diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2023-05-13 00:07:22 +0300 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2023-05-15 14:44:54 +0300 |
| commit | e464640cf7af12f3c2748065936b95eae1f735ba (patch) | |
| tree | 62016093f128002212c68cd811b87ed6d46cf437 | |
| parent | 22b612e2d53f6e13ce7b55ed565a104512f0eb00 (diff) | |
| download | linux-e464640cf7af12f3c2748065936b95eae1f735ba.tar.xz | |
x86/smpboot: Remove wait for cpu_online()
Now that the core code drops sparse_irq_lock after the idle thread
synchronized, it's pointless to wait for the AP to mark itself online.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Michael Kelley <mikelley@microsoft.com>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Tested-by: Helge Deller <deller@gmx.de> # parisc
Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com> # Steam Deck
Link: https://lore.kernel.org/r/20230512205256.316417181@linutronix.de
| -rw-r--r-- | arch/x86/kernel/smpboot.c | 26 |
1 files changed, 2 insertions, 24 deletions
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index 3f731beb4d3f..4349e8ab2566 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -275,7 +275,6 @@ static void notrace start_secondary(void *unused) * half valid vector space. */ lock_vector_lock(); - /* Sync point with do_wait_cpu_online() */ set_cpu_online(smp_processor_id(), true); lapic_online(); unlock_vector_lock(); @@ -1104,20 +1103,6 @@ static int wait_cpu_initialized(unsigned int cpu) return 0; } -/* - * Bringup step three: Wait for the target AP to reach set_cpu_online() in - * start_secondary(). - */ -static void wait_cpu_online(unsigned int cpu) -{ - /* - * Wait for the AP to mark itself online, so the core caller - * can drop sparse_irq_lock. - */ - while (!cpu_online(cpu)) - schedule(); -} - static int native_kick_ap(unsigned int cpu, struct task_struct *tidle) { int apicid = apic->cpu_present_to_apicid(cpu); @@ -1164,16 +1149,9 @@ int native_cpu_up(unsigned int cpu, struct task_struct *tidle) int ret; ret = native_kick_ap(cpu, tidle); - if (ret) - goto out; - - ret = wait_cpu_initialized(cpu); - if (ret) - goto out; - - wait_cpu_online(cpu); + if (!ret) + ret = wait_cpu_initialized(cpu); -out: /* Cleanup possible dangling ends... */ if (x86_platform.legacy.warm_reset) smpboot_restore_warm_reset_vector(); |