From 2b2fe6052dd01fdb4e9a31031c2c9d8f03cf7753 Mon Sep 17 00:00:00 2001 From: Mathieu Desnoyers Date: Tue, 27 Jun 2023 11:29:23 -0400 Subject: selftests/rseq: Use rseq_unqual_scalar_typeof in macros 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 Cc: Peter Zijlstra Signed-off-by: Shuah Khan --- tools/testing/selftests/rseq/rseq-mips.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'tools/testing/selftests/rseq/rseq-mips.h') 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 -- cgit