From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0A72DC87FCB for ; Wed, 30 Jul 2025 17:56:59 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 90CDF6B0088; Wed, 30 Jul 2025 13:56:59 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 8BBD96B0089; Wed, 30 Jul 2025 13:56:59 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 7D1B16B008A; Wed, 30 Jul 2025 13:56:59 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id 6C1F46B0088 for ; Wed, 30 Jul 2025 13:56:59 -0400 (EDT) Received: from smtpin22.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id E8DDC1345D4 for ; Wed, 30 Jul 2025 17:56:58 +0000 (UTC) X-FDA: 83721686916.22.D3BD093 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf18.hostedemail.com (Postfix) with ESMTP id 5133C1C000B for ; Wed, 30 Jul 2025 17:56:57 +0000 (UTC) Authentication-Results: imf18.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=FmhIB6rw; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf18.hostedemail.com: domain of sj@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=sj@kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1753898217; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=dYgfJDyz2xwIXG5cQAozKpj0KEiIL+nHO0Hr7irD6zc=; b=IedunSWrRV4UdZh1Ax9jLPgcsFAhaCnmJZvJri6JDu/Te8BBJjb7VCDI34pDScHn2VcOxs xLe8h9li588N2rqoUnScB694VmGRNX2R+rZgYLKpYndX5NkAeaDrkafxNQlMO9tTDT93k6 RyoU7md+Iuw3zu3WdLUaRyEs4AUuwFo= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1753898217; a=rsa-sha256; cv=none; b=48tEYR0bSKnP115aAZcCRUA8gO/Kd5dvGpas9qoZpH93c24Nvd5J3QIXlO56m1eiIK3Yrs PsDi/Hmcl69kWxEyzPF0z2ls+D9udeIAPQanltphd8DqDUdVNrgHZA66DPagOB4Uww2puW GINTV2SsHIQxvmW8UiczXNYvfFo23L0= ARC-Authentication-Results: i=1; imf18.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=FmhIB6rw; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf18.hostedemail.com: domain of sj@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=sj@kernel.org Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id 2BC865C2609; Wed, 30 Jul 2025 17:56:56 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A1176C4CEE7; Wed, 30 Jul 2025 17:56:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1753898215; bh=LxlL3e6vR/HG4aAeNYWdTWRtYhjSKsDeB3n9zodRNKc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=FmhIB6rwEPaQO/Kz2XplzMkph3aNpT/mO8O9r3oM07r1u2d/KSkOmLDTwvIIVGs+9 qrS9w9JcKtrEzhSH1eZVWTCgNdV9WqCbiFnGSf7fpfPJ9a1uXtQg2rnucfQbXyH7vt YpWeppA9eHbXki8P8Kpsuduy5rbUCSW7J3KH6wJ2gIXeNhmmVgjlC+aUguWjnEBVpI Kw5w8z0hcK/sfavGU6AsLX39TbLvXrJ+6c0x9xv3m/kukaKKBgFDqbSLuU1VS9paIp Mv37T8M6Bslm1zXa+gB5/ar0I71926sLzi6DcZRFjDj3mqUvRiMt2PyTVVnlwai9uj aqDRnYn18lDrQ== From: SeongJae Park To: Yueyang Pan Cc: SeongJae Park , Andrew Morton , Usama Arif , damon@lists.linux.dev, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 2/2] mm/damon: Add damos_stat support for vaddr Date: Wed, 30 Jul 2025 10:56:52 -0700 Message-Id: <20250730175652.60173-1-sj@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Rspamd-Queue-Id: 5133C1C000B X-Stat-Signature: 8bst39kwia3xkhnrt7p9p79ppdpihg7b X-Rspam-User: X-Rspamd-Server: rspam11 X-HE-Tag: 1753898217-327498 X-HE-Meta: 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 ad9AQxY+ YhH7OBdR0R8Kq+7ze3qAr3ZL6cDSIpm06TuRaKY66d1UR8J77HFCybmeHtN4vw7qeYvfmp33OPCgKspwmVfD2U2LUxHvsghlO7U3LlLG/2wh6c8epGxw9/iovefbB8LHomtMGlKc5J66dlhLsbVYJ2FxAMbqc/Lykiqag3952B6/OiKYasnYR9tgCmYzWQefOpX0zsvLOVGq7OaluR6E1DmeYzUgH9tkziQ73TH/8CJoNHOFsfnPG3R8Du4IURDRgO1edoAsXLKzoqeOOshphtfhiIYvfYv1yHgM9ZN32N/5XD2UX320mYOOx/g== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, 30 Jul 2025 10:19:56 -0700 Yueyang Pan wrote: > This patch adds support for damos_stat in virtual address space. > It leverages the walk_page_range to walk the page table and gets > the folio from page table. The last folio scanned is stored in > damos->last_applied to prevent double counting. > > Signed-off-by: Yueyang Pan > --- > mm/damon/vaddr.c | 105 ++++++++++++++++++++++++++++++++++++++++++++++- > 1 file changed, 104 insertions(+), 1 deletion(-) > > diff --git a/mm/damon/vaddr.c b/mm/damon/vaddr.c > index 87e825349bdf..6ed919e817e2 100644 > --- a/mm/damon/vaddr.c > +++ b/mm/damon/vaddr.c > @@ -890,6 +890,109 @@ static unsigned long damos_va_migrate(struct damon_target *target, > return applied * PAGE_SIZE; > } > > +struct damos_va_stat_private { > + struct damos *scheme; > + unsigned long *sz_filter_passed; > +}; > + > +static inline bool damon_va_invalid_damos_folio(struct folio *folio, struct damos *s) Weirdly DAMON code usually keeps the 80 columns limit. Could you please break down this line? Also, the name feels long to me. What about damos_va_invalid_folio()? > +{ > + return !folio || folio == s->last_applied; > +} > + > +static int damos_va_stat_pmd_entry(pmd_t *pmd, unsigned long addr, > + unsigned long next, struct mm_walk *walk) > +{ > + struct damos_va_stat_private *priv = walk->private; > + struct damos *s = priv->scheme; > + unsigned long *sz_filter_passed = priv->sz_filter_passed; > + struct vm_area_struct *vma = walk->vma; > + struct folio *folio; > + spinlock_t *ptl; > + pte_t *start_pte, *pte, ptent; > + int nr; > + > +#ifdef CONFIG_TRANSPARENT_HUGEPAGE > + if (pmd_trans_huge(*pmd)) { > + pmd_t pmde; > + > + ptl = pmd_trans_huge_lock(pmd, vma); > + if (!ptl) > + return 0; > + pmde = pmdp_get(pmd); > + if (!pmd_present(pmde)) > + goto huge_unlock; > + > + folio = vm_normal_folio_pmd(vma, addr, pmde); > + > + if (damon_va_invalid_damos_folio(folio, s)) > + goto huge_unlock; > + > + if (!damos_va_filter_out(s, folio, vma, addr, NULL, pmd)) > + *sz_filter_passed += folio_size(folio); > + s->last_applied = folio; > + > +huge_unlock: > + spin_unlock(ptl); > + return 0; > + } > +#endif > + start_pte = pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); > + if (!start_pte) > + return 0; > + > + for (; addr < next; pte += nr, addr += nr * PAGE_SIZE) { > + nr = 1; > + ptent = ptep_get(pte); > + > + if (pte_none(ptent) || !pte_present(ptent)) > + continue; > + > + folio = vm_normal_folio(vma, addr, ptent); > + > + if (damon_va_invalid_damos_folio(folio, s)) > + continue; > + > + if (!damos_va_filter_out(s, folio, vma, addr, pte, NULL)) > + *sz_filter_passed += folio_size(folio); > + nr = folio_nr_pages(folio); > + s->last_applied = folio; > + } > + > + pte_unmap_unlock(start_pte, ptl); > + No strong opinion, but I'd like to drop above two blank lines (one after the for loop, and one after pte_unmap_unlock() if you don't mind. > + return 0; > +} > + > +static unsigned long damos_va_stat(struct damon_target *target, > + struct damon_region *r, struct damos *s, > + unsigned long *sz_filter_passed) > +{ > + Seems this is unnecessary blank line. Let's remove it. > + struct damos_va_stat_private priv; > + struct mm_struct *mm; > + struct mm_walk_ops walk_ops = { > + .pmd_entry = damos_va_stat_pmd_entry, > + .walk_lock = PGWALK_RDLOCK, > + }; > + > + priv.scheme = s; > + priv.sz_filter_passed = sz_filter_passed; > + > + if (!damon_scheme_has_filter(s)) > + return 0; > + > + mm = damon_get_mm(target); > + if (!mm) > + return 0; > + > + mmap_read_lock(mm); > + walk_page_range(mm, r->ar.start, r->ar.end, &walk_ops, &priv); > + mmap_read_unlock(mm); > + mmput(mm); > + return 0; > +} > + > static unsigned long damon_va_apply_scheme(struct damon_ctx *ctx, > struct damon_target *t, struct damon_region *r, > struct damos *scheme, unsigned long *sz_filter_passed) > @@ -916,7 +1019,7 @@ static unsigned long damon_va_apply_scheme(struct damon_ctx *ctx, > case DAMOS_MIGRATE_COLD: > return damos_va_migrate(t, r, scheme, sz_filter_passed); > case DAMOS_STAT: > - return 0; > + return damos_va_stat(t, r, scheme, sz_filter_passed); > default: > /* > * DAMOS actions that are not yet supported by 'vaddr'. > -- > 2.47.3 Thanks, SJ