ARM: 8777/1: Hook up SYNC_CORE functionality for sys_membarrier()

Exception return implies context synchronization, so we can hook up the
SYNC_CORE option to sys_membarrier() simply by selecting the Kconfig option,
just like we've done for arm64 already.

Cc: Orion Hodson <oth@google.com>
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

diff --git a/Documentation/features/sched/membarrier-sync-core/arch-support.txt b/Documentation/features/sched/membarrier-sync-core/arch-support.txt
index dbdf629..c7858dd 100644 (file)
--- a/Documentation/features/sched/membarrier-sync-core/arch-support.txt
+++ b/Documentation/features/sched/membarrier-sync-core/arch-support.txt
@@ -5,10 +5,10 @@
 #
 # Architecture requirements
 #
-# * arm64
+# * arm/arm64
 #
-# Rely on eret context synchronization when returning from IPI handler, and
-# when returning to user-space.
+# Rely on implicit context synchronization as a result of exception return
+# when returning from IPI handler, and when returning to user-space.
 #
 # * x86
 #
@@ -31,7 +31,7 @@
     -----------------------
     |       alpha: | TODO |
     |         arc: | TODO |
-    |         arm: | TODO |
+    |         arm: |  ok  |
     |       arm64: |  ok  |
     |         c6x: | TODO |
     |       h8300: | TODO |

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 54eeb8d..b0ac185 100644 (file)
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -9,6 +9,7 @@ config ARM
        select ARCH_HAS_ELF_RANDOMIZE
        select ARCH_HAS_FORTIFY_SOURCE
        select ARCH_HAS_KCOV
+       select ARCH_HAS_MEMBARRIER_SYNC_CORE
        select ARCH_HAS_PTE_SPECIAL if ARM_LPAE
        select ARCH_HAS_PHYS_TO_DMA
        select ARCH_HAS_SET_MEMORY