diff mbox series

[4/4] selftests/rseq: Use rseq_unqual_scalar_typeof in macros

Message ID 20230627152923.133238-5-mathieu.desnoyers@efficios.com
State Accepted
Commit 2b2fe6052dd01fdb4e9a31031c2c9d8f03cf7753
Headers show
Series rseq selftests updates | expand

Commit Message

Mathieu Desnoyers June 27, 2023, 3:29 p.m. UTC 
Use rseq_unqual_scalar_typeof() rather than typeof() in macros to remove
the volatile qualifier (if there is one in the input argument), thus
generating better assembly code in those scenarios.

Also add extra brackets around the "p" parameter in RSEQ_READ_ONCE(),
RSEQ_WRITE_ONCE(), and rseq_unqual_scalar_typeof() across architectures
to preserve expectations of operator priority. Here is an example that
shows how operator priority may be an issue with missing parentheses:

    #define m(p) \
    do { \
            __typeof__(*p) v = 0; \
    } while (0)

    void fct(unsigned long long *p1)
    {
            m(p1 + 1);      /* works */
            m(1 + p1);      /* broken */
    }

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Peter Zijlstra <peterz@infradead.org>
---
 tools/testing/selftests/rseq/rseq-arm.h   | 4 ++--
 tools/testing/selftests/rseq/rseq-mips.h  | 4 ++--
 tools/testing/selftests/rseq/rseq-ppc.h   | 4 ++--
 tools/testing/selftests/rseq/rseq-riscv.h | 6 +++---
 tools/testing/selftests/rseq/rseq-s390.h  | 4 ++--
 tools/testing/selftests/rseq/rseq-x86.h   | 4 ++--
 6 files changed, 13 insertions(+), 13 deletions(-)
diff mbox series

Patch

diff --git a/tools/testing/selftests/rseq/rseq-arm.h b/tools/testing/selftests/rseq/rseq-arm.h
index 8414fc3eac15..d887b3bbe257 100644
--- a/tools/testing/selftests/rseq/rseq-arm.h
+++ b/tools/testing/selftests/rseq/rseq-arm.h
@@ -66,7 +66,7 @@ 
 
 #define rseq_smp_load_acquire(p)					\
 __extension__ ({							\
-	__typeof(*p) ____p1 = RSEQ_READ_ONCE(*p);			\
+	rseq_unqual_scalar_typeof(*(p)) ____p1 = RSEQ_READ_ONCE(*(p));	\
 	rseq_smp_mb();							\
 	____p1;								\
 })
@@ -76,7 +76,7 @@  __extension__ ({							\
 #define rseq_smp_store_release(p, v)					\
 do {									\
 	rseq_smp_mb();							\
-	RSEQ_WRITE_ONCE(*p, v);						\
+	RSEQ_WRITE_ONCE(*(p), v);					\
 } while (0)
 
 #define __RSEQ_ASM_DEFINE_TABLE(label, version, flags, start_ip,	\
diff --git a/tools/testing/selftests/rseq/rseq-mips.h b/tools/testing/selftests/rseq/rseq-mips.h
index 50b950cf9585..42ef8e946693 100644
--- a/tools/testing/selftests/rseq/rseq-mips.h
+++ b/tools/testing/selftests/rseq/rseq-mips.h
@@ -45,7 +45,7 @@ 
 
 #define rseq_smp_load_acquire(p)					\
 __extension__ ({							\
-	__typeof(*p) ____p1 = RSEQ_READ_ONCE(*p);			\
+	rseq_unqual_scalar_typeof(*(p)) ____p1 = RSEQ_READ_ONCE(*(p));	\
 	rseq_smp_mb();							\
 	____p1;								\
 })
@@ -55,7 +55,7 @@  __extension__ ({							\
 #define rseq_smp_store_release(p, v)					\
 do {									\
 	rseq_smp_mb();							\
-	RSEQ_WRITE_ONCE(*p, v);						\
+	RSEQ_WRITE_ONCE(*(p), v);					\
 } while (0)
 
 #if _MIPS_SZLONG == 64
diff --git a/tools/testing/selftests/rseq/rseq-ppc.h b/tools/testing/selftests/rseq/rseq-ppc.h
index dc9190facee9..57b160597189 100644
--- a/tools/testing/selftests/rseq/rseq-ppc.h
+++ b/tools/testing/selftests/rseq/rseq-ppc.h
@@ -23,7 +23,7 @@ 
 
