From: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx>
Architectures without membarrier hooks don't need to emit the
empty membarrier_arch_switch_mm() static inline when
CONFIG_MEMBARRIER=y.
Adapt the CONFIG_MEMBARRIER=n counterpart to only emit the empty
membarrier_arch_switch_mm() for architectures with membarrier hooks.
Reported-by: Nicholas Piggin <npiggin@xxxxxxxxx>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx>
CC: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
CC: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
CC: Boqun Feng <boqun.feng@xxxxxxxxx>
CC: Andrew Hunter <ahh@xxxxxxxxxx>
CC: Maged Michael <maged.michael@xxxxxxxxx>
CC: gromer@xxxxxxxxxx
CC: Avi Kivity <avi@xxxxxxxxxxxx>
CC: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
CC: Paul Mackerras <paulus@xxxxxxxxx>
CC: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
CC: Dave Watson <davejwatson@xxxxxx>
CC: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
CC: Will Deacon <will.deacon@xxxxxxx>
CC: Andy Lutomirski <luto@xxxxxxxxxx>
CC: Ingo Molnar <mingo@xxxxxxxxxx>
CC: Alexander Viro <viro@xxxxxxxxxxxxxxxxxx>
CC: linuxppc-dev@xxxxxxxxxxxxxxxx
CC: linux-arch@xxxxxxxxxxxxxxx
Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
---
include/linux/sched/mm.h | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)
diff --git a/include/linux/sched/mm.h b/include/linux/sched/mm.h
index e4955d293687..40379edac388 100644
--- a/include/linux/sched/mm.h
+++ b/include/linux/sched/mm.h
@@ -221,10 +221,6 @@ static inline void memalloc_noreclaim_restore(unsigned int flags)
#ifdef CONFIG_ARCH_HAS_MEMBARRIER_HOOKS
#include <asm/membarrier.h>
#else
-static inline void membarrier_arch_switch_mm(struct mm_struct *prev,
- struct mm_struct *next, struct task_struct *tsk)
-{
-}
static inline void membarrier_arch_fork(struct task_struct *t,
unsigned long clone_flags)
{
@@ -253,10 +249,12 @@ static inline void membarrier_execve(struct task_struct *t)
membarrier_arch_execve(t);
}
#else
+#ifdef CONFIG_ARCH_HAS_MEMBARRIER_HOOKS
static inline void membarrier_arch_switch_mm(struct mm_struct *prev,
struct mm_struct *next, struct task_struct *tsk)
{
}
+#endif
static inline void membarrier_fork(struct task_struct *t,
unsigned long clone_flags)
{
--
2.5.2
