From nobody Sun Dec 14 19:12:54 2025 Received: from invmail4.hynix.com (exvmail4.skhynix.com [166.125.252.92]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 5CD6515FA73 for ; Fri, 10 May 2024 06:52:32 +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=1715323954; cv=none; b=D10KLdUjRXORWqBhiF3nqCkTzmgYH1kpQPKseKCWAytw2nh88PB22Xh9Lmzyzz1Wjf1YvReQlXQa4GYdpefimk1AFkKflKS0nkL7JBrLLWfIvLNIG+UiNHYLhq8XkLck/j71fC8xORu1ylyAH1MN2yqtKfOOWlxgUndvx2uETt0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715323954; c=relaxed/simple; bh=F8iBaXPfyAs8+pBArnftJrFJRE6eOJaC+K3wXJHYEbY=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References; b=jJ7nzcsgbXlxcv2eNmatGzM9bNZP/DUBPrypD+ku4Tw6lpSZ2Vt9FVsKryyjVGl/yDomHp7v44q3L1wYP6dP/LCiERJuGu98kuinUA9GpziIFgWL+bEMnBUdNfTi6rHBHHW55th4/y7WWXNcVnjb2f8ScWl8sOpD0li3RU/pbgA= 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-d6dff70000001748-e7-663dc421aa7f 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: [PATCH v10 08/12] mm/rmap: recognize read-only tlb entries during batched tlb flush Date: Fri, 10 May 2024 15:52:02 +0900 Message-Id: <20240510065206.76078-9-byungchul@sk.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20240510065206.76078-1-byungchul@sk.com> References: <20240510065206.76078-1-byungchul@sk.com> X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFnrKLMWRmVeSWpSXmKPExsXC9ZZnoa7iEds0g4MTtSzmrF/DZvF5wz82 ixcb2hktvq7/xWzx9FMfi8XlXXPYLO6t+c9qcX7XWlaLHUv3MVlcOrCAyeJ47wEmi/n3PrNZ bN40ldni+JSpjBa/fwAVn5w1mcVBwON7ax+Lx85Zd9k9Fmwq9di8Qstj8Z6XTB6bVnWyeWz6 NInd4925c+weJ2b8ZvGYdzLQ4/2+q2weW3/ZeTROvcbm8XmTXABfFJdNSmpOZllqkb5dAldG w7tH7AV3ZCsu7p7B1sB4RKKLkZNDQsBE4u/ucyww9vU3G5hBbDYBdYkbN36C2SICZhIHW/+w g9jMAneZJA70s3UxcnAIC8RINCyyAQmzCKhKXD19kg3E5hUwldhw/QATxEh5idUbDoCN4QQa 82HZDLC4EFBNx4OJjF2MXEA1n9kk3vZPY4ZokJQ4uOIGywRG3gWMDKsYhTLzynITM3NM9DIq 8zIr9JLzczcxAgN/We2f6B2Mny4EH2IU4GBU4uHdsdkmTYg1say4MvcQowQHs5IIb1WNdZoQ b0piZVVqUX58UWlOavEhRmkOFiVxXqNv5SlCAumJJanZqakFqUUwWSYOTqkGxpDXRTu2PZZ/ Y+T9YXruc02NV6vONXfnaXVHOd4UbpguYpJR3xsm2MPL4XlC+aNP4VvD9F3ma/wETkzvWsR6 6RvXYYeX3O1/+3TW6tTquxYWLmwo74yv9Mtp6rdzTEwukSx/nV9V73XSPVGkdBPz2f6PDd4s Loed1ir+5k1i1mztUKza+l6JpTgj0VCLuag4EQBNYvAHeAIAAA== X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFjrDLMWRmVeSWpSXmKPExsXC5WfdrKt4xDbNYNUHBYs569ewWXze8I/N 4sWGdkaLr+t/MVs8/dTHYnF47klWi8u75rBZ3Fvzn9Xi/K61rBY7lu5jsrh0YAGTxfHeA0wW 8+99ZrPYvGkqs8XxKVMZLX7/ACo+OWsyi4Ogx/fWPhaPnbPusnss2FTqsXmFlsfiPS+ZPDat 6mTz2PRpErvHu3Pn2D1OzPjN4jHvZKDH+31X2TwWv/jA5LH1l51H49RrbB6fN8kF8Edx2aSk 5mSWpRbp2yVwZTS8e8RecEe24uLuGWwNjEckuhg5OSQETCSuv9nADGKzCahL3LjxE8wWETCT ONj6hx3EZha4yyRxoJ+ti5GDQ1ggRqJhkQ1ImEVAVeLq6ZNsIDavgKnEhusHmCBGykus3nAA bAwn0JgPy2aAxYWAajoeTGScwMi1gJFhFaNIZl5ZbmJmjqlecXZGZV5mhV5yfu4mRmAYL6v9 M3EH45fL7ocYBTgYlXh4d2y2SRNiTSwrrsw9xCjBwawkwltVY50mxJuSWFmVWpQfX1Sak1p8 