[PATCH v3 03/13] task_isolation: add instruction synchronization memory barrier

From: Alex Belits
Date: Thu Apr 09 2020 - 11:18:26 EST


Some architectures implement memory synchronization instructions for instruction cache. Make a separate kind of barrier that calls them.

Signed-off-by: Alex Belits <abelits@xxxxxxxxxxx>
---
arch/arm/include/asm/barrier.h | 2 ++
arch/arm64/include/asm/barrier.h | 2 ++
include/asm-generic/barrier.h | 4 ++++
3 files changed, 8 insertions(+)

diff --git a/arch/arm/include/asm/barrier.h b/arch/arm/include/asm/barrier.h
index 83ae97c049d9..6def62c95937 100644
--- a/arch/arm/include/asm/barrier.h
+++ b/arch/arm/include/asm/barrier.h
@@ -64,12 +64,14 @@ extern void arm_heavy_mb(void);
#define mb() __arm_heavy_mb()
#define rmb() dsb()
#define wmb() __arm_heavy_mb(st)
+#define imb() isb()
#define dma_rmb() dmb(osh)
#define dma_wmb() dmb(oshst)
#else
#define mb() barrier()
#define rmb() barrier()
#define wmb() barrier()
+#define imb() barrier()
#define dma_rmb() barrier()
#define dma_wmb() barrier()
#endif
diff --git a/arch/arm64/include/asm/barrier.h b/arch/arm64/include/asm/barrier.h
index 7d9cc5ec4971..12a7dbd68bed 100644
--- a/arch/arm64/include/asm/barrier.h
+++ b/arch/arm64/include/asm/barrier.h
@@ -45,6 +45,8 @@
#define rmb() dsb(ld)
#define wmb() dsb(st)

+#define imb() isb()
+
#define dma_rmb() dmb(oshld)
#define dma_wmb() dmb(oshst)

diff --git a/include/asm-generic/barrier.h b/include/asm-generic/barrier.h
index 85b28eb80b11..d5a822fb3e92 100644
--- a/include/asm-generic/barrier.h
+++ b/include/asm-generic/barrier.h
@@ -46,6 +46,10 @@
#define dma_wmb() wmb()
#endif

+#ifndef imb
+#define imb barrier()
+#endif
+
#ifndef read_barrier_depends
#define read_barrier_depends() do { } while (0)
#endif
--
2.20.1