From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756596AbZCVTai (ORCPT ); Sun, 22 Mar 2009 15:30:38 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755010AbZCVT0p (ORCPT ); Sun, 22 Mar 2009 15:26:45 -0400 Received: from brick.kernel.dk ([93.163.65.50]:52611 "EHLO kernel.dk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755368AbZCVT0L (ORCPT ); Sun, 22 Mar 2009 15:26:11 -0400 From: Jens Axboe To: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org Cc: chris.mason@oracle.com, david@fromorbit.com, npiggin@suse.de, hch@infradead.org, akpm@linux-foundation.org, Jens Axboe Subject: [PATCH 09/12] writeback: include default_backing_dev_info in writeback Date: Sun, 22 Mar 2009 20:26:01 +0100 Message-Id: <1237749964-8343-10-git-send-email-jens.axboe@oracle.com> X-Mailer: git-send-email 1.6.2.12.g83676 In-Reply-To: <1237749964-8343-1-git-send-email-jens.axboe@oracle.com> References: <1237749964-8343-1-git-send-email-jens.axboe@oracle.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org We see dirty inodes there occasionally, so better be safe and write them out. Signed-off-by: Jens Axboe --- fs/fs-writeback.c | 60 +++++++++++++++++++++++++------------------ include/linux/backing-dev.h | 5 +++ include/linux/writeback.h | 1 + mm/backing-dev.c | 35 +++++++++++++++---------- 4 files changed, 62 insertions(+), 39 deletions(-) diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c index 741e127..5fcdcd4 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -34,6 +34,10 @@ */ int nr_pdflush_threads = 0; +static void generic_sync_wb_inodes(struct bdi_writeback *wb, + struct super_block *sb, + struct writeback_control *wbc); + /** * writeback_acquire - attempt to get exclusive writeback access to a device * @bdi: the device's backing_dev_info structure @@ -149,7 +153,7 @@ int bdi_start_writeback(struct backing_dev_info *bdi, struct super_block *sb, * older_than_this takes precedence over nr_to_write. So we'll only write back * all dirty pages if they are all attached to "old" mappings. */ -static void wb_kupdated(struct bdi_writeback *wb) +void wb_kupdated(struct bdi_writeback *wb) { long nr_to_write; struct writeback_control wbc = { @@ -177,11 +181,7 @@ static void wb_kupdated(struct bdi_writeback *wb) } } -static void generic_sync_wb_inodes(struct bdi_writeback *wb, - struct super_block *sb, - struct writeback_control *wbc); - -static void wb_writeback(struct bdi_writeback *wb) +void wb_writeback(struct bdi_writeback *wb) { struct writeback_control wbc = { .bdi = wb->bdi, @@ -217,6 +217,34 @@ static void wb_writeback(struct bdi_writeback *wb) } /* + * This will be inlined in bdi_writeback_task() once we get rid of any + * dirty inodes on the default_backing_dev_info + */ +void wb_do_writeback(struct bdi_writeback *wb) +{ + /* + * We get here in two cases: + * + * schedule_timeout() returned because the dirty writeback + * interval has elapsed. If that happens, we will be able + * to acquire the writeback lock and will proceed to do + * kupdated style writeout. + * + * Someone called bdi_start_writeback(), which will acquire + * the writeback lock. This means our writeback_acquire() + * below will fail and we call into bdi_pdflush() for + * pdflush style writeout. + * + */ + if (writeback_acquire(wb)) + wb_kupdated(wb); + else + wb_writeback(wb); + + writeback_release(wb); +} + +/* * Handle writeback of dirty data for the device backed by this bdi. Also * wakes up periodically and does kupdated style flushing. */ @@ -229,26 +257,8 @@ int bdi_writeback_task(struct bdi_writeback *wb) schedule_timeout(dirty_writeback_interval); try_to_freeze(); - /* - * We get here in two cases: - * - * schedule_timeout() returned