[tip: sched/core] selftests/rseq: Remove volatile from __rseq_abi - tip-bot2 for Mathieu Desnoyers

From: "tip-bot2 for Mathieu Desnoyers" <tip-bot2@linutronix.de>
To: linux-tip-commits@vger.kernel.org
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
	"Peter Zijlstra (Intel)" <peterz@infradead.org>,
	x86@kernel.org, linux-kernel@vger.kernel.org
Subject: [tip: sched/core] selftests/rseq: Remove volatile from __rseq_abi
Date: Thu, 03 Feb 2022 14:33:50 -0000	[thread overview]
Message-ID: <164389883020.16921.17584681770566486508.tip-bot2@tip-bot2> (raw)
In-Reply-To: <20220124171253.22072-5-mathieu.desnoyers@efficios.com>

The following commit has been merged into the sched/core branch of tip:

Commit-ID:     94b80a19ebfe347a01301d750040a61c38200e2b
Gitweb:        https://git.kernel.org/tip/94b80a19ebfe347a01301d750040a61c38200e2b
Author:        Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
AuthorDate:    Mon, 24 Jan 2022 12:12:42 -05:00
Committer:     Peter Zijlstra <peterz@infradead.org>
CommitterDate: Wed, 02 Feb 2022 13:11:34 +01:00

selftests/rseq: Remove volatile from __rseq_abi

This is done in preparation for the selftest uplift to become compatible
with glibc-2.35.

All accesses to the __rseq_abi fields are volatile, but remove the
volatile from the TLS variable declaration, otherwise we are stuck with
volatile for the upcoming rseq_get_abi() helper.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20220124171253.22072-5-mathieu.desnoyers@efficios.com
---
 tools/testing/selftests/rseq/rseq.c | 4 ++--
 tools/testing/selftests/rseq/rseq.h | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/tools/testing/selftests/rseq/rseq.c b/tools/testing/selftests/rseq/rseq.c
index bfe1b26..1f905b6 100644
--- a/tools/testing/selftests/rseq/rseq.c
+++ b/tools/testing/selftests/rseq/rseq.c
@@ -30,7 +30,7 @@
 #include "../kselftest.h"
 #include "rseq.h"
 
-__thread volatile struct rseq_abi __rseq_abi = {
+__thread struct rseq_abi __rseq_abi = {
 	.cpu_id = RSEQ_ABI_CPU_ID_UNINITIALIZED,
 };
 
@@ -92,7 +92,7 @@ int rseq_register_current_thread(void)
 		goto end;
 	}
 	if (errno != EBUSY)
-		__rseq_abi.cpu_id = RSEQ_ABI_CPU_ID_REGISTRATION_FAILED;
+		RSEQ_WRITE_ONCE(__rseq_abi.cpu_id, RSEQ_ABI_CPU_ID_REGISTRATION_FAILED);
 	ret = -1;
 	__rseq_refcount--;
 end:
diff --git a/tools/testing/selftests/rseq/rseq.h b/tools/testing/selftests/rseq/rseq.h
index cb6bbc5..d580f8e 100644
--- a/tools/testing/selftests/rseq/rseq.h
+++ b/tools/testing/selftests/rseq/rseq.h
@@ -43,7 +43,7 @@
 #define RSEQ_INJECT_FAILED
 #endif
 
-extern __thread volatile struct rseq_abi __rseq_abi;
+extern __thread struct rseq_abi __rseq_abi;
 extern int __rseq_handled;
 
 #define rseq_likely(x)		__builtin_expect(!!(x), 1)
@@ -139,7 +139,7 @@ static inline uint32_t rseq_current_cpu(void)
 
 static inline void rseq_clear_rseq_cs(void)
 {
-	__rseq_abi.rseq_cs.arch.ptr = 0;
+	RSEQ_WRITE_ONCE(__rseq_abi.rseq_cs.arch.ptr, 0);
 }
 
 /*
