From patchwork Tue Jun 12 09:46:16 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Burakov, Anatoly" X-Patchwork-Id: 41005 X-Patchwork-Delegate: thomas@monjalon.net Return-Path: X-Original-To: patchwork@dpdk.org Delivered-To: patchwork@dpdk.org Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id 04F311E4F0; Tue, 12 Jun 2018 11:46:23 +0200 (CEST) Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by dpdk.org (Postfix) with ESMTP id D89DE1E496 for ; Tue, 12 Jun 2018 11:46:20 +0200 (CEST) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga001.jf.intel.com ([10.7.209.18]) by fmsmga102.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 12 Jun 2018 02:46:18 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.51,214,1526367600"; d="scan'208";a="63861001" Received: from irvmail001.ir.intel.com ([163.33.26.43]) by orsmga001.jf.intel.com with ESMTP; 12 Jun 2018 02:46:17 -0700 Received: from sivswdev01.ir.intel.com (sivswdev01.ir.intel.com [10.237.217.45]) by irvmail001.ir.intel.com (8.14.3/8.13.6/MailSET/Hub) with ESMTP id w5C9kGeM015123 for ; Tue, 12 Jun 2018 10:46:16 +0100 Received: from sivswdev01.ir.intel.com (localhost [127.0.0.1]) by sivswdev01.ir.intel.com with ESMTP id w5C9kGdU021134 for ; Tue, 12 Jun 2018 10:46:16 +0100 Received: (from aburakov@localhost) by sivswdev01.ir.intel.com with LOCAL id w5C9kGlH021130 for dev@dpdk.org; Tue, 12 Jun 2018 10:46:16 +0100 From: Anatoly Burakov To: dev@dpdk.org Date: Tue, 12 Jun 2018 10:46:16 +0100 Message-Id: <3d7db240745dd4ebb6dc254530dc476588f5981b.1528796062.git.anatoly.burakov@intel.com> X-Mailer: git-send-email 1.7.0.7 In-Reply-To: References: In-Reply-To: References: Subject: [dpdk-dev] [PATCH 3/3] mem: provide thread-unsafe memseg list walk variant X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" 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_list_walk() inside callbacks. Also, remove existing reimplementation from memalloc code and use the new API instead. Signed-off-by: Anatoly Burakov --- lib/librte_eal/common/eal_common_memory.c | 29 +++++++++-------- lib/librte_eal/common/include/rte_memory.h | 18 +++++++++++ lib/librte_eal/linuxapp/eal/eal_memalloc.c | 37 +++++----------------- lib/librte_eal/rte_eal_version.map | 1 + 4 files changed, 43 insertions(+), 42 deletions(-) diff --git a/lib/librte_eal/common/eal_common_memory.c b/lib/librte_eal/common/eal_common_memory.c index afe0d5b57..6c4a8d40b 100644 --- a/lib/librte_eal/common/eal_common_memory.c +++ b/lib/librte_eal/common/eal_common_memory.c @@ -883,14 +883,11 @@ rte_memseg_walk(rte_memseg_walk_t func, void *arg) } int __rte_experimental -rte_memseg_list_walk(rte_memseg_list_walk_t func, void *arg) +rte_memseg_list_walk_thread_unsafe(rte_memseg_list_walk_t func, void *arg) { struct rte_mem_config *mcfg = rte_eal_get_configuration()->mem_config; int i, 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]; @@ -898,17 +895,23 @@ rte_memseg_list_walk(rte_memseg_list_walk_t func, void *arg) continue; ret = func(msl, arg); - if (ret < 0) { - ret = -1; - goto out; - } - if (ret > 0) { - ret = 1; - goto out; - } + if (ret) + return ret; } -out: + return 0; +} + +int __rte_experimental +rte_memseg_list_walk(rte_memseg_list_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_list_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 