Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932823Ab1BYVjZ (ORCPT ); Fri, 25 Feb 2011 16:39:25 -0500 Received: from smtp-out.google.com ([216.239.44.51]:54697 "EHLO smtp-out.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932661Ab1BYVjU (ORCPT ); Fri, 25 Feb 2011 16:39:20 -0500 DomainKey-Signature: a=rsa-sha1; s=beta; d=google.com; c=nofws; q=dns; h=from:to:cc:subject:date:message-id:x-mailer:in-reply-to:references; b=A82jdvUy2tqIVfkEpJJcBd6M6F/j/aVy5QmBMl6bd8upSklA47REYmPXKVlWS5dIv fk0kXnXxUBlx29XzUX0kQ== From: Greg Thelen To: Andrew Morton Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, containers@lists.osdl.org, Andrea Righi , Balbir Singh , KAMEZAWA Hiroyuki , Daisuke Nishimura , Minchan Kim , Ciju Rajan K , David Rientjes , Wu Fengguang , Chad Talbott , Justin TerAvest , Vivek Goyal , Greg Thelen Subject: [PATCH v5 4/9] writeback: create dirty_info structure Date: Fri, 25 Feb 2011 13:35:55 -0800 Message-Id: <1298669760-26344-5-git-send-email-gthelen@google.com> X-Mailer: git-send-email 1.7.3.1 In-Reply-To: <1298669760-26344-1-git-send-email-gthelen@google.com> References: <1298669760-26344-1-git-send-email-gthelen@google.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 9802 Lines: 285 Bundle dirty limits and dirty memory usage metrics into a dirty_info structure to simplify interfaces of routines that need all. Signed-off-by: Greg Thelen Acked-by: KAMEZAWA Hiroyuki --- Changelog since v4: - Within new dirty_info structure, replaced nr_reclaimable with nr_file_dirty and nr_unstable_nfs to give callers finer grain dirty usage information. - Added new dirty_info_reclaimable() function. - Made more use of dirty_info structure in throttle_vm_writeout(). Changelog since v3: - This is a new patch in v4. fs/fs-writeback.c | 7 ++--- include/linux/writeback.h | 15 ++++++++++++- mm/backing-dev.c | 18 +++++++++------ mm/page-writeback.c | 50 ++++++++++++++++++++++---------------------- mm/vmstat.c | 6 +++- 5 files changed, 57 insertions(+), 39 deletions(-) diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c index 59c6e49..d75e4da 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -595,12 +595,11 @@ static void __writeback_inodes_sb(struct super_block *sb, static inline bool over_bground_thresh(void) { - unsigned long background_thresh, dirty_thresh; + struct dirty_info info; - global_dirty_limits(&background_thresh, &dirty_thresh); + global_dirty_info(&info); - return (global_page_state(NR_FILE_DIRTY) + - global_page_state(NR_UNSTABLE_NFS) > background_thresh); + return dirty_info_reclaimable(&info) > info.background_thresh; } /* diff --git a/include/linux/writeback.h b/include/linux/writeback.h index 0ead399..a06fb38 100644 --- a/include/linux/writeback.h +++ b/include/linux/writeback.h @@ -84,6 +84,19 @@ static inline void inode_sync_wait(struct inode *inode) /* * mm/page-writeback.c */ +struct dirty_info { + unsigned long dirty_thresh; + unsigned long background_thresh; + unsigned long nr_file_dirty; + unsigned long nr_writeback; + unsigned long nr_unstable_nfs; +}; + +static inline unsigned long dirty_info_reclaimable(struct dirty_info *info) +{ + return info->nr_file_dirty + info->nr_unstable_nfs; +} + #ifdef CONFIG_BLOCK void laptop_io_completion(struct backing_dev_info *info); void laptop_sync_completion(void); @@ -124,7 +137,7 @@ struct ctl_table; int dirty_writeback_centisecs_handler(struct