iFGag0VJnNcrPDVBSCA9sSQ1OzW1ILUIJsvEwSnVwOjyVOdO4urdb9Y9eTd7wWrpJXo2rY0a GUlbY+YZsrA07VppI2Qtk//9542Sg04fKvsKeyK8S28vnXqxN/nXhD2Kgl9DWG7d0JENNjzc l65yz+fbCbt3YYHLyquu98y13cCxfmpJWq+uaL/tZb5//W/7TzAcWv3g+XEGSwkbEzsPlruX Qqd/l1FiKc5INNRiLipOBADOpyuuXwIAAA== 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/internal.h | 4 ++++ mm/rmap.c | 34 ++++++++++++++++++++++++++++++++-- 3 files changed, 37 insertions(+), 2 deletions(-) diff --git a/include/linux/sched.h b/include/linux/sched.h index 2aa48adad226..0915390b1b5e 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1339,6 +1339,7 @@ struct task_struct { #endif =20 struct tlbflush_unmap_batch tlb_ubc; + struct tlbflush_unmap_batch tlb_ubc_ro; unsigned short int ugen; =20 /* Cache last used pipe for splice(): */ diff --git a/mm/internal.h b/mm/internal.h index 0d4c74e76de6..805f0e6ecab4 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -1100,6 +1100,7 @@ extern struct workqueue_struct *mm_percpu_wq; void try_to_unmap_flush(void); void try_to_unmap_flush_dirty(void); void flush_tlb_batched_pending(struct mm_struct *mm); +void fold_ubc(struct tlbflush_unmap_batch *dst, struct tlbflush_unmap_batc= h *src); #else static inline void try_to_unmap_flush(void) { @@ -1110,6 +1111,9 @@ static inline void try_to_unmap_flush_dirty(void) static inline void flush_tlb_batched_pending(struct mm_struct *mm) { } +static inline void fold_ubc(struct tlbflush_unmap_batch *dst, struct tlbfl= ush_unmap_batch *src) +{ +} #endif /* CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH */ =20 extern const struct trace_print_flags pageflag_names[]; diff --git a/mm/rmap.c b/mm/rmap.c index cf8a99a49aef..328b5e2217e6 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -635,6 +635,28 @@ struct anon_vma *folio_lock_anon_vma_read(struct folio= *folio, } =20 #ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH + +void fold_ubc(struct tlbflush_unmap_batch *dst, + struct tlbflush_unmap_batch *src) +{ + if (!src->flush_required) + return; + + /* + * Fold src to dst. + */ + arch_tlbbatch_fold(&dst->arch, &src->arch); + dst->writable =3D dst->writable || src->writable; + dst->flush_required =3D true; + + /* + * Reset src. + */ + arch_tlbbatch_clear(&src->arch); + src->flush_required =3D false; + src->writable =3D false; +} + /* * Flush TLB entries for recently unmapped pages from remote CPUs. It is * important if a PTE was dirty when it was unmapped that it's flushed @@ -644,7 +666,9 @@ struct anon_vma *folio_lock_anon_vma_read(struct folio = *folio, 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_ubc(tlb_ubc, tlb_ubc_ro); if (!tlb_ubc->flush_required) return; =20 @@ -658,8 +682,9 @@ 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 @@ -676,13 +701,18 @@ 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