From nobody Sun Dec 14 19:13:39 2025 Received: from invmail4.hynix.com (exvmail4.skhynix.com [166.125.252.92]) by smtp.subspace.kernel.org (Postfix) with ESMTP id DA38F1E571A for ; Thu, 20 Feb 2025 05:36:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=166.125.252.92 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740029767; cv=none; b=uf8U7ZHEF7x41ouh8wZN4JnTEOO0zgbxyXiGXfiXhnxwYBxo5ETPWQIbEUFZ8Z1RRl4pCma/axPhP7BhFxAZwD8+puT3BQCqw096XpJwCVs5ha5kDu3DdLLpOGP2wj8AF9Vqz0Y8kRRZ9jbWtY8uI5TerSiH5H1VBfWp3hPefuU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740029767; c=relaxed/simple; bh=w7vX7JgcAEQHAdfHnEtOdFTLy8UIyanj3an2oyK8r3E=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References; b=u2mDYE2Idu+9rG+2fX6xnLHH/k4sQGdqM39QrwITPOI8aOVCk9O35fbu8t5Mc6NOXKADPGEZHDLv/MY+/fOHGGZJJ4+r3OBldV9a4yvuDS2OX7tUahoN7p5videhZB9JqUqIF4apHozKht1G84qZPFXe6fhXF7V1k4Dqcb9O010= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=sk.com; spf=pass smtp.mailfrom=sk.com; arc=none smtp.client-ip=166.125.252.92 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=sk.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=sk.com X-AuditID: a67dfc5b-3c9ff7000001d7ae-f4-67b6bba6ccf4 From: Byungchul Park To: linux-kernel@vger.kernel.org, linux-mm@kvack.org Cc: kernel_team@skhynix.com, akpm@linux-foundation.org, ying.huang@intel.com, vernhao@tencent.com, mgorman@techsingularity.net, hughd@google.com, willy@infradead.org, david@redhat.com, peterz@infradead.org, luto@kernel.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, rjgolo@gmail.com Subject: [RFC PATCH v12 14/26] mm/rmap: recognize read-only tlb entries during batched tlb flush Date: Thu, 20 Feb 2025 14:20:15 +0900 Message-Id: <20250220052027.58847-15-byungchul@sk.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20250220052027.58847-1-byungchul@sk.com> References: <20250220052027.58847-1-byungchul@sk.com> X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFnrMLMWRmVeSWpSXmKPExsXC9ZZnoe6y3dvSDU5cMLeYs34Nm8XnDf/Y LF5saGe0+Lr+F7PF0099LBaXd81hs7i35j+rxflda1ktdizdx2Rx6cACJovjvQeYLObf+8xm sXnTVGaL41OmMlr8/gFUfHLWZBYHAY/vrX0sHjtn3WX3WLCp1GPzCi2PxXteMnlsWtXJ5rHp 0yR2j3fnzrF7nJjxm8Vj3slAj/f7rrJ5bP1l59E49Rqbx+dNcgF8UVw2Kak5mWWpRfp2CVwZ P/ZsZC04KVbxpHUrWwPjC6EuRk4OCQETiTWT2lm6GDnA7Edz+UHCbALqEjdu/GQGsUUEzCQO tv5hB7GZBe4ySRzoZwOxhQUSJNY2P2ABsVkEVCVmNhxlAhnDC1Tf2F0OMV1eYvWGA2BjOIHC P2b0grUKCZhKvFtwiQmi5jObxLsd6hC2pMTBFTdYJjDyLmBkWMUolJlXlpuYmWOil1GZl1mh l5yfu4kRGPTLav9E72D8dCH4EKMAB6MSD++M1m3pQqyJZcWVuYcYJTiYlUR42+q3pAvxpiRW VqUW5ccXleakFh9ilOZgURLnNfpWniIkkJ5YkpqdmlqQWgSTZeLglGpgzPlhdov7meX1hzlX j7eIndjz/NQBa59mlz2uVx+zeyfJPbG9bXpQ8VRw2ZXGgvtii24+77AN+bCo4f5XlfMW2Qpd sTHCd12Xl3qedX6+9tHaANZ3J3P2b9kfq9y7fnF27vt/YicuWS++OH+fDue9uBARCfZn2Xyt Z5PY32m5H6j7d9y4sdP7oBJLcUaioRZzUXEiAFB+uU92AgAA X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFjrNLMWRmVeSWpSXmKPExsXC5WfdrLts97Z0g5U3dS3mrF/DZvF5wz82 ixcb2hktvq7/xWzx9FMfi8XhuSdZLS7vmsNmcW/Nf1aL87vWslrsWLqPyeLSgQVMFsd7DzBZ zL/3mc1i86apzBbHp0xltPj9A6j45KzJLA6CHt9b+1g8ds66y+6xYFOpx+YVWh6L97xk8ti0 qpPNY9OnSewe786dY/c4MeM3i8e8k4Ee7/ddZfNY/OIDk8fWX3YejVOvsXl83iQXwB/FZZOS mpNZllqkb5fAlfFjz0bWgpNiFU9at7I1ML4Q6mLk4JAQMJF4NJe/i5GTg01AXeLGjZ/MILaI