fs/ceph/msgpool.h

   1 #ifndef _FS_CEPH_MSGPOOL
   2 #define _FS_CEPH_MSGPOOL
   3
   4 #include "messenger.h"
   5
   6 /*
   7  * we use memory pools for preallocating messages we may receive, to
   8  * avoid unexpected OOM conditions.
   9  */
  10 struct ceph_msgpool {
  11         spinlock_t lock;
  12         int front_len;          /* preallocated payload size */
  13         struct list_head msgs;  /* msgs in the pool; each has 1 ref */
  14         int num, min;           /* cur, min # msgs in the pool */
  15         bool blocking;
  16         wait_queue_head_t wait;
  17 };
  18
  19 extern int ceph_msgpool_init(struct ceph_msgpool *pool,
  20                              int front_len, int size, bool blocking);
  21 extern void ceph_msgpool_destroy(struct ceph_msgpool *pool);
  22 extern int ceph_msgpool_resv(struct ceph_msgpool *, int delta);
  23 extern struct ceph_msg *ceph_msgpool_get(struct ceph_msgpool *,
  24                                          int front_len);
  25 extern void ceph_msgpool_put(struct ceph_msgpool *, struct ceph_msg *);
  26
  27 #endif