From 4a0b2b4dbe1335b8b9886ba3dc85a145d5d938ed Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Tue, 1 Jul 2008 18:48:41 +0200 Subject: sysdev: Pass the attribute to the low level sysdev show/store function This allow to dynamically generate attributes and share show/store functions between attributes. Right now most attributes are generated by special macros and lots of duplicated code. With the attribute passed it's instead possible to attach some data to the attribute and then use that in shared low level functions to do different things. I need this for the dynamically generated bank attributes in the x86 machine check code, but it'll allow some further cleanups. I converted all users in tree to the new show/store prototype. It's a single huge patch to avoid unbisectable sections. Runtime tested: x86-32, x86-64 Compiled only: ia64, powerpc Not compile tested/only grep converted: sh, arm, avr32 Signed-off-by: Andi Kleen Signed-off-by: Greg Kroah-Hartman --- drivers/base/memory.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) (limited to 'drivers/base/memory.c') diff --git a/drivers/base/memory.c b/drivers/base/memory.c index 937e8258981..4d4e0e7b6e9 100644 --- a/drivers/base/memory.c +++ b/drivers/base/memory.c @@ -92,7 +92,8 @@ unregister_memory(struct memory_block *memory, struct mem_section *section) * uses. */ -static ssize_t show_mem_phys_index(struct sys_device *dev, char *buf) +static ssize_t show_mem_phys_index(struct sys_device *dev, + struct sysdev_attribute *attr, char *buf) { struct memory_block *mem = container_of(dev, struct memory_block, sysdev); @@ -102,7 +103,8 @@ static ssize_t show_mem_phys_index(struct sys_device *dev, char *buf) /* * online, offline, going offline, etc. */ -static ssize_t show_mem_state(struct sys_device *dev, char *buf) +static ssize_t show_mem_state(struct sys_device *dev, + struct sysdev_attribute *attr, char *buf) { struct memory_block *mem = container_of(dev, struct memory_block, sysdev); @@ -217,7 +219,8 @@ out: } static ssize_t -store_mem_state(struct sys_device *dev, const char *buf, size_t count) +store_mem_state(struct sys_device *dev, + struct sysdev_attribute *attr, const char *buf, size_t count) { struct memory_block *mem; unsigned int phys_section_nr; @@ -248,7 +251,8 @@ out: * s.t. if I offline all of these sections I can then * remove the physical device? */ -static ssize_t show_phys_device(struct sys_device *dev, char *buf) +static ssize_t show_phys_device(struct sys_device *dev, + struct sysdev_attribute *attr, char *buf) { struct memory_block *mem = container_of(dev, struct memory_block, sysdev); -- cgit v1.2.3-70-g09d2 From 5c755e9fd813810680abd56ec09a5f90143e815b Mon Sep 17 00:00:00 2001 From: Badari Pulavarty Date: Wed, 23 Jul 2008 21:28:19 -0700 Subject: memory-hotplug: add sysfs removable attribute for hotplug memory remove Memory may be hot-removed on a per-memory-block basis, particularly on POWER where the SPARSEMEM section size often matches the memory-block size. A user-level agent must be able to identify which sections of memory are likely to be removable before attempting the potentially expensive operation. This patch adds a file called "removable" to the memory directory in sysfs to help such an agent. In this patch, a memory block is considered removable if; o It contains only MOVABLE pageblocks o It contains only pageblocks with free pages regardless of pageblock type On the other hand, a memory block starting with a PageReserved() page will never be considered removable. Without this patch, the user-agent is forced to choose a memory block to remove