Commit cf450c0d authored by Ben Walker's avatar Ben Walker Committed by Tomasz Zawadzki
Browse files

env: Add spdk_mem_reserve 



The spdk_mem_reserve() function reserves a memory region in SPDK's
memory maps. This pre-allocates all of the required data structures
to hold memory address translations for that region without actually
populating the region.

After a region is reserved, calls to spdk_mem_register() for
addresses in that range will not require any internal memory
allocations. This is useful when overlaying a custom memory allocator
on top of SPDK's hugepage memory, such as tcmalloc.

Signed-off-by: default avatarBen Walker <benjamin.walker@intel.com>
Change-Id: Ia4e8a770e8b5c956814aa90e9119013356dfab46
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/2511


Community-CI: Mellanox Build Bot
Community-CI: Broadcom CI
Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: default avatarTomasz Zawadzki <tomasz.zawadzki@intel.com>
Reviewed-by: default avatarJim Harris <james.r.harris@intel.com>
Reviewed-by: default avatarAleksey Marchuk <alexeymar@mellanox.com>
parent 8668141b

include/spdk/env.h

+14 −0
Original line number Diff line number Diff line
@@ -1248,6 +1248,20 @@ int spdk_mem_register(void *vaddr, size_t len); 
 */

int spdk_mem_unregister(void *vaddr, size_t len);



/**

 * Reserve the address space specified in all memory maps.

 *

 * This pre-allocates the necessary space in the memory maps such that

 * future calls to spdk_mem_register() on that region require no

 * internal memory allocations.

 *

 * \param vaddr Virtual address to reserve

 * \param len Length in bytes of vaddr

 *

 * \return 0 on success, negated errno on failure.

 */

int spdk_mem_reserve(void *vaddr, size_t len);



#ifdef __cplusplus

}

#endif

lib/env_dpdk/memory.c

+51 −0
Original line number Diff line number Diff line
@@ -509,6 +509,57 @@ spdk_mem_unregister(void *vaddr, size_t len) 
	return 0;

}



int

spdk_mem_reserve(void *vaddr, size_t len)

{

	struct spdk_mem_map *map;

	void *seg_vaddr;

	size_t seg_len;

	uint64_t reg;



	if ((uintptr_t)vaddr & ~MASK_256TB) {

		DEBUG_PRINT("invalid usermode virtual address %p\n", vaddr);

		return -EINVAL;

	}



	if (((uintptr_t)vaddr & MASK_2MB) || (len & MASK_2MB)) {

		DEBUG_PRINT("invalid %s parameters, vaddr=%p len=%ju\n",

			    __func__, vaddr, len);

		return -EINVAL;

	}



	if (len == 0) {

		return 0;

	}



	pthread_mutex_lock(&g_spdk_mem_map_mutex);



	/* Check if any part of this range is already registered */

	seg_vaddr = vaddr;

	seg_len = len;

	while (seg_len > 0) {

		reg = spdk_mem_map_translate(g_mem_reg_map, (uint64_t)seg_vaddr, NULL);

		if (reg & REG_MAP_REGISTERED) {

			pthread_mutex_unlock(&g_spdk_mem_map_mutex);

			return -EBUSY;

		}

		seg_vaddr += VALUE_2MB;

		seg_len -= VALUE_2MB;

	}



	/* Simply set the translation to the memory map's default. This allocates the space in the

	 * map but does not provide a valid translation. */

	spdk_mem_map_set_translation(g_mem_reg_map, (uint64_t)vaddr, len,

				     g_mem_reg_map->default_translation);



	TAILQ_FOREACH(map, &g_spdk_mem_maps, tailq) {

		spdk_mem_map_set_translation(map, (uint64_t)vaddr, len, map->default_translation);

	}



	pthread_mutex_unlock(&g_spdk_mem_map_mutex);

	return 0;

}



static struct map_1gb *

spdk_mem_map_get_map_1gb(struct spdk_mem_map *map, uint64_t vfn_2mb)

{