From: Elena Agostini <eagost...@nvidia.com> Enable the possibility to make a GPU memory area accessible from the CPU.
GPU memory has to be allocated via rte_gpu_mem_alloc(). This patch allows the gpudev library to pin, through the GPU driver, a chunk of GPU memory and to return a memory pointer usable by the CPU to access the GPU memory area. Signed-off-by: Elena Agostini <eagost...@nvidia.com> --- lib/gpudev/gpudev.c | 47 +++++++++++++++++++++++++++++++++++ lib/gpudev/gpudev_driver.h | 6 +++++ lib/gpudev/rte_gpudev.h | 50 ++++++++++++++++++++++++++++++++++++++ lib/gpudev/version.map | 2 ++ 4 files changed, 105 insertions(+) diff --git a/lib/gpudev/gpudev.c b/lib/gpudev/gpudev.c index 9ae36dbae9..ca627e44b3 100644 --- a/lib/gpudev/gpudev.c +++ b/lib/gpudev/gpudev.c @@ -634,6 +634,53 @@ rte_gpu_mem_unregister(int16_t dev_id, void *ptr) return GPU_DRV_RET(dev->ops.mem_unregister(dev, ptr)); } +int +rte_gpu_mem_pin(int16_t dev_id, size_t size, void *ptr) +{ + struct rte_gpu *dev; + + dev = gpu_get_by_id(dev_id); + if (dev == NULL) { + GPU_LOG(ERR, "pin mem for invalid device ID %d", dev_id); + rte_errno = ENODEV; + return -rte_errno; + } + + if (dev->ops.mem_pin == NULL) { + GPU_LOG(ERR, "mem pinning not supported"); + rte_errno = ENOTSUP; + return -rte_errno; + } + + if (ptr == NULL || size == 0) /* dry-run */ + return 0; + + return GPU_DRV_RET(dev->ops.mem_pin(dev, size, ptr)); +} + +int +rte_gpu_mem_unpin(int16_t dev_id, void *ptr) +{ + struct rte_gpu *dev; + + dev = gpu_get_by_id(dev_id); + if (dev == NULL) { + GPU_LOG(ERR, "unpin mem for invalid device ID %d", dev_id); + rte_errno = ENODEV; + return -rte_errno; + } + + if (dev->ops.mem_unpin == NULL) { + rte_errno = ENOTSUP; + return -rte_errno; + } + + if (ptr == NULL) /* dry-run */ + return 0; + + return GPU_DRV_RET(dev->ops.mem_unpin(dev, ptr)); +} + int rte_gpu_wmb(int16_t dev_id) { diff --git a/lib/gpudev/gpudev_driver.h b/lib/gpudev/gpudev_driver.h index cb7b101f2f..13dd8dac43 100644 --- a/lib/gpudev/gpudev_driver.h +++ b/lib/gpudev/gpudev_driver.h @@ -31,6 +31,8 @@ typedef int (rte_gpu_mem_alloc_t)(struct rte_gpu *dev, size_t size, void **ptr); typedef int (rte_gpu_mem_free_t)(struct rte_gpu *dev, void *ptr); typedef int (rte_gpu_mem_register_t)(struct rte_gpu *dev, size_t size, void *ptr); typedef int (rte_gpu_mem_unregister_t)(struct rte_gpu *dev, void *ptr); +typedef int (rte_gpu_mem_pin_t)(struct rte_gpu *dev, size_t size, void *ptr); +typedef int (rte_gpu_mem_unpin_t)(struct rte_gpu *dev, void *ptr); typedef int (rte_gpu_wmb_t)(struct rte_gpu *dev); struct rte_gpu_ops { @@ -46,6 +48,10 @@ struct rte_gpu_ops { rte_gpu_mem_register_t *mem_register; /* Unregister CPU memory from device. */ rte_gpu_mem_unregister_t *mem_unregister; + /* Pin GPU memory. */ + rte_gpu_mem_pin_t *mem_pin; + /* Unpin GPU memory. */ + rte_gpu_mem_unpin_t *mem_unpin; /* Enforce GPU write memory barrier. */ rte_gpu_wmb_t *wmb; }; diff --git a/lib/gpudev/rte_gpudev.h b/lib/gpudev/rte_gpudev.h index fa3f3aad4f..0a9033c6e0 100644 --- a/lib/gpudev/rte_gpudev.h +++ b/lib/gpudev/rte_gpudev.h @@ -447,6 +447,56 @@ int rte_gpu_mem_register(int16_t dev_id, size_t size, void *ptr); __rte_experimental int rte_gpu_mem_unregister(int16_t dev_id, void *ptr); +/** + * @warning + * @b EXPERIMENTAL: this API may change without prior notice. + * + * Pin a chunk of GPU memory to make it accessible from the CPU + * using the memory pointer returned by the function. + * GPU memory has to be allocated via rte_gpu_mem_alloc(). + * + * @param dev_id + * Device ID requiring pinned memory. + * @param size + * Number of bytes to pin. + * Requesting 0 will do nothing. + * @param ptr + * Pointer to the GPU memory area to be pinned. + * NULL is a no-op accepted value. + + * @return + * A pointer to the pinned GPU memory usable by the CPU, otherwise NULL and rte_errno is set: + * - ENODEV if invalid dev_id + * - EINVAL if reserved flags + * - ENOTSUP if operation not supported by the driver + * - E2BIG if size is higher than limit + * - ENOMEM if out of space + * - EPERM if driver error + */ +__rte_experimental +int rte_gpu_mem_pin(int16_t dev_id, size_t size, void *ptr); + +/** + * @warning + * @b EXPERIMENTAL: this API may change without prior notice. + * + * Unpin a chunk of GPU memory previously pinned with rte_gpu_mem_pin() + * + * @param dev_id + * Reference device ID. + * @param ptr + * Pointer to the memory area to be unpinned. + * NULL is a no-op accepted value. + * + * @return + * 0 on success, -rte_errno otherwise: + * - ENODEV if invalid dev_id + * - ENOTSUP if operation not supported by the driver + * - EPERM if driver error + */ +__rte_experimental +int rte_gpu_mem_unpin(int16_t dev_id, void *ptr); + /** * @warning * @b EXPERIMENTAL: this API may change without prior notice. diff --git a/lib/gpudev/version.map b/lib/gpudev/version.map index 2e414c65cc..8fb0f4623b 100644 --- a/lib/gpudev/version.map +++ b/lib/gpudev/version.map @@ -21,7 +21,9 @@ EXPERIMENTAL { rte_gpu_is_valid; rte_gpu_mem_alloc; rte_gpu_mem_free; + rte_gpu_mem_pin; rte_gpu_mem_register; + rte_gpu_mem_unpin; rte_gpu_mem_unregister; rte_gpu_wmb; }; -- 2.17.1