randomly. Sample output of the sysfs files: ./memory/memory0/removable: 0 ./memory/memory1/removable: 0 ./memory/memory2/removable: 0 ./memory/memory3/removable: 0 ./memory/memory4/removable: 0 ./memory/memory5/removable: 0 ./memory/memory6/removable: 0 ./memory/memory7/removable: 1 ./memory/memory8/removable: 0 ./memory/memory9/removable: 0 ./memory/memory10/removable: 0 ./memory/memory11/removable: 0 ./memory/memory12/removable: 0 ./memory/memory13/removable: 0 ./memory/memory14/removable: 0 ./memory/memory15/removable: 0 ./memory/memory16/removable: 0 ./memory/memory17/removable: 1 ./memory/memory18/removable: 1 ./memory/memory19/removable: 1 ./memory/memory20/removable: 1 ./memory/memory21/removable: 1 ./memory/memory22/removable: 1 Signed-off-by: Badari Pulavarty Signed-off-by: Mel Gorman Acked-by: KAMEZAWA Hiroyuki Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/ABI/testing/sysfs-devices-memory | 24 +++++++++++ drivers/base/memory.c | 19 ++++++++ include/linux/memory_hotplug.h | 12 ++++++ mm/memory_hotplug.c | 60 ++++++++++++++++++++++++++ 4 files changed, 115 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-devices-memory (limited to 'drivers/base/memory.c') diff --git a/Documentation/ABI/testing/sysfs-devices-memory b/Documentation/ABI/testing/sysfs-devices-memory new file mode 100644 index 00000000000..7a16fe1e227 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-devices-memory @@ -0,0 +1,24 @@ +What: /sys/devices/system/memory +Date: June 2008 +Contact: Badari Pulavarty +Description: + The /sys/devices/system/memory contains a snapshot of the + internal state of the kernel memory blocks. Files could be + added or removed dynamically to represent hot-add/remove + operations. + +Users: hotplug memory add/remove tools + https://w3.opensource.ibm.com/projects/powerpc-utils/ + +What: /sys/devices/system/memory/memoryX/removable +Date: June 2008 +Contact: Badari Pulavarty +Description: + The file /sys/devices/system/memory/memoryX/removable + indicates whether this memory block is removable or not. + This is useful for a user-level agent to determine + identify removable sections of the memory before attempting + potentially expensive hot-remove memory operation + +Users: hotplug memory remove tools + https://w3.opensource.ibm.com/projects/powerpc-utils/ diff --git a/drivers/base/memory.c b/drivers/base/memory.c index 4d4e0e7b6e9..855ed1a9f97 100644 --- a/drivers/base/memory.c +++ b/drivers/base/memory.c @@ -100,6 +100,21 @@ static ssize_t show_mem_phys_index(struct sys_device *dev, return sprintf(buf, "%08lx\n", mem->phys_index); } +/* + * Show whether the section of memory is likely to be hot-removable + */ +static ssize_t show_mem_removable(struct sys_device *dev, char *buf) +{ + unsigned long start_pfn; + int ret; + struct memory_block *mem = + container_of(dev, struct memory_block, sysdev); + + start_pfn = section_nr_to_pfn(mem->phys_index); + ret = is_mem_section_removable(start_pfn, PAGES_PER_SECTION); + return sprintf(buf, "%d\n", ret); +} + /* * online, offline, going offline, etc. */ @@ -262,6 +277,7 @@ static ssize_t show_phys_device(struct sys_device *dev, static SYSDEV_ATTR(phys_index, 0444, show_mem_phys_index, NULL); static SYSDEV_ATTR(state, 0644, show_mem_state, store_mem_state); static SYSDEV_ATTR(phys_device, 0444, show_phys_device, NULL); +static SYSDEV_ATTR(removable, 0444, show_mem_removable, NULL); #define mem_create_simple_file(mem, attr_name) \ sysdev_create_file(&mem->sysdev, &attr_##attr_name) @@ -350,6 +366,8 @@ static int add_memory_block(unsigned long node_id, struct mem_section *section, ret = mem_create_simple_file(mem, state); if (!ret) ret = mem_create_simple_file(mem, phys_device); + if (!ret) + ret = mem_create_simple_file(mem, removable); return ret; } @@ -394,6 +412,7 @@ int remove_memory_block(unsigned long node_id, struct mem_section *section, mem_remove_simple_file(mem, 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; diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h index 3628e5088f6..763ba81fc0f 100644 --- a/include/linux/memory_hotplug.h +++ b/include/linux/memory_hotplug.h @@ -199,6 +199,18 @@ extern int walk_memory_resource(unsigned long start_pfn, unsigned long nr_pages, void *arg, int (*func)(unsigned long, unsigned long, void *)); +#ifdef CONFIG_MEMORY_HOTREMOVE + +extern int is_mem_section_removable(unsigned long pfn, unsigned long nr_pages); + +#else +static inline int is_mem_section_removable(unsigned long pfn, + unsigned long nr_pages) +{ + return 0; +} +#endif /* CONFIG_MEMORY_HOTREMOVE */ + extern int add_memory(int nid, u64 start, u64 size); extern int arch_add_memory(int nid, u64 start, u64 size); extern int remove_memory(u64 start, u64 size); diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 93aba78dc8b..89fee2dcb03 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -522,6 +522,66 @@ error: EXPORT_SYMBOL_GPL(add_memory); #ifdef CONFIG_MEMORY_HOTREMOVE +/* + * A free page on the buddy free lists (not the per-cpu lists) has PageBuddy + * set and the size of the free page is given by page_order(). Using this, + * the function determines if the pageblock contains only free pages. + * Due to buddy contraints, a free page at least the size of a pageblock will + * be located at the start of the pageblock + */ +static inline int pageblock_free(struct page *page) +{ + return PageBuddy(page) && page_order(page) >= pageblock_order; +} + +/* Return the start of the next active pageblock after a given page */ +static struct page *next_active_pageblock(struct page *page) +{ + int pageblocks_stride; + + /* Ensure the starting page is pageblock-aligned */ + BUG_ON(page_to_pfn(page) & (pageblock_nr_pages - 1)); + + /* Move forward by at least 1 * pageblock_nr_pages */ + pageblocks_stride = 1; + + /* If the entire pageblock is free, move to the end of free page */ + if (pageblock_free(page)) + pageblocks_stride += page_order(page) - pageblock_order; + + return page + (pageblocks_stride * pageblock_nr_pages); +} + +/* Checks if this range of memory is likely to be hot-removable. */ +int is_mem_section_removable(unsigned long start_pfn, unsigned long nr_pages) +{ + int type; + struct page *page = pfn_to_page(start_pfn); + struct page *end_page = page + nr_pages; + + /* Check the starting page of each pageblock within the range */ + for (; page < end_page; page = next_active_pageblock(page)) { + type = get_pageblock_migratetype(page); + + /* + * A pageblock containing MOVABLE or free pages is considered + * removable + */ + if (type != MIGRATE_MOVABLE && !pageblock_free(page)) + return 0; + + /* + * A pageblock starting with a PageReserved page is not + * considered removable. + */ + if (PageReserved(page)) + return 0; + } + + /* All pageblocks in the memory block are likely to be hot-removable */ + return 1; +} + /* * Confirm all pages in a range [start, end) is belongs to the same zone. */ -- cgit v1.2.3-70-g09d2 From f810a5cf28a818db96333cd23646f0227ec015b4 Mon Sep 17 00:00:00 2001 From: Arjan van de Ven Date: Fri, 25 Jul 2008 19:45:39 -0700 Subject: Use WARN() in drivers/base/ Use WARN() instead of a printk+WARN_ON() pair; this way the message becomes part of the warning section for