ctl_table *, int, void __user *, size_t *, loff_t *); -void global_dirty_limits(unsigned long *pbackground, unsigned long *pdirty); +void global_dirty_info(struct dirty_info *info); unsigned long bdi_dirty_limit(struct backing_dev_info *bdi, unsigned long dirty); diff --git a/mm/backing-dev.c b/mm/backing-dev.c index 027100d..17a06ab 100644 --- a/mm/backing-dev.c +++ b/mm/backing-dev.c @@ -66,8 +66,7 @@ static int bdi_debug_stats_show(struct seq_file *m, void *v) { struct backing_dev_info *bdi = m->private; struct bdi_writeback *wb = &bdi->wb; - unsigned long background_thresh; - unsigned long dirty_thresh; + struct dirty_info dirty_info; unsigned long bdi_thresh; unsigned long nr_dirty, nr_io, nr_more_io, nr_wb; struct inode *inode; @@ -82,8 +81,8 @@ static int bdi_debug_stats_show(struct seq_file *m, void *v) nr_more_io++; spin_unlock(&inode_lock); - global_dirty_limits(&background_thresh, &dirty_thresh); - bdi_thresh = bdi_dirty_limit(bdi, dirty_thresh); + global_dirty_info(&dirty_info); + bdi_thresh = bdi_dirty_limit(bdi, dirty_info.dirty_thresh); #define K(x) ((x) << (PAGE_SHIFT - 10)) seq_printf(m, @@ -99,9 +98,14 @@ static int bdi_debug_stats_show(struct seq_file *m, void *v) "state: %8lx\n", (unsigned long) K(bdi_stat(bdi, BDI_WRITEBACK)), (unsigned long) K(bdi_stat(bdi, BDI_RECLAIMABLE)), - K(bdi_thresh), K(dirty_thresh), - K(background_thresh), nr_dirty, nr_io, nr_more_io, - !list_empty(&bdi->bdi_list), bdi->state); + K(bdi_thresh), + K(dirty_info.dirty_thresh), + K(dirty_info.background_thresh), + nr_dirty, + nr_io, + nr_more_io, + !list_empty(&bdi->bdi_list), + bdi->state); #undef K return 0; diff --git a/mm/page-writeback.c b/mm/page-writeback.c index 4408e54..00424b9 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -398,7 +398,7 @@ unsigned long determine_dirtyable_memory(void) } /* - * global_dirty_limits - background-writeback and dirty-throttling thresholds + * global_dirty_info - return dirty thresholds and usage metrics * * Calculate the dirty thresholds based on sysctl parameters * - vm.dirty_background_ratio or vm.dirty_background_bytes @@ -406,7 +406,7 @@ unsigned long determine_dirtyable_memory(void) * The dirty limits will be lifted by 1/4 for PF_LESS_THROTTLE (ie. nfsd) and * real-time tasks. */ -void global_dirty_limits(unsigned long *pbackground, unsigned long *pdirty) +void global_dirty_info(struct dirty_info *info) { unsigned long background; unsigned long dirty; @@ -426,6 +426,10 @@ void global_dirty_limits(unsigned long *pbackground, unsigned long *pdirty) else background = (dirty_background_ratio * available_memory) / 100; + info->nr_file_dirty = global_page_state(NR_FILE_DIRTY); + info->nr_writeback = global_page_state(NR_WRITEBACK); + info->nr_unstable_nfs = global_page_state(NR_UNSTABLE_NFS); + if (background >= dirty) background = dirty / 2; tsk = current; @@ -433,8 +437,8 @@ void global_dirty_limits(unsigned long *pbackground, unsigned long *pdirty) background += background / 4; dirty += dirty / 4; } - *pbackground = background; - *pdirty = dirty; + info->background_thresh = background; + info->dirty_thresh = dirty; } /* @@ -478,12 +482,9 @@ unsigned long bdi_dirty_limit(struct backing_dev_info *bdi, unsigned long dirty) static void balance_dirty_pages(struct address_space *mapping, unsigned long write_chunk) { - unsigned long nr_reclaimable; + struct dirty_info sys_info; long