[JFFS2] Use yield() between GC passes in background thread.
authorDavid Woodhouse <dwmw2@infradead.org>
Thu, 8 Mar 2007 10:28:30 +0000 (10:28 +0000)
committerDavid Woodhouse <dwmw2@infradead.org>
Thu, 8 Mar 2007 10:28:30 +0000 (10:28 +0000)
commitf8a922c7bb4d93bd84b7371a8e2571e667d2afb5
tree3c412fe0a57cfd222e2a4b63f5599e5a2a08f08f
parent89e2bf61da9d7664293a57100a419f8116252607
[JFFS2] Use yield() between GC passes in background thread.

The garbage collection thread is strictly an optimisation. Everything it
does would also be done just-in-time in the context of something in
userspace trying to access the file system.

Sometimes, however, it's a pessimisation. Especially during early boot
when it's checksumming nodes and scanning inodes which are shortly going
to be pulled in by read_inode anyway. We end up building the rbtree of
node coverage twice for the same inode.

By switching to yield() instead of cond_resched() in the main loop, we
observe boot times on the OLPC system going down from about 100 seconds to
60.

Signed-off-by: David Woodhouse <dwmw2@infradead.org>
fs/jffs2/background.c