From nobody Wed Dec 17 12:43:46 2025 Received: from cstnet.cn (smtp84.cstnet.cn [159.226.251.84]) (using TLSv1.2 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0FFEB27FB37 for ; Fri, 10 Oct 2025 23:36:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=159.226.251.84 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760139415; cv=none; b=D/K9pDxW0HUtdkD9XJTCmkLKL08JyuMgM/2aNNfzHJ4Pm553D3TFPTw77yDqZe7LZ0Hj0jwI4BydbuDV+vBY+R/5Xmtx6rBvaqJZxppTTOzq34sh300B+9nM8AsEnrJHLLZiiK+GcZP8V38hyl8TCTcZV6KXtpfGiI2Lucbzl7s= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760139415; c=relaxed/simple; bh=yn549GC5MTVOmDeuKYorX8vzwQVzn0ayeG7Hx9nghZg=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=iEFp5jr83cbEhvozc84GjqOdS0S66wPyMxG0u39K4bqxTrFNkVO+MqiKKb8+My/mpKK3G2Cc54zelq6IePZ09MaLtRhbNwpIhNC6vsdojKJMpE3r8Mmq0pcAJVJGGM7T9AUxMZvNoew1vJ114uur0xg4d0lXetmLNDQTkF8J8es= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=iscas.ac.cn; spf=pass smtp.mailfrom=iscas.ac.cn; arc=none smtp.client-ip=159.226.251.84 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=iscas.ac.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=iscas.ac.cn Received: from [127.0.0.2] (unknown [114.241.81.247]) by APP-05 (Coremail) with SMTP id zQCowADHaxVUmOloXC2IDQ--.41211S3; Sat, 11 Oct 2025 07:35:48 +0800 (CST) From: Vivian Wang Date: Sat, 11 Oct 2025 07:35:43 +0800 Subject: [PATCH v3 1/5] riscv: pgtable: Use __riscv_has_extension_unlikely Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20251011-riscv-altn-helper-wip-v3-1-d40ddaa1985a@iscas.ac.cn> References: <20251011-riscv-altn-helper-wip-v3-0-d40ddaa1985a@iscas.ac.cn> In-Reply-To: <20251011-riscv-altn-helper-wip-v3-0-d40ddaa1985a@iscas.ac.cn> To: Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexandre Ghiti , Yury Norov , Rasmus Villemoes , Paul Walmsley Cc: Charlie Jenkins , Xiao Wang , =?utf-8?q?Christoph_M=C3=BCllner?= , Vivian Wang , Vivian Wang , linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org X-Mailer: b4 0.14.2 X-CM-TRANSID: zQCowADHaxVUmOloXC2IDQ--.41211S3 X-Coremail-Antispam: 1UD129KBjvJXoWxJFWUKFW8uF4rXr1fJF45trb_yoW5Cw1Upr Z3CasxWrWrCw1xurZ2yr4DCr45Z39ag3W3Kr1S93WrAr4akw42vrnxJ3Wayry8Ja97X348 KF4akr45W3W3Ar7anT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUmF14x267AKxVWrJVCq3wAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_Jr4l82xGYIkIc2 x26xkF7I0E14v26r4j6ryUM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8wA2z4x0 Y4vE2Ix0cI8IcVAFwI0_Jr0_JF4l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr0_Cr1l84 ACjcxK6I8E87Iv67AKxVW8Jr0_Cr1UM28EF7xvwVC2z280aVCY1x0267AKxVW8Jr0_Cr1U M2AIxVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F40Ex7xfMcIj6xIIjx v20xvE14v26r1j6r18McIj6I8E87Iv67AKxVWUJVW8JwAm72CE4IkC6x0Yz7v_Jr0_Gr1l F7xvr2IYc2Ij64vIr41lF7I21c0EjII2zVCS5cI20VAGYxC7M4IIrI8v6xkF7I0E8cxan2 IY04v7MxkF7I0En4kS14v26r1q6r43MxAIw28IcxkI7VAKI48JMxC20s026xCaFVCjc4AY 6r1j6r4UMI8I3I0E5I8CrVAFwI0_Jr0_Jr4lx2IqxVCjr7xvwVAFwI0_JrI_JrWlx4CE17 CEb7AF67AKxVWUtVW8ZwCIc40Y0x0EwIxGrwCI42IY6xIIjxv20xvE14v26r1j6r1xMIIF 0xvE2Ix0cI8IcVCY1x0267AKxVW8JVWxJwCI42IY6xAIw20EY4v20xvaj40_Jr0_JF4lIx