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fa0d7e3de6
RCU free the struct inode. This will allow: - Subsequent store-free path walking patch. The inode must be consulted for permissions when walking, so an RCU inode reference is a must. - sb_inode_list_lock to be moved inside i_lock because sb list walkers who want to take i_lock no longer need to take sb_inode_list_lock to walk the list in the first place. This will simplify and optimize locking. - Could remove some nested trylock loops in dcache code - Could potentially simplify things a bit in VM land. Do not need to take the page lock to follow page->mapping. The downsides of this is the performance cost of using RCU. In a simple creat/unlink microbenchmark, performance drops by about 10% due to inability to reuse cache-hot slab objects. As iterations increase and RCU freeing starts kicking over, this increases to about 20%. In cases where inode lifetimes are longer (ie. many inodes may be allocated during the average life span of a single inode), a lot of this cache reuse is not applicable, so the regression caused by this patch is smaller. The cache-hot regression could largely be avoided by using SLAB_DESTROY_BY_RCU, however this adds some complexity to list walking and store-free path walking, so I prefer to implement this at a later date, if it is shown to be a win in real situations. I haven't found a regression in any non-micro benchmark so I doubt it will be a problem. Signed-off-by: Nick Piggin <npiggin@kernel.dk> |
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.. | ||
acl.c | ||
acl.h | ||
aops.c | ||
bmap.c | ||
bmap.h | ||
dentry.c | ||
dir.c | ||
dir.h | ||
export.c | ||
file.c | ||
gfs2.h | ||
glock.c | ||
glock.h | ||
glops.c | ||
glops.h | ||
incore.h | ||
inode.c | ||
inode.h | ||
Kconfig | ||
lock_dlm.c | ||
log.c | ||
log.h | ||
lops.c | ||
lops.h | ||
main.c | ||
Makefile | ||
meta_io.c | ||
meta_io.h | ||
ops_fstype.c | ||
ops_inode.c | ||
quota.c | ||
quota.h | ||
recovery.c | ||
recovery.h | ||
rgrp.c | ||
rgrp.h | ||
super.c | ||
super.h | ||
sys.c | ||
sys.h | ||
trace_gfs2.h | ||
trans.c | ||
trans.h | ||
util.c | ||
util.h | ||
xattr.c | ||
xattr.h |