#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
+#ifndef CONFIG_HAVE_LEGACY_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;
+extern const unsigned long *pcpu_unit_offsets;
+
+struct pcpu_group_info {
+ int nr_units; /* aligned # of units */
+ unsigned long base_offset; /* base address offset */
+ unsigned int *cpu_map; /* unit->cpu map, empty
+ * entries contain NR_CPUS */
+};
+
+struct pcpu_alloc_info {
+ size_t static_size;
+ size_t reserved_size;
+ size_t dyn_size;
+ size_t unit_size;
+ size_t atom_size;
+ size_t alloc_size;
+ size_t __ai_size; /* internal, don't use */
+ int nr_groups; /* 0 if grouping unnecessary */
+ struct pcpu_group_info groups[];
+};
+
+enum pcpu_fc {
+ PCPU_FC_AUTO,
+ PCPU_FC_EMBED,
+ PCPU_FC_PAGE,
+
+ PCPU_FC_NR,
+};
+extern const char *pcpu_fc_names[PCPU_FC_NR];
+
+extern enum pcpu_fc pcpu_chosen_fc;
+
+typedef void * (*pcpu_fc_alloc_fn_t)(unsigned int cpu, size_t size,
+ size_t align);
+typedef void (*pcpu_fc_free_fn_t)(void *ptr, size_t size);
+typedef void (*pcpu_fc_populate_pte_fn_t)(unsigned long addr);
+typedef int (pcpu_fc_cpu_distance_fn_t)(unsigned int from, unsigned int to);
+
+extern struct pcpu_alloc_info * __init pcpu_alloc_alloc_info(int nr_groups,
+ int nr_units);
+extern void __init pcpu_free_alloc_info(struct pcpu_alloc_info *ai);
+
+extern struct pcpu_alloc_info * __init pcpu_build_alloc_info(
+ size_t reserved_size, ssize_t dyn_size,
+ size_t atom_size,
+ pcpu_fc_cpu_distance_fn_t cpu_distance_fn);
+
+extern int __init pcpu_setup_first_chunk(const struct pcpu_alloc_info *ai,
+ void *base_addr);
+
+#ifdef CONFIG_NEED_PER_CPU_EMBED_FIRST_CHUNK
+extern int __init pcpu_embed_first_chunk(size_t reserved_size, ssize_t dyn_size,
+ size_t atom_size,
+ pcpu_fc_cpu_distance_fn_t cpu_distance_fn,
+ pcpu_fc_alloc_fn_t alloc_fn,
+ pcpu_fc_free_fn_t free_fn);
+#endif
+
+#ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK
+extern int __init pcpu_page_first_chunk(size_t reserved_size,
+ pcpu_fc_alloc_fn_t alloc_fn,
+ pcpu_fc_free_fn_t free_fn,
+ pcpu_fc_populate_pte_fn_t populate_pte_fn);
+#endif
+
+/*
+ * 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_LEGACY_PER_CPU_AREA */
+
struct percpu_data {
- void *ptrs[NR_CPUS];
+ 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)]; \
+/* pointer disguising messes up the kmemleak objects tracking */
+#ifndef CONFIG_DEBUG_KMEMLEAK
+#define __percpu_disguise(pdata) (struct percpu_data *)~(unsigned long)(pdata)
+#else
+#define __percpu_disguise(pdata) (struct percpu_data *)(pdata)
+#endif
+
+#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_LEGACY_PER_CPU_AREA */
+
+extern void *__alloc_percpu(size_t size, size_t align);
+extern void free_percpu(void *__pdata);
+
+#ifndef CONFIG_HAVE_SETUP_PER_CPU_AREA
+extern void __init setup_per_cpu_areas(void);
+#endif
#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)
+{
+ /*
+ * 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(void *p)
{
- void *ret = kmalloc(size, GFP_KERNEL);
- if (ret)
- memset(ret, 0, size);
- return ret;
+ kfree(p);
}
-static inline void free_percpu(const void *ptr)
-{
- kfree(ptr);
+
+static inline void __init setup_per_cpu_areas(void) { }
+
+static inline void *pcpu_lpage_remapped(void *kaddr)
+{
+ return NULL;
}
#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 */