From 08ed487c819d285c3f6ceafd156094102acdfec2 Mon Sep 17 00:00:00 2001 From: Anna-Maria Gleixner Date: Thu, 17 Nov 2016 19:35:39 +0100 Subject: [PATCH] x86/oprofile/nmi: Remove superfluous smp_function_call_single() Since commit 1cf4f629d9d2 ("cpu/hotplug: Move online calls to hotplugged cpu") the CPU_ONLINE and CPU_DOWN_PREPARE notifiers are always run on the hot plugged CPU, and as of commit 3b9d6da67e11 ("cpu/hotplug: Fix rollback during error-out in __cpu_disable()") the CPU_DOWN_FAILED notifier also runs on the hot plugged CPU. This patch converts the SMP functional calls into direct calls. smp_call_function_single() executes the function with interrupts disabled. This calling convention is preserved. Signed-off-by: Anna-Maria Gleixner Signed-off-by: Sebastian Andrzej Siewior Cc: Robert Richter Cc: rt@linuxtronix.de Cc: oprofile-list@lists.sf.net Link: http://lkml.kernel.org/r/20161117183541.8588-19-bigeasy@linutronix.de Signed-off-by: Thomas Gleixner --- arch/x86/oprofile/nmi_int.c | 22 ++++++++++++---------- 1 file changed, 12 insertions(+), 10 deletions(-) diff --git a/arch/x86/oprofile/nmi_int.c b/arch/x86/oprofile/nmi_int.c index 28c04123b6dd..c39172cd6c87 100644 --- a/arch/x86/oprofile/nmi_int.c +++ b/arch/x86/oprofile/nmi_int.c @@ -387,20 +387,24 @@ static void nmi_cpu_shutdown(void *dummy) nmi_cpu_restore_registers(msrs); } -static void nmi_cpu_up(void *dummy) +static void nmi_cpu_up(void) { + local_irq_disable(); if (nmi_enabled) - nmi_cpu_setup(dummy); + nmi_cpu_setup(NULL); if (ctr_running) - nmi_cpu_start(dummy); + nmi_cpu_start(NULL); + local_irq_enable(); } -static void nmi_cpu_down(void *dummy) +static void nmi_cpu_down(void) { + local_irq_disable(); if (ctr_running) - nmi_cpu_stop(dummy); + nmi_cpu_stop(NULL); if (nmi_enabled) - nmi_cpu_shutdown(dummy); + nmi_cpu_shutdown(NULL); + local_irq_enable(); } static int nmi_create_files(struct dentry *root) @@ -436,15 +440,13 @@ static int nmi_create_files(struct dentry *root) static int oprofile_cpu_notifier(struct notifier_block *b, unsigned long action, void *data) { - int cpu = (unsigned long)data; - switch (action & ~CPU_TASKS_FROZEN) { case CPU_DOWN_FAILED: case CPU_ONLINE: - smp_call_function_single(cpu, nmi_cpu_up, NULL, 0); + nmi_cpu_up(); break; case CPU_DOWN_PREPARE: - smp_call_function_single(cpu, nmi_cpu_down, NULL, 1); + nmi_cpu_down(); break; } return NOTIFY_DONE;