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 <npig...@gmail.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoy...@efficios.com>
CC: Peter Zijlstra <pet...@infradead.org>
CC: Paul E. McKenney <paul...@linux.vnet.ibm.com>
CC: Boqun Feng <boqun.f...@gmail.com>
CC: Andrew Hunter <a...@google.com>
CC: Maged Michael <maged.mich...@gmail.com>
CC: gro...@google.com
CC: Avi Kivity <a...@scylladb.com>
CC: Benjamin Herrenschmidt <b...@kernel.crashing.org>
CC: Paul Mackerras <pau...@samba.org>
CC: Michael Ellerman <m...@ellerman.id.au>
CC: Dave Watson <davejwat...@fb.com>
CC: Alan Stern <st...@rowland.harvard.edu>
CC: Will Deacon <will.dea...@arm.com>
CC: Andy Lutomirski <l...@kernel.org>
CC: Ingo Molnar <mi...@redhat.com>
CC: Alexander Viro <v...@zeniv.linux.org.uk>
CC: linuxppc-...@lists.ozlabs.org
CC: linux-a...@vger.kernel.org
---
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 d5a9ab8f3836..b2767ecb21a8 100644
--- a/include/linux/sched/mm.h
+++ b/include/linux/sched/mm.h
@@ -215,10 +215,6 @@ 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)
{
@@ -247,10 +243,12 @@ 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)
{
--
2.11.0
