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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| .. | ||
| Kconfig | ||
| Makefile | ||
| alloc.c | ||
| alloc.h | ||
| bmap.c | ||
| bmap.h | ||
| btnode.c | ||
| btnode.h | ||
| btree.c | ||
| btree.h | ||
| cpfile.c | ||
| cpfile.h | ||
| dat.c | ||
| dat.h | ||
| dir.c | ||
| direct.c | ||
| direct.h | ||
| export.h | ||
| file.c | ||
| gcinode.c | ||
| ifile.c | ||
| ifile.h | ||
| inode.c | ||
| ioctl.c | ||
| mdt.c | ||
| mdt.h | ||
| namei.c | ||
| nilfs.h | ||
| page.c | ||
| page.h | ||
| recovery.c | ||
| sb.h | ||
| segbuf.c | ||
| segbuf.h | ||
| segment.c | ||
| segment.h | ||
| sufile.c | ||
| sufile.h | ||
| super.c | ||
| the_nilfs.c | ||
| the_nilfs.h | ||