Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932338Ab0KLOoo (ORCPT ); Fri, 12 Nov 2010 09:44:44 -0500 Received: from mx1.redhat.com ([209.132.183.28]:1028 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932274Ab0KLOoc (ORCPT ); Fri, 12 Nov 2010 09:44:32 -0500 From: Don Zickus To: Ingo Molnar Cc: Peter Zijlstra , Robert Richter , ying.huang@intel.com, Andi Kleen , LKML , Don Zickus Subject: [PATCH 4/6] x86, NMI: Remove DIE_NMI_IPI and add priorties to handlers Date: Fri, 12 Nov 2010 09:43:51 -0500 Message-Id: <1289573033-2889-5-git-send-email-dzickus@redhat.com> In-Reply-To: <1289573033-2889-1-git-send-email-dzickus@redhat.com> References: <1289573033-2889-1-git-send-email-dzickus@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 10341 Lines: 298 When re-ordering how the NMI handles its callbacks, a conversation started asking what DIE_NMI_IPI meant. No one could answer it. Noticing that is was wasteful to call the die_chain a second time with just another argument, DIE_NMI_IPI, it was decided to nuke it and add priorities to the die_chain handlers to maintain existing behaviour. This patch replaces DIE_NMI_IPI with the appropriate option, mostly DIE_NMI. Then it adds priorities to those handlers, using a globally defined set of priorities for NMI. The thought is eventually we will just switch the nmi handlers from the die_chain to something more nmi specific. Signed-off-by: Don Zickus --- arch/x86/include/asm/kdebug.h | 1 - arch/x86/include/asm/nmi.h | 20 ++++++++++++++++++++ arch/x86/kernel/apic/hw_nmi.c | 3 +-- arch/x86/kernel/apic/x2apic_uv_x.c | 2 +- arch/x86/kernel/cpu/mcheck/mce-inject.c | 5 +++-- arch/x86/kernel/cpu/perf_event.c | 4 ++-- arch/x86/kernel/kgdb.c | 6 +----- arch/x86/kernel/reboot.c | 5 ++++- arch/x86/kernel/traps.c | 9 +-------- arch/x86/oprofile/nmi_int.c | 4 ++-- arch/x86/oprofile/nmi_timer_int.c | 4 ++-- 11 files changed, 37 insertions(+), 26 deletions(-) diff --git a/arch/x86/include/asm/kdebug.h b/arch/x86/include/asm/kdebug.h index 5bdfca8..e28ec43 100644 --- a/arch/x86/include/asm/kdebug.h +++ b/arch/x86/include/asm/kdebug.h @@ -18,7 +18,6 @@ enum die_val { DIE_TRAP, DIE_GPF, DIE_CALL, - DIE_NMI_IPI, DIE_PAGE_FAULT, DIE_NMIUNKNOWN, }; diff --git a/arch/x86/include/asm/nmi.h b/arch/x86/include/asm/nmi.h index 932f0f8..cfb6156 100644 --- a/arch/x86/include/asm/nmi.h +++ b/arch/x86/include/asm/nmi.h @@ -68,6 +68,26 @@ static inline int nmi_watchdog_active(void) } #endif +/* + * Define some priorities for the nmi notifier call chain. + * + * Create a local nmi bit that has a higher priority than + * external nmis, because the local ones are more frequent. + * + * Also setup some default high/normal/low settings for + * subsystems to registers with. Using 4 bits to seperate + * the priorities. This can go alot higher if needed be. + */ + +#define NMI_LOCAL_SHIFT 16 /* randomly picked */ +#define NMI_LOCAL_BIT (1ULL << NMI_LOCAL_SHIFT) +#define NMI_HIGH_PRIOR (1ULL << 8) +#define NMI_NORMAL_PRIOR (1ULL << 4) +#define NMI_LOW_PRIOR (1ULL << 0) +#define NMI_LOCAL_HIGH_PRIOR (NMI_LOCAL_BIT | NMI_HIGH_PRIOR) +#define NMI_LOCAL_NORMAL_PRIOR (NMI_LOCAL_BIT | NMI_NORMAL_PRIOR) +#define NMI_LOCAL_LOW_PRIOR (NMI_LOCAL_BIT | NMI_LOW_PRIOR) + void lapic_watchdog_stop(void); int lapic_watchdog_init(unsigned nmi_hz); int lapic_wd_event(unsigned nmi_hz); diff --git a/arch/x86/kernel/apic/hw_nmi.c b/arch/x86/kernel/apic/hw_nmi.c