Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756172AbbKDCPc (ORCPT ); Tue, 3 Nov 2015 21:15:32 -0500 Received: from mail-pa0-f66.google.com ([209.85.220.66]:33720 "EHLO mail-pa0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754815AbbKDCPa (ORCPT ); Tue, 3 Nov 2015 21:15:30 -0500 Date: Wed, 4 Nov 2015 11:16:24 +0900 From: Sergey Senozhatsky To: Minchan Kim Cc: Andrew Morton , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Michael Kerrisk , linux-api@vger.kernel.org, Hugh Dickins , Johannes Weiner , Rik van Riel , Mel Gorman , KOSAKI Motohiro , Jason Evans , Daniel Micay , "Kirill A. Shutemov" , Shaohua Li , Michal Hocko , yalin.wang2010@gmail.com, Sergey Senozhatsky Subject: Re: [PATCH v2 01/13] mm: support madvise(MADV_FREE) Message-ID: <20151104021624.GA2476@swordfish> References: <1446600367-7976-1-git-send-email-minchan@kernel.org> <1446600367-7976-2-git-send-email-minchan@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1446600367-7976-2-git-send-email-minchan@kernel.org> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1201 Lines: 38 Hi Minchan, On (11/04/15 10:25), Minchan Kim wrote: [..] >+static int madvise_free_pte_range(pmd_t *pmd, unsigned long addr, >+ unsigned long end, struct mm_walk *walk) >+ ... > + if (pmd_trans_unstable(pmd)) > + return 0; I think it makes sense to update pmd_trans_unstable() and pmd_none_or_trans_huge_or_clear_bad() comments in asm-generic/pgtable.h Because they explicitly mention MADV_DONTNEED only. Just a thought. > @@ -379,6 +502,14 @@ madvise_vma(struct vm_area_struct *vma, struct vm_area_struct **prev, > return madvise_remove(vma, prev, start, end); > case MADV_WILLNEED: > return madvise_willneed(vma, prev, start, end); > + case MADV_FREE: > + /* > + * XXX: In this implementation, MADV_FREE works like ^^^^ XXX > + * MADV_DONTNEED on swapless system or full swap. > + */ > + if (get_nr_swap_pages() > 0) > + return madvise_free(vma, prev, start, end); > + /* passthrough */ -ss -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/