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

Nathan Fontenot
2010-07-20T03:54:04Z

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) {
+ 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