Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752935AbbGAB0R (ORCPT ); Tue, 30 Jun 2015 21:26:17 -0400 Received: from mail.kernel.org ([198.145.29.136]:58525 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752500AbbGABZx (ORCPT ); Tue, 30 Jun 2015 21:25:53 -0400 From: Jaegeuk Kim To: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net Cc: Jaegeuk Kim Subject: [PATCH 1/2] f2fs: check the largest extent at look-up time Date: Tue, 30 Jun 2015 18:25:45 -0700 Message-Id: <1435713946-6910-1-git-send-email-jaegeuk@kernel.org> X-Mailer: git-send-email 2.1.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2901 Lines: 97 Because of the extent shrinker or other -ENOMEM scenarios, it cannot guarantee that the largest extent would be cached in the tree all the time. Instead of relying on extent_tree, we can simply check the cached one in extent tree accordingly. Signed-off-by: Jaegeuk Kim --- fs/f2fs/data.c | 16 ++++++++++++++-- include/trace/events/f2fs.h | 12 ++++++------ 2 files changed, 20 insertions(+), 8 deletions(-) diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index b6c28bb..8f059e0 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -511,12 +511,22 @@ static bool f2fs_lookup_extent_tree(struct inode *inode, pgoff_t pgofs, struct f2fs_sb_info *sbi = F2FS_I_SB(inode); struct extent_tree *et = F2FS_I(inode)->extent_tree; struct extent_node *en; + bool ret = false; f2fs_bug_on(sbi, !et); trace_f2fs_lookup_extent_tree_start(inode, pgofs); read_lock(&et->lock); + + if (et->largest.fofs <= pgofs && + et->largest.fofs + et->largest.len > pgofs) { + *ei = et->largest; + ret = true; + stat_inc_read_hit(sbi->sb); + goto out; + } + en = __lookup_extent_tree(et, pgofs); if (en) { *ei = en->ei; @@ -525,13 +535,15 @@ static bool f2fs_lookup_extent_tree(struct inode *inode, pgoff_t pgofs, list_move_tail(&en->list, &sbi->extent_list); et->cached_en = en; spin_unlock(&sbi->extent_lock); + ret = true; stat_inc_read_hit(sbi->sb); } +out: stat_inc_total_hit(sbi->sb); read_unlock(&et->lock); - trace_f2fs_lookup_extent_tree_end(inode, pgofs, en); - return en ? true : false; + trace_f2fs_lookup_extent_tree_end(inode, pgofs, ei); + return ret; } /* return true, if on-disk extent should be updated */ diff --git a/include/trace/events/f2fs.h b/include/trace/events/f2fs.h index 04856a2..a019465 100644 --- a/include/trace/events/f2fs.h +++ b/include/trace/events/f2fs.h @@ -1099,11 +1099,11 @@ TRACE_EVENT(f2fs_lookup_extent_tree_start, TRACE_EVENT_CONDITION(f2fs_lookup_extent_tree_end, TP_PROTO(struct inode *inode, unsigned int pgofs, - struct extent_node *en), + struct extent_info *ei), - TP_ARGS(inode, pgofs, en), + TP_ARGS(inode, pgofs, ei), - TP_CONDITION(en), + TP_CONDITION(ei), TP_STRUCT__entry( __field(dev_t, dev) @@ -1118,9 +1118,9 @@ TRACE_EVENT_CONDITION(f2fs_lookup_extent_tree_end, __entry->dev = inode->i_sb->s_dev; __entry->ino = inode->i_ino; __entry->pgofs = pgofs; - __entry->fofs = en->ei.fofs; - __entry->blk = en->ei.blk; - __entry->len = en->ei.len; + __entry->fofs = ei->fofs; + __entry->blk = ei->blk; + __entry->len = ei->len; ), TP_printk("dev = (%d,%d), ino = %lu, pgofs = %u, " -- 2.1.1 -- 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/