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author | Toshi Kani <toshi.kani@hp.com> | 2013-11-12 15:07:25 -0800 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2013-11-13 12:09:04 +0900 |
commit | 01b0f19707c51ef247404e6af1d4a97a11ba34f7 (patch) | |
tree | 0e266339d6a644acdb7300c1a6bbad4106c68d57 | |
parent | 309d0b3917387b48d1fa1a15aa6762de489c9123 (diff) | |
download | linux-01b0f19707c51ef247404e6af1d4a97a11ba34f7.tar.gz linux-01b0f19707c51ef247404e6af1d4a97a11ba34f7.tar.bz2 linux-01b0f19707c51ef247404e6af1d4a97a11ba34f7.zip |
cpu/mem hotplug: add try_online_node() for cpu_up()
cpu_up() has #ifdef CONFIG_MEMORY_HOTPLUG code blocks, which call
mem_online_node() to put its node online if offlined and then call
build_all_zonelists() to initialize the zone list.
These steps are specific to memory hotplug, and should be managed in
mm/memory_hotplug.c. lock_memory_hotplug() should also be held for the
whole steps.
For this reason, this patch replaces mem_online_node() with
try_online_node(), which performs the whole steps with
lock_memory_hotplug() held. try_online_node() is named after
try_offline_node() as they have similar purpose.
There is no functional change in this patch.
Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r-- | include/linux/memory_hotplug.h | 8 | ||||
-rw-r--r-- | kernel/cpu.c | 29 | ||||
-rw-r--r-- | mm/memory_hotplug.c | 16 |
3 files changed, 24 insertions, 29 deletions
diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h index dd38e62b84d2..22203c293f07 100644 --- a/include/linux/memory_hotplug.h +++ b/include/linux/memory_hotplug.h @@ -94,6 +94,8 @@ extern void __online_page_set_limits(struct page *page); extern void __online_page_increment_counters(struct page *page); extern void __online_page_free(struct page *page); +extern int try_online_node(int nid); + #ifdef CONFIG_MEMORY_HOTREMOVE extern bool is_pageblock_removable_nolock(struct page *page); extern int arch_remove_memory(u64 start, u64 size); @@ -225,6 +227,11 @@ static inline void register_page_bootmem_info_node(struct pglist_data *pgdat) { } +static inline int try_online_node(int nid) +{ + return 0; +} + static inline void lock_memory_hotplug(void) {} static inline void unlock_memory_hotplug(void) {} @@ -256,7 +263,6 @@ static inline void remove_memory(int nid, u64 start, u64 size) {} extern int walk_memory_range(unsigned long start_pfn, unsigned long end_pfn, void *arg, int (*func)(struct memory_block *, void *)); -extern int mem_online_node(int nid); extern int add_memory(int nid, u64 start, u64 size); extern int arch_add_memory(int nid, u64 start, u64 size); extern int offline_pages(unsigned long start_pfn, unsigned long nr_pages); diff --git a/kernel/cpu.c b/kernel/cpu.c index 63aa50d7ce1e..973d034acf84 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -437,11 +437,6 @@ int cpu_up(unsigned int cpu) { int err = 0; -#ifdef CONFIG_MEMORY_HOTPLUG - int nid; - pg_data_t *pgdat; -#endif - if (!cpu_possible(cpu)) { printk(KERN_ERR "can't online cpu %d because it is not " "configured as may-hotadd at boot time\n", cpu); @@ -452,27 +447,9 @@ int cpu_up(unsigned int cpu) return -EINVAL; } -#ifdef CONFIG_MEMORY_HOTPLUG - nid = cpu_to_node(cpu); - if (!node_online(nid)) { - err = mem_online_node(nid); - if (err) - return err; - } - - pgdat = NODE_DATA(nid); - if (!pgdat) { - printk(KERN_ERR - "Can't online cpu %d due to NULL pgdat\n", cpu); - return -ENOMEM; - } - - if (pgdat->node_zonelists->_zonerefs->zone == NULL) { - mutex_lock(&zonelists_mutex); - build_all_zonelists(NULL, NULL); - mutex_unlock(&zonelists_mutex); - } -#endif + err = try_online_node(cpu_to_node(cpu)); + if (err) + return err; cpu_maps_update_begin(); diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 5118028468eb..8285346be663 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1043,17 +1043,23 @@ static void rollback_node_hotadd(int nid, pg_data_t *pgdat) } -/* +/** + * try_online_node - online a node if offlined + * * called by cpu_up() to online a node without onlined memory. */ -int mem_online_node(int nid) +int try_online_node(int nid) { pg_data_t *pgdat; int ret; + if (node_online(nid)) + return 0; + lock_memory_hotplug(); pgdat = hotadd_new_pgdat(nid, 0); if (!pgdat) { + pr_err("Cannot online node %d due to NULL pgdat\n", nid); ret = -ENOMEM; goto out; } @@ -1061,6 +1067,12 @@ int mem_online_node(int nid) ret = register_one_node(nid); BUG_ON(ret); + if (pgdat->node_zonelists->_zonerefs->zone == NULL) { + mutex_lock(&zonelists_mutex); + build_all_zonelists(NULL, NULL); + mutex_unlock(&zonelists_mutex); + } + out: unlock_memory_hotplug(); return ret; |