index cefd694..fabe4fe 100644 --- a/arch/x86/kernel/apic/hw_nmi.c +++ b/arch/x86/kernel/apic/hw_nmi.c @@ -53,7 +53,6 @@ arch_trigger_all_cpu_backtrace_handler(struct notifier_block *self, switch (cmd) { case DIE_NMI: - case DIE_NMI_IPI: break; default: @@ -80,7 +79,7 @@ arch_trigger_all_cpu_backtrace_handler(struct notifier_block *self, static __read_mostly struct notifier_block backtrace_notifier = { .notifier_call = arch_trigger_all_cpu_backtrace_handler, .next = NULL, - .priority = 1 + .priority = NMI_LOCAL_LOW_PRIOR, }; static int __init register_trigger_all_cpu_backtrace(void) diff --git a/arch/x86/kernel/apic/x2apic_uv_x.c b/arch/x86/kernel/apic/x2apic_uv_x.c index ed4118d..1c2e9b1 100644 --- a/arch/x86/kernel/apic/x2apic_uv_x.c +++ b/arch/x86/kernel/apic/x2apic_uv_x.c @@ -618,7 +618,7 @@ void __cpuinit uv_cpu_init(void) */ int uv_handle_nmi(struct notifier_block *self, unsigned long reason, void *data) { - if (reason != DIE_NMI_IPI) + if (reason != DIE_NMIUNKNOWN) return NOTIFY_OK; if (in_crash_kexec) diff --git a/arch/x86/kernel/cpu/mcheck/mce-inject.c b/arch/x86/kernel/cpu/mcheck/mce-inject.c index e7dbde7..a779719 100644 --- a/arch/x86/kernel/cpu/mcheck/mce-inject.c +++ b/arch/x86/kernel/cpu/mcheck/mce-inject.c @@ -25,6 +25,7 @@ #include #include #include +#include /* Update fake mce registers on current CPU. */ static void inject_mce(struct mce *m) @@ -83,7 +84,7 @@ static int mce_raise_notify(struct notifier_block *self, struct die_args *args = (struct die_args *)data; int cpu = smp_processor_id(); struct mce *m = &__get_cpu_var(injectm); - if (val != DIE_NMI_IPI || !cpumask_test_cpu(cpu, mce_inject_cpumask)) + if (val != DIE_NMI || !cpumask_test_cpu(cpu, mce_inject_cpumask)) return NOTIFY_DONE; cpumask_clear_cpu(cpu, mce_inject_cpumask); if (m->inject_flags & MCJ_EXCEPTION) @@ -95,7 +96,7 @@ static int mce_raise_notify(struct notifier_block *self, static struct notifier_block mce_raise_nb = { .notifier_call = mce_raise_notify, - .priority = 1000, + .priority = NMI_LOCAL_NORMAL_PRIOR, }; /* Inject mce on current CPU */ diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c index e98d65c..bbe3c4a 100644 --- a/arch/x86/kernel/cpu/perf_event.c +++ b/arch/x86/kernel/cpu/perf_event.c @@ -1224,7 +1224,7 @@ perf_event_nmi_handler(struct notifier_block *self, return NOTIFY_DONE; switch (cmd) { - case DIE_NMI_IPI: + case DIE_NMI: break; case DIE_NMIUNKNOWN: this_nmi = percpu_read(irq_stat.__nmi_count); @@ -1274,7 +1274,7 @@ perf_event_nmi_handler(struct notifier_block *self, static __read_mostly struct notifier_block perf_event_nmi_notifier = { .notifier_call = perf_event_nmi_handler, .next = NULL, - .priority = 1 + .priority = NMI_LOCAL_LOW_PRIOR, }; static struct event_constraint unconstrained; diff --git a/arch/x86/kernel/kgdb.c b/arch/x86/kernel/kgdb.c index ec592ca..06fd89d 100644 --- a/arch/x86/kernel/kgdb.c +++ b/arch/x86/kernel/kgdb.c @@ -521,10 +521,6 @@ static int __kgdb_notify(struct die_args *args, unsigned long cmd) } return NOTIFY_DONE; - case DIE_NMI_IPI: - /* Just ignore, we will handle the roundup on DIE_NMI. */ - return NOTIFY_DONE; - case DIE_NMIUNKNOWN: if (was_in_debug_nmi[raw_smp_processor_id()]) { was_in_debug_nmi[raw_smp_processor_id()] = 0; @@ -602,7 +598,7 @@ static struct notifier_block kgdb_notifier = { /* * Lowest-prio notifier priority, we want to be notified last: */ - .priority = -INT_MAX, + .priority = NMI_LOCAL_LOW_PRIOR, }; /** diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c index c495aa8..fc7aae1 100644 --- a/arch/x86/kernel/reboot.c +++ b/arch/x86/kernel/reboot.c @@ -18,6 +18,7 @@ #include #include #include +#include #ifdef CONFIG_X86_32 # include @@ -747,7 +748,7 @@ static int crash_nmi_callback(struct notifier_block *self, { int cpu; - if (val != DIE_NMI_IPI) + if (val != DIE_NMI) return NOTIFY_OK; cpu = raw_smp_processor_id(); @@ -778,6 +779,8 @@ static void smp_send_nmi_allbutself(void) static struct notifier_block crash_nmi_nb = { .notifier_call = crash_nmi_callback, + /* we want to be the first one called */ + .priority = NMI_LOCAL_HIGH_PRIOR+1, }; /* Halt all other CPUs, calling the specified function on each of them diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index e63bf59..79b9b2f 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -395,8 +395,7 @@ static notrace __kprobes void default_do_nmi(struct pt_regs *regs) * CPU-specific NMI: send to specific CPU or NMI sources must * be processed on specific CPU */ - if (notify_die(DIE_NMI_IPI, "nmi_ipi", regs, 0, 2, SIGINT) - == NOTIFY_STOP) + if (notify_die(DIE_NMI, "nmi", regs, 0, 2, SIGINT) == NOTIFY_STOP) return; /* Non-CPU-specific NMI: NMI sources can be processed on any CPU */ @@ -405,9 +404,6 @@ static notrace __kprobes void default_do_nmi(struct pt_regs *regs) if (!cpu) { reason = get_nmi_reason(); if (reason & NMI_REASON_MASK) { - if (notify_die(DIE_NMI, "nmi", regs, reason, 2, SIGINT) - == NOTIFY_STOP) - return; if (reason & NMI_REASON_SERR) pci_serr_error(reason, regs); else if (reason & NMI_REASON_IOCHK) @@ -423,9 +419,6 @@ static notrace __kprobes void default_do_nmi(struct pt_regs *regs) } } - if (notify_die(DIE_NMI, "nmi", regs, 0, 2, SIGINT) == NOTIFY_STOP) - return; - #if defined(CONFIG_X86_LOCAL_APIC) && !defined(CONFIG_LOCKUP_DETECTOR) if (nmi_watchdog_tick(regs, reason)) return; diff --git a/arch/x86/oprofile/nmi_int.c b/arch/x86/oprofile/nmi_int.c index ee7ff0e..e476044 100644 --- a/arch/x86/oprofile/nmi_int.c +++ b/arch/x86/oprofile/nmi_int.c @@ -64,7 +64,7 @@ static int profile_exceptions_notify(struct notifier_block *self, int ret = NOTIFY_DONE; switch (val) { - case DIE_NMI_IPI: + case DIE_NMI: if (ctr_running) model->check_ctrs(args->regs, &__get_cpu_var(cpu_msrs)); else if (!nmi_enabled) @@ -360,7 +360,7 @@ static void nmi_cpu_setup(void *dummy) static struct notifier_block profile_exceptions_nb = { .notifier_call = profile_exceptions_notify, .next = NULL, - .priority = 2 + .priority = NMI_LOCAL_LOW_PRIOR, }; static void nmi_cpu_restore_registers(struct op_msrs *msrs) diff --git a/arch/x86/oprofile/nmi_timer_int.c b/arch/x86/oprofile/nmi_timer_int.c index ab72a21..5f14fcb 100644 --- a/arch/x86/oprofile/nmi_timer_int.c +++ b/arch/x86/oprofile/nmi_timer_int.c @@ -25,7 +25,7 @@ static int profile_timer_exceptions_notify(struct notifier_block *self, int ret = NOTIFY_DONE; switch (val) { - case DIE_NMI_IPI: + case DIE_NMI: oprofile_add_sample(args->regs, 0); ret = NOTIFY_STOP; break; @@ -38,7 +38,7 @@ static int profile_timer_exceptions_notify(struct notifier_block *self, static struct notifier_block profile_timer_exceptions_nb = { .notifier_call = profile_timer_exceptions_notify, .next = NULL, - .priority = 0 + .priority = NMI_LOW_PRIOR, }; static int timer_start(void) -- 1.7.2.3 -- 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/