On Thu, 03 May 2007 11:32:23 +1000 Nick Piggin <[EMAIL PROTECTED]> wrote:
> void fastcall unlock_page(struct page *page) > { > + VM_BUG_ON(!PageLocked(page)); > smp_mb__before_clear_bit(); > - if (!TestClearPageLocked(page)) > - BUG(); > - smp_mb__after_clear_bit(); > - wake_up_page(page, PG_locked); > + ClearPageLocked(page); > + if (unlikely(test_bit(PG_waiters, &page->flags))) { > + clear_bit(PG_waiters, &page->flags); > + wake_up_page(page, PG_locked); > + } > } Why is that significantly faster than plain old wake_up_page(), which tests waitqueue_active()? - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/