From: Nathan Scott Date: Wed, 2 Nov 2005 00:43:58 +0000 (+1100) Subject: [XFS] Improve buffered read throughput by removing unnecessary timer calls X-Git-Tag: v2.6.15-rc1~450^2~2^2~39 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=4aeb664c2561c0bae18d7a3a141d7d2acf126da1;p=linux-2.6 [XFS] Improve buffered read throughput by removing unnecessary timer calls that showed in ´kernel profiles. SGI-PV: 925163 SGI-Modid: xfs-linux:xfs-kern:23861a Signed-off-by: Nathan Scott --- diff --git a/fs/xfs/linux-2.6/xfs_iops.c b/fs/xfs/linux-2.6/xfs_iops.c index 77708a8c9f..68c83ec311 100644 --- a/fs/xfs/linux-2.6/xfs_iops.c +++ b/fs/xfs/linux-2.6/xfs_iops.c @@ -69,6 +69,137 @@ #include #include +/* + * Change the requested timestamp in the given inode. + * We don't lock across timestamp updates, and we don't log them but + * we do record the fact that there is dirty information in core. + * + * NOTE -- callers MUST combine XFS_ICHGTIME_MOD or XFS_ICHGTIME_CHG + * with XFS_ICHGTIME_ACC to be sure that access time + * update will take. Calling first with XFS_ICHGTIME_ACC + * and then XFS_ICHGTIME_MOD may fail to modify the access + * timestamp if the filesystem is mounted noacctm. + */ +void +xfs_ichgtime( + xfs_inode_t *ip, + int flags) +{ + struct inode *inode = LINVFS_GET_IP(XFS_ITOV(ip)); + timespec_t tv; + + /* + * We're not supposed to change timestamps in readonly-mounted + * filesystems. Throw it away if anyone asks us. + */ + if (unlikely(IS_RDONLY(inode))) + return; + + /* + * Don't update access timestamps on reads if mounted "noatime". + * Throw it away if anyone asks us. + */ + if (unlikely( + (ip->i_mount->m_flags & XFS_MOUNT_NOATIME || IS_NOATIME(inode)) && + (flags & (XFS_ICHGTIME_ACC|XFS_ICHGTIME_MOD|XFS_ICHGTIME_CHG)) == + XFS_ICHGTIME_ACC)) + return; + + nanotime(&tv); + if (flags & XFS_ICHGTIME_MOD) { + inode->i_mtime = tv; + ip->i_d.di_mtime.t_sec = (__int32_t)tv.tv_sec; + ip->i_d.di_mtime.t_nsec = (__int32_t)tv.tv_nsec; + } + if (flags & XFS_ICHGTIME_ACC) { + inode->i_atime = tv; + ip->i_d.di_atime.t_sec = (__int32_t)tv.tv_sec; + ip->i_d.di_atime.t_nsec = (__int32_t)tv.tv_nsec; + } + if (flags & XFS_ICHGTIME_CHG) { + inode->i_ctime = tv; + ip->i_d.di_ctime.t_sec = (__int32_t)tv.tv_sec; + ip->i_d.di_ctime.t_nsec = (__int32_t)tv.tv_nsec; + } + + /* + * We update the i_update_core field _after_ changing + * the timestamps in order to coordinate properly with + * xfs_iflush() so that we don't lose timestamp updates. + * This keeps us from having to hold the inode lock + * while doing this. We use the SYNCHRONIZE macro to + * ensure that the compiler does not reorder the update + * of i_update_core above the timestamp updates above. + */ + SYNCHRONIZE(); + ip->i_update_core = 1; + if (!