diff options
| author | alc <alc@FreeBSD.org> | 2009-05-11 05:16:57 +0000 |
|---|---|---|
| committer | alc <alc@FreeBSD.org> | 2009-05-11 05:16:57 +0000 |
| commit | 123b385c443b5265285c082a625ac0b38d7414b9 (patch) | |
| tree | 81479028093a0118e14110db34682db9fa1420b4 /sys | |
| parent | a3bc0bfa1666e9aff669aa69c4b7e5b3bcef38d4 (diff) | |
| download | FreeBSD-src-123b385c443b5265285c082a625ac0b38d7414b9.zip FreeBSD-src-123b385c443b5265285c082a625ac0b38d7414b9.tar.gz | |
Revert CVS revision 1.94 (svn r16840). Current pmap implementations don't
suffer from the race condition that motivated revision 1.94. Consequently,
the work-around that was implemented by revision 1.94 is no longer needed.
Moreover, reverting this work-around eliminates the need for
vfs_busy_pages() to acquire the page queues lock when preparing a buffer
for read.
Reviewed by: tegge
Diffstat (limited to 'sys')
| -rw-r--r-- | sys/kern/vfs_bio.c | 12 |
1 files changed, 7 insertions, 5 deletions
diff --git a/sys/kern/vfs_bio.c b/sys/kern/vfs_bio.c index b9ae5ca..58e3491 100644 --- a/sys/kern/vfs_bio.c +++ b/sys/kern/vfs_bio.c @@ -3519,7 +3519,8 @@ retry: goto retry; } bogus = 0; - vm_page_lock_queues(); + if (clear_modify) + vm_page_lock_queues(); for (i = 0; i < bp->b_npages; i++) { m = bp->b_pages[i]; @@ -3542,17 +3543,18 @@ retry: * It may not work properly with small-block devices. * We need to find a better way. */ - pmap_remove_all(m); - if (clear_modify) + if (clear_modify) { + pmap_remove_write(m); vfs_page_set_valid(bp, foff, m); - else if (m->valid == VM_PAGE_BITS_ALL && + } else if (m->valid == VM_PAGE_BITS_ALL && (bp->b_flags & B_CACHE) == 0) { bp->b_pages[i] = bogus_page; bogus++; } foff = (foff + PAGE_SIZE) & ~(off_t)PAGE_MASK; } - vm_page_unlock_queues(); + if (clear_modify) + vm_page_unlock_queues(); VM_OBJECT_UNLOCK(obj); if (bogus) pmap_qenter(trunc_page((vm_offset_t)bp->b_data), |
