Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752763AbYKQXbO (ORCPT ); Mon, 17 Nov 2008 18:31:14 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751552AbYKQXa6 (ORCPT ); Mon, 17 Nov 2008 18:30:58 -0500 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.123]:34145 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751279AbYKQXa5 (ORCPT ); Mon, 17 Nov 2008 18:30:57 -0500 Date: Mon, 17 Nov 2008 18:30:53 -0500 (EST) From: Steven Rostedt X-X-Sender: rostedt@gandalf.stny.rr.com To: Paul Mackerras cc: LKML , Benjamin Herrenschmidt , linuxppc-dev@ozlabs.org, Linus Torvalds , Andrew Morton , Ingo Molnar , Thomas Gleixner Subject: Re: Large stack usage in fs code (especially for PPC64) In-Reply-To: <18721.60712.438025.564030@cargo.ozlabs.ibm.com> Message-ID: References: <18721.60712.438025.564030@cargo.ozlabs.ibm.com> User-Agent: Alpine 1.10 (DEB 962 2008-03-14) 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: 1935 Lines: 43 On Tue, 18 Nov 2008, Paul Mackerras wrote: > Steven Rostedt writes: > > > Here's my stack after boot up with CONFIG_IRQSTACKS set. Seems that > > softirqs still use the same stack as the process. > > They shouldn't. I don't see do_softirq in the trace, though. Which > functions did you think would be run in a softirq? It looks to me > like the deepest 10 or so functions are called at hard irq level, > within hrtimer_interrupt called from timer_interrupt. > > > root@electra ~> cat /debug/tracing/stack_trace > > Depth Size Location (59 entries) > > ----- ---- -------- > > 0) 12384 192 ftrace_call+0x4/0x14 > > 1) 12192 128 .sched_clock+0x20/0x60 > > 2) 12064 128 .sched_clock_cpu+0x34/0x50 > > 3) 11936 144 .cpu_clock+0x3c/0xa0 > > 4) 11792 144 .get_timestamp+0x2c/0x50 > > 5) 11648 144 .__touch_softlockup_watchdog+0x3c/0x60 > > 6) 11504 192 .softlockup_tick+0xe4/0x220 > > 7) 11312 128 .run_local_timers+0x34/0x50 > > 8) 11184 160 .update_process_times+0x44/0xb0 > > 9) 11024 176 .tick_sched_timer+0x8c/0x120 > > 10) 10848 160 .__run_hrtimer+0xd8/0x130 > > 11) 10688 240 .hrtimer_interrupt+0x16c/0x220 > > 12) 10448 160 .timer_interrupt+0xcc/0x110 > > 13) 10288 96 decrementer_common+0xe0/0x100 Ah, you are right. I thought I saw softirq code in there, but must have been seeing things. I need to get my eyesight checked. The other day I totally botch a hand in cards because I thought I had 3 Aces of diamonds when I really only had 2 Aces of diamonds and a Ace of hearts. -- Steve -- 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/