 #define rseq_smp_load_acquire(p)					\
 __extension__ ({							\
-	__typeof(*p) ____p1 = RSEQ_READ_ONCE(*p);			\
+	rseq_unqual_scalar_typeof(*(p)) ____p1 = RSEQ_READ_ONCE(*(p));	\
 	rseq_smp_lwsync();						\
 	____p1;								\
 })
@@ -33,7 +33,7 @@  __extension__ ({							\
 #define rseq_smp_store_release(p, v)					\
 do {									\
 	rseq_smp_lwsync();						\
-	RSEQ_WRITE_ONCE(*p, v);						\
+	RSEQ_WRITE_ONCE(*(p), v);					\
 } while (0)
 
 /*
diff --git a/tools/testing/selftests/rseq/rseq-riscv.h b/tools/testing/selftests/rseq/rseq-riscv.h
index 17932a79e066..37e598d0a365 100644
--- a/tools/testing/selftests/rseq/rseq-riscv.h
+++ b/tools/testing/selftests/rseq/rseq-riscv.h
@@ -36,8 +36,8 @@ 
 
 #define rseq_smp_load_acquire(p)					\
 __extension__ ({							\
-	__typeof(*(p)) ____p1 = RSEQ_READ_ONCE(*(p));			\
-	RISCV_FENCE(r, rw)						\
+	rseq_unqual_scalar_typeof(*(p)) ____p1 = RSEQ_READ_ONCE(*(p));	\
+	RISCV_FENCE(r, rw);						\
 	____p1;								\
 })
 
@@ -46,7 +46,7 @@  __extension__ ({							\
 #define rseq_smp_store_release(p, v)					\
 do {									\
 	RISCV_FENCE(rw, w);						\
-	RSEQ_WRITE_ONCE(*(p), v);						\
+	RSEQ_WRITE_ONCE(*(p), v);					\
 } while (0)
 
 #define __RSEQ_ASM_DEFINE_TABLE(label, version, flags, start_ip,	\
diff --git a/tools/testing/selftests/rseq/rseq-s390.h b/tools/testing/selftests/rseq/rseq-s390.h
index 46c92598acc7..33baaa9f9997 100644
--- a/tools/testing/selftests/rseq/rseq-s390.h
+++ b/tools/testing/selftests/rseq/rseq-s390.h
@@ -15,7 +15,7 @@ 
 
 #define rseq_smp_load_acquire(p)					\
 __extension__ ({							\
-	__typeof(*p) ____p1 = RSEQ_READ_ONCE(*p);			\
+	rseq_unqual_scalar_typeof(*(p)) ____p1 = RSEQ_READ_ONCE(*(p));	\
 	rseq_barrier();							\
 	____p1;								\
 })
@@ -25,7 +25,7 @@  __extension__ ({							\
 #define rseq_smp_store_release(p, v)					\
 do {									\
 	rseq_barrier();							\
-	RSEQ_WRITE_ONCE(*p, v);						\
+	RSEQ_WRITE_ONCE(*(p), v);					\
 } while (0)
 
 #ifdef __s390x__
diff --git a/tools/testing/selftests/rseq/rseq-x86.h b/tools/testing/selftests/rseq/rseq-x86.h
index fb65ef54b0fb..a2aa428ba151 100644
--- a/tools/testing/selftests/rseq/rseq-x86.h
+++ b/tools/testing/selftests/rseq/rseq-x86.h
@@ -42,7 +42,7 @@ 
 
 #define rseq_smp_load_acquire(p)					\
 __extension__ ({							\
-	__typeof(*p) ____p1 = RSEQ_READ_ONCE(*p);			\
+	rseq_unqual_scalar_typeof(*(p)) ____p1 = RSEQ_READ_ONCE(*(p));	\
 	rseq_barrier();							\
 	____p1;								\
 })
@@ -52,7 +52,7 @@  __extension__ ({							\
 #define rseq_smp_store_release(p, v)					\
 do {									\
 	rseq_barrier();							\
-	RSEQ_WRITE_ONCE(*p, v);						\
+	RSEQ_WRITE_ONCE(*(p), v);					\
 } while (0)
 
 #define __RSEQ_ASM_DEFINE_TABLE(label, version, flags,			\