From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 9652E3A451B; Sat, 5 Sep 2026 20:26:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788640005; cv=none; b=krDMD7vj65BVEg/l4lIQC47Jk/kZvHx+7MsQTv4bCjXv3JQO4s2KVldFUfWzlpot+4mf2k4xBb/V8IgWuzNrNxuRZz4D4JHVp7IaluWVu/5QgFcwIn6cO6hVRpb+KI76ZREJw00YNuO/w5PK3TZnX5FhkboDAHjzPlMrxGPcHSc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788640005; c=relaxed/simple; bh=E7fgarhF93UmeFS3xcsx89VbQHqmZiIyVfzBU35jzC4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=IGALPuv5uIct0daJiCpdTctOFTGTVHGhde+k5xlukTYGFRMoBo2mmKfodfPXrP3IV/6f+46qSiEycm6UQF+3Gy56EGyLMhI8yxr/wuXIc2BoVDPWdWsKmt7XURwGLjLzmwfpbbm4Y4ybHkyySKB4va0O8aq4ZyCteWjRCK0wlog= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=bPeXXfgN; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="bPeXXfgN" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 499021F00A3F; Sat, 5 Sep 2026 20:26:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788640004; bh=fT43lELJTSuTapSRQfge6uMBnWbBQLknesZmv7ILLgU=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=bPeXXfgNTpyOh45yiXs2EzQRjiiM6Wt1vHoDx5xyU3NeX364Av3sKdvtQDCbe8qHy pVrw5uyfZslrQTGnMJJasukhfK/kewkIoknKBdkSBLEMhTE9E4ODOSrnzrX7rpzEHo QgtK8vLfNpLpe5syT0GsPjo7G0199vs3no+yzWpZumPhCEurk7s4LvdJHsWnnGVqLT C2hzhdWIKS34Trmn5Csy6ojjaWxau7D/uI5UBRj0PFR+iqBmedA24zakW5HI3Fg1tO jaxK70+w3xpBepaL+SqxW0AOB+SfZL9rulaq3Pese1xLqJGD8V5QVyh2D88yvSB1ez fbk0FOHkW2E0A== From: SJ Park To: Cc: SJ Park , Andrew Morton , damon@lists.linux.dev, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [RFC PATCH 3/5] mm/damon/vaddr: support apply_probe Date: Sat, 5 Sep 2026 13:26:25 -0700 Message-ID: <20260905202634.88102-4-sj@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260905202634.88102-1-sj@kernel.org> References: <20260905202634.88102-1-sj@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit DAMON virtual address space operation set (vaddr) is not supporting apply_probe. Add a minimum support. Do not support hugetlb pages and PGIDLE_UNSET filter type for simplicity. Signed-off-by: SJ Park --- mm/damon/vaddr.c | 123 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 123 insertions(+) diff --git a/mm/damon/vaddr.c b/mm/damon/vaddr.c index 20f4784f17817..7c548ec0cf6b5 100644 --- a/mm/damon/vaddr.c +++ b/mm/damon/vaddr.c @@ -522,6 +522,128 @@ static void damon_va_prep_probes(struct damon_ctx *ctx, bool set_samples) } } +static bool damon_va_filter_pass(struct folio *folio, struct damon_probe *p) +{ + struct damon_filter *f; + bool pass = true; + + damon_for_each_filter(f, p) { + if (damon_ops_filter_match(f, folio)) { + pass = f->allow; + break; + } + pass = !f->allow; + } + return pass; +} + +struct damon_va_probe_walk_private { + struct damon_ctx *ctx; + struct damon_region *r; +}; + +static void damon_va_probe_folio(struct damon_ctx *ctx, + struct damon_region *r, struct folio *folio) +{ + struct damon_probe *probe; + int i = 0; + + damon_for_each_probe(probe, ctx) { + if (damon_va_filter_pass(folio, probe)) + r->probe_hits[i]++; + i++; + } +} + +static int damon_va_probe_pmd_entry(pmd_t *pmd, unsigned long addr, + unsigned long next, struct mm_walk *walk) +{ + pte_t *pte; + pte_t ptent; + spinlock_t *ptl; + struct folio *folio; + struct damon_va_probe_walk_private *priv = walk->private; + +#ifdef CONFIG_TRANSPARENT_HUGEPAGE + ptl = pmd_trans_huge_lock(pmd, walk->vma); + if (ptl) { + pmd_t pmde = pmdp_get(pmd); + + if (!pmd_present(pmde)) + goto huge_out; + folio = vm_normal_folio_pmd(walk->vma, addr, pmde); + if (!folio) + goto huge_out; + damon_va_probe_folio(priv->ctx, priv->r, folio); + +huge_out: + spin_unlock(ptl); + return 0; + } +#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ + + pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl); + if (!pte) + return 0; + ptent = ptep_get(pte); + if (!pte_present(ptent)) + goto out; + folio = vm_normal_folio(walk->vma, addr, ptent); + if (!folio) + goto out; + damon_va_probe_folio(priv->ctx, priv->r, folio); + +out: + pte_unmap_unlock(pte, ptl); + return 0; +} + +static void __damon_va_apply_probes(struct damon_ctx *ctx, + struct mm_struct *mm, struct damon_region *r) +{ + struct damon_va_probe_walk_private arg = { + .ctx = ctx, + .r = r, + }; + struct mm_walk_ops damon_probe_walk_ops = { + .pmd_entry = damon_va_probe_pmd_entry, + .hugetlb_entry = NULL, + }; + unsigned long addr = r->sampling_addr; + + if (!mm) + return; + + damon_va_walk_page_range(mm, addr, addr + 1, &damon_probe_walk_ops, + &arg); +} + +static unsigned int damon_va_apply_probes(struct damon_ctx *ctx, + bool set_samples, bool return_max_wsum) +{ + struct damon_target *t; + struct mm_struct *mm; + struct damon_region *r; + unsigned int max_wsum = 0; + + damon_for_each_target(t, ctx) { + mm = damon_get_mm(t); + damon_for_each_region(r, t) { + if (set_samples) + r->sampling_addr = damon_rand(ctx, r->ar.start, + r->ar.end); + __damon_va_apply_probes(ctx, mm, r); + if (return_max_wsum) + max_wsum = max(damon_probe_hits_wsum(r, false, + ctx), max_wsum); + } + if (mm) + mmput(mm); + } + + return max_wsum; +} + static bool damos_va_filter_young_match(struct damos_filter *filter, struct folio *folio, struct vm_area_struct *vma, unsigned long addr, pte_t *ptep, pmd_t *pmdp) @@ -951,6 +1073,7 @@ static int __init damon_va_initcall(void) .prepare_access_checks = damon_va_prepare_access_checks, .check_accesses = damon_va_check_accesses, .prep_probes = damon_va_prep_probes, + .apply_probes = damon_va_apply_probes, .target_valid = damon_va_target_valid, .cleanup_target = damon_va_cleanup_target, .apply_scheme = damon_va_apply_scheme, -- 2.47.3