From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Sun, 7 Jan 2001 12:49:21 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Sun, 7 Jan 2001 12:49:12 -0500 Received: from mail.asahi-net.or.jp ([202.224.39.39]:62530 "HELO mail.asahi-net.or.jp") by vger.kernel.org with SMTP id ; Sun, 7 Jan 2001 12:48:59 -0500 Date: Mon, 08 Jan 2001 02:46:51 +0900 Message-ID: <87ae93l0fo.wl@strawberry.hibi-local.net> From: HIBINO Kei To: linux-kernel@vger.kernel.org, alan@lxorguk.ukuu.org.uk Subject: [PATCH] Atomic lock User-Agent: Wanderlust/2.5.4 (Smooth) SEMI/1.14.3 (Ushinoya) FLIM/1.14.2 (Yagi-Nishiguchi) APEL/10.3 Emacs/20.7 (i386-debian-linux-gnu) MULE/4.1 (AOI) MIME-Version: 1.0 (generated by SEMI 1.14.3 - "Ushinoya") Content-Type: text/plain; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org I think atomic lock is needed for SMP code. diff -ur linux-2.2.19pre6/drivers/block/ll_rw_blk.c linux-2.2.19pre6+lockfix/drivers/block/ll_rw_blk.c --- linux-2.2.19pre6/drivers/block/ll_rw_blk.c Mon Dec 11 09:49:41 2000 +++ linux-2.2.19pre6+lockfix/drivers/block/ll_rw_blk.c Mon Jan 8 02:40:37 2001 @@ -578,11 +578,9 @@ count = bh->b_size >> 9; sector = bh->b_rsector; - /* Uhhuh.. Nasty dead-lock possible here.. */ - if (buffer_locked(bh)) + if(test_and_set_bit(BH_Lock, &bh->b_state)) { /* Does atomic lock resolv problems? */ return; - /* Maybe the above fixes it, and maybe it doesn't boot. Life is interesting */ - lock_buffer(bh); + } if (blk_size[major]) { unsigned long maxsector = (blk_size[major][MINOR(bh->b_rdev)] << 1) + 1; diff -ur linux-2.2.19pre6/drivers/block/md.c linux-2.2.19pre6+lockfix/drivers/block/md.c --- linux-2.2.19pre6/drivers/block/md.c Tue Sep 5 02:39:16 2000 +++ linux-2.2.19pre6+lockfix/drivers/block/md.c Mon Jan 8 02:41:19 2001 @@ -778,9 +778,9 @@ int md_make_request (int minor, int rw, struct buffer_head * bh) { if (md_dev [minor].pers->make_request) { - if (buffer_locked(bh)) + if(test_and_set_bit(BH_Lock, &bh->b_state)) { /* atomic lock */ return 0; - set_bit(BH_Lock, &bh->b_state); + } if (rw == WRITE || rw == WRITEA) { if (!buffer_dirty(bh)) { bh->b_end_io(bh, test_bit(BH_Uptodate, &bh->b_state)); - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/