gJnEwdY/7CA2s8BdJokD/WwgtrBAgsTa5gcsIDaLgKrEzIajTCBjeIHqG7vLQcISAvISqzcc ABvDCRT+MaMXrFVIwFTi3YJLTBMYuRYwMqxiFMnMK8tNzMwx1SvOzqjMy6zQS87P3cQIDOJl tX8m7mD8ctn9EKMAB6MSD++Dx1vThVgTy4orcw8xSnAwK4nwttVvSRfiTUmsrEotyo8vKs1J LT7EKM3BoiTO6xWemiAkkJ5YkpqdmlqQWgSTZeLglGpg1LkjXdLXPGX5tN8CbH3Hpggxr9z6 XeOBpoS47P71YiuMjF//X65ldlPM2+rrMxEra3+WyZtTLmvcXpXWtGzPutn/fPUZ9mw8oMv1 3IG35IPY3ir749UaZ8NX8e1y0L7XekdBTFT7wWFOkcctobuPzZqjGW33yzFLR69jhVfiQvXp y7YJHNrkpsRSnJFoqMVcVJwIALEjBHJeAgAA X-CFilter-Loop: Reflected Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Functionally, no change. This is a preparation for luf mechanism that requires to recognize read-only tlb entries and handle them in a different way. The newly introduced API in this patch, fold_ubc(), will be used by luf mechanism. Signed-off-by: Byungchul Park --- include/linux/sched.h | 1 + mm/rmap.c | 16 ++++++++++++++-- 2 files changed, 15 insertions(+), 2 deletions(-) diff --git a/include/linux/sched.h b/include/linux/sched.h index c4ff83e1d5953..a217d6011fdfe 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1381,6 +1381,7 @@ struct task_struct { =20 struct tlbflush_unmap_batch tlb_ubc; struct tlbflush_unmap_batch tlb_ubc_takeoff; + struct tlbflush_unmap_batch tlb_ubc_ro; =20 /* Cache last used pipe for splice(): */ struct pipe_inode_info *splice_pipe; diff --git a/mm/rmap.c b/mm/rmap.c index 1581b1a00f974..3ed6234dd777e 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -775,6 +775,7 @@ void fold_luf_batch(struct luf_batch *dst, struct luf_b= atch *src) void try_to_unmap_flush_takeoff(void) { struct tlbflush_unmap_batch *tlb_ubc =3D ¤t->tlb_ubc; + struct tlbflush_unmap_batch *tlb_ubc_ro =3D ¤t->tlb_ubc_ro; struct tlbflush_unmap_batch *tlb_ubc_takeoff =3D ¤t->tlb_ubc_takeof= f; =20 if (!tlb_ubc_takeoff->flush_required) @@ -789,6 +790,9 @@ void try_to_unmap_flush_takeoff(void) if (arch_tlbbatch_done(&tlb_ubc->arch, &tlb_ubc_takeoff->arch)) reset_batch(tlb_ubc); =20 + if (arch_tlbbatch_done(&tlb_ubc_ro->arch, &tlb_ubc_takeoff->arch)) + reset_batch(tlb_ubc_ro); + reset_batch(tlb_ubc_takeoff); } =20 @@ -801,7 +805,9 @@ void try_to_unmap_flush_takeoff(void) void try_to_unmap_flush(void) { struct tlbflush_unmap_batch *tlb_ubc =3D ¤t->tlb_ubc; + struct tlbflush_unmap_batch *tlb_ubc_ro =3D ¤t->tlb_ubc_ro; =20 + fold_batch(tlb_ubc, tlb_ubc_ro, true); if (!tlb_ubc->flush_required) return; =20 @@ -813,8 +819,9 @@ void try_to_unmap_flush(void) void try_to_unmap_flush_dirty(void) { struct tlbflush_unmap_batch *tlb_ubc =3D ¤t->tlb_ubc; + struct tlbflush_unmap_batch *tlb_ubc_ro =3D ¤t->tlb_ubc_ro; =20 - if (tlb_ubc->writable) + if (tlb_ubc->writable || tlb_ubc_ro->writable) try_to_unmap_flush(); } =20 @@ -831,13 +838,18 @@ void try_to_unmap_flush_dirty(void) static void set_tlb_ubc_flush_pending(struct mm_struct *mm, pte_t pteval, unsigned long uaddr) { - struct tlbflush_unmap_batch *tlb_ubc =3D ¤t->tlb_ubc; + struct tlbflush_unmap_batch *tlb_ubc; int batch; bool writable =3D pte_dirty(pteval); =20 if (!pte_accessible(mm, pteval)) return; =20 + if (pte_write(pteval)) + tlb_ubc =3D ¤t->tlb_ubc; + else + tlb_ubc =3D ¤t->tlb_ubc_ro; + arch_tlbbatch_add_pending(&tlb_ubc->arch, mm, uaddr); tlb_ubc->flush_required =3D true; =20 --=20 2.17.1