From: Shaohui Zheng <[email protected]>
Extend memory probe interface to support an extra paramter nid,
the reserved memory can be added into this node if node exists.
Add a memory section(128M) to node 3(boots with mem=1024m)
echo 0x40000000,3 > memory/probe
And more we make it friendly, it is possible to add memory to do
echo 3g > memory/probe
echo 1024m,3 > memory/probe
It maintains backwards compatibility.
Another format suggested by Dave Hansen:
echo physical_address=0x40000000 numa_node=3 > memory/probe
it is more explicit to show meaning of the parameters.
Signed-off-by: Shaohui Zheng <[email protected]>
Signed-off-by: Haicheng Li <[email protected]>
Signed-off-by: Wu Fengguang <[email protected]>
---
Index: linux-hpe4/arch/x86/Kconfig
===================================================================
--- linux-hpe4.orig/arch/x86/Kconfig 2010-11-30 12:03:49.747622002 +0800
+++ linux-hpe4/arch/x86/Kconfig 2010-11-30 12:40:52.317621999 +0800
@@ -1276,10 +1276,6 @@
def_bool y
depends on ARCH_SPARSEMEM_ENABLE
-config ARCH_MEMORY_PROBE
- def_bool X86_64
- depends on MEMORY_HOTPLUG
-
config ILLEGAL_POINTER_VALUE
hex
default 0 if X86_32
Index: linux-hpe4/drivers/base/memory.c
===================================================================
--- linux-hpe4.orig/drivers/base/memory.c 2010-11-30 12:40:43.737622001 +0800
+++ linux-hpe4/drivers/base/memory.c 2010-11-30 12:42:15.467621626 +0800
@@ -329,26 +329,76 @@
* will not need to do it from userspace. The fake hot-add code
* as well as ppc64 will do all of their discovery in userspace
* and will require this interface.
+ *
+ * Parameter format 1: physical_address,numa_node
+ * Parameter format 2: physical_address=0x40000000 numa_node=3
*/
#ifdef CONFIG_ARCH_MEMORY_PROBE
-static ssize_t
-memory_probe_store(struct class *class, struct class_attribute *attr,
- const char *buf, size_t count)
+ssize_t parse_memory_probe_store(const char *buf, size_t count)
{
- u64 phys_addr;
- int nid;
+ u64 phys_addr = 0;
+ int nid = 0;
int ret;
+ char *p = NULL, *q = NULL;
+ /* format: physical_address=0x40000000 numa_node=3 */
+ p = strchr(buf, '=');
+ if (p != NULL) {
+ *p = '\0';
+ q = strchr(buf, ' ');
+ if (q == NULL) {
+ if (strcmp(buf, "physical_address") != 0)
+ ret = -EPERM;
+ else
+ phys_addr = memparse(p+1, NULL);
+ } else {
+ *q++ = '\0';
+ p = strchr(q, '=');
+ if (strcmp(buf, "physical_address") == 0)
+ phys_addr = memparse(p+1, NULL);
+ if (strcmp(buf, "numa_node") == 0)
+ nid = simple_strtoul(p+1, NULL, 0);
+ if (strcmp(q, "physical_address") == 0)
+ phys_addr = memparse(p+1, NULL);
+ if (strcmp(q, "numa_node") == 0)
+ nid = simple_strtoul(p+1, NULL, 0);
+ }
+ } else { /* physical_address,numa_node */
+ p = strchr(buf, ',');
+ if (p != NULL && strlen(p+1) > 0) {
+ /* nid specified */
+ *p++ = '\0';
+ nid = simple_strtoul(p, NULL, 0);
+ phys_addr = memparse(buf, NULL);
+ } else {
+ phys_addr = memparse(buf, NULL);
+ nid = memory_add_physaddr_to_nid(phys_addr);
+ }
+ }
- phys_addr = simple_strtoull(buf, NULL, 0);
-
- nid = memory_add_physaddr_to_nid(phys_addr);
- ret = add_memory(nid, phys_addr, PAGES_PER_SECTION << PAGE_SHIFT);
+ if (nid < 0 || nid > nr_node_ids - 1) {
+ printk(KERN_ERR "Invalid node id %d(0<=nid<%d).\n", nid, nr_node_ids);
+ ret = -EPERM;
+ } else {
+ printk(KERN_INFO "Add a memory section to node: %d.\n", nid);
+ ret = add_memory(nid, phys_addr, PAGES_PER_SECTION << PAGE_SHIFT);
+ if (ret)
+ count = ret;
+ }
if (ret)
count = ret;
return count;
}
+EXPORT_SYMBOL(parse_memory_probe_store);
+
+static ssize_t
+memory_probe_store(struct class *class, struct class_attribute *attr,
+ const char *buf, size_t count)
+{
+ return parse_memory_probe_store(buf, count);
+}
+
static CLASS_ATTR(probe, S_IWUSR, NULL, memory_probe_store);
static int memory_probe_init(void)
Index: linux-hpe4/mm/Kconfig
===================================================================
--- linux-hpe4.orig/mm/Kconfig 2010-11-30 12:03:49.747622002 +0800
+++ linux-hpe4/mm/Kconfig 2010-11-30 12:40:52.327621999 +0800
@@ -174,6 +174,17 @@
default "999999" if DEBUG_SPINLOCK || DEBUG_LOCK_ALLOC
default "4"
+config ARCH_MEMORY_PROBE
+ def_bool y
+ bool "Memory hotplug emulation"
+ depends on MEMORY_HOTPLUG
+ ---help---
+ Enable memory hotplug emulation. Reserve memory with grub parameter
+ "mem=N"(such as mem=1024M), where N is the initial memory size, the
+ rest physical memory will be removed from e820 table; the memory probe
+ interface is for memory hot-add to specified node in software method.
+ This is for debuging and testing purpose
+
#
# support for memory compaction
config COMPACTION
Index: linux-hpe4/include/linux/memory_hotplug.h
===================================================================
--- linux-hpe4.orig/include/linux/memory_hotplug.h 2010-11-30 12:40:43.737622001 +0800
+++ linux-hpe4/include/linux/memory_hotplug.h 2010-11-30 12:40:52.337622000 +0800
@@ -211,5 +211,13 @@
extern void sparse_remove_one_section(struct zone *zone, struct mem_section *ms);
extern struct page *sparse_decode_mem_map(unsigned long coded_mem_map,
unsigned long pnum);
+#ifdef CONFIG_ARCH_MEMORY_PROBE
+extern ssize_t parse_memory_probe_store(const char *buf, size_t count);
+#else
+static inline ssize_t parse_memory_probe_store(const char *buf, size_t count)
+{
+ return 0;
+}
+#endif /* CONFIG_ARCH_MEMORY_PROBE */
#endif /* __LINUX_MEMORY_HOTPLUG_H */
--
Thanks & Regards,
Shaohui
On Tue, 30 Nov 2010, [email protected] wrote:
> From: Shaohui Zheng <[email protected]>
>
> Extend memory probe interface to support an extra paramter nid,
> the reserved memory can be added into this node if node exists.
>
> Add a memory section(128M) to node 3(boots with mem=1024m)
>
> echo 0x40000000,3 > memory/probe
>
> And more we make it friendly, it is possible to add memory to do
>
> echo 3g > memory/probe
> echo 1024m,3 > memory/probe
>
> It maintains backwards compatibility.
>
> Another format suggested by Dave Hansen:
>
> echo physical_address=0x40000000 numa_node=3 > memory/probe
>
> it is more explicit to show meaning of the parameters.
>
I don't like this interface, I think it would be much better to map the
memory region to the desired node id prior to using probe as an extention
to debugfs.