(inode->i_state & I_LOCK)) + mark_inode_dirty_sync(inode); +} + +/* + * Variant on the above which avoids querying the system clock + * in situations where we know the Linux inode timestamps have + * just been updated (and so we can update our inode cheaply). + * We also skip the readonly and noatime checks here, they are + * also catered for already. + */ +void +xfs_ichgtime_fast( + xfs_inode_t *ip, + struct inode *inode, + int flags) +{ + timespec_t *tvp; + + /* + * We're not supposed to change timestamps in readonly-mounted + * filesystems. Throw it away if anyone asks us. + */ + if (unlikely(IS_RDONLY(inode))) + return; + + /* + * Don't update access timestamps on reads if mounted "noatime". + * Throw it away if anyone asks us. + */ + if (unlikely( + (ip->i_mount->m_flags & XFS_MOUNT_NOATIME || IS_NOATIME(inode)) && + ((flags & (XFS_ICHGTIME_ACC|XFS_ICHGTIME_MOD|XFS_ICHGTIME_CHG)) == + XFS_ICHGTIME_ACC))) + return; + + if (flags & XFS_ICHGTIME_MOD) { + tvp = &inode->i_mtime; + ip->i_d.di_mtime.t_sec = (__int32_t)tvp->tv_sec; + ip->i_d.di_mtime.t_nsec = (__int32_t)tvp->tv_nsec; + } + if (flags & XFS_ICHGTIME_ACC) { + tvp = &inode->i_atime; + ip->i_d.di_atime.t_sec = (__int32_t)tvp->tv_sec; + ip->i_d.di_atime.t_nsec = (__int32_t)tvp->tv_nsec; + } + if (flags & XFS_ICHGTIME_CHG) { + tvp = &inode->i_ctime; + ip->i_d.di_ctime.t_sec = (__int32_t)tvp->tv_sec; + ip->i_d.di_ctime.t_nsec = (__int32_t)tvp->tv_nsec; + } + + /* + * We update the i_update_core field _after_ changing + * the timestamps in order to coordinate properly with + * xfs_iflush() so that we don't lose timestamp updates. + * This keeps us from having to hold the inode lock + * while doing this. We use the SYNCHRONIZE macro to + * ensure that the compiler does not reorder the update + * of i_update_core above the timestamp updates above. + */ + SYNCHRONIZE(); + ip->i_update_core = 1; + if (!(inode->i_state & I_LOCK)) + mark_inode_dirty_sync(inode); +} + /* * Pull the link count and size up from the xfs inode to the linux inode diff --git a/fs/xfs/linux-2.6/xfs_iops.h b/fs/xfs/linux-2.6/xfs_iops.h index 6a69a62c36..415de44b6a 100644 --- a/fs/xfs/linux-2.6/xfs_iops.h +++ b/fs/xfs/linux-2.6/xfs_iops.h @@ -48,4 +48,8 @@ extern void linvfs_unwritten_done(struct buffer_head *, int); extern int xfs_ioctl(struct bhv_desc *, struct inode *, struct file *, int, unsigned int, void __user *); +struct xfs_inode; +extern void xfs_ichgtime(struct xfs_inode *, int); +extern void xfs_ichgtime_fast(struct xfs_inode *, struct inode *, int); + #endif /* __XFS_IOPS_H__ */ diff --git a/fs/xfs/linux-2.6/xfs_lrw.c b/fs/xfs/linux-2.6/xfs_lrw.c index 3b5fabe8da..c04f0c063c 100644 --- a/fs/xfs/linux-2.6/xfs_lrw.c +++ b/fs/xfs/linux-2.6/xfs_lrw.c @@ -302,7 +302,7 @@ xfs_read( xfs_iunlock(ip, XFS_IOLOCK_SHARED); if (likely(!(ioflags & IO_INVIS))) - xfs_ichgtime(ip, XFS_ICHGTIME_ACC); + xfs_ichgtime_fast(ip, inode, XFS_ICHGTIME_ACC); unlock_isem: if (unlikely(ioflags & IO_ISDIRECT)) @@ -367,7 +367,7 @@ xfs_sendfile( XFS_STATS_ADD(xs_read_bytes, ret); if (likely(!(ioflags & IO_INVIS))) - xfs_ichgtime(ip, XFS_ICHGTIME_ACC); + xfs_ichgtime_fast(ip, LINVFS_GET_IP(vp), XFS_ICHGTIME_ACC); return ret; } @@ -732,15 +732,10 @@ start: } } - /* - * On Linux, generic_file_write updates the times even if - * no data is copied in so long as the write had a size. - * - * We must update xfs' times since revalidate will overcopy xfs. - */ - if (!(ioflags & IO_INVIS)) { - xfs_ichgtime(xip, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG); + if (likely(!