From bed794188693bfed53ab6d94a441f4d8f102e7c4 Mon Sep 17 00:00:00 2001 From: Anatoly Burakov Date: Thu, 20 Dec 2018 15:32:41 +0000 Subject: [PATCH] mem: allow usage of non-heap external memory in multiprocess Add multiprocess support for externally allocated memory areas that are not added to DPDK heap (and add relevant doc sections). Signed-off-by: Anatoly Burakov Acked-by: Yongseok Koh --- .../prog_guide/env_abstraction_layer.rst | 3 + lib/librte_eal/common/eal_common_memory.c | 42 +++++++++++++ lib/librte_eal/common/include/rte_memory.h | 59 +++++++++++++++++++ lib/librte_eal/rte_eal_version.map | 2 + 4 files changed, 106 insertions(+) diff --git a/doc/guides/prog_guide/env_abstraction_layer.rst b/doc/guides/prog_guide/env_abstraction_layer.rst index 190662e805..5aaac0bd25 100644 --- a/doc/guides/prog_guide/env_abstraction_layer.rst +++ b/doc/guides/prog_guide/env_abstraction_layer.rst @@ -290,11 +290,14 @@ The expected workflow is as follows: * Register memory within DPDK - If IOVA table is not specified, IOVA addresses will be assumed to be unavailable + - Other processes must attach to the memory area before they can use it * Perform DMA mapping with ``rte_vfio_dma_map`` if needed * Use the memory area in your application * If memory area is no longer needed, it can be unregistered - If the area was mapped for DMA, unmapping must be performed before unregistering memory + - Other processes must detach from the memory area before it can be + unregistered Since these externally allocated memory areas will not be managed by DPDK, it is therefore up to the user application to decide how to use them and what to do diff --git a/lib/librte_eal/common/eal_common_memory.c b/lib/librte_eal/common/eal_common_memory.c index ea43c1362e..051159f803 100644 --- a/lib/librte_eal/common/eal_common_memory.c +++ b/lib/librte_eal/common/eal_common_memory.c @@ -852,6 +852,48 @@ unlock: return ret; } +static int +sync_memory(void *va_addr, size_t len, bool attach) +{ + struct rte_mem_config *mcfg = rte_eal_get_configuration()->mem_config; + struct rte_memseg_list *msl; + int ret = 0; + + if (va_addr == NULL || len == 0) { + rte_errno = EINVAL; + return -1; + } + rte_rwlock_write_lock(&mcfg->memory_hotplug_lock); + + /* find our segment */ + msl = malloc_heap_find_external_seg(va_addr, len); + if (msl == NULL) { + rte_errno = ENOENT; + ret = -1; + goto unlock; + } + if (attach) + ret = rte_fbarray_attach(&msl->memseg_arr); + else + ret = rte_fbarray_detach(&msl->memseg_arr); + +unlock: + rte_rwlock_write_unlock(&mcfg->memory_hotplug_lock); + return ret; +} + +int __rte_experimental +rte_extmem_attach(void *va_addr, size_t len) +{ + return sync_memory(va_addr, len, true); +} + +int __rte_experimental +rte_extmem_detach(void *va_addr, size_t len) +{ + return sync_memory(va_addr, len, false); +} + /* init memory subsystem */ int rte_eal_memory_init(void) diff --git a/lib/librte_eal/common/include/rte_memory.h b/lib/librte_eal/common/include/rte_memory.h index ff23fc2c12..7ca703bb19 100644 --- a/lib/librte_eal/common/include/rte_memory.h +++ b/lib/librte_eal/common/include/rte_memory.h @@ -435,6 +435,10 @@ rte_memseg_get_fd_offset_thread_unsafe(const struct rte_memseg *ms, * @note This API will not perform any DMA mapping. It is expected that user * will do that themselves. * + * @note Before accessing this memory in other processes, it needs to be + * attached in each of those processes by calling ``rte_extmem_attach`` in + * each other process. + * * @param va_addr * Start of virtual area to register. Must be aligned by ``page_sz``. * @param len @@ -472,6 +476,9 @@ rte_extmem_register(void *va_addr, size_t len, rte_iova_t iova_addrs[], * @note This API will not perform any DMA unmapping. It is expected that user * will do that themselves. * + * @note Before calling this function, all other processes must call + * ``rte_extmem_detach`` to detach from the memory area. + * * @param va_addr * Start of virtual area to unregister * @param len @@ -486,6 +493,58 @@ rte_extmem_register(void *va_addr, size_t len, rte_iova_t iova_addrs[], int __rte_experimental rte_extmem_unregister(void *va_addr, size_t len); +/** + * @warning + * @b EXPERIMENTAL: this API may change without prior notice + * + * Attach to external memory chunk registered in another process. + * + * @note Using this API is mutually exclusive with ``rte_malloc`` family of + * API's. + * + * @note This API will not perform any DMA mapping. It is expected that user + * will do that themselves. + * + * @param va_addr + * Start of virtual area to register + * @param len + * Length of virtual area to register + * + * @return + * - 0 on success + * - -1 in case of error, with rte_errno set to one of the following: + * EINVAL - one of the parameters was invalid + * ENOENT - memory chunk was not found + */ +int __rte_experimental +rte_extmem_attach(void *va_addr, size_t len); + +/** + * @warning + * @b EXPERIMENTAL: this API may change without prior notice + * + * Detach from external memory chunk registered in another process. + * + * @note Using this API is mutually exclusive with ``rte_malloc`` family of + * API's. + * + * @note This API will not perform any DMA unmapping. It is expected that user + * will do that themselves. + * + * @param va_addr + * Start of virtual area to unregister + * @param len + * Length of virtual area to unregister + * + * @return + * - 0 on success + * - -1 in case of error, with rte_errno set to one of the following: + * EINVAL - one of the parameters was invalid + * ENOENT - memory chunk was not found + */ +int __rte_experimental +rte_extmem_detach(void *va_addr, size_t len); + /** * Dump the physical memory layout to a file. * diff --git a/lib/librte_eal/rte_eal_version.map b/lib/librte_eal/rte_eal_version.map index 593691a14f..eb5f7b9cbd 100644 --- a/lib/librte_eal/rte_eal_version.map +++ b/lib/librte_eal/rte_eal_version.map @@ -296,6 +296,8 @@ EXPERIMENTAL { rte_devargs_remove; rte_devargs_type_count; rte_eal_cleanup; + rte_extmem_attach; + rte_extmem_detach; rte_extmem_register; rte_extmem_unregister; rte_fbarray_attach; -- 2.20.1