From mboxrd@z Thu Jan 1 00:00:00 1970 From: Glauber Costa Subject: [PATCH 3/4] dcache set size Date: Fri, 29 Jul 2011 17:44:18 +0400 Message-ID: <1311947059-17209-4-git-send-email-glommer@parallels.com> References: <1311947059-17209-1-git-send-email-glommer@parallels.com> Cc: linux-fsdevel@vger.kernel.org, containers@lists.linux-foundation.org, Pavel Emelyanov , Al Viro , Hugh Dickins , Nick Piggin , Andrea Arcangeli , Rik van Riel , Dave Hansen , James Bottomley , David Chinner , Glauber Costa To: linux-kernel@vger.kernel.org Return-path: In-Reply-To: <1311947059-17209-1-git-send-email-glommer@parallels.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org Simple patch that provides a function allowing its caller to set the maximum number of dentries that can exist at the same time at a given super block. Will be used in a later patch. Signed-off-by: Glauber Costa CC: Dave Chinner --- fs/dcache.c | 12 ++++++++++++ include/linux/dcache.h | 1 + 2 files changed, 13 insertions(+), 0 deletions(-) diff --git a/fs/dcache.c b/fs/dcache.c index 3bdb106..4369aa2 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -1202,6 +1202,18 @@ static int dcache_mem_check(struct super_block *sb) return -ENOMEM; } +int vfs_set_dcache_size(struct super_block *sb, int size) +{ + unsigned long dr = percpu_counter_sum_positive(&sb->s_nr_dentry); + + if (size != sb->s_nr_dentry_max) + prune_dcache_sb(sb, dr - size); + + sb->s_nr_dentry_max = size; + + return 0; +} + /** * __d_alloc - allocate a dcache entry * @sb: filesystem it will belong to diff --git a/include/linux/dcache.h b/include/linux/dcache.h index d37d2a7..cd1ab71 100644 --- a/include/linux/dcache.h +++ b/include/linux/dcache.h @@ -251,6 +251,7 @@ extern int d_invalidate(struct dentry *); /* only used at mount-time */ extern struct dentry * d_alloc_root(struct inode *); +extern int vfs_set_dcache_size(struct super_block *sb, int size); /* - the ramfs-type tree */ extern void d_genocide(struct dentry *); -- 1.7.6