GFS2: Ensure uptodate inode size when using O_APPEND

[safe/jmp/linux-2.6] / fs / jffs2 / background.c

diff --git a/fs/jffs2/background.c b/fs/jffs2/background.c
index 3cceef4..3ff50da 100644 (file)
--- a/fs/jffs2/background.c
+++ b/fs/jffs2/background.c
@@ -15,6 +15,7 @@
 #include <linux/completion.h>
 #include <linux/sched.h>
 #include <linux/freezer.h>
+#include <linux/kthread.h>
 #include "nodelist.h"
 
 
@@ -31,7 +32,7 @@ void jffs2_garbage_collect_trigger(struct jffs2_sb_info *c)
 /* This must only ever be called when no GC thread is currently running */
 int jffs2_start_garbage_collect_thread(struct jffs2_sb_info *c)
 {
-       pid_t pid;
+       struct task_struct *tsk;
        int ret = 0;
 
        BUG_ON(c->gc_task);
@@ -39,15 +40,16 @@ int jffs2_start_garbage_collect_thread(struct jffs2_sb_info *c)
        init_completion(&c->gc_thread_start);
        init_completion(&c->gc_thread_exit);
 
-       pid = kernel_thread(jffs2_garbage_collect_thread, c, CLONE_FS|CLONE_FILES);
-       if (pid < 0) {
-               printk(KERN_WARNING "fork failed for JFFS2 garbage collect thread: %d\n", -pid);
+       tsk = kthread_run(jffs2_garbage_collect_thread, c, "jffs2_gcd_mtd%d", c->mtd->index);
+       if (IS_ERR(tsk)) {
+               printk(KERN_WARNING "fork failed for JFFS2 garbage collect thread: %ld\n", -PTR_ERR(tsk));
                complete(&c->gc_thread_exit);
-               ret = pid;
+               ret = PTR_ERR(tsk);
        } else {
                /* Wait for it... */
-               D1(printk(KERN_DEBUG "JFFS2: Garbage collect thread is pid %d\n", pid));
+               D1(printk(KERN_DEBUG "JFFS2: Garbage collect thread is pid %d\n", tsk->pid));
                wait_for_completion(&c->gc_thread_start);
+               ret = tsk->pid;
        }
 
        return ret;
@@ -71,7 +73,6 @@ static int jffs2_garbage_collect_thread(void *_c)
 {
        struct jffs2_sb_info *c = _c;
 
-       daemonize("jffs2_gcd_mtd%d", c->mtd->index);
        allow_signal(SIGKILL);
        allow_signal(SIGSTOP);
        allow_signal(SIGCONT);
@@ -95,13 +96,22 @@ static int jffs2_garbage_collect_thread(void *_c)
                        spin_unlock(&c->erase_completion_lock);
                        
 
-               /* This thread is purely an optimisation. But if it runs when
-                  other things could be running, it actually makes things a
-                  lot worse. Use yield() and put it at the back of the runqueue
-                  every time. Especially during boot, pulling an inode in
-                  with read_inode() is much preferable to having the GC thread
-                  get there first. */
-               yield();
+               /* Problem - immediately after bootup, the GCD spends a lot
+                * of time in places like jffs2_kill_fragtree(); so much so
+                * that userspace processes (like gdm and X) are starved
+                * despite plenty of cond_resched()s and renicing.  Yield()
+                * doesn't help, either (presumably because userspace and GCD
+                * are generally competing for a higher latency resource -
+                * disk).
+                * This forces the GCD to slow the hell down.   Pulling an
+                * inode in with read_inode() is much preferable to having
+                * the GC thread get there first. */
+               schedule_timeout_interruptible(msecs_to_jiffies(50));
+
+               if (kthread_should_stop()) {
+                       D1(printk(KERN_DEBUG "jffs2_garbage_collect_thread():  kthread_stop() called.\n"));
+                       goto die;
+               }
 
                /* Put_super will send a SIGKILL and then wait on the sem.
                 */