From mboxrd@z Thu Jan 1 00:00:00 1970 From: Li Hong Subject: Re: [PATCH 3/3] nilfs2: change sc_timer from a pointer to an embedded one in struct nilfs_sc_info Date: Sun, 11 Apr 2010 17:08:15 +0800 Message-ID: <20100411090815.GC11189@xhl> References: <20100410161543.GA9213@xhl> <20100410161700.GB9213@xhl> <20100410161752.GC9213@xhl> <20100411.114022.199103512.ryusuke@osrg.net> <20100411042931.GC10086@xhl> Mime-Version: 1.0 Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:date:from:to:subject :message-id:mail-followup-to:references:mime-version:content-type :content-disposition:in-reply-to:x-operating-system:user-agent; bh=yebKJFFJZK6i35k+IDXRpAMMi9GDSaLHvXVxNY8uAEs=; b=kG/r1knXFg0N4Z0PNa/Hzz1FGQBvYTX4TUClSaCq3mHg6gmTfvXajwKs8/3VUihj+G A/ikI+nDs0zx0B2icWXsYokw5MaHZ1KmUc3zA2uBM7Z/JkrK2bS/XO9U7UFRJJtYYx7G 9y0jguxa7DRwJpDCXBIGA5hO4+UxXHH9uyqu8= Content-Disposition: inline In-Reply-To: <20100411042931.GC10086@xhl> Sender: linux-nilfs-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Ryusuke Konishi , konishi.ryusuke-Zyj7fXuS5i5L9jVzuh4AOg@public.gmane.org, linux-nilfs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org >From 031b50dd4bc3c94687c8e587672aff2ffeefee9b Mon Sep 17 00:00:00 2001 From: Li Hong Date: Sat, 10 Apr 2010 23:25:39 +0800 Subject: [PATCH] nilfs2: change sc_timer from a pointer to an embedded one in struct nilfs_sc_info In nilfs_segctor_thread(), timer is a local variable allocated on stack. Its address can't be set to sci->sc_timer and passed in several procedures. It works now by chance, just because other procedures are called by nilfs_segctor_thread() directly or indirectly and the stack hasn't been deallocated yet. Signed-off-by: Li Hong --- fs/nilfs2/segment.c | 31 +++++++++++++------------------ fs/nilfs2/segment.h | 2 +- 2 files changed, 14 insertions(+), 19 deletions(-) diff --git a/fs/nilfs2/segment.c b/fs/nilfs2/segment.c index 514620d..b523112 100644 --- a/fs/nilfs2/segment.c +++ b/fs/nilfs2/segment.c @@ -2158,9 +2158,9 @@ static int nilfs_segctor_do_construct(struct nilfs_sc_info *sci, int mode) static void nilfs_segctor_start_timer(struct nilfs_sc_info *sci) { spin_lock(&sci->sc_state_lock); - if (sci->sc_timer && !(sci->sc_state & NILFS_SEGCTOR_COMMIT)) { - sci->sc_timer->expires = jiffies + sci->sc_interval; - add_timer(sci->sc_timer); + if (!(sci->sc_state & NILFS_SEGCTOR_COMMIT)) { + sci->sc_timer.expires = jiffies + sci->sc_interval; + add_timer(&sci->sc_timer); sci->sc_state |= NILFS_SEGCTOR_COMMIT; } spin_unlock(&sci->sc_state_lock); @@ -2365,9 +2365,7 @@ static void nilfs_segctor_accept(struct nilfs_sc_info *sci) spin_lock(&sci->sc_state_lock); sci->sc_seq_accepted = sci->sc_seq_request; spin_unlock(&sci->sc_state_lock); - - if (sci->sc_timer) - del_timer_sync(sci->sc_timer); + del_timer_sync(&sci->sc_timer); } /** @@ -2393,9 +2391,9 @@ static void nilfs_segctor_notify(struct nilfs_sc_info *sci, int mode, int err) sci->sc_flush_request &= ~FLUSH_DAT_BIT; /* re-enable timer if checkpoint creation was not done */ - if (sci->sc_timer && (sci->sc_state & NILFS_SEGCTOR_COMMIT) && - time_before(jiffies, sci->sc_timer->expires)) - add_timer(sci->sc_timer); + if ((sci->sc_state & NILFS_SEGCTOR_COMMIT) && + time_before(jiffies, sci->sc_timer.expires)) + add_timer(&sci->sc_timer); } spin_unlock(&sci->sc_state_lock); } @@ -2574,13 +2572,10 @@ static int nilfs_segctor_thread(void *arg) { struct nilfs_sc_info *sci = (struct nilfs_sc_info *)arg; struct the_nilfs *nilfs = sci->sc_sbi->s_nilfs; - struct timer_list timer; int timeout = 0; - init_timer(&timer); - timer.data = (unsigned long)current; - timer.function = nilfs_construction_timeout; - sci->sc_timer = &timer; + sci->sc_timer.data = (unsigned long)current; + sci->sc_timer.function = nilfs_construction_timeout; /* start sync. */ sci->sc_task = current; @@ -2629,7 +2624,7 @@ static int nilfs_segctor_thread(void *arg) should_sleep = 0; else if (sci->sc_state & NILFS_SEGCTOR_COMMIT) should_sleep = time_before(jiffies, - sci->sc_timer->expires); + sci->sc_timer.expires); if (should_sleep) { spin_unlock(&sci->sc_state_lock); @@ -2638,7 +2633,7 @@ static int nilfs_segctor_thread(void *arg) } finish_wait(&sci->sc_wait_daemon, &wait); timeout = ((sci->sc_state & NILFS_SEGCTOR_COMMIT) && - time_after_eq(jiffies, sci->sc_timer->expires)); + time_after_eq(jiffies, sci->sc_timer.expires)); if (nilfs_sb_dirty(nilfs) && nilfs_sb_need_update(nilfs)) set_nilfs_discontinued(nilfs); @@ -2647,8 +2642,6 @@ static int nilfs_segctor_thread(void *arg) end_thread: spin_unlock(&sci->sc_state_lock); - del_timer_sync(sci->sc_timer); - sci->sc_timer = NULL; /* end sync. */ sci->sc_task = NULL; @@ -2707,6 +2700,7 @@ static struct nilfs_sc_info *nilfs_segctor_new(struct nilfs_sb_info *sbi) INIT_LIST_HEAD(&sci->sc_write_logs); INIT_LIST_HEAD(&sci->sc_gc_inodes); INIT_LIST_HEAD(&sci->sc_copied_buffers); + init_timer(&sci->sc_timer); sci->sc_interval = HZ * NILFS_SC_DEFAULT_TIMEOUT; sci->sc_mjcp_freq = HZ * NILFS_SC_DEFAULT_SR_FREQ; @@ -2773,6 +2767,7 @@ static void nilfs_segctor_destroy(struct nilfs_sc_info *sci) down_write(&sbi->s_nilfs->ns_segctor_sem); + del_timer_sync(&sci->sc_timer); kfree(sci); } diff --git a/fs/nilfs2/segment.h b/fs/nilfs2/segment.h index 7aca765..dca1423 100644 --- a/fs/nilfs2/segment.h +++ b/fs/nilfs2/segment.h @@ -177,7 +177,7 @@ struct nilfs_sc_info { unsigned long sc_lseg_stime; /* in 1/HZ seconds */ unsigned long sc_watermark; - struct timer_list *sc_timer; + struct timer_list sc_timer; struct task_struct *sc_task; }; -- 1.6.3.3 -- To unsubscribe from this list: send the line "unsubscribe linux-nilfs" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html