From: Andrew Morton Subject: Re: [PATCH] JBD: use GFP_NOFS in kmalloc Date: Wed, 19 Sep 2007 14:34:29 -0700 Message-ID: <20070919143429.ea0b37c9.akpm@linux-foundation.org> References: <20070902152801.GA19962@infradead.org> <20070903134043.GB28962@infradead.org> <20070903193308.GA7771@infradead.org> <1189796027.3841.6.camel@localhost.localdomain> <1190057391.3845.22.camel@localhost.localdomain> <1190066466.31220.5.camel@dyn9047017100.beaverton.ibm.com> <1190069851.6725.6.camel@localhost.localdomain> <20070918090407.GA671@infradead.org> <1190133347.3819.6.camel@localhost.localdomain> <1190138690.6528.23.camel@norville.austin.ibm.com> <1190163601.3819.15.camel@localhost.localdomain> <20070918191920.a2130a3c.akpm@linux-foundation.org> <1190229352.4318.12.camel@localhost.localdomain> <1190229729.4318.19.camel@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: linux-fsdevel , ext4 development , lkml To: cmm@us.ibm.com Return-path: Received: from smtp2.linux-foundation.org ([207.189.120.14]:44211 "EHLO smtp2.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751870AbXISVfH (ORCPT ); Wed, 19 Sep 2007 17:35:07 -0400 In-Reply-To: <1190229729.4318.19.camel@localhost.localdomain> Sender: linux-ext4-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org On Wed, 19 Sep 2007 12:22:09 -0700 Mingming Cao wrote: > Convert the GFP_KERNEL flag used in JBD/JBD2 to GFP_NOFS, consistent > with the rest of kmalloc flag used in the JBD/JBD2 layer. > > Signed-off-by: Mingming Cao > > --- > fs/jbd/journal.c | 6 +++--- > fs/jbd/revoke.c | 8 ++++---- > fs/jbd2/journal.c | 6 +++--- > fs/jbd2/revoke.c | 8 ++++---- > 4 files changed, 14 insertions(+), 14 deletions(-) > > Index: linux-2.6.23-rc6/fs/jbd/journal.c > =================================================================== > --- linux-2.6.23-rc6.orig/fs/jbd/journal.c 2007-09-19 11:51:10.000000000 -0700 > +++ linux-2.6.23-rc6/fs/jbd/journal.c 2007-09-19 11:51:57.000000000 -0700 > @@ -653,7 +653,7 @@ static journal_t * journal_init_common ( > journal_t *journal; > int err; > > - journal = kmalloc(sizeof(*journal), GFP_KERNEL); > + journal = kmalloc(sizeof(*journal), GFP_NOFS); > if (!journal) > goto fail; > memset(journal, 0, sizeof(*journal)); > @@ -723,7 +723,7 @@ journal_t * journal_init_dev(struct bloc > journal->j_blocksize = blocksize; > n = journal->j_blocksize / sizeof(journal_block_tag_t); > journal->j_wbufsize = n; > - journal->j_wbuf = kmalloc(n * sizeof(struct buffer_head*), GFP_KERNEL); > + journal->j_wbuf = kmalloc(n * sizeof(struct buffer_head*), GFP_NOFS); > if (!journal->j_wbuf) { > printk(KERN_ERR "%s: Cant allocate bhs for commit thread\n", > __FUNCTION__); > @@ -777,7 +777,7 @@ journal_t * journal_init_inode (struct i > /* journal descriptor can store up to n blocks -bzzz */ > n = journal->j_blocksize / sizeof(journal_block_tag_t); > journal->j_wbufsize = n; > - journal->j_wbuf = kmalloc(n * sizeof(struct buffer_head*), GFP_KERNEL); > + journal->j_wbuf = kmalloc(n * sizeof(struct buffer_head*), GFP_NOFS); > if (!journal->j_wbuf) { > printk(KERN_ERR "%s: Cant allocate bhs for commit thread\n", > __FUNCTION__); > Index: linux-2.6.23-rc6/fs/jbd/revoke.c > =================================================================== > --- linux-2.6.23-rc6.orig/fs/jbd/revoke.c 2007-09-19 11:51:30.000000000 -0700 > +++ linux-2.6.23-rc6/fs/jbd/revoke.c 2007-09-19 11:52:34.000000000 -0700 > @@ -206,7 +206,7 @@ int journal_init_revoke(journal_t *journ > while((tmp >>= 1UL) != 0UL) > shift++; > > - journal->j_revoke_table[0] = kmem_cache_alloc(revoke_table_cache, GFP_KERNEL); > + journal->j_revoke_table[0] = kmem_cache_alloc(revoke_table_cache, GFP_NOFS); > if (!journal->j_revoke_table[0]) > return -ENOMEM; > journal->j_revoke = journal->j_revoke_table[0]; > @@ -219,7 +219,7 @@ int journal_init_revoke(journal_t *journ > journal->j_revoke->hash_shift = shift; > > journal->j_revoke->hash_table = > - kmalloc(hash_size * sizeof(struct list_head), GFP_KERNEL); > + kmalloc(hash_size * sizeof(struct list_head), GFP_NOFS); > if (!journal->j_revoke->hash_table) { > kmem_cache_free(revoke_table_cache, journal->j_revoke_table[0]); > journal->j_revoke = NULL; > @@ -229,7 +229,7 @@ int journal_init_revoke(journal_t *journ > for (tmp = 0; tmp < hash_size; tmp++) > INIT_LIST_HEAD(&journal->j_revoke->hash_table[tmp]); > > - journal->j_revoke_table[1] = kmem_cache_alloc(revoke_table_cache, GFP_KERNEL); > + journal->j_revoke_table[1] = kmem_cache_alloc(revoke_table_cache, GFP_NOFS); > if (!journal->j_revoke_table[1]) { > kfree(journal->j_revoke_table[0]->hash_table); > kmem_cache_free(revoke_table_cache, journal->j_revoke_table[0]); > @@ -246,7 +246,7 @@ int journal_init_revoke(journal_t *journ > journal->j_revoke->hash_shift = shift; > > journal->j_revoke->hash_table = > - kmalloc(hash_size * sizeof(struct list_head), GFP_KERNEL); > + kmalloc(hash_size * sizeof(struct list_head), GFP_NOFS); > if (!journal->j_revoke->hash_table) { > kfree(journal->j_revoke_table[0]->hash_table); > kmem_cache_free(revoke_table_cache, journal->j_revoke_table[0]); These were all OK using GFP_KERNEL. GFP_NOFS should only be used when the caller is holding some fs locks which might cause a deadlock if that caller reentered the fs in ->writepage (and maybe put_inode and such). That isn't the case in any of the above code, which is all mount time stuff (I think). ext3/4 should be using GFP_NOFS when the caller has a transaction open, has a page locked, is holding i_mutex, etc.