percpu: migrate percpu data structures to internal header

Migrates pcpu_chunk definition and a few percpu static variables to an
internal header file from mm/percpu.c. These will be used with debugfs
to expose statistics about percpu memory improving visibility regarding
allocations and fragmentation.

Signed-off-by: Dennis Zhou <dennisz@fb.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

1 files changed, 33 insertions, 0 deletions

diff --git a/mm/percpu-internal.h b/mm/percpu-internal.h
new file mode 100644
index 000000000000..68bf18522a6d
--- /dev/null
+++ b/mm/percpu-internal.h
@@ -0,0 +1,33 @@
+#ifndef _MM_PERCPU_INTERNAL_H
+#define _MM_PERCPU_INTERNAL_H
+
+#include <linux/types.h>
+#include <linux/percpu.h>
+
+struct pcpu_chunk {
+        struct list_head        list;           /* linked to pcpu_slot lists */
+        int                     free_size;      /* free bytes in the chunk */
+        int                     contig_hint;    /* max contiguous size hint */
+        void                    *base_addr;     /* base address of this chunk */
+
+        int                     map_used;       /* # of map entries used before the sentry */
+        int                     map_alloc;      /* # of map entries allocated */
+        int                     *map;           /* allocation map */
+        struct list_head        map_extend_list;/* on pcpu_map_extend_chunks */
+
+        void                    *data;          /* chunk data */
+        int                     first_free;     /* no free below this */
+        bool                    immutable;      /* no [de]population allowed */
+        int                     nr_populated;   /* # of populated pages */
+        unsigned long           populated[];    /* populated bitmap */
+};
+
+extern spinlock_t pcpu_lock;
+
+extern struct list_head *pcpu_slot;
+extern int pcpu_nr_slots;
+
+extern struct pcpu_chunk *pcpu_first_chunk;
+extern struct pcpu_chunk *pcpu_reserved_chunk;
+
+#endif