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[70.31.27.79]) by smtp.gmail.com with ESMTPSA id u5-20020a05622a17c500b0035d0655b079sm14386325qtk.30.2022.10.05.13.29.09 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 05 Oct 2022 13:29:10 -0700 (PDT) Date: Wed, 5 Oct 2022 16:29:08 -0400 From: Peter Xu To: David Hildenbrand Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org, Andrew Morton , Shuah Khan , Hugh Dickins , Vlastimil Babka , Andrea Arcangeli , "Matthew Wilcox (Oracle)" , Jason Gunthorpe , John Hubbard Subject: Re: [PATCH v1 2/7] mm/ksm: simplify break_ksm() to not rely on VM_FAULT_WRITE Message-ID: References: <20220930141931.174362-1-david@redhat.com> <20220930141931.174362-3-david@redhat.com> MIME-Version: 1.0 In-Reply-To: <20220930141931.174362-3-david@redhat.com> X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Disposition: inline ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1665001753; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=9WhHrCKV1cwvD4EM7naK+YDuH8wkC6i7kWGC/pb6hko=; b=JJqrgLttYz5yjyN9n/85rkAD/Hb+na+VqqzpbZ6Qizylk3WEKkjxDBndpR6p1UpzsloLwa mj91aPiwBZUoKalk2Krsb4c3GNEHGRYgVezMmUavjhSPjB5AeiF4JLas6ycKzyvxpVqngv p+nu4ycwh+y/GPn5JWRjVlxYwpEQ8zU= ARC-Authentication-Results: i=1; imf13.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=Ob8AeOD3; spf=pass (imf13.hostedemail.com: domain of peterx@redhat.com designates 170.10.129.124 as permitted sender) smtp.mailfrom=peterx@redhat.com; dmarc=pass (policy=none) header.from=redhat.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1665001753; a=rsa-sha256; cv=none; b=Onq01lduZQhMVQSyGb2zHbFPHttHJcifkFPZEECny0otF77NUdXT2BYG6zpOef6r4MKk48 EGEynqv/w6U2YKtBNTmQeZDI5cyODHhk/ejtX+Xjn8o8jLwIfi6nXPMIuEaeZRHdYZF+BE WB0khwiEHxZAUQ1pZ9FyZXu/Wvhzd0w= Authentication-Results: imf13.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=Ob8AeOD3; spf=pass (imf13.hostedemail.com: domain of peterx@redhat.com designates 170.10.129.124 as permitted sender) smtp.mailfrom=peterx@redhat.com; dmarc=pass (policy=none) header.from=redhat.com X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: 47BEF2001F X-Rspam-User: X-Stat-Signature: y4hhj8iiu5e6bm3h71bm5no8wkpcmkm6 X-HE-Tag: 1665001753-132412 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Fri, Sep 30, 2022 at 04:19:26PM +0200, David Hildenbrand wrote: > I don't think that we particularly care about that performance drop when > unmerging. If it ever turns out to be an actual performance issue, we can > think about a better alternative for FAULT_FLAG_UNSHARE -- let's just keep > it simple for now. It'll be nice to hear from real ksm users for sure. But to me this makes sense, and the patch itself looks good to me, I think that also means: Acked-by: Peter Xu -- Peter Xu