[XFS] Switch kernel thread handling to the kthread_ API

SGI-PV: 942063
SGI-Modid: xfs-linux:xfs-kern:198388a

Signed-off-by: Christoph Hellwig <hch@sgi.com>
Signed-off-by: Nathan Scott <nathans@sgi.com>

4 files changed, 17 insertions, 46 deletions

diff --git a/fs/xfs/linux-2.6/xfs_buf.c b/fs/xfs/linux-2.6/xfs_buf.c
index e6340906342c..655bf4a78afe 100644
--- a/fs/xfs/linux-2.6/xfs_buf.c
+++ b/fs/xfs/linux-2.6/xfs_buf.c
@@ -54,6 +54,7 @@
 #include <linux/percpu.h>
 #include <linux/blkdev.h>
 #include <linux/hash.h>
+#include <linux/kthread.h>
 
 #include "xfs_linux.h"
 
@@ -1742,9 +1743,7 @@ pagebuf_runall_queues(
 }
 
 /* Defines for pagebuf daemon */
-STATIC DECLARE_COMPLETION(xfsbufd_done);
 STATIC struct task_struct *xfsbufd_task;
-STATIC int xfsbufd_active;
 STATIC int xfsbufd_force_flush;
 STATIC int xfsbufd_force_sleep;
 
@@ -1770,14 +1769,8 @@ xfsbufd(
         xfs_buftarg_t           *target;
         xfs_buf_t               *pb, *n;
 
-        /*  Set up the thread  */
-        daemonize("xfsbufd");
         current->flags |= PF_MEMALLOC;
 
-        xfsbufd_task = current;
-        xfsbufd_active = 1;
-        barrier();
-
         INIT_LIST_HEAD(&tmp);
         do {
                 if (unlikely(freezing(current))) {
@@ -1825,9 +1818,9 @@ xfsbufd(
                         purge_addresses();
 
                 xfsbufd_force_flush = 0;
-        } while (xfsbufd_active);
+        } while (!kthread_should_stop());
 
-        complete_and_exit(&xfsbufd_done, 0);
+        return 0;
 }
 
 /*
@@ -1910,9 +1903,11 @@ xfs_buf_daemons_start(void)
         if (!xfsdatad_workqueue)
                 goto out_destroy_xfslogd_workqueue;
 
-        error = kernel_thread(xfsbufd, NULL, CLONE_FS|CLONE_FILES);
-        if (error < 0)
+        xfsbufd_task = kthread_run(xfsbufd, NULL, "xfsbufd");
+        if (IS_ERR(xfsbufd_task)) {
+                error = PTR_ERR(xfsbufd_task);
                 goto out_destroy_xfsdatad_workqueue;
+        }
         return 0;
 
  out_destroy_xfsdatad_workqueue:
@@ -1929,10 +1924,7 @@ xfs_buf_daemons_start(void)
 STATIC void
 xfs_buf_daemons_stop(void)
 {
-        xfsbufd_active = 0;
-        barrier();
-        wait_for_completion(&xfsbufd_done);
-
+        kthread_stop(xfsbufd_task);
         destroy_workqueue(xfslogd_workqueue);
         destroy_workqueue(xfsdatad_workqueue);
 }
diff --git a/fs/xfs/linux-2.6/xfs_super.c b/fs/xfs/linux-2.6/xfs_super.c
index 910e43bfc95b..0da87bfc9999 100644
--- a/fs/xfs/linux-2.6/xfs_super.c
+++ b/fs/xfs/linux-2.6/xfs_super.c
@@ -72,6 +72,7 @@
 #include <linux/mount.h>
 #include <linux/mempool.h>
 #include <linux/writeback.h>
+#include <linux/kthread.h>
 
 STATIC struct quotactl_ops linvfs_qops;
 STATIC struct super_operations linvfs_sops;
@@ -516,25 +517,16 @@ xfssyncd(
 {
         long                    timeleft;
         vfs_t                   *vfsp = (vfs_t *) arg;
-        struct list_head        tmp;
         struct vfs_sync_work    *work, *n;
+        LIST_HEAD               (tmp);
 
