From nobody Tue Feb 10 20:05:59 2026 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.10]) (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 2624B824AF for ; Fri, 31 May 2024 08:13:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.10 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717143189; cv=none; b=qpcQdoBpfAOJ/UZFxy6VrX177Ttoj/PmmV0SQrr+zah0nxsPZY71GCK9YLSaTZLbO6hF+QeHhF1W5DaHY/zbHhbfMIaNxCVHUjIQABlOl7C4vr7u9+X9aiy4BDm133pkqKSDRyLdQdPVnLJgSguIH0jplFYkxbUheEqrRU61rlk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717143189; c=relaxed/simple; bh=XtM1tmkue2R/RWq0rdfSHuRCjgaKpNa2YNSgCs9L/sc=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=CTNmhWrcIZbADsljZdp37wqdipBJ0dVAF5K27uCicrZ/rS3zGKpyvMPVteEH718sOfOU2I+gjff+fxFlUYhXJaGSe0ILUkGBrD0/uXAPqNRXVNa4N2NbnLwQK7vIKMQSfMuVXZAciwZN6U1vjxeQE49xHpswsRGYRZJDskIQjoc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=R/9WTWu1; arc=none smtp.client-ip=192.198.163.10 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="R/9WTWu1" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1717143188; x=1748679188; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=XtM1tmkue2R/RWq0rdfSHuRCjgaKpNa2YNSgCs9L/sc=; b=R/9WTWu1EzTlAB+QM7FQOXTvjBF/ATXu2UeYXda6FNFHmRZqgTFHUCPR zW7LoPb/t+NvNXj6u6GLSKvDbIU5H7OARImkLd2pkNETaqwoPOxHMV7aQ FiDHDLcnD2483hjOIIMgiVqI4pMq5PelCMYCpezng6FFgd6I7teTnCN1H SSs0vTagduQT/m2BuElsEumNITmFLcGauHaBqZblqXj16HWCK9axbj7/O rIRmXU9wjuW7dALPP0aJ3OkabLmMXyZoRzRRVkuZUL8vb2y3Nf2vtMvO0 lka+9rGYMyFUoxrfY5wtqTMCDciPU5cDksD9PJphv9/dT3hFosM+AtAZS w==; X-CSE-ConnectionGUID: t0cJpyHcTo+Ho/wogisORg== X-CSE-MsgGUID: G5IZg+DBTRO5BL4aSNvR3w== X-IronPort-AV: E=McAfee;i="6600,9927,11088"; a="25079776" X-IronPort-AV: E=Sophos;i="6.08,203,1712646000"; d="scan'208";a="25079776" Received: from fmviesa002.fm.intel.com ([10.60.135.142]) by fmvoesa104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 31 May 2024 01:13:08 -0700 X-CSE-ConnectionGUID: ObA5obvcTXa5rgNCCMgFCQ== X-CSE-MsgGUID: rJElwWo5T9qLZMt+cdpi/g== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.08,203,1712646000"; d="scan'208";a="59270962" Received: from unknown (HELO yhuang6-mobl2.ccr.corp.intel.com) ([10.255.30.35]) by fmviesa002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 31 May 2024 01:13:04 -0700 From: Huang Ying To: Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Huang Ying , Hugh Dickins , Alistair Popple , Anshuman Khandual , David Hildenbrand , Mel Gorman , Miaohe Lin , Minchan Kim , Ryan Roberts , Yang Shi , Yu Zhao , Kairui Song , Barry Song , Chris Li , Yosry Ahmed Subject: [PATCH 3/3] mm,swap: simplify VMA based swap readahead window calculation Date: Fri, 31 May 2024 16:12:30 +0800 Message-Id: <20240531081230.310128-4-ying.huang@intel.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240531081230.310128-1-ying.huang@intel.com> References: <20240531081230.310128-1-ying.huang@intel.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Replace PFNs with addresses in readahead window calculation. This simplified the logic and reduce the code line number. No functionality change is expected. Signed-off-by: "Huang, Ying" Cc: Hugh Dickins Cc: Alistair Popple Cc: Anshuman Khandual Cc: David Hildenbrand Cc: Mel Gorman Cc: Miaohe Lin Cc: Minchan Kim Cc: Ryan Roberts Cc: Yang Shi Cc: Yu Zhao Cc: Kairui Song Cc: Barry Song Cc: Chris Li Cc: Yosry Ahmed --- mm/swap_state.c | 66 +++++++++++++++++++------------------------------ 1 file changed, 25 insertions(+), 41 deletions(-) diff --git a/mm/swap_state.c