From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Morton Subject: [patch 15/93] ia64: pass log level as arg into ia64_do_show_stack() Date: Mon, 08 Jun 2020 21:30:41 -0700 Message-ID: <20200609043041.fM5M3O3k9%akpm@linux-foundation.org> References: <20200608212922.5b7fa74ca3f4e2444441b7f9@linux-foundation.org> Reply-To: linux-kernel@vger.kernel.org Return-path: Received: from mail.kernel.org ([198.145.29.99]:53466 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725772AbgFIEam (ORCPT ); Tue, 9 Jun 2020 00:30:42 -0400 In-Reply-To: <20200608212922.5b7fa74ca3f4e2444441b7f9@linux-foundation.org> Sender: mm-commits-owner@vger.kernel.org List-Id: mm-commits@vger.kernel.org To: akpm@linux-foundation.org, dima@arista.com, fenghua.yu@intel.com, linux-mm@kvack.org, mm-commits@vger.kernel.org, tony.luck@intel.com, torvalds@linux-foundation.org From: Dmitry Safonov Subject: ia64: pass log level as arg into ia64_do_show_stack() 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. Add log level argument to ia64_do_show_stack() as a preparation to introduce show_stack_loglvl(). Also, make ia64_do_show_stack() static as it's not used outside. [1]: https://lore.kernel.org/lkml/20190528002412.1625-1-dima@arista.com/T/#u Link: http://lkml.kernel.org/r/20200418201944.482088-16-dima@arista.com Signed-off-by: Dmitry Safonov Cc: Fenghua Yu Cc: Tony Luck Signed-off-by: Andrew Morton --- arch/ia64/include/asm/ptrace.h | 1 - arch/ia64/kernel/process.c | 13 +++++++------ 2 files changed, 7 insertions(+), 7 deletions(-) --- a/arch/ia64/include/asm/ptrace.h~ia64-pass-log-level-as-arg-into-ia64_do_show_stack +++ a/arch/ia64/include/asm/ptrace.h @@ -114,7 +114,6 @@ static inline long regs_return_value(str struct task_struct; /* forward decl */ struct unw_frame_info; /* forward decl */ - extern void ia64_do_show_stack (struct unw_frame_info *, void *); extern unsigned long ia64_get_user_rbs_end (struct task_struct *, struct pt_regs *, unsigned long *); extern long ia64_peek (struct task_struct *, struct switch_stack *, unsigned long, --- a/arch/ia64/kernel/process.c~ia64-pass-log-level-as-arg-into-ia64_do_show_stack +++ a/arch/ia64/kernel/process.c @@ -64,12 +64,13 @@ EXPORT_SYMBOL(boot_option_idle_override) void (*pm_power_off) (void); EXPORT_SYMBOL(pm_power_off); -void +static void ia64_do_show_stack (struct unw_frame_info *info, void *arg) { unsigned long ip, sp, bsp; + const char *loglvl = arg; - printk("\nCall Trace:\n"); + printk("%s\nCall Trace:\n", loglvl); do { unw_get_ip(info, &ip); if (ip == 0) @@ -77,9 +78,9 @@ ia64_do_show_stack (struct unw_frame_inf unw_get_sp(info, &sp); unw_get_bsp(info, &bsp); - printk(" [<%016lx>] %pS\n" + printk("%s [<%016lx>] %pS\n" " sp=%016lx bsp=%016lx\n", - ip, (void *)ip, sp, bsp); + loglvl, ip, (void *)ip, sp, bsp); } while (unw_unwind(info) >= 0); } @@ -87,12 +88,12 @@ void show_stack (struct task_struct *task, unsigned long *sp) { if (!task) - unw_init_running(ia64_do_show_stack, NULL); + unw_init_running(ia64_do_show_stack, (void *)KERN_DEFAULT); else { struct unw_frame_info info; unw_init_from_blocked_task(&info, task); - ia64_do_show_stack(&info, NULL); + ia64_do_show_stack(&info, (void *)KERN_DEFAULT); } } _