On Fri, Jan 04, 2008 at 01:35:50PM -0700, Matthew Wilcox wrote: > > > > vfs_setlease() > > > > if (f_op->setlease()) > > > > res = f_op->setlease() > > > > if (res) > > > > return res; > > > > lock_kernel() > > > > generic_setlease() > > > > unlock_kernel() > > > > Why can't the filesystem call into generic_setlease() on its own? > > Because (assuming we're rid of the BKL), fcntl_setlease() needs to > acquire the spinlock and hold it while generic_setlease() runs, so > generic_setlease() can't acquire the lock. So, the problem is that fcntl_setlease() does vfs_setlease() fasync_helper() which the bkl held over both, and you want to preserve that? But what that BKL is doing is a mystery to me--the very first thing that fasync_helper() does is kmem_cache_alloc(., GFP_KERNEL). So you won't be introducing any new problem if you lock those two operations separately. Unless I'm totally missing something. --b. - 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
