From patchwork Mon Aug 5 19:21:17 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Paul E. McKenney" X-Patchwork-Id: 13753978 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id EDF3F143C6E; Mon, 5 Aug 2024 19:21:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722885682; cv=none; b=etHJ7ny2M1oLXSQK15mRc0sk/PymhAMdtSg5wzauAh90hkL55N9J2oXKO7P2Gy9N+3soKSfghKMhoYz979XsA3i1PGD7mLSQz9JaslVLZRjAgwr1JtuzoNe2MyQlx0WAHItR8+TDhCu/kmk8/CZbyJ7xYOwU2MJWHhuNbdQ4xas= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722885682; c=relaxed/simple; bh=SsfSYlvMJfbrFJhxWSLRoEWcjcncMnxVxwE9E1US2+0=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=etEP9cbzgFTwfVsRtpxHvfFymJIH3htKu7PusLhoOpjOIt/lLOXSCk2i1KBJXjlqlPqw9EbApNOYi3lakbKKxdDet7sAglMUVVUV4i7P0XDnQYRWGxZ9Hu9bk1E0HMkc5Vj+aHuUqU35ggCvux/mz0hKrVMF2jp5OlGu9m1G6S4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ZairQtTn; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="ZairQtTn" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8C592C32782; Mon, 5 Aug 2024 19:21:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1722885681; bh=SsfSYlvMJfbrFJhxWSLRoEWcjcncMnxVxwE9E1US2+0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ZairQtTnGfrM8IsiBq71qJecW1kAYKoiw1mpOCVFzhcp0z+L0X8x1VjPgRNexVi6f 8dNooCLXYg89HV1K9eqYdLHzBidYZwlAOEMNXFkTC7Op4DmGfpDSo5sQPUiEdQif2B oU0qTkenvvqwDkugiHSAdwpzafTmDvT1HKSZxk6Lc9+HOKS2LHmemDLh5aDTX6CbHL z2xTQm1U4txlS4aUH4Y8lBM3vLIpPNptvjafVM+s2ZBPqHl40cnEeKxs9r8ECBnY9F io31MjG/bZkCIt5+AXzgPRQvDlRAO8FsgyPApEDpo/2ET85G4DdXtKSkw08a4OlzIx s0Mj/Zrfo14tQ== Received: by paulmck-ThinkPad-P17-Gen-1.home (Postfix, from userid 1000) id 49204CE0A6F; Mon, 5 Aug 2024 12:21:21 -0700 (PDT) From: "Paul E. McKenney" To: linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org Cc: elver@google.com, akpm@linux-foundation.org, tglx@linutronix.de, peterz@infradead.org, torvalds@linux-foundation.org, arnd@arndb.de, geert@linux-m68k.org, palmer@rivosinc.com, mhiramat@kernel.org, linux-sh@vger.kernel.org, linux-snps-arc@lists.infradead.org, "Paul E. McKenney" , Yujie Liu , Andi Shyti Subject: [PATCH cmpxchg 1/3] xtensa: Emulate one-byte cmpxchg Date: Mon, 5 Aug 2024 12:21:17 -0700 Message-Id: <20240805192119.56816-1-paulmck@kernel.org> X-Mailer: git-send-email 2.40.1 In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-sh@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Use the new cmpxchg_emu_u8() to emulate one-byte cmpxchg() on xtensa. [ paulmck: Apply kernel test robot feedback. ] [ paulmck: Drop two-byte support per Arnd Bergmann feedback. ] [ Apply Geert Uytterhoeven feedback. ] Signed-off-by: Paul E. McKenney Tested-by: Yujie Liu Cc: Andi Shyti Cc: Geert Uytterhoeven Cc: Arnd Bergmann Cc: "Peter Zijlstra (Intel)" --- arch/xtensa/Kconfig | 1 + arch/xtensa/include/asm/cmpxchg.h | 2 ++ 2 files changed, 3 insertions(+) diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig index f200a4ec044e6..d3db28f2f8110 100644 --- a/arch/xtensa/Kconfig +++ b/arch/xtensa/Kconfig @@ -14,6 +14,7 @@ config XTENSA select ARCH_HAS_DMA_SET_UNCACHED if MMU select ARCH_HAS_STRNCPY_FROM_USER if !KASAN select ARCH_HAS_STRNLEN_USER + select ARCH_NEED_CMPXCHG_1_EMU select ARCH_USE_MEMTEST select ARCH_USE_QUEUED_RWLOCKS select ARCH_USE_QUEUED_SPINLOCKS diff --git a/arch/xtensa/include/asm/cmpxchg.h b/arch/xtensa/include/asm/cmpxchg.h index 675a11ea8de76..95e33a913962d 100644 --- a/arch/xtensa/include/asm/cmpxchg.h +++ b/arch/xtensa/include/asm/cmpxchg.h @@ -15,6 +15,7 @@ #include #include +#include /* * cmpxchg @@ -74,6 +75,7 @@ static __inline__ unsigned long __cmpxchg(volatile void *ptr, unsigned long old, unsigned long new, int size) { switch (size) { + case 1: return cmpxchg_emu_u8(ptr, old, new); case 4: return __cmpxchg_u32(ptr, old, new); default: __cmpxchg_called_with_bad_pointer(); return old;