From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1763368AbZLPX5F (ORCPT ); Wed, 16 Dec 2009 18:57:05 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1763377AbZLPX4m (ORCPT ); Wed, 16 Dec 2009 18:56:42 -0500 Received: from mx1.redhat.com ([209.132.183.28]:24143 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1761723AbZLPX4i (ORCPT ); Wed, 16 Dec 2009 18:56:38 -0500 Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 From: David Howells Subject: [PATCH 2/6] NOMMU: Provide per-task stack usage through /proc for NOMMU To: torvalds@osdl.org, akpm@linux-foundation.org Cc: dhowells@redhat.com, vapier@gentoo.org, lethal@linux-sh.org, linux-kernel@vger.kernel.org, uclinux-dev@uclinux.org, David Howells , Mike Frysinger , Stefani Seibold , Paul Mundt , Robin Getz Date: Wed, 16 Dec 2009 23:56:03 +0000 Message-ID: <20091216235603.4310.71243.stgit@warthog.procyon.org.uk> In-Reply-To: <20091216235558.4310.19365.stgit@warthog.procyon.org.uk> References: <20091216235558.4310.19365.stgit@warthog.procyon.org.uk> User-Agent: StGIT/0.14.3 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Make it possible to get the per-task stack usage through /proc on a NOMMU system. The MMU-mode routine can't be used because walk_page_range() doesn't work on NOMMU. It can be tested to show the stack usages of non-kernel-thread processes: # grep "Stack usage:" /proc/*/status | grep -v "0 kB" /proc/1/status:Stack usage: 2 kB /proc/57/status:Stack usage: 3 kB /proc/58/status:Stack usage: 1 kB /proc/59/status:Stack usage: 3 kB /proc/60/status:Stack usage: 5 kB /proc/self/status:Stack usage: 1 kB I've only tested it with ELF-FDPIC, though it should work with FLAT too. Signed-off-by: David Howells Signed-off-by: Mike Frysinger Cc: Stefani Seibold Cc: Paul Mundt Cc: Robin Getz --- fs/proc/array.c | 20 +++++++++++++++++--- 1 files changed, 17 insertions(+), 3 deletions(-) diff --git a/fs/proc/array.c b/fs/proc/array.c index 4badde1..c67251e 100644 --- a/fs/proc/array.c +++ b/fs/proc/array.c @@ -387,8 +387,7 @@ static inline unsigned long get_stack_usage_in_bytes(struct vm_area_struct *vma, return ss.usage; } -static inline void task_show_stack_usage(struct seq_file *m, - struct task_struct *task) +static void task_show_stack_usage(struct seq_file *m, struct task_struct *task) { struct vm_area_struct *vma; struct mm_struct *mm = get_task_mm(task); @@ -404,9 +403,24 @@ static inline void task_show_stack_usage(struct seq_file *m, mmput(mm); } } -#else +#else /* CONFIG_MMU */ +/* + * Calculate the size of a NOMMU process's stack + */ static void task_show_stack_usage(struct seq_file *m, struct task_struct *task) { + unsigned long sp, base, usage; + + base = task->stack_start; + sp = KSTK_ESP(task); + +#ifdef CONFIG_STACK_GROWSUP + usage = sp - base; +#else + usage = base - sp; +#endif + + seq_printf(m, "Stack usage:\t%lu kB\n", (usage + 1023) >> 10); } #endif /* CONFIG_MMU */