1 files changed, 149 insertions, 0 deletions
diff --git a/include/linux/percpu.h b/include/linux/percpu.h
new file mode 100644
index 000000000..68fac2e7c
--- /dev/null
+++ b/include/linux/percpu.h
@@ -0,0 +1,149 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __LINUX_PERCPU_H
+#define __LINUX_PERCPU_H
+
+#include <linux/mmdebug.h>
+#include <linux/preempt.h>
+#include <linux/smp.h>
+#include <linux/cpumask.h>
+#include <linux/pfn.h>
+#include <linux/init.h>
+#include <linux/cleanup.h>
+
+#include <asm/percpu.h>
+
+/* 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
+
+/* minimum unit size, also is the maximum supported allocation size */
+#define PCPU_MIN_UNIT_SIZE		PFN_ALIGN(32 << 10)
+
+/* minimum allocation size and shift in bytes */
+#define PCPU_MIN_ALLOC_SHIFT		2
+#define PCPU_MIN_ALLOC_SIZE		(1 << PCPU_MIN_ALLOC_SHIFT)
+
+/*
+ * The PCPU_BITMAP_BLOCK_SIZE must be the same size as PAGE_SIZE as the
+ * updating of hints is used to manage the nr_empty_pop_pages in both
+ * the chunk and globally.
+ */
+#define PCPU_BITMAP_BLOCK_SIZE		PAGE_SIZE
+#define PCPU_BITMAP_BLOCK_BITS		(PCPU_BITMAP_BLOCK_SIZE >>	\
+					 PCPU_MIN_ALLOC_SHIFT)
+
+#ifdef CONFIG_RANDOM_KMALLOC_CACHES
+#define PERCPU_DYNAMIC_SIZE_SHIFT      12
+#else
+#define PERCPU_DYNAMIC_SIZE_SHIFT      10
+#endif
+
+/*
+ * Percpu allocator can serve percpu allocations before slab is
+ * initialized which allows slab to depend on the percpu allocator.
+ * The following parameter decide how much resource to preallocate
+ * for this.  Keep PERCPU_DYNAMIC_RESERVE equal to or larger than
+ * PERCPU_DYNAMIC_EARLY_SIZE.
+ */
+#define PERCPU_DYNAMIC_EARLY_SIZE	(20 << PERCPU_DYNAMIC_SIZE_SHIFT)
+
+/*
+ * 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		(28 << PERCPU_DYNAMIC_SIZE_SHIFT)
+#else
+#define PERCPU_DYNAMIC_RESERVE		(20 << PERCPU_DYNAMIC_SIZE_SHIFT)
+#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 * const pcpu_fc_names[PCPU_FC_NR];
+
+extern enum pcpu_fc pcpu_chosen_fc;
+
+typedef int (pcpu_fc_cpu_to_node_fn_t)(int cpu);
+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 void __init pcpu_setup_first_chunk(const struct pcpu_alloc_info *ai,
+					 void *base_addr);
+
+extern int __init pcpu_embed_first_chunk(size_t reserved_size, size_t dyn_size,
+				size_t atom_size,
+				pcpu_fc_cpu_distance_fn_t cpu_distance_fn,
+				pcpu_fc_cpu_to_node_fn_t cpu_to_nd_fn);
+
+#ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK
+void __init pcpu_populate_pte(unsigned long addr);
+extern int __init pcpu_page_first_chunk(size_t reserved_size,
+				pcpu_fc_cpu_to_node_fn_t cpu_to_nd_fn);
+#endif
+
+extern void __percpu *__alloc_reserved_percpu(size_t size, size_t align) __alloc_size(1);
+extern bool __is_kernel_percpu_address(unsigned long addr, unsigned long *can_addr);
+extern bool is_kernel_percpu_address(unsigned long addr);
+
+#if !defined(CONFIG_SMP) || !defined(CONFIG_HAVE_SETUP_PER_CPU_AREA)
+extern void __init setup_per_cpu_areas(void);
+#endif
+
+extern void __percpu *__alloc_percpu_gfp(size_t size, size_t align, gfp_t gfp) __alloc_size(1);
+extern void __percpu *__alloc_percpu(size_t size, size_t align) __alloc_size(1);
+extern void free_percpu(void __percpu *__pdata);
+
+DEFINE_FREE(free_percpu, void __percpu *, free_percpu(_T))
+
+extern phys_addr_t per_cpu_ptr_to_phys(void *addr);
+
+#define alloc_percpu_gfp(type, gfp)					\
+	(typeof(type) __percpu *)__alloc_percpu_gfp(sizeof(type),	\
+						__alignof__(type), gfp)
+#define alloc_percpu(type)						\
+	(typeof(type) __percpu *)__alloc_percpu(sizeof(type),		\
+						__alignof__(type))
+
+extern unsigned long pcpu_nr_pages(void);
+
+#endif /* __LINUX_PERCPU_H */