On Sat, Sep 18, 2010 at 03:09:31PM +0200, Arnd Bergmann wrote: > This prepares the removal of the big kernel lock from the > file locking code. We still use the BKL as long as fs/lockd > uses it and ceph might sleep, but we can flip the definition > to a private spinlock as soon as that's done. > All users outside of fs/lockd get converted to use > lock_flocks() instead of lock_kernel() where appropriate. > > Based on an earlier patch to use a spinlock from Matthew > Wilcox, who has attempted this a few times before. An even > earlier attempt to use a semaphore instead of the BKL > apparently was made by Andrew Morton about ten years ago, > but reverted for performance reasons. Actually, I attempted the semaphore conversion ten years ago, but Andrew Morton reverted it due to the performance regression. I believe it was Apache, when it was using file locks to synchronise between threads. Patch looks good; Acked-by: Matthew Wilcox <willy@xxxxxxxxxxxxxxx> -- Matthew Wilcox Intel Open Source Technology Centre "Bill, look, we understand that you're interested in selling us this operating system, but compare it to ours. We can't possibly take such a retrograde step." -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