c5a84c333..c4b7f4cff 100644 --- a/lib/librte_eal/common/include/rte_memory.h +++ b/lib/librte_eal/common/include/rte_memory.h @@ -299,6 +299,24 @@ rte_memseg_walk_thread_unsafe(rte_memseg_walk_t func, void *arg); int __rte_experimental rte_memseg_contig_walk_thread_unsafe(rte_memseg_contig_walk_t func, void *arg); +/** + * Walk each allocated memseg list 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_list_walk_thread_unsafe(rte_memseg_list_walk_t func, void *arg); + /** * Dump the physical memory layout to a file. * diff --git a/lib/librte_eal/linuxapp/eal/eal_memalloc.c b/lib/librte_eal/linuxapp/eal/eal_memalloc.c index 8c11f98c9..1ebc4b571 100644 --- a/lib/librte_eal/linuxapp/eal/eal_memalloc.c +++ b/lib/librte_eal/linuxapp/eal/eal_memalloc.c @@ -171,32 +171,6 @@ get_file_size(int fd) return st.st_size; } -/* we cannot use rte_memseg_list_walk() here because we will be holding a - * write lock whenever we enter every function in this file, however copying - * the same iteration code everywhere is not ideal as well. so, use a lockless - * copy of memseg list walk here. - */ -static int -memseg_list_walk_thread_unsafe(rte_memseg_list_walk_t func, void *arg) -{ - struct rte_mem_config *mcfg = rte_eal_get_configuration()->mem_config; - int i, ret = 0; - - for (i = 0; i < RTE_MAX_MEMSEG_LISTS; i++) { - struct rte_memseg_list *msl = &mcfg->memsegs[i]; - - if (msl->base_va == NULL) - continue; - - ret = func(msl, arg); - if (ret < 0) - return -1; - if (ret > 0) - return 1; - } - return 0; -} - /* returns 1 on successful lock, 0 on unsuccessful lock, -1 on error */ static int lock(int fd, int type) { @@ -878,7 +852,8 @@ eal_memalloc_alloc_seg_bulk(struct rte_memseg **ms, int n_segs, size_t page_sz, wa.socket = socket; wa.segs_allocated = 0; - ret = memseg_list_walk_thread_unsafe(alloc_seg_walk, &wa); + /* memalloc is locked, so it's safe to use thread-unsafe version */ + ret = rte_memseg_list_walk_thread_unsafe(alloc_seg_walk, &wa); if (ret == 0) { RTE_LOG(ERR, EAL, "%s(): couldn't find suitable memseg_list\n", __func__); @@ -943,7 +918,10 @@ eal_memalloc_free_seg_bulk(struct rte_memseg **ms, int n_segs) wa.ms = cur; wa.hi = hi; - walk_res = memseg_list_walk_thread_unsafe(free_seg_walk, &wa); + /* memalloc is locked, so it's safe to use thread-unsafe version + */ + walk_res = rte_memseg_list_walk_thread_unsafe(free_seg_walk, + &wa); if (walk_res == 1) continue; if (walk_res == 0) @@ -1230,7 +1208,8 @@ eal_memalloc_sync_with_primary(void) if (rte_eal_process_type() == RTE_PROC_PRIMARY) return 0; - if (memseg_list_walk_thread_unsafe(sync_walk, NULL)) + /* memalloc is locked, so it's safe to call thread-unsafe version */ + if (rte_memseg_list_walk_thread_unsafe(sync_walk, NULL)) return -1; return 0; } diff --git a/lib/librte_eal/rte_eal_version.map b/lib/librte_eal/rte_eal_version.map index 72d32fc39..592ffb867 100644 --- a/lib/librte_eal/rte_eal_version.map +++ b/lib/librte_eal/rte_eal_version.map @@ -288,6 +288,7 @@ EXPERIMENTAL { rte_memseg_contig_walk; rte_memseg_contig_walk_thread_unsafe; rte_memseg_list_walk; + rte_memseg_list_walk_thread_unsafe; rte_memseg_walk; rte_memseg_walk_thread_unsafe; rte_mp_action_register;