Vlad Apostolov wrote:
Eric Sandeen wrote:
Defining XFS_DM_EVENT* macros to 0 in the absence of
CONFIG_XFS_DMAPI allows gcc to optimize away tests that
should never be true. Also wrap one hunk of xfs_unmount
in #ifdef CONFIG_XFS_DMAPI
Good idea Eric. A few remarks and a question below.
+#ifdef CONFIG_XFS_DMAPI
CONFIG_XFS_DMAPI is only defined when the DMAPI is statically linked
to the kernel. When DMAPI is configured as a module,
CONFIG_XFS_DMAPI_MODULE
is defined. The HAVE_DMAPI is defined for both, static and module DMAPI
configurations.
Hmm... ok. kernel.org doesn't have that so you'll need to take care moving this
patch to the kernel.org tree I guess.
/* Defines for determining if an event message should be sent. */
#define DM_EVENT_ENABLED(vfsp, ip, event) ( \
unlikely ((vfsp)->vfs_flag & VFS_DMI) && \
@@ -78,6 +79,11 @@ typedef enum {
( ((io)->io_dmevmask & (1 << event)) || \
((io)->io_mount->m_dmevmask & (1 << event)) ) \
)
+#else
+#define DM_EVENT_ENABLED(vfsp, ip, event) (0)
The above should use the new two arguments DM_EVENT_ENABLED macro.
+#define DM_EVENT_ENABLED_IO(vfsp, io, event) (0)
What is this DM_EVENT_ENABLE_IO macro for?
Ah, this is just the differernce between kernel.org & CVS I guess.
I'm just re-defining existing macros in 2.6.22.1 to no-ops.
DM_EVENT_ENABLE_IO must have been removed from CVS w/o removing from
kernel.org (yet) - and I guess same goes for the argument count.
Anyway here's a CVS patch, sorry:
------
Defining XFS_DM_EVENT* macros to 0 in the absence of
CONFIG_XFS_DMAPI allows gcc to optimize away tests that
should never be true. Also wrap one hunk of xfs_unmount
in #ifdef CONFIG_XFS_DMAPI
Stack deltas on x86, gcc 4.1:
xfs_create -16
xfs_free_file_space -4
xfs_getbmap +4
xfs_link -8
xfs_mkidr -20
xfs_read -24
xfs_remove -12
xfs_rename -8
xfs_rmdir -16
xfs_setattr -20
xfs_splice_read -20
xfs_splice_write -20
xfs_unmount -48
xfs_write -20
Signed-off-by: Eric Sandeen <sandeen@xxxxxxxxxxx>
Index: linux.orig/fs/xfs/xfs_dmapi.h
===================================================================
--- linux.orig/fs/xfs/xfs_dmapi.h
+++ linux/fs/xfs/xfs_dmapi.h
@@ -67,11 +67,15 @@ typedef enum {
#define HAVE_DM_RIGHT_T
/* Defines for determining if an event message should be sent. */
+#ifdef HAVE_DMAPI
#define DM_EVENT_ENABLED(ip, event) ( \
unlikely (XFS_MTOVFS((ip)->i_mount)->vfs_flag & VFS_DMI) && \
( ((ip)->i_d.di_dmevmask & (1 << event)) || \
((ip)->i_mount->m_dmevmask & (1 << event)) ) \
)
+#else
+#define DM_EVENT_ENABLED(ip, event) (0)
+#endif
#define DM_XFS_VALID_FS_EVENTS ( \
(1 << DM_EVENT_PREUNMOUNT) | \
Index: linux.orig/fs/xfs/xfs_vfsops.c
===================================================================
--- linux.orig/fs/xfs/xfs_vfsops.c
+++ linux/fs/xfs/xfs_vfsops.c
@@ -572,6 +572,7 @@ xfs_unmount(
rip = mp->m_rootip;
rvp = XFS_ITOV(rip);
+#ifdef HAVE_DMAPI
if (vfsp->vfs_flag & VFS_DMI) {
error = XFS_SEND_PREUNMOUNT(mp, vfsp,
rvp, DM_RIGHT_NULL, rvp, DM_RIGHT_NULL,
@@ -584,7 +585,7 @@ xfs_unmount(
unmount_event_flags = (mp->m_dmevmask & (1<<DM_EVENT_UNMOUNT))?
0 : DM_FLAGS_UNWANTED;
}
-
+#endif
/*
* First blow any referenced inode from this file system
* out of the reference cache, and delete the timer.