From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Date: Tue, 28 May 2019 12:56:12 +0000 (-0400)
Subject: Remove volatile, use READ/WRITE ONCE
X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=78fd8175a07ba77bc5e66600c4570cfd231df035;p=librseq.git

Remove volatile, use READ/WRITE ONCE

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

diff --git a/include/rseq/rseq.h b/include/rseq/rseq.h
index a365ac8..5aa2063 100644
--- a/include/rseq/rseq.h
+++ b/include/rseq/rseq.h
@@ -44,7 +44,7 @@
 #define RSEQ_INJECT_FAILED
 #endif
 
-extern __thread volatile struct rseq __rseq_abi;
+extern __thread struct rseq __rseq_abi;
 extern int __rseq_handled;
 
 #define rseq_likely(x)		__builtin_expect(!!(x), 1)
@@ -111,7 +111,7 @@ int rseq_available(void);
  */
 static inline int32_t rseq_current_cpu_raw(void)
 {
-	return RSEQ_ACCESS_ONCE(__rseq_abi.cpu_id);
+	return RSEQ_READ_ONCE(__rseq_abi.cpu_id);
 }
 
 /*
@@ -127,7 +127,7 @@ static inline int32_t rseq_current_cpu_raw(void)
  */
 static inline uint32_t rseq_cpu_start(void)
 {
-	return RSEQ_ACCESS_ONCE(__rseq_abi.cpu_id_start);
+	return RSEQ_READ_ONCE(__rseq_abi.cpu_id_start);
 }
 
 static inline uint32_t rseq_current_cpu(void)
@@ -143,9 +143,9 @@ static inline uint32_t rseq_current_cpu(void)
 static inline void rseq_clear_rseq_cs(void)
 {
 #ifdef __LP64__
-	__rseq_abi.rseq_cs.ptr = 0;
+	RSEQ_WRITE_ONCE(__rseq_abi.rseq_cs.ptr, 0);
 #else
-	__rseq_abi.rseq_cs.ptr.ptr32 = 0;
+	RSEQ_WRITE_ONCE(__rseq_abi.rseq_cs.ptr.ptr32, 0);
 #endif
 }
 
diff --git a/src/rseq.c b/src/rseq.c
index 033cbab..6f39f09 100644
--- a/src/rseq.c
+++ b/src/rseq.c
@@ -32,7 +32,7 @@
 
 #define ARRAY_SIZE(arr)	(sizeof(arr) / sizeof((arr)[0]))
 
-__thread volatile struct rseq __rseq_abi = {
+__thread struct rseq __rseq_abi = {
 	.cpu_id = RSEQ_CPU_ID_UNINITIALIZED,
 };
 
@@ -46,9 +46,9 @@ int __rseq_handled;
 /* Whether this library have ownership of rseq registration. */
 static int rseq_ownership;
 
-static __thread volatile uint32_t __rseq_refcount;
+static __thread uint32_t __rseq_refcount;
 
-static int sys_rseq(volatile struct rseq *rseq_abi, uint32_t rseq_len,
+static int sys_rseq(struct rseq *rseq_abi, uint32_t rseq_len,
 		    int flags, uint32_t sig)
 {
 	return syscall(__NR_rseq, rseq_abi, rseq_len, flags, sig);