#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 <linux/pfn.h>
+
#include <asm/percpu.h>
-/* Enough to cover all DEFINE_PER_CPUs in kernel, including modules. */
+/* enough to cover all DEFINE_PER_CPUs in modules */
+#ifdef CONFIG_MODULES
+#define PERCPU_MODULE_RESERVE (8 << 10)
+#else
+#define PERCPU_MODULE_RESERVE 0
+#endif
+
#ifndef PERCPU_ENOUGH_ROOM
-#define PERCPU_ENOUGH_ROOM 32768
+#define PERCPU_ENOUGH_ROOM \
+ (ALIGN(__per_cpu_end - __per_cpu_start, SMP_CACHE_BYTES) + \
+ PERCPU_MODULE_RESERVE)
#endif
-/* Must be an lvalue. */
-#define get_cpu_var(var) (*({ preempt_disable(); &__get_cpu_var(var); }))
+/*
+ * 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
+#ifdef CONFIG_HAVE_DYNAMIC_PER_CPU_AREA
+
+/* minimum unit size, also is the maximum supported allocation size */
+#define PCPU_MIN_UNIT_SIZE PFN_ALIGN(64 << 10)
+
+/*
+ * PERCPU_DYNAMIC_RESERVE indicates the amount of free area to piggy
+ * back on the first chunk for dynamic percpu allocation if arch is
+ * manually allocating and mapping it for faster access (as a part of
+ * large page mapping for example).
+ *
+ * The following values give between one and two pages of free space
+ * after typical minimal boot (2-way SMP, single disk and NIC) with
+ * both defconfig and a distro config on x86_64 and 32. More
+ * intelligent way to determine this would be nice.
+ */
+#if BITS_PER_LONG > 32
+#define PERCPU_DYNAMIC_RESERVE (20 << 10)
+#else
+#define PERCPU_DYNAMIC_RESERVE (12 << 10)
+#endif
+
+extern void *pcpu_base_addr;
+
+typedef struct page * (*pcpu_get_page_fn_t)(unsigned int cpu, int pageno);
+typedef void (*pcpu_populate_pte_fn_t)(unsigned long addr);
+
+extern size_t __init pcpu_setup_first_chunk(pcpu_get_page_fn_t get_page_fn,
+ size_t static_size, size_t reserved_size,
+ ssize_t dyn_size, ssize_t unit_size,
+ void *base_addr,
+ pcpu_populate_pte_fn_t populate_pte_fn);
+
+extern ssize_t __init pcpu_embed_first_chunk(
+ size_t static_size, size_t reserved_size,
+ ssize_t dyn_size, ssize_t unit_size);
+
+/*
+ * 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) SHIFT_PERCPU_PTR((ptr), per_cpu_offset((cpu)))
+
+extern void *__alloc_reserved_percpu(size_t size, size_t align);
+
+#else /* CONFIG_HAVE_DYNAMIC_PER_CPU_AREA */
+
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)
+
+#define per_cpu_ptr(ptr, cpu) \
+({ \
+ struct percpu_data *__p = __percpu_disguise(ptr); \
+ (__typeof__(ptr))__p->ptrs[(cpu)]; \
})
-extern void *__alloc_percpu(size_t size);
-extern void free_percpu(const void *);
+#endif /* CONFIG_HAVE_DYNAMIC_PER_CPU_AREA */
+
+extern void *__alloc_percpu(size_t size, size_t align);
+extern void free_percpu(void *__pdata);
#else /* CONFIG_SMP */
#define per_cpu_ptr(ptr, cpu) ({ (void)(cpu); (ptr); })
-static inline void *__alloc_percpu(size_t size)
+static inline void *__alloc_percpu(size_t size, size_t align)
{
- void *ret = kmalloc(size, GFP_KERNEL);
- if (ret)
- memset(ret, 0, size);
- return ret;
+ /*
+ * Can't easily make larger alignment work with kmalloc. WARN
+ * on it. Larger alignment should only be used for module
+ * percpu sections on SMP for which this path isn't used.
+ */
+ WARN_ON_ONCE(align > SMP_CACHE_BYTES);
+ return kzalloc(size, GFP_KERNEL);
}
-static inline void free_percpu(const void *ptr)
-{
- kfree(ptr);
+
+static inline void free_percpu(void *p)
+{
+ kfree(p);
}
#endif /* CONFIG_SMP */
-/* Simple wrapper for the common case: zeros memory. */
-#define alloc_percpu(type) ((type *)(__alloc_percpu(sizeof(type))))
+#define alloc_percpu(type) (type *)__alloc_percpu(sizeof(type), \
+ __alignof__(type))
+
+/*
+ * Optional methods for optimized non-lvalue per-cpu variable access.
+ *
+ * @var can be a percpu variable or a field of it and its size should
+ * equal char, int or long. percpu_read() evaluates to a lvalue and
+ * all others to void.
+ *
+ * These operations are guaranteed to be atomic w.r.t. preemption.
+ * The generic versions use plain get/put_cpu_var(). Archs are
+ * encouraged to implement single-instruction alternatives which don't
+ * require preemption protection.
+ */
+#ifndef percpu_read
+# define percpu_read(var) \
+ ({ \
+ typeof(per_cpu_var(var)) __tmp_var__; \
+ __tmp_var__ = get_cpu_var(var); \
+ put_cpu_var(var); \
+ __tmp_var__; \
+ })
+#endif
+
+#define __percpu_generic_to_op(var, val, op) \
+do { \
+ get_cpu_var(var) op val; \
+ put_cpu_var(var); \
+} while (0)
+
+#ifndef percpu_write
+# define percpu_write(var, val) __percpu_generic_to_op(var, (val), =)
+#endif
+
+#ifndef percpu_add
+# define percpu_add(var, val) __percpu_generic_to_op(var, (val), +=)
+#endif
+
+#ifndef percpu_sub
+# define percpu_sub(var, val) __percpu_generic_to_op(var, (val), -=)
+#endif
+
+#ifndef percpu_and
+# define percpu_and(var, val) __percpu_generic_to_op(var, (val), &=)
+#endif
+
+#ifndef percpu_or
+# define percpu_or(var, val) __percpu_generic_to_op(var, (val), |=)
+#endif
+
+#ifndef percpu_xor
+# define percpu_xor(var, val) __percpu_generic_to_op(var, (val), ^=)
+#endif
#endif /* __LINUX_PERCPU_H */
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff