[PATCH v2] arm: Hook up SYNC_CORE functionality for sys_membarrier()

Great, thank you!

On Tue, Jun 26, 2018 at 2:26 PM Mathieu Desnoyers
[off-list ref] wrote:

----- On Jun 26, 2018, at 5:42 AM, Will Deacon will.deacon at arm.com wrote:

quoted

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: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Orion Hodson <redacted>
Signed-off-by: Will Deacon <redacted>

Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Thanks!

Mathieu

quoted

---

v1 -> v2: Update arch-support.txt

.../features/sched/membarrier-sync-core/arch-support.txt          | 8 ++++----
arch/arm/Kconfig                                                  | 1 +
2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/Documentation/features/sched/membarrier-sync-core/arch-support.txt

b/Documentation/features/sched/membarrier-sync-core/arch-support.txt
index dbdf62907703..c7858dd1ea8f 100644

--- 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 54eeb8d00bc6..b0ac18547370 100644
--- 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
--

2.1.4

--
Mathieu Desnoyers
EfficiOS Inc.
http://www.efficios.com

-- 

Orion Hodson | Software Engineer | oth at google.com | +44 7505 730469