From b917147601ea4b890f8331c42a13df3cda8d187d Mon Sep 17 00:00:00 2001 From: Anatoly Burakov Date: Tue, 12 Jun 2018 10:46:14 +0100 Subject: [PATCH] mem: provide thread-unsafe contig walk variant Sometimes, user code needs to walk memseg list while being inside a memory-related callback. Rather than making everyone copy around the same iteration code and depending on DPDK internals, provide an official way to do memseg_contig_walk() inside callbacks. Signed-off-by: Anatoly Burakov --- lib/librte_eal/common/eal_common_memory.c | 28 ++++++++++++---------- lib/librte_eal/common/include/rte_memory.h | 18 ++++++++++++++ lib/librte_eal/rte_eal_version.map | 1 + 3 files changed, 35 insertions(+), 12 deletions(-) diff --git a/lib/librte_eal/common/eal_common_memory.c b/lib/librte_eal/common/eal_common_memory.c index 30671ef823..b69c829e42 100644 --- a/lib/librte_eal/common/eal_common_memory.c +++ b/lib/librte_eal/common/eal_common_memory.c @@ -418,14 +418,11 @@ rte_mem_lock_page(const void *virt) } int __rte_experimental -rte_memseg_contig_walk(rte_memseg_contig_walk_t func, void *arg) +rte_memseg_contig_walk_thread_unsafe(rte_memseg_contig_walk_t func, void *arg) { struct rte_mem_config *mcfg = rte_eal_get_configuration()->mem_config; int i, ms_idx, ret = 0; - /* do not allow allocations/frees/init while we iterate */ - rte_rwlock_read_lock(&mcfg->memory_hotplug_lock); - for (i = 0; i < RTE_MAX_MEMSEG_LISTS; i++) { struct rte_memseg_list *msl = &mcfg->memsegs[i]; const struct rte_memseg *ms; @@ -450,19 +447,26 @@ rte_memseg_contig_walk(rte_memseg_contig_walk_t func, void *arg) len = n_segs * msl->page_sz; ret = func(msl, ms, len, arg); - if (ret < 0) { - ret = -1; - goto out; - } else if (ret > 0) { - ret = 1; - goto out; - } + if (ret) + return ret; ms_idx = rte_fbarray_find_next_used(arr, ms_idx + n_segs); } } -out: + return 0; +} + +int __rte_experimental +rte_memseg_contig_walk(rte_memseg_contig_walk_t func, void *arg) +{ + struct rte_mem_config *mcfg = rte_eal_get_configuration()->mem_config; + int ret = 0; + + /* do not allow allocations/frees/init while we iterate */ + rte_rwlock_read_lock(&mcfg->memory_hotplug_lock); + ret = rte_memseg_contig_walk_thread_unsafe(func, arg); rte_rwlock_read_unlock(&mcfg->memory_hotplug_lock); + return ret; } diff --git a/lib/librte_eal/common/include/rte_memory.h b/lib/librte_eal/common/include/rte_memory.h index aab9f6fe59..aeba38bfa8 100644 --- a/lib/librte_eal/common/include/rte_memory.h +++ b/lib/librte_eal/common/include/rte_memory.h @@ -263,6 +263,24 @@ rte_memseg_contig_walk(rte_memseg_contig_walk_t func, void *arg); int __rte_experimental rte_memseg_list_walk(rte_memseg_list_walk_t func, void *arg); +/** + * Walk each VA-contiguous area without performing any locking. + * + * @note This function does not perform any locking, and is only safe to call + * from within memory-related callback functions. + * + * @param func + * Iterator function + * @param arg + * Argument passed to iterator + * @return + * 0 if walked over the entire list + * 1 if stopped by the user + * -1 if user function reported error + */ +int __rte_experimental +rte_memseg_contig_walk_thread_unsafe(rte_memseg_contig_walk_t func, void *arg); + /** * 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 0557682d78..f01661fb2f 100644 --- a/lib/librte_eal/rte_eal_version.map +++ b/lib/librte_eal/rte_eal_version.map @@ -292,6 +292,7 @@ EXPERIMENTAL { rte_mem_virt2memseg; rte_mem_virt2memseg_list; rte_memseg_contig_walk; + rte_memseg_contig_walk_thread_unsafe; rte_memseg_list_walk; rte_memseg_walk; rte_mp_action_register; -- 2.20.1