because the dirty writeback - * interval has elapsed. If that happens, we will be able - * to acquire the writeback lock and will proceed to do - * kupdated style writeout. - * - * Someone called bdi_start_writeback(), which will acquire - * the writeback lock. This means our writeback_acquire() - * below will fail and we call into bdi_pdflush() for - * pdflush style writeout. - * - */ - if (writeback_acquire(wb)) - wb_kupdated(wb); - else - wb_writeback(wb); + wb_do_writeback(wb); - writeback_release(wb); finish_wait(&wb->wait, &wait); } diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h index 279bc3f..9dd8cb9 100644 --- a/include/linux/backing-dev.h +++ b/include/linux/backing-dev.h @@ -308,6 +308,11 @@ static inline bool bdi_cap_swap_backed(struct backing_dev_info *bdi) return bdi->capabilities & BDI_CAP_SWAP_BACKED; } +static inline bool bdi_cap_flush_forker(struct backing_dev_info *bdi) +{ + return bdi->capabilities & BDI_CAP_FLUSH_FORKER; +} + static inline bool mapping_cap_writeback_dirty(struct address_space *mapping) { return bdi_cap_writeback_dirty(mapping->backing_dev_info); diff --git a/include/linux/writeback.h b/include/linux/writeback.h index f96fea3..5f1d59f 100644 --- a/include/linux/writeback.h +++ b/include/linux/writeback.h @@ -69,6 +69,7 @@ void writeback_inodes(struct writeback_control *wbc); int inode_wait(void *); void sync_inodes_sb(struct super_block *, int wait); void sync_inodes(int wait); +void wb_do_writeback(struct bdi_writeback *wb); /* writeback.h requires fs.h; it, too, is not included from here. */ static inline void wait_on_inode(struct inode *inode) diff --git a/mm/backing-dev.c b/mm/backing-dev.c index 21406f2..7551648 100644 --- a/mm/backing-dev.c +++ b/mm/backing-dev.c @@ -357,14 +357,6 @@ static int bdi_forker_task(void *ptr) struct bdi_writeback *wb; DEFINE_WAIT(wait); - /* - * Should never trigger on the default bdi - */ - if (wb_has_dirty_io(me)) { - bdi_flush_io(me->bdi); - WARN_ON(1); - } - prepare_to_wait(&me->wait, &wait, TASK_INTERRUPTIBLE); smp_mb(); @@ -372,6 +364,21 @@ static int bdi_forker_task(void *ptr) schedule(); finish_wait(&me->wait, &wait); + + /* + * Ideally we'd like not to see any dirty inodes on the + * default_backing_dev_info. Until these are tracked down, + * perform the same writeback here that bdi_writeback_task + * does. For logic, see comment in + * fs/fs-writeback.c:bdi_writeback_task() + */ + if (wb_has_dirty_io(me)) + wb_do_writeback(me); + + /* + * This is our real job - check for pending entries in + * bdi_pending_list, and create the tasks that got added + */ repeat: bdi = NULL; spin_lock_bh(&bdi_lock); @@ -489,7 +496,7 @@ int bdi_register(struct backing_dev_info *bdi, struct device *parent, * and add other bdi's to the list. They will get a thread created * on-demand when they need it. */ - if (bdi->capabilities & BDI_CAP_FLUSH_FORKER) { + if (bdi_cap_flush_forker(bdi)) { struct bdi_writeback *wb; wb = bdi_new_wb(bdi); @@ -505,12 +512,12 @@ int bdi_register(struct backing_dev_info *bdi, struct device *parent, ret = -ENOMEM; goto exit; } - } else { - spin_lock_bh(&bdi_lock); - list_add_tail_rcu(&bdi->bdi_list, &bdi_list); - spin_unlock_bh(&bdi_lock); } + spin_lock_bh(&bdi_lock); + list_add_tail_rcu(&bdi->bdi_list, &bdi_list); + spin_unlock_bh(&bdi_lock); + bdi->dev = dev; bdi_debug_register(bdi, dev_name(dev)); @@ -570,7 +577,7 @@ static void bdi_wb_shutdown(struct backing_dev_info *bdi) void bdi_unregister(struct backing_dev_info *bdi) { if (bdi->dev) { - if (!(bdi->capabilities & BDI_CAP_FLUSH_FORKER)) + if (!bdi_cap_flush_forker(bdi)) bdi_wb_shutdown(bdi); bdi_debug_unregister(bdi); device_unregister(bdi->dev); -- 1.6.2.12.g83676