b/mm/swap_state.c index e1dac70198a6..d2adbd7b571b 100644 --- a/mm/swap_state.c +++ b/mm/swap_state.c @@ -740,54 +740,40 @@ void exit_swap_address_space(unsigned int type) swapper_spaces[type] =3D NULL; } =20 -static unsigned short swap_vma_ra_win(struct vm_fault *vmf, - unsigned short *offset, - unsigned short *nr_pte) +static int swap_vma_ra_win(struct vm_fault *vmf, unsigned long *start, + unsigned long *end) { struct vm_area_struct *vma =3D vmf->vma; unsigned long ra_val; - unsigned long faddr, pfn, fpfn, lpfn, rpfn; - unsigned long start, end; + unsigned long faddr, prev_faddr, left, right; unsigned int max_win, hits, prev_win, win; =20 - max_win =3D 1 << min_t(unsigned int, READ_ONCE(page_cluster), - SWAP_RA_ORDER_CEILING); + max_win =3D 1 << min(READ_ONCE(page_cluster), SWAP_RA_ORDER_CEILING); if (max_win =3D=3D 1) return 1; =20 faddr =3D vmf->address; - fpfn =3D PFN_DOWN(faddr); ra_val =3D GET_SWAP_RA_VAL(vma); - pfn =3D PFN_DOWN(SWAP_RA_ADDR(ra_val)); + prev_faddr =3D SWAP_RA_ADDR(ra_val); prev_win =3D SWAP_RA_WIN(ra_val); hits =3D SWAP_RA_HITS(ra_val); - win =3D __swapin_nr_pages(pfn, fpfn, hits, max_win, prev_win); - atomic_long_set(&vma->swap_readahead_info, - SWAP_RA_VAL(faddr, win, 0)); + win =3D __swapin_nr_pages(PFN_DOWN(prev_faddr), PFN_DOWN(faddr), hits, + max_win, prev_win); + atomic_long_set(&vma->swap_readahead_info, SWAP_RA_VAL(faddr, win, 0)); if (win =3D=3D 1) return 1; =20 - if (fpfn =3D=3D pfn + 1) { - lpfn =3D fpfn; - rpfn =3D fpfn + win; - } else if (pfn =3D=3D fpfn + 1) { - lpfn =3D fpfn - win + 1; - rpfn =3D fpfn + 1; - } else { - unsigned int left =3D (win - 1) / 2; - - lpfn =3D fpfn - left; - rpfn =3D fpfn + win - left; - } - if ((long)lpfn < 0) - lpfn =3D 0; - start =3D max3(lpfn, PFN_DOWN(vma->vm_start), - PFN_DOWN(faddr & PMD_MASK)); - end =3D min3(rpfn, PFN_DOWN(vma->vm_end), - PFN_DOWN((faddr & PMD_MASK) + PMD_SIZE)); - - *nr_pte =3D end - start; - *offset =3D fpfn - start; + if (faddr =3D=3D prev_faddr + PAGE_SIZE) + left =3D faddr; + else if (prev_faddr =3D=3D faddr + PAGE_SIZE) + left =3D faddr - (win << PAGE_SHIFT) + PAGE_SIZE; + else + left =3D faddr - (((win - 1) / 2) << PAGE_SHIFT); + right =3D left + (win << PAGE_SHIFT); + if ((long)left < 0) + left =3D 0; + *start =3D max3(left, vma->vm_start, faddr & PMD_MASK); + *end =3D min3(right, vma->vm_end, (faddr & PMD_MASK) + PMD_SIZE); =20 return win; } @@ -815,22 +801,20 @@ static struct folio *swap_vma_readahead(swp_entry_t t= arg_entry, gfp_t gfp_mask, struct swap_iocb *splug =3D NULL; struct folio *folio; pte_t *pte =3D NULL, pentry; - unsigned long addr; + int win; + unsigned long start, end, addr; swp_entry_t entry; pgoff_t ilx; - unsigned int i; bool page_allocated; - unsigned short win, nr_pte, offset; =20 - win =3D swap_vma_ra_win(vmf, &offset, &nr_pte); + win =3D swap_vma_ra_win(vmf, &start, &end); if (win =3D=3D 1) goto skip; =20 - addr =3D vmf->address - offset * PAGE_SIZE; - ilx =3D targ_ilx - offset; + ilx =3D targ_ilx - PFN_DOWN(vmf->address - start); =20 blk_start_plug(&plug); - for (i =3D 0; i < nr_pte; i++, ilx++, addr +=3D PAGE_SIZE) { + for (addr =3D start; addr < end; ilx++, addr +=3D PAGE_SIZE) { if (!pte++) { pte =3D pte_offset_map(vmf->pmd, addr); if (!pte) @@ -850,7 +834,7 @@ static struct folio *swap_vma_readahead(swp_entry_t tar= g_entry, gfp_t gfp_mask, continue; if (page_allocated) { swap_read_folio(folio, false, &splug); - if (i !=3D offset) { + if (addr !=3D vmf->address) { folio_set_readahead(folio); count_vm_event(SWAP_RA); } --=20 2.39.2