From ae6a8a2ed721ecdbc15d32b2089af5ed2190adc7 Mon Sep 17 00:00:00 2001 From: Richard Cochran Date: Wed, 13 Jul 2016 17:16:57 +0000 Subject: [PATCH] x86/tboot: Convert to hotplug state machine Install the callbacks via the state machine and let the core invoke the callbacks on the already online CPUs. Signed-off-by: Richard Cochran Signed-off-by: Anna-Maria Gleixner Reviewed-by: Sebastian Andrzej Siewior Cc: Gang Wei Cc: Linus Torvalds Cc: Ning Sun Cc: Peter Zijlstra Cc: Richard L Maliszewski Cc: Shane Wang Cc: Thomas Gleixner Cc: rt@linutronix.de Cc: tboot-devel@lists.sourceforge.net Link: http://lkml.kernel.org/r/20160713153337.400227322@linutronix.de Signed-off-by: Ingo Molnar --- arch/x86/kernel/tboot.c | 25 ++++++++----------------- include/linux/cpuhotplug.h | 1 + 2 files changed, 9 insertions(+), 17 deletions(-) diff --git a/arch/x86/kernel/tboot.c b/arch/x86/kernel/tboot.c index 9b0185fbe3eb..654f6c66fe45 100644 --- a/arch/x86/kernel/tboot.c +++ b/arch/x86/kernel/tboot.c @@ -323,25 +323,16 @@ static int tboot_wait_for_aps(int num_aps) return !(atomic_read((atomic_t *)&tboot->num_in_wfs) == num_aps); } -static int tboot_cpu_callback(struct notifier_block *nfb, unsigned long action, - void *hcpu) +static int tboot_dying_cpu(unsigned int cpu) { - switch (action) { - case CPU_DYING: - atomic_inc(&ap_wfs_count); - if (num_online_cpus() == 1) - if (tboot_wait_for_aps(atomic_read(&ap_wfs_count))) - return NOTIFY_BAD; - break; + atomic_inc(&ap_wfs_count); + if (num_online_cpus() == 1) { + if (tboot_wait_for_aps(atomic_read(&ap_wfs_count))) + return -EBUSY; } - return NOTIFY_OK; + return 0; } -static struct notifier_block tboot_cpu_notifier = -{ - .notifier_call = tboot_cpu_callback, -}; - #ifdef CONFIG_DEBUG_FS #define TBOOT_LOG_UUID { 0x26, 0x25, 0x19, 0xc0, 0x30, 0x6b, 0xb4, 0x4d, \ @@ -417,8 +408,8 @@ static __init int tboot_late_init(void) tboot_create_trampoline(); atomic_set(&ap_wfs_count, 0); - register_hotcpu_notifier(&tboot_cpu_notifier); - + cpuhp_setup_state(CPUHP_AP_X86_TBOOT_DYING, "AP_X86_TBOOT_DYING", NULL, + tboot_dying_cpu); #ifdef CONFIG_DEBUG_FS debugfs_create_file("tboot_log", S_IRUSR, arch_debugfs_dir, NULL, &tboot_log_fops); diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h index c5b96d0b6fbf..070cc7f28862 100644 --- a/include/linux/cpuhotplug.h +++ b/include/linux/cpuhotplug.h @@ -53,6 +53,7 @@ enum cpuhp_state { CPUHP_AP_ARM_CORESIGHT4_STARTING, CPUHP_AP_ARM64_ISNDEP_STARTING, CPUHP_AP_LEDTRIG_STARTING, + CPUHP_AP_X86_TBOOT_DYING, CPUHP_AP_NOTIFY_STARTING, CPUHP_AP_ONLINE, CPUHP_TEARDOWN_CPU, -- 2.20.1