From: Mingming Cao Subject: Re: [PATCH] JBD: use GFP_NOFS in kmalloc Date: Wed, 19 Sep 2007 14:55:00 -0700 Message-ID: <1190238900.4318.26.camel@localhost.localdomain> 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> <20070919143429.ea0b37c9.akpm@linux-foundation.org> Reply-To: cmm@us.ibm.com Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Cc: linux-fsdevel , ext4 development , lkml To: Andrew Morton Return-path: In-Reply-To: <20070919143429.ea0b37c9.akpm@linux-foundation.org> Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org On Wed, 2007-09-19 at 14:34 -0700, Andrew Morton wrote: > 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). > You are right they are all occur at initialization time. > ext3/4 should be using GFP_NOFS when the caller has a transaction open, has > a page locked, is holding i_mutex, etc. > Thanks for your feedback. Mingming