From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5F7D7C433E2 for ; Tue, 9 Jun 2020 04:30:07 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 1A990207F9 for ; Tue, 9 Jun 2020 04:30:07 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="E8Qs0qua" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1A990207F9 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id BBA716B0008; Tue, 9 Jun 2020 00:30:06 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id B1A6C6B0007; Tue, 9 Jun 2020 00:30:06 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 969BA6B000A; Tue, 9 Jun 2020 00:30:06 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0222.hostedemail.com [216.40.44.222]) by kanga.kvack.org (Postfix) with ESMTP id 7EC836B0007 for ; Tue, 9 Jun 2020 00:30:06 -0400 (EDT) Received: from smtpin29.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 4053B2493 for ; Tue, 9 Jun 2020 04:30:06 +0000 (UTC) X-FDA: 76908396012.29.paint74_45030a126dbf Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin29.hostedemail.com (Postfix) with ESMTP id 211EF1802EAA0 for ; Tue, 9 Jun 2020 04:30:06 +0000 (UTC) X-HE-Tag: paint74_45030a126dbf X-Filterd-Recvd-Size: 5242 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf22.hostedemail.com (Postfix) with ESMTP for ; Tue, 9 Jun 2020 04:30:05 +0000 (UTC) Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 8AEFC20812; Tue, 9 Jun 2020 04:30:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591677004; bh=RKFxr8ggqNUV814x7pW1O7bTYJ+uedOQQEjXUiE1iRM=; h=Date:From:To:Subject:In-Reply-To:From; b=E8Qs0quahxLSpxU+cLIDnMsqSIQN5gDw75kkRysrj+zAokWyB/POT0OA1mL9FBBDz aXOQNv5NyLp6kA5fZzqW9oEeX98RVaKG1W5yJoPWH/9IuQegMs/G1O5OkBybd3Akvu y6RGPKjKeENlAu/C90E3dhXovisPtUUzRI1v/H8s= Date: Mon, 08 Jun 2020 21:30:04 -0700 From: Andrew Morton To: akpm@linux-foundation.org, dima@arista.com, linux-mm@kvack.org, mm-commits@vger.kernel.org, torvalds@linux-foundation.org, vgupta@synopsys.com Subject: [patch 03/93] arc: add show_stack_loglvl() Message-ID: <20200609043004.rHPY8NSgU%akpm@linux-foundation.org> In-Reply-To: <20200608212922.5b7fa74ca3f4e2444441b7f9@linux-foundation.org> User-Agent: s-nail v14.8.16 X-Rspamd-Queue-Id: 211EF1802EAA0 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam03 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Dmitry Safonov Subject: arc: add show_stack_loglvl() Currently, the log-level of show_stack() depends on a platform realization. It creates situations where the headers are printed with lower log level or higher than the stacktrace (depending on a platform or user). Furthermore, it forces the logic decision from user to an architecture side. In result, some users as sysrq/kdb/etc are doing tricks with temporary rising console_loglevel while printing their messages. And in result it not only may print unwanted messages from other CPUs, but also omit printing at all in the unlucky case where the printk() was deferred. Introducing log-level parameter and KERN_UNSUPPRESSED [1] seems an easier approach than introducing more printk buffers. Also, it will consolidate printings with headers. Introduce show_stack_loglvl(), that eventually will substitute show_stack(). As a good side-effect header "Stack Trace:" is now printed with the same log level as the rest of backtrace. [1]: https://lore.kernel.org/lkml/20190528002412.1625-1-dima@arista.com/T/#u Link: http://lkml.kernel.org/r/20200418201944.482088-4-dima@arista.com Signed-off-by: Dmitry Safonov Cc: Vineet Gupta Signed-off-by: Andrew Morton --- arch/arc/include/asm/bug.h | 3 ++- arch/arc/kernel/stacktrace.c | 21 +++++++++++++++------ arch/arc/kernel/troubleshoot.c | 2 +- 3 files changed, 18 insertions(+), 8 deletions(-) --- a/arch/arc/include/asm/bug.h~arc-add-show_stack_loglvl +++ a/arch/arc/include/asm/bug.h @@ -13,7 +13,8 @@ struct task_struct; void show_regs(struct pt_regs *regs); -void show_stacktrace(struct task_struct *tsk, struct pt_regs *regs); +void show_stacktrace(struct task_struct *tsk, struct pt_regs *regs, + const char *loglvl); void show_kernel_fault_diag(const char *str, struct pt_regs *regs, unsigned long address); void die(const char *str, struct pt_regs *regs, unsigned long address); --- a/arch/arc/kernel/stacktrace.c~arc-add-show_stack_loglvl +++ a/arch/arc/kernel/stacktrace.c @@ -158,9 +158,11 @@ arc_unwind_core(struct task_struct *tsk, /* Call-back which plugs into unwinding core to dump the stack in * case of panic/OOPs/BUG etc */ -static int __print_sym(unsigned int address, void *unused) +static int __print_sym(unsigned int address, void *arg) { - printk(" %pS\n", (void *)address); + const char *loglvl = arg; + + printk("%s %pS\n", loglvl, (void *)address); return 0; } @@ -217,17 +219,24 @@ static int __get_first_nonsched(unsigned *------------------------------------------------------------------------- */ -noinline void show_stacktrace(struct task_struct *tsk, struct pt_regs *regs) +noinline void show_stacktrace(struct task_struct *tsk, struct pt_regs *regs, + const char *loglvl) { - pr_info("\nStack Trace:\n"); - arc_unwind_core(tsk, regs, __print_sym, NULL); + printk("%s\nStack Trace:\n", loglvl); + arc_unwind_core(tsk, regs, __print_sym, (void *)loglvl); } EXPORT_SYMBOL(show_stacktrace); /* Expected by sched Code */ +void show_stack_loglvl(struct task_struct *tsk, unsigned long *sp, + const char *loglvl) +{ + show_stacktrace(tsk, NULL, loglvl); +} + void show_stack(struct task_struct *tsk, unsigned long *sp) { - show_stacktrace(tsk, NULL); + show_stack_loglvl(tsk, sp, KERN_DEFAULT); } /* Another API expected by schedular, shows up in "ps" as Wait Channel --- a/arch/arc/kernel/troubleshoot.c~arc-add-show_stack_loglvl +++ a/arch/arc/kernel/troubleshoot.c @@ -240,5 +240,5 @@ void show_kernel_fault_diag(const char * /* Show stack trace if this Fatality happened in kernel mode */ if (!user_mode(regs)) - show_stacktrace(current, regs); + show_stacktrace(current, regs, KERN_DEFAULT); } _