util/mr_cache: Add framework for memory registration cache

This is derived from work by Dmitry Gladkov, which was based on
the registration cache in the gni provider.

The interface for the cache is comprised of initialization and
cleanup routines, plus two calls: search and delete.  Search
will first search the cache for a region that contains the
provided input region.  If no existing region is found, the
new region is added to the cache.  Delete marks that the user
is done with the region.  Every search call should be paired
with a delete call.

If caching is enabled, the freeing of a delete region will be
deferred until it is both no longer being accessed, and is the
region that has the oldest access time.

Signed-off-by: Sean Hefty <[email protected]>
Signed-off-by: Dmitry Gladkov <[email protected]>

Makefile.am

@@ -61,7 +61,8 @@ common_srcs =				\
 	prov/util/src/util_mr_map.c	\
 	prov/util/src/util_ns.c		\
 	prov/util/src/util_shm.c	\
-	prov/util/src/util_mem_monitor.c
+	prov/util/src/util_mem_monitor.c\
+	prov/util/src/util_mr_cache.c
 
 if MACOS
 common_srcs += src/unix/osd.c

include/fi_iov.h

@@ -36,6 +36,7 @@
 
 #include "config.h"
 
+#include <stdbool.h>
 #include <stdlib.h>
 #include <string.h>
 #include <sys/uio.h>
@@ -82,6 +83,30 @@ ofi_copy_from_iov(void *buf, uint64_t bufsize,
 				OFI_COPY_IOV_TO_BUF);
 }
 
+static inline void *
+ofi_iov_end(const struct iovec *iov)
+{
+	return ((char *) iov->iov_base) + iov->iov_len;
+}
+
+static inline bool
+ofi_iov_left(const struct iovec *iov1, const struct iovec *iov2)
+{
+	return ofi_iov_end(iov1) < iov2->iov_base;
+}
+
+static inline bool
+ofi_iov_right(const struct iovec *iov1, const struct iovec *iov2)
+{
+	return iov1->iov_base > ofi_iov_end(iov2);
+}
+
+static inline bool
+ofi_iov_within(const struct iovec *iov1, const struct iovec *iov2)
+{
+	return (iov1->iov_base >= iov2->iov_base) &&
+	       (ofi_iov_end(iov1) <= ofi_iov_end(iov2));
+}
 
 #endif /* IOV_H */
 

include/ofi_mr.h

@@ -38,11 +38,14 @@
 #endif /* HAVE_CONFIG_H */
 
 #include <inttypes.h>
+#include <stdbool.h>
 
 #include <fi.h>
 #include <fi_atom.h>
 #include <fi_lock.h>
 #include <fi_list.h>
+#include <rbtree.h>
+
 
 #define OFI_MR_BASIC_MAP (FI_MR_ALLOCATED | FI_MR_PROV_KEY | FI_MR_VIRT_ADDR)
 
@@ -74,6 +77,7 @@ static inline uint64_t ofi_mr_get_prov_mode(uint32_t version,
 	}
 }
 
+
 /*
  * Memory notifier - Report memory mapping changes to address ranges
  */
@@ -113,9 +117,10 @@ int ofi_monitor_subscribe(struct ofi_notification_queue *nq,
 			  void *addr, size_t len,
 			  struct ofi_subscription *subscription);
 void ofi_monitor_unsubscribe(void *addr, size_t len,
-			      struct ofi_subscription *subscription);
+			     struct ofi_subscription *subscription);
 struct ofi_subscription *ofi_monitor_get_event(struct ofi_notification_queue *nq);
 
+
 /*
  * MR map
  */
@@ -141,4 +146,51 @@ int ofi_mr_map_verify(struct ofi_mr_map *map, uintptr_t *io_addr,
 		      size_t len, uint64_t key, uint64_t access,
 		      void **context);
 
+
+/*
+ * Memory registration cache
+ */
+
+struct ofi_mr_entry {
+	struct iovec			iov;
+	uint64_t			access;	/* TODO */
+	unsigned int			cached:1;
+	unsigned int			subscribed:1;
+	int				use_cnt;
+	struct dlist_entry		lru_entry;
+	struct ofi_subscription		subscription;
+	uint8_t				data[];
+};
+
+struct ofi_mr_cache {
+	struct util_domain		*domain;
+	struct ofi_notification_queue	nq;
+	size_t				size;
+	size_t				entry_data_size;
+
+	RbtHandle			mr_tree;
+	struct dlist_entry		lru_list;
+
+	uint64_t			cached_cnt;
+	uint64_t			search_cnt;
+	uint64_t			delete_cnt;
+	uint64_t			hit_cnt;
+
+	int				(*add_region)(struct ofi_mr_cache *cache,
+						      struct ofi_mr_entry *entry);
+	void				(*delete_region)(struct ofi_mr_cache *cache,
+							 struct ofi_mr_entry *entry);
+};
+
+int ofi_mr_cache_init(struct util_domain *domain, struct ofi_mem_monitor *monitor,
+		      struct ofi_mr_cache *cache);
+void ofi_mr_cache_cleanup(struct ofi_mr_cache *cache);
+
+/* Caller must provide locking around calls */
+bool ofi_mr_cache_flush(struct ofi_mr_cache *cache);
+int ofi_mr_cache_search(struct ofi_mr_cache *cache, const struct fi_mr_attr *attr,
+			struct ofi_mr_entry **entry);
+void ofi_mr_cache_delete(struct ofi_mr_cache *cache, struct ofi_mr_entry *entry);
+
+
 #endif /* _OFI_MR_H_ */