From f02c696800886382198df897b30bb796b46a8dae Mon Sep 17 00:00:00 2001 From: Andrew Morton Date: Mon, 29 Apr 2013 15:08:04 -0700 Subject: include/linux/memory.h: implement register_hotmemory_notifier() When CONFIG_MEMORY_HOTPLUG=n, we don't want the memory-hotplug notifier handlers to be included in the .o files, for space reasons. The existing hotplug_memory_notifier() tries to handle this but testing with gcc-4.4.4 shows that it doesn't work - the hotplug functions are still present in the .o files. So implement a new register_hotmemory_notifier() which is a copy of register_hotcpu_notifier(), and which actually works as desired. hotplug_memory_notifier() and register_memory_notifier() callsites should be converted to use this new register_hotmemory_notifier(). While we're there, let's repair the existing hotplug_memory_notifier(): it simply stomps on the register_memory_notifier() return value, so well-behaved code cannot check for errors. Apparently non of the existing callers were well-behaved :( Cc: Andrew Shewmaker Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/memory.h | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) (limited to 'include/linux/memory.h') diff --git a/include/linux/memory.h b/include/linux/memory.h index 45e93b468878..0ff6598ee62f 100644 --- a/include/linux/memory.h +++ b/include/linux/memory.h @@ -18,6 +18,7 @@ #include #include #include +#include #define MIN_MEMORY_BLOCK_SIZE (1UL << SECTION_SIZE_BITS) @@ -127,13 +128,18 @@ enum mem_add_context { BOOT, HOTPLUG }; #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */ #ifdef CONFIG_MEMORY_HOTPLUG -#define hotplug_memory_notifier(fn, pri) { \ +#define hotplug_memory_notifier(fn, pri) ({ \ static __meminitdata struct notifier_block fn##_mem_nb =\ - { .notifier_call = fn, .priority = pri }; \ + { .notifier_call = fn, .priority = pri };\ register_memory_notifier(&fn##_mem_nb); \ -} +}) +#define register_hotmemory_notifier(nb) register_memory_notifier(nb) +#define unregister_hotmemory_notifier(nb) unregister_memory_notifier(nb) #else -#define hotplug_memory_notifier(fn, pri) do { } while (0) +#define hotplug_memory_notifier(fn, pri) (0) +/* These aren't inline functions due to a GCC bug. */ +#define register_hotmemory_notifier(nb) ({ (void)(nb); 0; }) +#define unregister_hotmemory_notifier(nb) ({ (void)(nb); }) #endif /* -- cgit v1.2.3 From 4edd7ceff0662afde195da6f6c43e7cbe1ed2dc4 Mon Sep 17 00:00:00 2001 From: David Rientjes Date: Mon, 29 Apr 2013 15:08:22 -0700 Subject: mm, hotplug: avoid compiling memory hotremove functions when disabled __remove_pages() is only necessary for CONFIG_MEMORY_HOTREMOVE. PowerPC pseries will return -EOPNOTSUPP if unsupported. Adding an #ifdef causes several other functions it depends on to also become unnecessary, which saves in .text when disabled (it's disabled in most defconfigs besides powerpc, including x86). remove_memory_block() becomes static since it is not referenced outside of drivers/base/memory.c. Build tested on x86 and powerpc with CONFIG_MEMORY_HOTREMOVE both enabled and disabled. Signed-off-by: David Rientjes Acked-by: Toshi Kani Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Greg Kroah-Hartman Cc: Wen Congyang Cc: Tang Chen Cc: Yasuaki Ishimatsu Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/memory.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'include/linux/memory.h') diff --git a/include/linux/memory.h b/include/linux/memory.h index 0ff6598ee62f..73817af8b480 100644 --- a/include/linux/memory.h +++ b/include/linux/memory.h @@ -115,9 +115,10 @@ extern void unregister_memory_notifier(struct notifier_block *nb); extern int register_memory_isolate_notifier(struct notifier_block *nb); extern void unregister_memory_isolate_notifier(struct notifier_block *nb); extern int register_new_memory(int, struct mem_section *); +#ifdef CONFIG_MEMORY_HOTREMOVE extern int unregister_memory_section(struct mem_section *); +#endif extern int memory_dev_init(void); -extern int remove_memory_block(unsigned long, struct mem_section *, int); extern int memory_notify(unsigned long val, void *v); extern int memory_isolate_notify(unsigned long val, void *v); extern struct memory_block *find_memory_block_hinted(struct mem_section *, -- cgit v1.2.3 From ace6128d603d3f15238baba104d0b37ccf0b6c07 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Vincent=20Stehl=C3=A9?= Date: Tue, 30 Apr 2013 15:26:45 -0700 Subject: memory hotplug: fix warnings MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Fix the following compilation warnings: mm/slab.c: In function `kmem_cache_init_late': mm/slab.c:1778:2: warning: statement with no effect [-Wunused-value] mm/page_cgroup.c: In function `page_cgroup_init': mm/page_cgroup.c:305:2: warning: statement with no effect [-Wunused-value] Signed-off-by: Vincent Stehlé Cc: David Rientjes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/memory.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/memory.h') diff --git a/include/linux/memory.h b/include/linux/memory.h index 73817af8b480..85c31a8e2904 100644 --- a/include/linux/memory.h +++ b/include/linux/memory.h @@ -137,7 +137,7 @@ enum mem_add_context { BOOT, HOTPLUG }; #define register_hotmemory_notifier(nb) register_memory_notifier(nb) #define unregister_hotmemory_notifier(nb) unregister_memory_notifier(nb) #else -#define hotplug_memory_notifier(fn, pri) (0) +#define hotplug_memory_notifier(fn, pri) ({ 0; }) /* These aren't inline functions due to a GCC bug. */ #define register_hotmemory_notifier(nb) ({ (void)(nb); 0; }) #define unregister_hotmemory_notifier(nb) ({ (void)(nb); }) -- cgit v1.2.3