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selftests/rseq: Use rseq_unqual_scalar_typeof in macros

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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>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
This commit is contained in:
Mathieu Desnoyers 2023-06-27 11:29:23 -04:00 committed by Shuah Khan
parent 0fbbf07ce6
commit 2b2fe6052d
6 changed files with 13 additions and 13 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

4
tools/testing/selftests/rseq/rseq-arm.h
View file

@ -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, \

4
tools/testing/selftests/rseq/rseq-mips.h
View file

@ -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

4
tools/testing/selftests/rseq/rseq-ppc.h
View file

@ -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)
/*

6
tools/testing/selftests/rseq/rseq-riscv.h
View file

@ -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, \

4
tools/testing/selftests/rseq/rseq-s390.h
View file

@ -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__

4
tools/testing/selftests/rseq/rseq-x86.h
View file

@ -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, \