From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 45F9F1A238A for ; Mon, 12 May 2025 00:52:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747011142; cv=none; b=XmEIcVqBHPE/SQJqQMV83ExDkFPSwyirCEkTYcrk57mxNxUXfBHRSVdIFVN2o+sDt2L1O7+7eTlIMJr8svr/Xj2Qu1uvUVH931h/YTj8Aik5zo1MPLMOKUF0YwC+4T0zW+WB4QHRzk+pFqEs1h+V7u9u2SV+98peOWBvMzClTQ4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747011142; c=relaxed/simple; bh=+Yuva4eCBl2s/Ms7z19UB8RM6yVFXNxCcp9vr033AQ4=; h=Date:To:From:Subject:Message-Id; b=Bsuzp+2enXZg0QjTHCzekWmnKRj3ueMRlz2BtuLO/wwTiYiaiXs+LBWBNBv4k1pYb8VtbWApuSH/X5NgkCqEb3xJYb7LBJYytd5M4z5Nvo/wYOXiMrzqZklw3wQmZShDDnlWsKStueI+v3Nx+kP0BTN6iG9cO6eHCTK4fpgLEaE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=DK2hlpyu; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="DK2hlpyu" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1C9A7C4CEE4; Mon, 12 May 2025 00:52:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1747011142; bh=+Yuva4eCBl2s/Ms7z19UB8RM6yVFXNxCcp9vr033AQ4=; h=Date:To:From:Subject:From; b=DK2hlpyu8IXqgGjAP9rxbkLxbvzBBfkMfd6A7X8e8MSLG4dDMhUbSjl/T37VmIUD5 8QiKKaRZZx4bnGWOu7TD5HdRUbRZAdlAma9wQj1NcqMZVwl+av3juSQ3hVqD62hdon AbTjOnRRdNHjByItqX0/g0vQG4W53Sv3D9fma9og= Date: Sun, 11 May 2025 17:52:21 -0700 To: mm-commits@vger.kernel.org,ziy@nvidia.com,yang@os.amperecomputing.com,willy@infradead.org,vishal.moola@gmail.com,ryan.roberts@arm.com,hughd@google.com,david@redhat.com,baolin.wang@linux.alibaba.com,dev.jain@arm.com,akpm@linux-foundation.org From: Andrew Morton Subject: [merged mm-stable] mempolicy-optimize-queue_folios_pte_range-by-pte-batching.patch removed from -mm tree Message-Id: <20250512005222.1C9A7C4CEE4@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The quilt patch titled Subject: mempolicy: optimize queue_folios_pte_range by PTE batching has been removed from the -mm tree. Its filename was mempolicy-optimize-queue_folios_pte_range-by-pte-batching.patch This patch was dropped because it was merged into the mm-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: Dev Jain Subject: mempolicy: optimize queue_folios_pte_range by PTE batching Date: Wed, 16 Apr 2025 11:00:48 +0530 After the check for queue_folio_required(), the code only cares about the folio in the for loop, i.e the PTEs are redundant. Therefore, optimize this loop by skipping over a PTE batch mapping the same folio. With a test program migrating pages of the calling process, which includes a mapped VMA of size 4GB with pte-mapped large folios of order-9, and migrating once back and forth node-0 and node-1, the average execution time reduces from 7.5 to 4 seconds, giving an approx 47% speedup. Link: https://lkml.kernel.org/r/20250416053048.96479-1-dev.jain@arm.com Signed-off-by: Dev Jain Acked-by: David Hildenbrand Cc: Baolin Wang Cc: Hugh Dickins Cc: Matthew Wilcox (Oracle) Cc: Ryan Roberts Cc: Vishal Moola (Oracle) Cc: Yang Shi Cc: Zi Yan Signed-off-by: Andrew Morton --- mm/mempolicy.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) --- a/mm/mempolicy.c~mempolicy-optimize-queue_folios_pte_range-by-pte-batching +++ a/mm/mempolicy.c @@ -566,6 +566,7 @@ static void queue_folios_pmd(pmd_t *pmd, static int queue_folios_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, struct mm_walk *walk) { + const fpb_t fpb_flags = FPB_IGNORE_DIRTY | FPB_IGNORE_SOFT_DIRTY; struct vm_area_struct *vma = walk->vma; struct folio *folio; struct queue_pages *qp = walk->private; @@ -573,6 +574,7 @@ static int queue_folios_pte_range(pmd_t pte_t *pte, *mapped_pte; pte_t ptent; spinlock_t *ptl; + int max_nr, nr; ptl = pmd_trans_huge_lock(pmd, vma); if (ptl) { @@ -586,7 +588,9 @@ static int queue_folios_pte_range(pmd_t walk->action = ACTION_AGAIN; return 0; } - for (; addr != end; pte++, addr += PAGE_SIZE) { + for (; addr != end; pte += nr, addr += nr * PAGE_SIZE) { + max_nr = (end - addr) >> PAGE_SHIFT; + nr = 1; ptent = ptep_get(pte); if (pte_none(ptent)) continue; @@ -598,6 +602,10 @@ static int queue_folios_pte_range(pmd_t folio = vm_normal_folio(vma, addr, ptent); if (!folio || folio_is_zone_device(folio)) continue; + if (folio_test_large(folio) && max_nr != 1) + nr = folio_pte_batch(folio, addr, pte, ptent, + max_nr, fpb_flags, + NULL, NULL, NULL); /* * vm_normal_folio() filters out zero pages, but there might * still be reserved folios to skip, perhaps in a VDSO. @@ -630,7 +638,7 @@ static int queue_folios_pte_range(pmd_t if (!(flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) || !vma_migratable(vma) || !migrate_folio_add(folio, qp->pagelist, flags)) { - qp->nr_failed++; + qp->nr_failed += nr; if (strictly_unmovable(flags)) break; } _ Patches currently in -mm which might be from dev.jain@arm.com are