Commit 4aeb664c authored by Nathan Scott's avatar Nathan Scott

[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: default avatarNathan Scott <nathans@sgi.com>
parent 0fdfb375
......@@ -69,6 +69,137 @@
#include <linux/xattr.h>
#include <linux/namei.h>
/*
* 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
......
......@@ -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__ */
......@@ -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 @@ xfs_write(
}
}
/*
* 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);
}
/*
......
......@@ -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
*/
......
......@@ -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;
......
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