AIcVC2z280aVAFwI0_Jr0_Gr1lIxAIcVC2z280aVCY1x0267AKxVW8JVW8JrUvcSsGvfC2 KfnxnUUI43ZEXa7VUjrHUDUUUUU== X-CM-SenderInfo: pzdqw2pxlnt03j6l2u1dvotugofq/ Use __riscv_has_extension_unlikely() to check for RISCV_ISA_EXT_SVVPTC, replacing the use of asm goto with ALTERNATIVE. The "unlikely" variant is used to match the behavior of the original implementation using ALTERNATIVE("nop", "j %l[svvptc]", ...). Signed-off-by: Vivian Wang --- arch/riscv/include/asm/pgtable.h | 15 +++++++-------- arch/riscv/mm/pgtable.c | 22 ++++++++++------------ 2 files changed, 17 insertions(+), 20 deletions(-) diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgta= ble.h index 29e994a9afb67c638173d4a2475fdfbd91bee967..02f37322eb83a113b411e95e153= fecc5c20319ad 100644 --- a/arch/riscv/include/asm/pgtable.h +++ b/arch/riscv/include/asm/pgtable.h @@ -496,8 +496,13 @@ static inline void update_mmu_cache_range(struct vm_fa= ult *vmf, struct vm_area_struct *vma, unsigned long address, pte_t *ptep, unsigned int nr) { - asm goto(ALTERNATIVE("nop", "j %l[svvptc]", 0, RISCV_ISA_EXT_SVVPTC, 1) - : : : : svvptc); + /* + * Svvptc guarantees that the new valid pte will be visible within + * a bounded timeframe, so when the uarch does not cache invalid + * entries, we don't have to do anything. + */ + if (__riscv_has_extension_unlikely(0, RISCV_ISA_EXT_SVVPTC)) + return; =20 /* * The kernel assumes that TLBs don't cache invalid entries, but @@ -509,12 +514,6 @@ static inline void update_mmu_cache_range(struct vm_fa= ult *vmf, while (nr--) local_flush_tlb_page(address + nr * PAGE_SIZE); =20 -svvptc:; - /* - * Svvptc guarantees that the new valid pte will be visible within - * a bounded timeframe, so when the uarch does not cache invalid - * entries, we don't have to do anything. - */ } #define update_mmu_cache(vma, addr, ptep) \ update_mmu_cache_range(NULL, vma, addr, ptep, 1) diff --git a/arch/riscv/mm/pgtable.c b/arch/riscv/mm/pgtable.c index 8b6c0a112a8db4e91de54c3bd3bd527a605a6197..289ca6fa6b4de80d42287d28e26= 6a0a8d3848cff 100644 --- a/arch/riscv/mm/pgtable.c +++ b/arch/riscv/mm/pgtable.c @@ -9,8 +9,16 @@ int ptep_set_access_flags(struct vm_area_struct *vma, unsigned long address, pte_t *ptep, pte_t entry, int dirty) { - asm goto(ALTERNATIVE("nop", "j %l[svvptc]", 0, RISCV_ISA_EXT_SVVPTC, 1) - : : : : svvptc); + if (__riscv_has_extension_unlikely(0, RISCV_ISA_EXT_SVVPTC)) { + if (!pte_same(ptep_get(ptep), entry)) { + __set_pte_at(vma->vm_mm, ptep, entry); + /* Here only not svadu is impacted */ + flush_tlb_page(vma, address); + return true; + } + + return false; + } =20 if (!pte_same(ptep_get(ptep), entry)) __set_pte_at(vma->vm_mm, ptep, entry); @@ -19,16 +27,6 @@ int ptep_set_access_flags(struct vm_area_struct *vma, * the case that the PTE changed and the spurious fault case. */ return true; - -svvptc: - if (!pte_same(ptep_get(ptep), entry)) { - __set_pte_at(vma->vm_mm, ptep, entry); - /* Here only not svadu is impacted */ - flush_tlb_page(vma, address); - return true; - } - - return false; } =20 int ptep_test_and_clear_young(struct vm_area_struct *vma, --=20 2.50.1