From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e31.co.us.ibm.com (e31.co.us.ibm.com [32.97.110.149]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "e31.co.us.ibm.com", Issuer "Equifax" (verified OK)) by ozlabs.org (Postfix) with ESMTPS id BCBE1B6EF3 for ; Tue, 20 Jul 2010 23:26:45 +1000 (EST) Received: from d03relay03.boulder.ibm.com (d03relay03.boulder.ibm.com [9.17.195.228]) by e31.co.us.ibm.com (8.14.4/8.13.1) with ESMTP id o6KDFTNa006285 for ; Tue, 20 Jul 2010 07:15:29 -0600 Received: from d03av02.boulder.ibm.com (d03av02.boulder.ibm.com [9.17.195.168]) by d03relay03.boulder.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id o6KDQf9V121606 for ; Tue, 20 Jul 2010 07:26:41 -0600 Received: from d03av02.boulder.ibm.com (loopback [127.0.0.1]) by d03av02.boulder.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id o6KDQexw022980 for ; Tue, 20 Jul 2010 07:26:41 -0600 Message-ID: <4C45A40F.3020703@austin.ibm.com> Date: Tue, 20 Jul 2010 08:26:39 -0500 From: Nathan Fontenot MIME-Version: 1.0 To: linux-kernel@vger.kernel.org, linux-mm@kvack.org, linuxppc-dev@ozlabs.org Subject: Re: [PATCH 3/8] v3 Add section count to memory_block References: <4C451BF5.50304@austin.ibm.com> <4C451DD6.3080005@austin.ibm.com> In-Reply-To: <4C451DD6.3080005@austin.ibm.com> Content-Type: text/plain; charset=ISO-8859-1 Cc: greg@kroah.com, KAMEZAWA Hiroyuki List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Add a section count property to the memory_block struct to track the number of memory sections that have been added/removed from a memory block. Updated to use atomic_dec_and_test(). Signed-off-by: Nathan Fontenot --- drivers/base/memory.c | 18 +++++++++++------- include/linux/memory.h | 2 ++ 2 files changed, 13 insertions(+), 7 deletions(-) Index: linux-2.6/drivers/base/memory.c =================================================================== --- linux-2.6.orig/drivers/base/memory.c 2010-07-20 06:38:21.000000000 -0500 +++ linux-2.6/drivers/base/memory.c 2010-07-20 06:43:29.000000000 -0500 @@ -487,6 +487,7 @@ static int add_memory_block(int nid, str mem->start_phys_index = __section_nr(section); mem->state = state; + atomic_inc(&mem->section_count); mutex_init(&mem->state_mutex); start_pfn = section_nr_to_pfn(mem->start_phys_index); mem->phys_device = arch_get_memory_phys_device(start_pfn); @@ -516,13 +517,16 @@ int remove_memory_block(unsigned long no struct memory_block *mem; mem = find_memory_block(section); - unregister_mem_sect_under_nodes(mem); - mem_remove_simple_file(mem, phys_index); - mem_remove_simple_file(mem, end_phys_index); - mem_remove_simple_file(mem, state); - mem_remove_simple_file(mem, phys_device); - mem_remove_simple_file(mem, removable); - unregister_memory(mem, section); + + if (atomic_dec_and_test(&mem->section_count)) { + unregister_mem_sect_under_nodes(mem); + mem_remove_simple_file(mem, phys_index); + mem_remove_simple_file(mem, end_phys_index); + mem_remove_simple_file(mem, state); + mem_remove_simple_file(mem, phys_device); + mem_remove_simple_file(mem, removable); + unregister_memory(mem, section); + } return 0; } Index: linux-2.6/include/linux/memory.h =================================================================== --- linux-2.6.orig/include/linux/memory.h 2010-07-20 06:35:38.000000000 -0500 +++ linux-2.6/include/linux/memory.h 2010-07-20 06:38:59.000000000 -0500 @@ -19,11 +19,13 @@ #include #include #include +#include struct memory_block { unsigned long start_phys_index; unsigned long end_phys_index; unsigned long state; + atomic_t section_count; /* * This serializes all state change requests. It isn't * held during creation because the control files are