Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934547Ab3DORQi (ORCPT ); Mon, 15 Apr 2013 13:16:38 -0400 Received: from relay2.sgi.com ([192.48.179.30]:52373 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S932361Ab3DORQh (ORCPT ); Mon, 15 Apr 2013 13:16:37 -0400 Date: Mon, 15 Apr 2013 12:16:35 -0500 From: Robin Holt To: Ingo Molnar , Russ Anderson Cc: Shawn Guo , Oleg Nesterov , Andrew Morton , "H. Peter Anvin" , Lai Jiangshan , Linus Torvalds , Linux Kernel Mailing List , Michel Lespinasse , "Paul E. McKenney" , Paul Mackerras , Peter Zijlstra , Robin Holt , "rusty@rustcorp.com.au" , Tejun Heo , the arch/x86 maintainers , Thomas Gleixner Subject: [Patch -v3 4/4] Make reboot_cpuid a kernel parameter. Message-ID: <20130415171635.GI3672@sgi.com> References: <20130415171225.GC3658@sgi.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20130415171225.GC3658@sgi.com> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5533 Lines: 164 Moving the reboot=s<##> parameter for x86 to a kernel parameter proper. I did not find any other arch that was specifying the reboot cpu. Signed-off-by: Robin Holt To: Ingo Molnar To: Russ Anderson Cc: Shawn Guo Cc: Oleg Nesterov Cc: Andrew Morton Cc: "H. Peter Anvin" Cc: Lai Jiangshan Cc: Linus Torvalds Cc: Linux Kernel Mailing List Cc: Michel Lespinasse Cc: Oleg Nesterov Cc: "Paul E. McKenney" Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Robin Holt Cc: "rusty@rustcorp.com.au" Cc: Tejun Heo Cc: the arch/x86 maintainers Cc: Thomas Gleixner --- Documentation/kernel-parameters.txt | 2 ++ arch/x86/kernel/reboot.c | 44 ++++--------------------------------- kernel/reboot.c | 8 ++++++- 3 files changed, 13 insertions(+), 41 deletions(-) diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 4609e81..11ebb48 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -2597,6 +2597,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted. Format: [,[,...]] See arch/*/kernel/reboot.c or arch/*/kernel/process.c + reboot_cpuid= [KNL] cpuid to use for reboot/halt, etc operations. + relax_domain_level= [KNL, SMP] Set scheduler's default relax_domain_level. See Documentation/cgroups/cpusets.txt. diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c index 76fa1e9..39af130 100644 --- a/arch/x86/kernel/reboot.c +++ b/arch/x86/kernel/reboot.c @@ -49,10 +49,6 @@ int reboot_force; */ static int reboot_default = 1; -#ifdef CONFIG_SMP -static int reboot_cpu = -1; -#endif - /* * This is set if we need to go through the 'emergency' path. * When machine_emergency_restart() is called, we may be on @@ -64,11 +60,10 @@ static int reboot_emergency; bool port_cf9_safe = false; /* - * reboot=b[ios] | s[mp] | t[riple] | k[bd] | e[fi] [, [w]arm | [c]old] | p[ci] + * reboot=b[ios] | t[riple] | k[bd] | e[fi] [, [w]arm | [c]old] | p[ci] * warm Don't set the cold reboot flag * cold Set the cold reboot flag * bios Reboot by jumping through the BIOS - * smp Reboot by executing reset on BSP or other CPU * triple Force a triple fault (init) * kbd Use the keyboard controller. cold reset (default) * acpi Use the RESET_REG in the FADT @@ -95,21 +90,6 @@ static int __init reboot_setup(char *str) reboot_mode = 0; break; -#ifdef CONFIG_SMP - case 's': - if (isdigit(*(str+1))) { - reboot_cpu = (int) (*(str+1) - '0'); - if (isdigit(*(str+2))) - reboot_cpu = reboot_cpu*10 + (int)(*(str+2) - '0'); - } - /* - * We will leave sorting out the final value - * when we are ready to reboot, since we might not - * have detected BSP APIC ID or smp_num_cpu - */ - break; -#endif /* CONFIG_SMP */ - case 'b': case 'a': case 'k': @@ -614,26 +594,10 @@ void native_machine_shutdown(void) { /* Stop the cpus and apics */ #ifdef CONFIG_SMP - - /* The boot cpu is always logical cpu 0 */ - int reboot_cpu_id = 0; - - /* See if there has been given a command line override */ - if ((reboot_cpu != -1) && (reboot_cpu < nr_cpu_ids) && - cpu_online(reboot_cpu)) - reboot_cpu_id = reboot_cpu; - - /* Make certain the cpu I'm about to reboot on is online */ - if (!cpu_online(reboot_cpu_id)) - reboot_cpu_id = smp_processor_id(); - - /* Make certain I only run on the appropriate processor */ - set_cpus_allowed_ptr(current, cpumask_of(reboot_cpu_id)); - /* - * O.K Now that I'm on the appropriate processor, stop all of the - * others. Also disable the local irq to not receive the per-cpu - * timer interrupt which may trigger scheduler's load balance. + * Stop all of the others. Also disable the local irq to + * not receive the per-cpu timer interrupt which may trigger + * scheduler's load balance. */ local_irq_disable(); stop_other_cpus(); diff --git a/kernel/reboot.c b/kernel/reboot.c index 187a0d8..9fbab07 100644 --- a/kernel/reboot.c +++ b/kernel/reboot.c @@ -8,6 +8,7 @@ #include #include #include +#include #include #include #include @@ -66,13 +67,18 @@ int unregister_reboot_notifier(struct notifier_block *nb) } EXPORT_SYMBOL(unregister_reboot_notifier); +int reboot_cpuid; +core_param(reboot_cpuid, reboot_cpuid, int, 0644); + void migrate_to_reboot_cpu(void) { /* The boot cpu is always logical cpu 0 */ - int reboot_cpu_id = 0; + int reboot_cpu_id = reboot_cpuid; /* Make certain the cpu I'm about to reboot on is online */ if (!cpu_online(reboot_cpu_id)) + reboot_cpu_id = 0; + if (!cpu_online(reboot_cpu_id)) reboot_cpu_id = smp_processor_id(); /* Prevent races with other tasks migrating this task. */ -- 1.8.1.2 -- 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/