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 X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 22F91C43387 for ; Fri, 4 Jan 2019 02:25:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EB5CB2184B for ; Fri, 4 Jan 2019 02:25:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726433AbfADCZS (ORCPT ); Thu, 3 Jan 2019 21:25:18 -0500 Received: from mga06.intel.com ([134.134.136.31]:55071 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726036AbfADCZS (ORCPT ); Thu, 3 Jan 2019 21:25:18 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga104.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 03 Jan 2019 18:25:17 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.56,437,1539673200"; d="scan'208";a="135191315" Received: from yhuang-dev.sh.intel.com (HELO yhuang-dev) ([10.239.13.10]) by fmsmga001.fm.intel.com with ESMTP; 03 Jan 2019 18:25:15 -0800 From: "Huang\, Ying" To: Yang Shi Cc: , , , , , Subject: Re: [v5 PATCH 2/2] mm: swap: add comment for swap_vma_readahead References: <1546543673-108536-1-git-send-email-yang.shi@linux.alibaba.com> <1546543673-108536-2-git-send-email-yang.shi@linux.alibaba.com> Date: Fri, 04 Jan 2019 10:25:15 +0800 In-Reply-To: <1546543673-108536-2-git-send-email-yang.shi@linux.alibaba.com> (Yang Shi's message of "Fri, 4 Jan 2019 03:27:53 +0800") Message-ID: <87imz5tb04.fsf@yhuang-dev.intel.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/25.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=ascii Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Yang Shi writes: > swap_vma_readahead()'s comment is missed, just add it. > > Cc: Huang Ying > Cc: Tim Chen > Cc: Minchan Kim > Signed-off-by: Yang Shi Thank! Reviewed-by: "Huang, Ying" Best Regards, Huang, Ying > --- > v5: Fixed the comments per Ying Huang > > mm/swap_state.c | 16 +++++++++++++++- > 1 file changed, 15 insertions(+), 1 deletion(-) > > diff --git a/mm/swap_state.c b/mm/swap_state.c > index 78d500e..c8730d7 100644 > --- a/mm/swap_state.c > +++ b/mm/swap_state.c > @@ -523,7 +523,7 @@ static unsigned long swapin_nr_pages(unsigned long offset) > * This has been extended to use the NUMA policies from the mm triggering > * the readahead. > * > - * Caller must hold down_read on the vma->vm_mm if vmf->vma is not NULL. > + * Caller must hold read mmap_sem if vmf->vma is not NULL. > */ > struct page *swap_cluster_readahead(swp_entry_t entry, gfp_t gfp_mask, > struct vm_fault *vmf) > @@ -698,6 +698,20 @@ static void swap_ra_info(struct vm_fault *vmf, > pte_unmap(orig_pte); > } > > +/** > + * swap_vma_readahead - swap in pages in hope we need them soon > + * @entry: swap entry of this memory > + * @gfp_mask: memory allocation flags > + * @vmf: fault information > + * > + * Returns the struct page for entry and addr, after queueing swapin. > + * > + * Primitive swap readahead code. We simply read in a few pages whoes > + * virtual addresses are around the fault address in the same vma. > + * > + * Caller must hold read mmap_sem if vmf->vma is not NULL. > + * > + */ > static struct page *swap_vma_readahead(swp_entry_t fentry, gfp_t gfp_mask, > struct vm_fault *vmf) > {