alloc_percpu: add align argument to __alloc_percpu.

[safe/jmp/linux-2.6] / include / linux / percpu.h

diff --git a/include/linux/percpu.h b/include/linux/percpu.h
index 5451eb1..1fdaee9 100644 (file)
--- a/include/linux/percpu.h
+++ b/include/linux/percpu.h
@@ -1,61 +1,127 @@
 #ifndef __LINUX_PERCPU_H
 #define __LINUX_PERCPU_H
-#include <linux/spinlock.h> /* For preempt_disable() */
+
+#include <linux/preempt.h>
 #include <linux/slab.h> /* For kmalloc() */
 #include <linux/smp.h>
-#include <linux/string.h> /* For memset() */
+#include <linux/cpumask.h>
+
 #include <asm/percpu.h>
 
+#ifndef PER_CPU_BASE_SECTION
+#ifdef CONFIG_SMP
+#define PER_CPU_BASE_SECTION ".data.percpu"
+#else
+#define PER_CPU_BASE_SECTION ".data"
+#endif
+#endif
+
+#ifdef CONFIG_SMP
+
+#ifdef MODULE
+#define PER_CPU_SHARED_ALIGNED_SECTION ""
+#else
+#define PER_CPU_SHARED_ALIGNED_SECTION ".shared_aligned"
+#endif
+#define PER_CPU_FIRST_SECTION ".first"
+
+#else
+
+#define PER_CPU_SHARED_ALIGNED_SECTION ""
+#define PER_CPU_FIRST_SECTION ""
+
+#endif
+
+#define DEFINE_PER_CPU_SECTION(type, name, section)                    \
+       __attribute__((__section__(PER_CPU_BASE_SECTION section)))      \
+       PER_CPU_ATTRIBUTES __typeof__(type) per_cpu__##name
+
+#define DEFINE_PER_CPU(type, name)                                     \
+       DEFINE_PER_CPU_SECTION(type, name, "")
+
+#define DEFINE_PER_CPU_SHARED_ALIGNED(type, name)                      \
+       DEFINE_PER_CPU_SECTION(type, name, PER_CPU_SHARED_ALIGNED_SECTION) \
+       ____cacheline_aligned_in_smp
+
+#define DEFINE_PER_CPU_PAGE_ALIGNED(type, name)                                \
+       DEFINE_PER_CPU_SECTION(type, name, ".page_aligned")
+
+#define DEFINE_PER_CPU_FIRST(type, name)                               \
+       DEFINE_PER_CPU_SECTION(type, name, PER_CPU_FIRST_SECTION)
+
+#define EXPORT_PER_CPU_SYMBOL(var) EXPORT_SYMBOL(per_cpu__##var)
+#define EXPORT_PER_CPU_SYMBOL_GPL(var) EXPORT_SYMBOL_GPL(per_cpu__##var)
+
 /* Enough to cover all DEFINE_PER_CPUs in kernel, including modules. */
 #ifndef PERCPU_ENOUGH_ROOM
-#define PERCPU_ENOUGH_ROOM 32768
+#ifdef CONFIG_MODULES
+#define PERCPU_MODULE_RESERVE  8192
+#else
+#define PERCPU_MODULE_RESERVE  0
 #endif
 
-/* Must be an lvalue. */
-#define get_cpu_var(var) (*({ preempt_disable(); &__get_cpu_var(var); }))
+#define PERCPU_ENOUGH_ROOM                                             \
+       (__per_cpu_end - __per_cpu_start + PERCPU_MODULE_RESERVE)
+#endif /* PERCPU_ENOUGH_ROOM */
+
+/*
+ * Must be an lvalue. Since @var must be a simple identifier,
+ * we force a syntax error here if it isn't.
+ */
+#define get_cpu_var(var) (*({                          \
+       extern int simple_identifier_##var(void);       \
+       preempt_disable();                              \
+       &__get_cpu_var(var); }))
 #define put_cpu_var(var) preempt_enable()
 
 #ifdef CONFIG_SMP
 
 struct percpu_data {
-       void *ptrs[NR_CPUS];
-       void *blkp;
+       void *ptrs[1];
 };
 
-/* 
- * Use this to get to a cpu's version of the per-cpu object allocated using
- * alloc_percpu.  Non-atomic access to the current CPU's version should
- * probably be combined with get_cpu()/put_cpu().
- */ 
-#define per_cpu_ptr(ptr, cpu)                   \
-({                                              \
-        struct percpu_data *__p = (struct percpu_data *)~(unsigned long)(ptr); \
-        (__typeof__(ptr))__p->ptrs[(cpu)];     \
-})
+#define __percpu_disguise(pdata) (struct percpu_data *)~(unsigned long)(pdata)
 
-extern void *__alloc_percpu(size_t size, size_t align);
-extern void free_percpu(const void *);
+extern void *__percpu_alloc_mask(size_t size, gfp_t gfp, cpumask_t *mask);
+extern void percpu_free(void *__pdata);
 
 #else /* CONFIG_SMP */
 
-#define per_cpu_ptr(ptr, cpu) (ptr)
+#define per_cpu_ptr(ptr, cpu) ({ (void)(cpu); (ptr); })
 
-static inline void *__alloc_percpu(size_t size, size_t align)
+static __always_inline void *__percpu_alloc_mask(size_t size, gfp_t gfp, cpumask_t *mask)
 {
-       void *ret = kmalloc(size, GFP_KERNEL);
-       if (ret)
-               memset(ret, 0, size);
-       return ret;
+       return kzalloc(size, gfp);
 }
-static inline void free_percpu(const void *ptr)
-{      
-       kfree(ptr);
+
+static inline void percpu_free(void *__pdata)
+{
+       kfree(__pdata);
 }
 
 #endif /* CONFIG_SMP */
 
-/* Simple wrapper for the common case: zeros memory. */
-#define alloc_percpu(type) \
-       ((type *)(__alloc_percpu(sizeof(type), __alignof__(type))))
+#define percpu_alloc_mask(size, gfp, mask) \
+       __percpu_alloc_mask((size), (gfp), &(mask))
+
+#define percpu_alloc(size, gfp) percpu_alloc_mask((size), (gfp), cpu_online_map)
+
+/* (legacy) interface for use without CPU hotplug handling */
+
+#define __alloc_percpu(size, align)    percpu_alloc_mask((size), GFP_KERNEL, \
+                                                 cpu_possible_map)
+#define alloc_percpu(type)     (type *)__alloc_percpu(sizeof(type), \
+                                                      __alignof__(type))
+#define free_percpu(ptr)       percpu_free((ptr))
+/*
+ * Use this to get to a cpu's version of the per-cpu object dynamically
+ * allocated. Non-atomic access to the current CPU's version should
+ * probably be combined with get_cpu()/put_cpu().
+ */
+#define per_cpu_ptr(ptr, cpu)                                          \
+({                                                                     \
+        struct percpu_data *__p = __percpu_disguise(ptr);              \
+        (__typeof__(ptr))__p->ptrs[(cpu)];                             \
+})
 
 #endif /* __LINUX_PERCPU_H */