better reporting/collection. Signed-off-by: Arjan van de Ven Cc: Greg KH Cc: Kay Sievers Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/base/core.c | 6 ++---- drivers/base/memory.c | 3 +-- drivers/base/sys.c | 12 ++++-------- 3 files changed, 7 insertions(+), 14 deletions(-) (limited to 'drivers/base/memory.c') diff --git a/drivers/base/core.c b/drivers/base/core.c index 7d5c63c81a5..068aa1c9538 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -116,12 +116,10 @@ static void device_release(struct kobject *kobj) dev->type->release(dev); else if (dev->class && dev->class->dev_release) dev->class->dev_release(dev); - else { - printk(KERN_ERR "Device '%s' does not have a release() " + else + WARN(1, KERN_ERR "Device '%s' does not have a release() " "function, it is broken and must be fixed.\n", dev->bus_id); - WARN_ON(1); - } } static struct kobj_type device_ktype = { diff --git a/drivers/base/memory.c b/drivers/base/memory.c index 855ed1a9f97..3ad49a00029 100644 --- a/drivers/base/memory.c +++ b/drivers/base/memory.c @@ -204,9 +204,8 @@ memory_block_action(struct memory_block *mem, unsigned long action) } break; default: - printk(KERN_WARNING "%s(%p, %ld) unknown action: %ld\n", + WARN(1, KERN_WARNING "%s(%p, %ld) unknown action: %ld\n", __func__, mem, action, action); - WARN_ON(1); ret = -EINVAL; } diff --git a/drivers/base/sys.c b/drivers/base/sys.c index 40fc14f0354..75dd6e22faf 100644 --- a/drivers/base/sys.c +++ b/drivers/base/sys.c @@ -168,19 +168,16 @@ int sysdev_driver_register(struct sysdev_class *cls, struct sysdev_driver *drv) int err = 0; if (!cls) { - printk(KERN_WARNING "sysdev: invalid class passed to " + WARN(1, KERN_WARNING "sysdev: invalid class passed to " "sysdev_driver_register!\n"); - WARN_ON(1); return -EINVAL; } /* Check whether this driver has already been added to a class. */ - if (drv->entry.next && !list_empty(&drv->entry)) { - printk(KERN_WARNING "sysdev: class %s: driver (%p) has already" + if (drv->entry.next && !list_empty(&drv->entry)) + WARN(1, KERN_WARNING "sysdev: class %s: driver (%p) has already" " been registered to a class, something is wrong, but " "will forge on!\n", cls->name, drv); - WARN_ON(1); - } mutex_lock(&sysdev_drivers_lock); if (cls && kset_get(&cls->kset)) { @@ -194,8 +191,7 @@ int sysdev_driver_register(struct sysdev_class *cls, struct sysdev_driver *drv) } } else { err = -EINVAL; - printk(KERN_ERR "%s: invalid device class\n", __func__); - WARN_ON(1); + WARN(1, KERN_ERR "%s: invalid device class\n", __func__); } mutex_unlock(&sysdev_drivers_lock); return err; -- cgit v1.2.3-70-g09d2 From 1f07be1c31cf898e5e3708d52e38db0803c62924 Mon Sep 17 00:00:00 2001 From: Stephen Rothwell Date: Mon, 28 Jul 2008 11:05:04 +1000 Subject: more sysdev API change fallout - drivers/base/memory.c Noticed because of this warning: drivers/base/memory.c:279: warning: initialization from incompatible pointer type Signed-off-by: Stephen Rothwell Signed-off-by: Linus Torvalds --- drivers/base/memory.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'drivers/base/memory.c') diff --git a/drivers/base/memory.c b/drivers/base/memory.c index 3ad49a00029..af0d175c025 100644 --- a/drivers/base/memory.c +++ b/drivers/base/memory.c @@ -103,7 +103,8 @@ static ssize_t show_mem_phys_index(struct sys_device *dev, /* * Show whether the section of memory is likely to be hot-removable */ -static ssize_t show_mem_removable(struct sys_device *dev, char *buf) +static ssize_t show_mem_removable(struct sys_device *dev, + struct sysdev_attribute *attr, char *buf) { unsigned long start_pfn; int ret; -- cgit v1.2.3-70-g09d2