From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx130.postini.com [74.125.245.130]) by kanga.kvack.org (Postfix) with SMTP id 3C08B6B0044 for ; Mon, 8 Oct 2012 16:35:45 -0400 (EDT) Received: by mail-pa0-f41.google.com with SMTP id fa10so4860033pad.14 for ; Mon, 08 Oct 2012 13:35:44 -0700 (PDT) Date: Mon, 8 Oct 2012 13:35:42 -0700 (PDT) From: David Rientjes Subject: Re: mpol_to_str revisited. In-Reply-To: <20121008150949.GA15130@redhat.com> Message-ID: References: <20121008150949.GA15130@redhat.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Dave Jones , Linux Kernel , bhutchings@solarflare.com, linux-mm@kvack.org, Linus Torvalds , Andrew Morton 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, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org