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. CC: Dave Hansen <dave@xxxxxxxxxxxxxxxxxx> Signed-off-by: Shaohui Zheng <shaohui.zheng@xxxxxxxxx> Signed-off-by: Haicheng Li <haicheng.li@xxxxxxxxx> Signed-off-by: Wu Fengguang <fengguang.wu@xxxxxxxxx> --- Index: linux-hpe4/Documentation/ABI/testing/sysfs-devices-memory =================================================================== --- linux-hpe4.orig/Documentation/ABI/testing/sysfs-devices-memory 2010-11-17 09:00:50.653461798 +0800 +++ linux-hpe4/Documentation/ABI/testing/sysfs-devices-memory 2010-11-17 09:01:10.262838849 +0800 @@ -60,6 +60,23 @@ Users: hotplug memory remove tools http://www.ibm.com/developerworks/wikis/display/LinuxP/powerpc-utils +What: /sys/devices/system/memory/probe +Date: Nov 2010 +Contact: Linux Memory Management list <linux-mm@xxxxxxxxx> +Description: + memory probe interface is for memory hotplug emulation. it is a software + interface to test memory hotplug. We provide the start address and numa + nodes id, it will add a memory section to the specified node. + + Add a memory section(128M) to node 3(boots with mem=1024m) + echo 0x40000000,3 > memory/probe + + A more friendly method + echo 3g > memory/probe + echo 1024m,3 > memory/probe + + Another format suggested by Dave Hansen: + echo physical_address=0x40000000 numa_node=3 > memory/probe What: /sys/devices/system/memoryX/nodeY Date: October 2009 Index: linux-hpe4/arch/x86/Kconfig =================================================================== --- linux-hpe4.orig/arch/x86/Kconfig 2010-11-17 09:00:50.673463029 +0800 +++ linux-hpe4/arch/x86/Kconfig 2010-11-17 09:01:10.282838829 +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 2010-11-17 09:00:50.673463029 +0800 +++ linux-hpe4/drivers/base/memory.c 2010-11-17 09:01:10.302838792 +0800 @@ -329,6 +329,9 @@ * 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 @@ 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; Index: linux-hpe4/mm/Kconfig =================================================================== --- linux-hpe4.orig/mm/Kconfig 2010-11-17 09:01:10.212839478 +0800 +++ linux-hpe4/mm/Kconfig 2010-11-17 09:01:10.302838792 +0800 @@ -173,6 +173,17 @@ 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 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom policy in Canada: sign http://dissolvethecrtc.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>