f2fs: name gc task as per the block device

Currently GC task is started for each f2fs formatted/mounted device.
But, when we check the task list, using 'ps', there is no distinguishing
factor between the tasks. So, name the task as per the block device just
like the flusher threads.
Also, remove the macro GC_THREAD_NAME and instead use the name: f2fs_gc
to avoid name length truncation, as the command length is 16
-> TASK_COMM_LEN 16 and example name like:
f2fs_gc_task:8:16 -> this exceeds name length

Before Patch for 2 F2FS formatted partitions:
root  28061  0.0  0.0  0 0 ? S 10:31   0:00 [f2fs_gc_task]
root  28087  0.0  0.0  0 0 ? S 10:32   0:00 [f2fs_gc_task]

After Patch:
root  16756  0.0  0.0  0  0 ?  S  14:57   0:00 [f2fs_gc-8:18]
root  16765  0.0  0.0  0  0 ?  S  14:57   0:00 [f2fs_gc-8:19]

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>

diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
index 8d293cb685ba1caec0d3e98af15af4242c3ef2cb..b1e498503e59defca3f974db8d973e5fce868cb9 100644 (file)
--- a/fs/f2fs/gc.c
+++ b/fs/f2fs/gc.c
@@ -90,6 +90,7 @@ static int gc_thread_func(void *data)
 int start_gc_thread(struct f2fs_sb_info *sbi)
 {
        struct f2fs_gc_kthread *gc_th;
+       dev_t dev = sbi->sb->s_bdev->bd_dev;
 
        if (!test_opt(sbi, BG_GC))
                return 0;
@@ -100,7 +101,7 @@ int start_gc_thread(struct f2fs_sb_info *sbi)
        sbi->gc_thread = gc_th;
        init_waitqueue_head(&sbi->gc_thread->gc_wait_queue_head);
        sbi->gc_thread->f2fs_gc_task = kthread_run(gc_thread_func, sbi,
-                               GC_THREAD_NAME);
+                       "f2fs_gc-%u:%u", MAJOR(dev), MINOR(dev));
        if (IS_ERR(gc_th->f2fs_gc_task)) {
                kfree(gc_th);
                return -ENOMEM;

diff --git a/fs/f2fs/gc.h b/fs/f2fs/gc.h
index b026d9354ccddf97bc8f82efbddd47bea8e2743f..3abdf83b5c16742f56ed20ecfe4d92f8d9259d2f 100644 (file)
--- a/fs/f2fs/gc.h
+++ b/fs/f2fs/gc.h
@@ -8,7 +8,6 @@
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
  */
-#define GC_THREAD_NAME "f2fs_gc_task"
 #define GC_THREAD_MIN_WB_PAGES         1       /*
                                                 * a threshold to determine
                                                 * whether IO subsystem is idle