS_ERROR;
-                       break;
-               }
-
-               cache_offset = offset & DSO__DATA_CACHE_MASK;
-
-               ret = pread(dso->data.fd, cache->data, DSO__DATA_CACHE_SIZE, cache_offset);
-               if (ret <= 0)
-                       break;
+               ret = file_read(dso, machine, cache_offset, cache->data);
 
                cache->offset = cache_offset;
                cache->size   = ret;
        } while (0);
 
-       pthread_mutex_unlock(&dso__data_open_lock);
 
        if (ret > 0) {
                old = dso_cache__insert(dso, cache);