Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754833Ab2JHUf5 (ORCPT ); Mon, 8 Oct 2012 16:35:57 -0400 Received: from mail-da0-f46.google.com ([209.85.210.46]:40996 "EHLO mail-da0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754790Ab2JHUfo (ORCPT ); Mon, 8 Oct 2012 16:35:44 -0400 Date: Mon, 8 Oct 2012 13:35:42 -0700 (PDT) From: David Rientjes X-X-Sender: rientjes@chino.kir.corp.google.com To: Dave Jones , Linux Kernel , bhutchings@solarflare.com, linux-mm@kvack.org, Linus Torvalds , Andrew Morton Subject: Re: mpol_to_str revisited. In-Reply-To: <20121008150949.GA15130@redhat.com> Message-ID: References: <20121008150949.GA15130@redhat.com> User-Agent: Alpine 2.00 (DEB 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2418 Lines: 64 On Mon, 8 Oct 2012, Dave Jones wrote: > unanswered question: why are the buffer sizes here different ? which is correct? > Given the current set of mempolicy modes and flags, it's 34, but this can change if new modes or flags are added with longer names. I see no reason why shmem shouldn't round up to the nearest power-of-2 of 64 like it already does, but 50 is certainly safe as well in task_mmu.c. > diff -durpN '--exclude-from=/home/davej/.exclude' src/git-trees/kernel/linux/fs/proc/task_mmu.c linux-dj/fs/proc/task_mmu.c > --- src/git-trees/kernel/linux/fs/proc/task_mmu.c 2012-05-31 22:32:46.778150675 -0400 > +++ linux-dj/fs/proc/task_mmu.c 2012-10-04 19:31:41.269988984 -0400 > @@ -1162,6 +1162,7 @@ static int show_numa_map(struct seq_file > struct mm_walk walk = {}; > struct mempolicy *pol; > int n; > + int ret; > char buffer[50]; > > if (!mm) > @@ -1178,7 +1179,11 @@ static int show_numa_map(struct seq_file > walk.mm = mm; > > pol = get_vma_policy(proc_priv->task, vma, vma->vm_start); > - mpol_to_str(buffer, sizeof(buffer), pol, 0); > + memset(buffer, 0, sizeof(buffer)); > + ret = mpol_to_str(buffer, sizeof(buffer), pol, 0); > + if (ret < 0) > + return 0; We should need the mpol_cond_put(pol) here before returning. > + > mpol_cond_put(pol); > > seq_printf(m, "%08lx %s", vma->vm_start, buffer); > diff -durpN '--exclude-from=/home/davej/.exclude' src/git-trees/kernel/linux/mm/shmem.c linux-dj/mm/shmem.c > --- src/git-trees/kernel/linux/mm/shmem.c 2012-10-02 15:49:51.977277944 -0400 > +++ linux-dj/mm/shmem.c 2012-10-04 19:32:28.862949907 -0400 > @@ -885,13 +885,15 @@ redirty: > static void shmem_show_mpol(struct seq_file *seq, struct mempolicy *mpol) > { > char buffer[64]; > + int ret; > > if (!mpol || mpol->mode == MPOL_DEFAULT) > return; /* show nothing */ > > - mpol_to_str(buffer, sizeof(buffer), mpol, 1); > - > - seq_printf(seq, ",mpol=%s", buffer); > + memset(buffer, 0, sizeof(buffer)); > + ret = mpol_to_str(buffer, sizeof(buffer), mpol, 1); > + if (ret > 0) > + seq_printf(seq, ",mpol=%s", buffer); > } > > static struct mempolicy *shmem_get_sbmpol(struct shmem_sb_info *sbinfo) -- 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/