2010-11-13 07:38:07

by Zheng, Shaohui

[permalink] [raw]
Subject: [v2,7/8] NUMA Hotplug emulator


From: Shaohui Zheng <[email protected]>
Subject: hotplug emulator:extend memory probe interface to support NUMA

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.

Signed-off-by: Shaohui Zheng <[email protected]>
Signed-off-by: Haicheng Li <[email protected]>
Signed-off-by: Wu Fengguang <[email protected]>
---
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index dcb0593..0750409 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -1273,10 +1273,6 @@ config ARCH_SELECT_MEMORY_MODEL
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
diff --git a/drivers/base/memory.c b/drivers/base/memory.c
index 933442f..32c16a2 100644
--- a/drivers/base/memory.c
+++ b/drivers/base/memory.c
@@ -329,6 +329,9 @@ static int block_size_init(void)
* 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
@@ -336,13 +339,53 @@ memory_probe_store(struct class *class, struct class_attribute *attr,
const char *buf, size_t count)
{
u64 phys_addr;
- int nid;
+ 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;
diff --git a/mm/Kconfig b/mm/Kconfig
index 78bb447..a0b5c3d 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -170,6 +170,17 @@ config ARCH_CPU_PROBE_RELEASE
is for cpu hot-add/hot-remove to specified node in software method.
This is for debuging and testing purpose

+config ARCH_MEMORY_PROBE
+ def_bool y
+ bool "Memory hotplug emulation"
+ depends on NUMA_HOTPLUG_EMU
+ ---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
+
#
# If we have space for more page flags then we can enable additional
# optimizations and functionality.

--
Thanks & Regards,
Shaohui