From 74c25beeb30fa32badf575a908902cbdef4d4eb4 Mon Sep 17 00:00:00 2001 From: Russell King Date: Mon, 31 Jan 2011 14:43:25 +0000 Subject: ARM: vfp: improve commentry for hotplug events Improve the documentation for the VFP hotplug notifier handler, so that people better understand what's going on there and what has been done for them. Signed-off-by: Russell King --- arch/arm/vfp/vfpmodule.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'arch/arm/vfp') diff --git a/arch/arm/vfp/vfpmodule.c b/arch/arm/vfp/vfpmodule.c index 25b89d817105..bbf3da012afd 100644 --- a/arch/arm/vfp/vfpmodule.c +++ b/arch/arm/vfp/vfpmodule.c @@ -489,8 +489,11 @@ void vfp_flush_hwstate(struct thread_info *thread) /* * VFP hardware can lose all context when a CPU goes offline. - * Safely clear our held state when a CPU has been killed, and - * re-enable access to VFP when the CPU comes back online. + * As we will be running in SMP mode with CPU hotplug, we will save the + * hardware state at every thread switch. We clear our held state when + * a CPU has been killed, indicating that the VFP hardware doesn't contain + * a threads VFP state. When a CPU starts up, we re-enable access to the + * VFP hardware. * * Both CPU_DYING and CPU_STARTING are called on the CPU which * is being offlined/onlined. -- cgit v1.2.3