From ef0131b58bf95da8a5eea26f5b7856ea571ff193 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Mon, 4 Feb 2019 16:01:55 +0100 Subject: [PATCH] arm: Use common outgoing-CPU-notification code This commit removes the open-coded CPU-offline notification with new common code. In particular, this change avoids calling scheduler code using RCU from an offline CPU that RCU is ignoring. This is a minimal change. A more intrusive change might invoke the cpu_check_up_prepare() and cpu_set_state_online() functions at CPU-online time, which would allow onlining throw an error if the CPU did not go offline properly. Signed-off-by: Paul E. McKenney Cc: linux-arm-kernel@lists.infradead.org Cc: Russell King [commit rejected in mainline, but needed on Exynos platform to fix suspicious RCU usage during suspend/resume] Signed-off-by: Marek Szyprowski Change-Id: I26ba637d48fc3264e1b79507cfd0cb82bb5e6390 --- arch/arm/kernel/smp.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index 5e31c62127a0..80811a4e46f6 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -242,15 +242,13 @@ int __cpu_disable(void) return 0; } -static DECLARE_COMPLETION(cpu_died); - /* * called on the thread which is asking for a CPU to be shutdown - * waits until shutdown has completed, or it is timed out. */ void __cpu_die(unsigned int cpu) { - if (!wait_for_completion_timeout(&cpu_died, msecs_to_jiffies(5000))) { + if (!cpu_wait_death(cpu, 5)) { pr_err("CPU%u: cpu didn't die\n", cpu); return; } @@ -296,7 +294,7 @@ void arch_cpu_idle_dead(void) * this returns, power and/or clocks can be removed at any point * from this CPU and its cache by platform_cpu_kill(). */ - complete(&cpu_died); + (void)cpu_report_death(); /* * Ensure that the cache lines associated with that completion are -- 2.34.1