From: Josef Bacik Subject: [PATCH] fix softlockups in ext2/3 when trying to allocate blocks Date: Mon, 6 Jul 2009 15:47:39 -0400 Message-ID: <20090706194739.GB19798@dhcp231-156.rdu.redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: emcnabb@redhat.com, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org To: linux-ext4@vger.kernel.org Return-path: Received: from mx2.redhat.com ([66.187.237.31]:47325 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753017AbZGFTnV (ORCPT ); Mon, 6 Jul 2009 15:43:21 -0400 Content-Disposition: inline Sender: linux-ext4-owner@vger.kernel.org List-ID: This isn't a huge deal, but using a big beefy box with more CPUs than what is sane, you can get a nice flood of softlockup messages when running heavy multi-threaded io tests on ext2/3. The processors compete for blocks from the allocator, so they will loop quite a bit trying to get their allocation. This patch simply makes sure that we reschedule if need be. This made the softlockup messages disappear whereas before they happened almost immediately. Thanks, Tested-by: Evan McNabb Signed-off-by: Josef Bacik --- fs/ext2/balloc.c | 1 + fs/ext3/balloc.c | 2 ++ 2 files changed, 3 insertions(+), 0 deletions(-) diff --git a/fs/ext2/balloc.c b/fs/ext2/balloc.c index 7f8d2e5..17dd55f 100644 --- a/fs/ext2/balloc.c +++ b/fs/ext2/balloc.c @@ -1176,6 +1176,7 @@ ext2_try_to_allocate_with_rsv(struct super_block *sb, unsigned int group, break; /* succeed */ } num = *count; + cond_resched(); } return ret; } diff --git a/fs/ext3/balloc.c b/fs/ext3/balloc.c index 27967f9..cffc8cd 100644 --- a/fs/ext3/balloc.c +++ b/fs/ext3/balloc.c @@ -735,6 +735,7 @@ bitmap_search_next_usable_block(ext3_grpblk_t start, struct buffer_head *bh, struct journal_head *jh = bh2jh(bh); while (start < maxblocks) { + cond_resched(); next = ext3_find_next_zero_bit(bh->b_data, maxblocks, start); if (next >= maxblocks) return -1; @@ -1391,6 +1392,7 @@ ext3_try_to_allocate_with_rsv(struct super_block *sb, handle_t *handle, break; /* succeed */ } num = *count; + cond_resched(); } out: if (ret >= 0) { -- 1.6.2.2