mirror of
https://github.com/torvalds/linux.git
synced 2024-12-12 06:02:38 +00:00
a5b3a80b89
Provide read-and-reset objects- and blocks-released counters for cachefilesd to use to work out whether there's anything new that can be culled. One of the problems cachefilesd has is that if all the objects in the cache are pinned by inodes lying dormant in the kernel inode cache, there isn't anything for it to cull. In such a case, it just spins around walking the filesystem tree and scanning for something to cull. This eats up a lot of CPU time. By telling cachefilesd if there have been any releases, the daemon can sleep until there is the possibility of something to do. cachefilesd finds this information by the following means: (1) When the control fd is read, the kernel presents a list of values of interest. "freleased=N" and "breleased=N" are added to this list to indicate the number of files released and number of blocks released since the last read call. At this point the counters are reset. (2) POLLIN is signalled if the number of files released becomes greater than 0. Note that by 'released' it just means that the kernel has released its interest in those files for the moment, not necessarily that the files should be deleted from the cache. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Steve Dickson <steved@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> |
||
---|---|---|
.. | ||
bind.c | ||
daemon.c | ||
interface.c | ||
internal.h | ||
Kconfig | ||
key.c | ||
main.c | ||
Makefile | ||
namei.c | ||
proc.c | ||
rdwr.c | ||
security.c | ||
xattr.c |