mirror of https://gitee.com/openkylin/linux.git
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 | ||
| acl.c | ||
| endian24.h | ||
| file.c | ||
| inode.c | ||
| ioctl.c | ||
| jfs_acl.h | ||
| jfs_btree.h | ||
| jfs_debug.c | ||
| jfs_debug.h | ||
| jfs_dinode.h | ||
| jfs_dmap.c | ||
| jfs_dmap.h | ||
| jfs_dtree.c | ||
| jfs_dtree.h | ||
| jfs_extent.c | ||
| jfs_extent.h | ||
| jfs_filsys.h | ||
| jfs_imap.c | ||
| jfs_imap.h | ||
| jfs_incore.h | ||
| jfs_inode.c | ||
| jfs_inode.h | ||
| jfs_lock.h | ||
| jfs_logmgr.c | ||
| jfs_logmgr.h | ||
| jfs_metapage.c | ||
| jfs_metapage.h | ||
| jfs_mount.c | ||
| jfs_superblock.h | ||
| jfs_txnmgr.c | ||
| jfs_txnmgr.h | ||
| jfs_types.h | ||
| jfs_umount.c | ||
| jfs_unicode.c | ||
| jfs_unicode.h | ||
| jfs_uniupr.c | ||
| jfs_xattr.h | ||
| jfs_xtree.c | ||
| jfs_xtree.h | ||
| namei.c | ||
| resize.c | ||
| super.c | ||
| symlink.c | ||
| xattr.c | ||