From fb045adb99d9b7c562dc7fef834857f78249daa1 Mon Sep 17 00:00:00 2001 From: Nick Piggin Date: Fri, 7 Jan 2011 17:49:55 +1100 Subject: fs: dcache reduce branches in lookup path Reduce some branches and memory accesses in dcache lookup by adding dentry flags to indicate common d_ops are set, rather than having to check them. This saves a pointer memory access (dentry->d_op) in common path lookup situations, and saves another pointer load and branch in cases where we have d_op but not the particular operation. Patched with: git grep -E '[.>]([[:space:]])*d_op([[:space:]])*=' | xargs sed -e 's/\([^\t ]*\)->d_op = \(.*\);/d_set_d_op(\1, \2);/' -e 's/\([^\t ]*\)\.d_op = \(.*\);/d_set_d_op(\&\1, \2);/' -i Signed-off-by: Nick Piggin --- fs/fat/inode.c | 4 ++-- fs/fat/namei_msdos.c | 6 +++--- fs/fat/namei_vfat.c | 8 ++++---- 3 files changed, 9 insertions(+), 9 deletions(-) (limited to 'fs/fat') diff --git a/fs/fat/inode.c b/fs/fat/inode.c index 8cccfebee180..206351af7c58 100644 --- a/fs/fat/inode.c +++ b/fs/fat/inode.c @@ -750,7 +750,7 @@ static struct dentry *fat_fh_to_dentry(struct super_block *sb, */ result = d_obtain_alias(inode); if (!IS_ERR(result)) - result->d_op = sb->s_root->d_op; + d_set_d_op(result, sb->s_root->d_op); return result; } @@ -800,7 +800,7 @@ static struct dentry *fat_get_parent(struct dentry *child) parent = d_obtain_alias(inode); if (!IS_ERR(parent)) - parent->d_op = sb->s_root->d_op; + d_set_d_op(parent, sb->s_root->d_op); out: unlock_super(sb); diff --git a/fs/fat/namei_msdos.c b/fs/fat/namei_msdos.c index 3b3e072d8982..35ffe43afa4b 100644 --- a/fs/fat/namei_msdos.c +++ b/fs/fat/namei_msdos.c @@ -227,10 +227,10 @@ static struct dentry *msdos_lookup(struct inode *dir, struct dentry *dentry, } out: unlock_super(sb); - dentry->d_op = &msdos_dentry_operations; + d_set_d_op(dentry, &msdos_dentry_operations); dentry = d_splice_alias(inode, dentry); if (dentry) - dentry->d_op = &msdos_dentry_operations; + d_set_d_op(dentry, &msdos_dentry_operations); return dentry; error: @@ -673,7 +673,7 @@ static int msdos_fill_super(struct super_block *sb, void *data, int silent) } sb->s_flags |= MS_NOATIME; - sb->s_root->d_op = &msdos_dentry_operations; + d_set_d_op(sb->s_root, &msdos_dentry_operations); unlock_super(sb); return 0; } diff --git a/fs/fat/namei_vfat.c b/fs/fat/namei_vfat.c index 4fc06278db48..3be5ed7d859f 100644 --- a/fs/fat/namei_vfat.c +++ b/fs/fat/namei_vfat.c @@ -766,11 +766,11 @@ static struct dentry *vfat_lookup(struct inode *dir, struct dentry *dentry, out: unlock_super(sb); - dentry->d_op = sb->s_root->d_op; + d_set_d_op(dentry, sb->s_root->d_op); dentry->d_time = dentry->d_parent->d_inode->i_version; dentry = d_splice_alias(inode, dentry); if (dentry) { - dentry->d_op = sb->s_root->d_op; + d_set_d_op(dentry, sb->s_root->d_op); dentry->d_time = dentry->d_parent->d_inode->i_version; } return dentry; @@ -1072,9 +1072,9 @@ static int vfat_fill_super(struct super_block *sb, void *data, int silent) } if (MSDOS_SB(sb)->options.name_check != 's') - sb->s_root->d_op = &vfat_ci_dentry_ops; + d_set_d_op(sb->s_root, &vfat_ci_dentry_ops); else - sb->s_root->d_op = &vfat_dentry_ops; + d_set_d_op(sb->s_root, &vfat_dentry_ops); unlock_super(sb); return 0; -- cgit v1.2.3