bdi_nr_reclaimable; - unsigned long nr_writeback; long bdi_nr_writeback; - unsigned long background_thresh; - unsigned long dirty_thresh; unsigned long bdi_thresh; unsigned long pages_written = 0; unsigned long pause = 1; @@ -498,22 +499,19 @@ static void balance_dirty_pages(struct address_space *mapping, .range_cyclic = 1, }; - nr_reclaimable = global_page_state(NR_FILE_DIRTY) + - global_page_state(NR_UNSTABLE_NFS); - nr_writeback = global_page_state(NR_WRITEBACK); - - global_dirty_limits(&background_thresh, &dirty_thresh); + global_dirty_info(&sys_info); /* * Throttle it only when the background writeback cannot * catch-up. This avoids (excessively) small writeouts * when the bdi limits are ramping up. */ - if (nr_reclaimable + nr_writeback <= - (background_thresh + dirty_thresh) / 2) + if (dirty_info_reclaimable(&sys_info) + sys_info.nr_writeback <= + (sys_info.background_thresh + + sys_info.dirty_thresh) / 2) break; - bdi_thresh = bdi_dirty_limit(bdi, dirty_thresh); + bdi_thresh = bdi_dirty_limit(bdi, sys_info.dirty_thresh); bdi_thresh = task_dirty_limit(current, bdi_thresh); /* @@ -542,7 +540,8 @@ static void balance_dirty_pages(struct address_space *mapping, */ dirty_exceeded = (bdi_nr_reclaimable + bdi_nr_writeback > bdi_thresh) - || (nr_reclaimable + nr_writeback > dirty_thresh); + || (dirty_info_reclaimable(&sys_info) + + sys_info.nr_writeback > sys_info.dirty_thresh); if (!dirty_exceeded) break; @@ -595,7 +594,8 @@ static void balance_dirty_pages(struct address_space *mapping, * background_thresh, to keep the amount of dirty memory low. */ if ((laptop_mode && pages_written) || - (!laptop_mode && (nr_reclaimable > background_thresh))) + (!laptop_mode && (dirty_info_reclaimable(&sys_info) > + sys_info.background_thresh))) bdi_start_background_writeback(bdi); } @@ -655,21 +655,21 @@ EXPORT_SYMBOL(balance_dirty_pages_ratelimited_nr); void throttle_vm_writeout(gfp_t gfp_mask) { - unsigned long background_thresh; - unsigned long dirty_thresh; + struct dirty_info sys_info; for ( ; ; ) { - global_dirty_limits(&background_thresh, &dirty_thresh); + global_dirty_info(&sys_info); /* * Boost the allowable dirty threshold a bit for page * allocators so they don't get DoS'ed by heavy writers */ - dirty_thresh += dirty_thresh / 10; /* wheeee... */ + sys_info.dirty_thresh += + sys_info.dirty_thresh / 10; /* wheeee... */ - if (global_page_state(NR_UNSTABLE_NFS) + - global_page_state(NR_WRITEBACK) <= dirty_thresh) - break; + if (sys_info.nr_unstable_nfs + + sys_info.nr_writeback <= sys_info.dirty_thresh) + break; congestion_wait(BLK_RW_ASYNC, HZ/10); /* diff --git a/mm/vmstat.c b/mm/vmstat.c index 0c3b504..ec95924 100644 --- a/mm/vmstat.c +++ b/mm/vmstat.c @@ -1044,6 +1044,7 @@ static void *vmstat_start(struct seq_file *m, loff_t *pos) { unsigned long *v; int i, stat_items_size; + struct dirty_info dirty_info; if (*pos >= ARRAY_SIZE(vmstat_text)) return NULL; @@ -1062,8 +1063,9 @@ static void *vmstat_start(struct seq_file *m, loff_t *pos) v[i] = global_page_state(i); v += NR_VM_ZONE_STAT_ITEMS; - global_dirty_limits(v + NR_DIRTY_BG_THRESHOLD, - v + NR_DIRTY_THRESHOLD); + global_dirty_info(&dirty_info); + v[NR_DIRTY_BG_THRESHOLD] = dirty_info.background_thresh; + v[NR_DIRTY_THRESHOLD] = dirty_info.dirty_thresh; v += NR_VM_WRITEBACK_STAT_ITEMS; #ifdef CONFIG_VM_EVENT_COUNTERS -- 1.7.3.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/