Patchwork [3/8] v3 Add section count to memory_block

login
register
mail settings
Submitter Nathan Fontenot
Date July 20, 2010, 3:53 a.m.
Message ID <4C451DD6.3080005@austin.ibm.com>
Download mbox | patch
Permalink /patch/59273/
State Superseded
Delegated to: Benjamin Herrenschmidt
Headers show

Comments

Nathan Fontenot - July 20, 2010, 3:53 a.m.
Add a section count property to the memory_block struct to track the number
of memory sections that have been added/removed from a emory block.

Signed-off-by: Nathan Fontenot <nfont@asutin.ibm.com>
---
 drivers/base/memory.c  |   19 ++++++++++++-------
 include/linux/memory.h |    2 ++
 2 files changed, 14 insertions(+), 7 deletions(-)
KAMEZAWA Hiroyuki - July 20, 2010, 7:01 a.m.
On Mon, 19 Jul 2010 22:53:58 -0500
Nathan Fontenot <nfont@austin.ibm.com> wrote:

> Add a section count property to the memory_block struct to track the number
> of memory sections that have been added/removed from a emory block.
> 
> Signed-off-by: Nathan Fontenot <nfont@asutin.ibm.com>
> ---
>  drivers/base/memory.c  |   19 ++++++++++++-------
>  include/linux/memory.h |    2 ++
>  2 files changed, 14 insertions(+), 7 deletions(-)
> 
> Index: linux-2.6/drivers/base/memory.c
> ===================================================================
> --- linux-2.6.orig/drivers/base/memory.c	2010-07-19 20:43:49.000000000 -0500
> +++ linux-2.6/drivers/base/memory.c	2010-07-19 20:44:01.000000000 -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 +517,17 @@ 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, start_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);
> +	atomic_dec(&mem->section_count);
> +
> +	if (atomic_read(&mem->section_count) == 0) {

We use atomic_dec_and_test() in usual.

Otherwise, I don't see other problems in other part. Please fix this nitpick.

Regards,
-Kame

Patch

Index: linux-2.6/drivers/base/memory.c
===================================================================
--- linux-2.6.orig/drivers/base/memory.c	2010-07-19 20:43:49.000000000 -0500
+++ linux-2.6/drivers/base/memory.c	2010-07-19 20:44:01.000000000 -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 +517,17 @@  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, start_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);
+	atomic_dec(&mem->section_count);
+
+	if (atomic_read(&mem->section_count) == 0) {
+		unregister_mem_sect_under_nodes(mem);
+		mem_remove_simple_file(mem, start_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	2010-07-19 20:43:49.000000000 -0500
+++ linux-2.6/include/linux/memory.h	2010-07-19 20:44:01.000000000 -0500
@@ -19,11 +19,13 @@ 
 #include <linux/node.h>
 #include <linux/compiler.h>
 #include <linux/mutex.h>
+#include <asm/atomic.h>
 
 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