-        daemonize("xfssyncd");
-
-        vfsp->vfs_sync_work.w_vfs = vfsp;
-        vfsp->vfs_sync_work.w_syncer = vfs_sync_worker;
-        vfsp->vfs_sync_task = current;
-        wmb();
-        wake_up(&vfsp->vfs_wait_sync_task);
-
-        INIT_LIST_HEAD(&tmp);
         timeleft = (xfs_syncd_centisecs * HZ) / 100;
         for (;;) {
                 set_current_state(TASK_INTERRUPTIBLE);
                 timeleft = schedule_timeout(timeleft);
                 /* swsusp */
                 try_to_freeze();
-                if (vfsp->vfs_flag & VFS_UMOUNT)
+                if (kthread_should_stop())
                         break;
 
                 spin_lock(&vfsp->vfs_sync_lock);
@@ -563,10 +555,6 @@ xfssyncd(
                 }
         }
 
-        vfsp->vfs_sync_task = NULL;
-        wmb();
-        wake_up(&vfsp->vfs_wait_sync_task);
-
         return 0;
 }
 
@@ -574,13 +562,11 @@ STATIC int
 linvfs_start_syncd(
         vfs_t                   *vfsp)
 {
-        int                     pid;
-
-        pid = kernel_thread(xfssyncd, (void *) vfsp,
-                        CLONE_VM | CLONE_FS | CLONE_FILES);
-        if (pid < 0)
-                return -pid;
-        wait_event(vfsp->vfs_wait_sync_task, vfsp->vfs_sync_task);
+        vfsp->vfs_sync_work.w_syncer = vfs_sync_worker;
+        vfsp->vfs_sync_work.w_vfs = vfsp;
+        vfsp->vfs_sync_task = kthread_run(xfssyncd, vfsp, "xfssyncd");
+        if (IS_ERR(vfsp->vfs_sync_task))
+                return -PTR_ERR(vfsp->vfs_sync_task);
         return 0;
 }
 
@@ -588,11 +574,7 @@ STATIC void
 linvfs_stop_syncd(
         vfs_t                   *vfsp)
 {
-        vfsp->vfs_flag |= VFS_UMOUNT;
-        wmb();
-
-        wake_up_process(vfsp->vfs_sync_task);
-        wait_event(vfsp->vfs_wait_sync_task, !vfsp->vfs_sync_task);
+        kthread_stop(vfsp->vfs_sync_task);
 }
 
 STATIC void
diff --git a/fs/xfs/linux-2.6/xfs_vfs.c b/fs/xfs/linux-2.6/xfs_vfs.c
index 669c61644959..34cc902ec119 100644
--- a/fs/xfs/linux-2.6/xfs_vfs.c
+++ b/fs/xfs/linux-2.6/xfs_vfs.c
@@ -251,7 +251,6 @@ vfs_allocate( void )
         bhv_head_init(VFS_BHVHEAD(vfsp), "vfs");
         INIT_LIST_HEAD(&vfsp->vfs_sync_list);
         spin_lock_init(&vfsp->vfs_sync_lock);
-        init_waitqueue_head(&vfsp->vfs_wait_sync_task);
         init_waitqueue_head(&vfsp->vfs_wait_single_sync_task);
         return vfsp;
 }
diff --git a/fs/xfs/linux-2.6/xfs_vfs.h b/fs/xfs/linux-2.6/xfs_vfs.h
index 7ee1f714e9ba..f0ab574fb47a 100644
--- a/fs/xfs/linux-2.6/xfs_vfs.h
+++ b/fs/xfs/linux-2.6/xfs_vfs.h
@@ -65,7 +65,6 @@ typedef struct vfs {
         spinlock_t              vfs_sync_lock;  /* work item list lock */
         int                     vfs_sync_seq;   /* sync thread generation no. */
         wait_queue_head_t       vfs_wait_single_sync_task;
-        wait_queue_head_t       vfs_wait_sync_task;
 } vfs_t;
 
 #define vfs_fbhv                vfs_bh.bh_first /* 1st on vfs behavior chain */
@@ -96,7 +95,6 @@ typedef enum {
 #define VFS_RDONLY              0x0001  /* read-only vfs */
 #define VFS_GRPID               0x0002  /* group-ID assigned from directory */
 #define VFS_DMI                 0x0004  /* filesystem has the DMI enabled */
-#define VFS_UMOUNT              0x0008  /* unmount in progress */
 #define VFS_END                 0x0008  /* max flag */
 
 #define SYNC_ATTR               0x0001  /* sync attributes */