(ioflags & IO_INVIS))) { inode_update_time(inode, 1); + xfs_ichgtime_fast(xip, inode, + XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG); } /* diff --git a/fs/xfs/linux-2.6/xfs_vnode.h b/fs/xfs/linux-2.6/xfs_vnode.h index 76a8dddb43..ef1c65f42f 100644 --- a/fs/xfs/linux-2.6/xfs_vnode.h +++ b/fs/xfs/linux-2.6/xfs_vnode.h @@ -566,13 +566,6 @@ static __inline__ void vn_flagclr(struct vnode *vp, uint flag) spin_unlock(&vp->v_lock); } -/* - * Update modify/access/change times on the vnode - */ -#define VN_MTIMESET(vp, tvp) (LINVFS_GET_IP(vp)->i_mtime = *(tvp)) -#define VN_ATIMESET(vp, tvp) (LINVFS_GET_IP(vp)->i_atime = *(tvp)) -#define VN_CTIMESET(vp, tvp) (LINVFS_GET_IP(vp)->i_ctime = *(tvp)) - /* * Dealing with bad inodes */ diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c index 5bf7b709f9..a648cc8ce9 100644 --- a/fs/xfs/xfs_inode.c +++ b/fs/xfs/xfs_inode.c @@ -3688,73 +3688,6 @@ xfs_iroundup( return( 0 ); } -/* - * Change the requested timestamp in the given inode. - * We don't lock across timestamp updates, and we don't log them but - * we do record the fact that there is dirty information in core. - * - * NOTE -- callers MUST combine XFS_ICHGTIME_MOD or XFS_ICHGTIME_CHG - * with XFS_ICHGTIME_ACC to be sure that access time - * update will take. Calling first with XFS_ICHGTIME_ACC - * and then XFS_ICHGTIME_MOD may fail to modify the access - * timestamp if the filesystem is mounted noacctm. - */ -void -xfs_ichgtime(xfs_inode_t *ip, - int flags) -{ - timespec_t tv; - vnode_t *vp = XFS_ITOV(ip); - struct inode *inode = LINVFS_GET_IP(vp); - - /* - * We're not supposed to change timestamps in readonly-mounted - * filesystems. Throw it away if anyone asks us. - */ - if (unlikely(vp->v_vfsp->vfs_flag & VFS_RDONLY)) - return; - - /* - * Don't update access timestamps on reads if mounted "noatime" - * Throw it away if anyone asks us. - */ - if ((ip->i_mount->m_flags & XFS_MOUNT_NOATIME || IS_NOATIME(inode)) && - ((flags & (XFS_ICHGTIME_ACC|XFS_ICHGTIME_MOD|XFS_ICHGTIME_CHG)) - == XFS_ICHGTIME_ACC)) - return; - - nanotime(&tv); - if (flags & XFS_ICHGTIME_MOD) { - VN_MTIMESET(vp, &tv); - ip->i_d.di_mtime.t_sec = (__int32_t)tv.tv_sec; - ip->i_d.di_mtime.t_nsec = (__int32_t)tv.tv_nsec; - } - if (flags & XFS_ICHGTIME_ACC) { - VN_ATIMESET(vp, &tv); - ip->i_d.di_atime.t_sec = (__int32_t)tv.tv_sec; - ip->i_d.di_atime.t_nsec = (__int32_t)tv.tv_nsec; - } - if (flags & XFS_ICHGTIME_CHG) { - VN_CTIMESET(vp, &tv); - ip->i_d.di_ctime.t_sec = (__int32_t)tv.tv_sec; - ip->i_d.di_ctime.t_nsec = (__int32_t)tv.tv_nsec; - } - - /* - * We update the i_update_core field _after_ changing - * the timestamps in order to coordinate properly with - * xfs_iflush() so that we don't lose timestamp updates. - * This keeps us from having to hold the inode lock - * while doing this. We use the SYNCHRONIZE macro to - * ensure that the compiler does not reorder the update - * of i_update_core above the timestamp updates above. - */ - SYNCHRONIZE(); - ip->i_update_core = 1; - if (!(inode->i_state & I_LOCK)) - mark_inode_dirty_sync(inode); -} - #ifdef XFS_ILOCK_TRACE ktrace_t *xfs_ilock_trace_buf;