From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from dpdk.org (dpdk.org [92.243.14.124]) by inbox.dpdk.org (Postfix) with ESMTP id 0B9C1A2EFC for ; Mon, 16 Sep 2019 12:01:23 +0200 (CEST) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id B1ACE1BED8; Mon, 16 Sep 2019 12:01:22 +0200 (CEST) Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by dpdk.org (Postfix) with ESMTP id 82D371BED5 for ; Mon, 16 Sep 2019 12:01:20 +0200 (CEST) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga101.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 16 Sep 2019 03:01:19 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.64,512,1559545200"; d="scan'208";a="201568865" Received: from unknown (HELO broadwell-dev-4.localdomain) ([10.224.122.193]) by fmsmga001.fm.intel.com with ESMTP; 16 Sep 2019 03:01:17 -0700 From: Nikhil Rao To: harry.van.haaren@intel.com Cc: dev@dpdk.org, Nikhil Rao Date: Mon, 16 Sep 2019 15:31:02 +0530 Message-Id: <1568628062-31332-1-git-send-email-nikhil.rao@intel.com> X-Mailer: git-send-email 1.8.3.1 Subject: [dpdk-dev] [PATCH] service: improve service run performance 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" For a valid service, the core mask of the service is checked against the current core and the corresponding entry in the active_on_lcore array is set or reset. Upto 8 cores share the same cache line for their service active_on_lcore array entries since each entry is a uint8_t. Some number of these entries also share the cache line with the internal_flags member of struct rte_service_spec_impl, hence this false sharing also makes the service_valid() check expensive. Eliminate false sharing by moving the active_on_lcore array to a per-core data structure. The array is now indexed by service id. Signed-off-by: Nikhil Rao --- lib/librte_eal/common/rte_service.c | 16 +++++++--------- 1 file changed, 7 insertions(+), 9 deletions(-) diff --git a/lib/librte_eal/common/rte_service.c b/lib/librte_eal/common/rte_service.c index c3653eb..5d52a81 100644 --- a/lib/librte_eal/common/rte_service.c +++ b/lib/librte_eal/common/rte_service.c @@ -51,7 +51,6 @@ struct rte_service_spec_impl { rte_atomic32_t num_mapped_cores; uint64_t calls; uint64_t cycles_spent; - uint8_t active_on_lcore[RTE_MAX_LCORE]; } __rte_cache_aligned; /* the internal values of a service core */ @@ -60,7 +59,7 @@ struct core_state { uint64_t service_mask; uint8_t runstate; /* running or stopped */ uint8_t is_service_core; /* set if core is currently a service core */ - + uint8_t service_active_on_lcore[RTE_SERVICE_NUM_MAX]; uint64_t loops; uint64_t calls_per_service[RTE_SERVICE_NUM_MAX]; } __rte_cache_aligned; @@ -347,7 +346,7 @@ int32_t rte_service_init(void) static inline int32_t -service_run(uint32_t i, int lcore, struct core_state *cs, uint64_t service_mask) +service_run(uint32_t i, struct core_state *cs, uint64_t service_mask) { if (!service_valid(i)) return -EINVAL; @@ -355,11 +354,11 @@ int32_t rte_service_init(void) if (s->comp_runstate != RUNSTATE_RUNNING || s->app_runstate != RUNSTATE_RUNNING || !(service_mask & (UINT64_C(1) << i))) { - s->active_on_lcore[lcore] = 0; + cs->service_active_on_lcore[i] = 0; return -ENOEXEC; } - s->active_on_lcore[lcore] = 1; + cs->service_active_on_lcore[i] = 1; /* check do we need cmpset, if MT safe or <= 1 core * mapped, atomic ops are not required. @@ -382,7 +381,6 @@ int32_t rte_service_init(void) rte_service_may_be_active(uint32_t id) { uint32_t ids[RTE_MAX_LCORE] = {0}; - struct rte_service_spec_impl *s = &rte_services[id]; int32_t lcore_count = rte_service_lcore_list(ids, RTE_MAX_LCORE); int i; @@ -390,7 +388,7 @@ int32_t rte_service_init(void) return -EINVAL; for (i = 0; i < lcore_count; i++) { - if (s->active_on_lcore[ids[i]]) + if (lcore_states[i].service_active_on_lcore[id]) return 1; } @@ -421,7 +419,7 @@ int32_t rte_service_run_iter_on_app_lcore(uint32_t id, return -EBUSY; } - int ret = service_run(id, rte_lcore_id(), cs, UINT64_MAX); + int ret = service_run(id, cs, UINT64_MAX); if (serialize_mt_unsafe) rte_atomic32_dec(&s->num_mapped_cores); @@ -442,7 +440,7 @@ int32_t rte_service_run_iter_on_app_lcore(uint32_t id, for (i = 0; i < RTE_SERVICE_NUM_MAX; i++) { /* return value ignored as no change to code flow */ - service_run(i, lcore, cs, service_mask); + service_run(i, cs, service_mask); } cs->loops++; -- 1.8.3.1