Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753084Ab0ANSMP (ORCPT ); Thu, 14 Jan 2010 13:12:15 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751791Ab0ANSMO (ORCPT ); Thu, 14 Jan 2010 13:12:14 -0500 Received: from fg-out-1718.google.com ([72.14.220.154]:24895 "EHLO fg-out-1718.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751310Ab0ANSMN (ORCPT ); Thu, 14 Jan 2010 13:12:13 -0500 From: Nitin Gupta To: Hugh Dickins , Pekka Enberg Cc: Andrew Morton , Al Viro , Christoph Hellwig , Jens Axboe , Andi Kleen , linux-kernel Subject: [PATCH] [mmotm v2] comment on swap notify locking constraints Date: Thu, 14 Jan 2010 23:40:02 +0530 Message-Id: <1263492602-3052-1-git-send-email-ngupta@vflare.org> X-Mailer: git-send-email 1.6.2.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1157 Lines: 32 A block device makes swap_slot_free_notify() callback when the last reference to a swap slot is dropped. This callback is made under swap_lock and page table lock. This is a note of warning for registered callback function which must meet these constraints. Signed-off-by: Nitin Gupta --- include/linux/blkdev.h | 1 + 1 files changed, 1 insertions(+), 0 deletions(-) diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index f86df8b..fb7b3c2 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1294,6 +1294,7 @@ struct block_device_operations { unsigned long long); int (*revalidate_disk) (struct gendisk *); int (*getgeo)(struct block_device *, struct hd_geometry *); + /* this callback is with swap_lock and page table lock held */ void (*swap_slot_free_notify) (struct block_device *, unsigned long); struct module *owner; }; -- 1.6.2.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/