diff mbox

[API-NEXT,PATCHv9,07/15] api: shm: add flags to shm_reserve and function to find external mem

Message ID 1480004553-46760-8-git-send-email-christophe.milard@linaro.org
State Accepted
Commit 6d78d33df6d33ebe1b933383c4858df5e9f7f33b
Headers show

Commit Message

Christophe Milard Nov. 24, 2016, 4:22 p.m. UTC
The ODP_SHM_SINGLE_VA flag is created: when set (at odp_shm_reserve()),
this flag guarantees that all ODP threads sharing this memory
block will see the block at the same address (regadless of ODP
thread type -pthread vs process- or fork time)

The flag ODP_SHM_EXPORT is added: when passed at odp_shm_reserve() time
the memory block becomes visible to other ODP instances.
The function odp_shm_import() is added: this function enables to
reserve block of memories exported by other ODP instances (using the
ODP_SHM_EXPORT flag).

Signed-off-by: Christophe Milard <christophe.milard@linaro.org>

---
 include/odp/api/spec/shared_memory.h | 46 ++++++++++++++++++++++++++++++++----
 1 file changed, 41 insertions(+), 5 deletions(-)

-- 
2.7.4
diff mbox

Patch

diff --git a/include/odp/api/spec/shared_memory.h b/include/odp/api/spec/shared_memory.h
index 8c76807..885751d 100644
--- a/include/odp/api/spec/shared_memory.h
+++ b/include/odp/api/spec/shared_memory.h
@@ -14,6 +14,7 @@ 
 #ifndef ODP_API_SHARED_MEMORY_H_
 #define ODP_API_SHARED_MEMORY_H_
 #include <odp/visibility_begin.h>
+#include <odp/api/init.h>
 
 #ifdef __cplusplus
 extern "C" {
@@ -43,12 +44,25 @@  extern "C" {
 #define ODP_SHM_NAME_LEN 32
 
 /*
- * Shared memory flags
+ * Shared memory flags:
  */
-
-/* Share level */
-#define ODP_SHM_SW_ONLY 0x1 /**< Application SW only, no HW access */
-#define ODP_SHM_PROC    0x2 /**< Share with external processes */
+#define ODP_SHM_SW_ONLY		0x1 /**< Application SW only, no HW access   */
+#define ODP_SHM_PROC		0x2 /**< Share with external processes       */
+/**
+ * Single virtual address
+ *
+ * When set, this flag guarantees that all ODP threads sharing this
+ * memory block will see the block at the same address - regardless
+ * of ODP thread type (e.g. pthread vs. process (or fork process time)).
+ */
+#define ODP_SHM_SINGLE_VA	0x4
+/**
+ * Export memory
+ *
+ * When set, the memory block becomes visible to other ODP instances
+ * through odp_shm_import().
+ */
+#define ODP_SHM_EXPORT		0x08
 
 /**
  * Shared memory block info
@@ -135,6 +149,28 @@  int odp_shm_free(odp_shm_t shm);
  */
 odp_shm_t odp_shm_lookup(const char *name);
 
+/**
+ * Import a block of shared memory, exported by another ODP instance
+ *
+ * This call creates a new handle for accessing a shared memory block created
+ * (with ODP_SHM_EXPORT flag) by another ODP instance. An instance may have
+ * only a single handle to the same block. Application must not access the
+ * block after freeing the handle. When an imported handle is freed, only
+ * the calling instance is affected. The exported block may be freed only
+ * after all other instances have stopped accessing the block.
+ *
+ * @param remote_name  Name of the block, in the remote ODP instance
+ * @param odp_inst     Remote ODP instance, as returned by odp_init_global()
+ * @param local_name   Name given to the block, in the local ODP instance
+ *		       May be NULL, if the application doesn't need a name
+ *		       (for a lookup).
+ *
+ * @return A handle to access a block exported by another ODP instance.
+ * @retval ODP_SHM_INVALID on failure
+ */
+odp_shm_t odp_shm_import(const char *remote_name,
+			 odp_instance_t odp_inst,
+			 const char *local_name);
 
 /**
  * Shared memory block address