ARM: 6050/1: VFP: fix the SMP versions of vfp_{sync,flush}_hwstate

From: Imre Deak <imre.deak@nokia.com>

Recently the UP versions of these functions were refactored and as
a side effect it became possible to call them for the current thread.
This isn't true for the SMP versions however, so fix this up.

Signed-off-by: Imre Deak <imre.deak@nokia.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 10 insertions, 21 deletions

diff --git a/arch/arm/vfp/vfpmodule.c b/arch/arm/vfp/vfpmodule.c
index a420cb94932..315a540c7ce 100644
--- a/arch/arm/vfp/vfpmodule.c
+++ b/arch/arm/vfp/vfpmodule.c
@@ -428,26 +428,6 @@ static void vfp_pm_init(void)
 static inline void vfp_pm_init(void) { }
 #endif /* CONFIG_PM */
 
-/*
- * Synchronise the hardware VFP state of a thread other than current with the
- * saved one. This function is used by the ptrace mechanism.
- */
-#ifdef CONFIG_SMP
-void vfp_sync_hwstate(struct thread_info *thread)
-{
-}
-
-void vfp_flush_hwstate(struct thread_info *thread)
-{
-        /*
-         * On SMP systems, the VFP state is automatically saved at every
-         * context switch. We mark the thread VFP state as belonging to a
-         * non-existent CPU so that the saved one will be reloaded when
-         * needed.
-         */
-        thread->vfpstate.hard.cpu = NR_CPUS;
-}
-#else
 void vfp_sync_hwstate(struct thread_info *thread)
 {
         unsigned int cpu = get_cpu();
@@ -490,9 +470,18 @@ void vfp_flush_hwstate(struct thread_info *thread)
                 last_VFP_context[cpu] = NULL;
         }
 
+#ifdef CONFIG_SMP
+        /*
+         * For SMP we still have to take care of the case where the thread
+         * migrates to another CPU and then back to the original CPU on which
+         * the last VFP user is still the same thread. Mark the thread VFP
+         * state as belonging to a non-existent CPU so that the saved one will
+         * be reloaded in the above case.
+         */
+        thread->vfpstate.hard.cpu = NR_CPUS;
+#endif
         put_cpu();
 }
-#endif
 
 #include <linux/smp.h>