From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Kirill A. Shutemov" Subject: Re: [PATCH 34/34] mm: dynamically allocate page->ptl if it cannot be embedded to struct page Date: Tue, 15 Oct 2013 01:26:53 +0300 (EEST) Message-ID: <20131014222653.86EE1E0090@blue.fi.intel.com> References: <1381428359-14843-1-git-send-email-kirill.shutemov@linux.intel.com> <1381428359-14843-35-git-send-email-kirill.shutemov@linux.intel.com> <00000141a3f48ada-37ee9c14-2f2b-40a2-93f4-70258363351b-000000@email.amazonses.com> <20131010200921.91D84E0090@blue.fi.intel.com> <00000141a7d2aa7b-e59f292a-746c-4f55-aa51-9fa060a7fbeb-000000@email.amazonses.com> <20131014090437.F22CBE0090@blue.fi.intel.com> <00000141b85a90a0-7cf6bab0-4c17-4fc0-8224-74bbb1fc85ee-000000@email.amazonses.com> <20131014212514.C7C19E0090@blue.fi.intel.com> <00000141b90841a8-3fb61f1e-89aa-4a35-94d4-a264ac91462b-000000@email.amazonses.com> Content-Transfer-Encoding: 7bit Return-path: Received: from mga11.intel.com ([192.55.52.93]:31475 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756864Ab3JNW05 (ORCPT ); Mon, 14 Oct 2013 18:26:57 -0400 In-Reply-To: <00000141b90841a8-3fb61f1e-89aa-4a35-94d4-a264ac91462b-000000@email.amazonses.com> Sender: linux-arch-owner@vger.kernel.org List-ID: To: Christoph Lameter Cc: "Kirill A. Shutemov" , Andrew Morton , Peter Zijlstra , Ingo Molnar , linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-arch@vger.kernel.org Christoph Lameter wrote: > On Tue, 15 Oct 2013, Kirill A. Shutemov wrote: > > > Feel free to propose a patch. I don't see much point. > > Right now you are using a long to stand in for a spinlock_t or a pointer > to a spinlock_t. An #ifdef would allow to define the proper type and > therefore the compiler to check that the ptl is correctly used. You should not use it directly anyway: page->ptl is not there at all if USE_SPLIT_PTE_PTLOCKS is 0. Compiler checks limited to few helpers and use a kbuild hack is overkill to me. -- Kirill A. Shutemov