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 A4777A2F18 for ; Thu, 3 Oct 2019 13:52:24 +0200 (CEST) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id 773941C067; Thu, 3 Oct 2019 13:52:24 +0200 (CEST) Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by dpdk.org (Postfix) with ESMTP id 0DCB71C05C for ; Thu, 3 Oct 2019 13:52:22 +0200 (CEST) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga103.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 03 Oct 2019 04:52:22 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.67,252,1566889200"; d="scan'208";a="198508717" Received: from irsmsx109.ger.corp.intel.com ([163.33.3.23]) by FMSMGA003.fm.intel.com with ESMTP; 03 Oct 2019 04:52:20 -0700 Received: from irsmsx105.ger.corp.intel.com ([169.254.7.164]) by IRSMSX109.ger.corp.intel.com ([169.254.13.29]) with mapi id 14.03.0439.000; Thu, 3 Oct 2019 12:52:19 +0100 From: "Ananyev, Konstantin" To: Honnappa Nagarahalli , "stephen@networkplumber.org" , "paulmck@linux.ibm.com" CC: "Wang, Yipeng1" , "Medvedkin, Vladimir" , "Ruifeng Wang (Arm Technology China)" , Dharmik Thakkar , "dev@dpdk.org" , nd , nd Thread-Topic: [PATCH v3 2/3] lib/rcu: add resource reclamation APIs Thread-Index: AQHVeCGdR5HV3Y+YjUaapXAJb26OSqdHskfQgAC4HQCAAGc/8A== Date: Thu, 3 Oct 2019 11:52:19 +0000 Message-ID: <2601191342CEEE43887BDE71AB9772580191970813@irsmsx105.ger.corp.intel.com> References: <20190906094534.36060-1-ruifeng.wang@arm.com> <20191001062917.35578-1-honnappa.nagarahalli@arm.com> <20191001062917.35578-3-honnappa.nagarahalli@arm.com> <2601191342CEEE43887BDE71AB9772580191970035@irsmsx105.ger.corp.intel.com> In-Reply-To: Accept-Language: en-IE, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-titus-metadata-40: eyJDYXRlZ29yeUxhYmVscyI6IiIsIk1ldGFkYXRhIjp7Im5zIjoiaHR0cDpcL1wvd3d3LnRpdHVzLmNvbVwvbnNcL0ludGVsMyIsImlkIjoiZDc5MmNlMGUtMGVhNi00ZmExLTkzZTYtMWQ0YjE5NWQ5NDYzIiwicHJvcHMiOlt7Im4iOiJDVFBDbGFzc2lmaWNhdGlvbiIsInZhbHMiOlt7InZhbHVlIjoiQ1RQX05UIn1dfV19LCJTdWJqZWN0TGFiZWxzIjpbXSwiVE1DVmVyc2lvbiI6IjE3LjEwLjE4MDQuNDkiLCJUcnVzdGVkTGFiZWxIYXNoIjoiUnVYdDFhZjEwUWhMRHFEeDRMSWIxMTFjS05vUURhR00zUlFhRlIxZmJLNEsyMFlaUlRyYUQ5MlJPN0ZDZDB3MyJ9 x-ctpclassification: CTP_NT dlp-product: dlpe-windows dlp-version: 11.2.0.6 dlp-reaction: no-action x-originating-ip: [163.33.239.180] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Subject: Re: [dpdk-dev] [PATCH v3 2/3] lib/rcu: add resource reclamation APIs 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" > -----Original Message----- > From: Honnappa Nagarahalli [mailto:Honnappa.Nagarahalli@arm.com] > Sent: Thursday, October 3, 2019 7:42 AM > To: Ananyev, Konstantin ; stephen@networkpl= umber.org; paulmck@linux.ibm.com > Cc: Wang, Yipeng1 ; Medvedkin, Vladimir ; Ruifeng Wang (Arm Technology > China) ; Dharmik Thakkar ;= Honnappa Nagarahalli > ; dev@dpdk.org; nd ; nd > Subject: RE: [PATCH v3 2/3] lib/rcu: add resource reclamation APIs >=20 > > > > > + > > > +/* Reclaim resources from the defer queue. */ int > > > +rte_rcu_qsbr_dq_reclaim(struct rte_rcu_qsbr_dq *dq) { > > > + uint32_t max_cnt; > > > + uint32_t cnt; > > > + void *token; > > > + uint64_t *tmp; > > > + uint32_t i; > > > + > > > + if (dq =3D=3D NULL) { > > > + rte_log(RTE_LOG_ERR, rte_rcu_log_type, > > > + "%s(): Invalid input parameter\n", __func__); > > > + rte_errno =3D EINVAL; > > > + > > > + return 1; > > > + } > > > + > > > + /* Anything to reclaim? */ > > > + if (rte_ring_count(dq->r) =3D=3D 0) > > > + return 0; > > > + > > > + /* Reclaim at the max 1/16th the total number of entries. */ > > > + max_cnt =3D dq->size >> RTE_RCU_QSBR_MAX_RECLAIM_LIMIT; > > > + max_cnt =3D (max_cnt =3D=3D 0) ? dq->size : max_cnt; > > > + cnt =3D 0; > > > + > > > + /* Check reader threads quiescent state and reclaim resources */ > > > + while ((cnt < max_cnt) && (rte_ring_peek(dq->r, &token) =3D=3D 0) &= & > > > + (rte_rcu_qsbr_check(dq->v, (uint64_t)((uintptr_t)token), false) > > > > One more thing I forgot to ask - how this construct supposed to work on= 32 > > bit machines? > > peek() will return 32-bit value, while qsbr_check() operates with 64bi= t > > tokens... > > As I understand in that case you need to peek() 2 elems. > Yes, that is the intention. Ring APIs with desired element size will help= address the 32b machines. Or serialized dequeue :) >=20 > > Might work, but still think better to introduce serialize version of > > ring_dequeue() See my other mail about re_ring_peek(). > > > > > > > + =3D=3D 1)) { > > > + (void)rte_ring_sc_dequeue(dq->r, &token); > > > + /* The resource to dequeue needs to be a multiple of 64b > > > + * due to the limitation of the rte_ring implementation. > > > + */ > > > + for (i =3D 0, tmp =3D (uint64_t *)dq->e; i < dq->esize/8; > > > + i++, tmp++) > > > + (void)rte_ring_sc_dequeue(dq->r, > > > + (void *)(uintptr_t)tmp); > > > + dq->f(dq->p, dq->e); > > > + > > > + cnt++; > > > + } > > > + > > > + rte_log(RTE_LOG_INFO, rte_rcu_log_type, > > > + "%s(): Reclaimed %u resources\n", __func__, cnt); > > > + > > > + if (cnt =3D=3D 0) { > > > + /* No resources were reclaimed */ > > > + rte_errno =3D EAGAIN; > > > + return 1; > > > + } > > > + > > > + return 0; > > > +} > > > + > > > +/* Delete a defer queue. */ > > > +int > > > +rte_rcu_qsbr_dq_delete(struct rte_rcu_qsbr_dq *dq) { > > > + if (dq =3D=3D NULL) { > > > + rte_log(RTE_LOG_ERR, rte_rcu_log_type, > > > + "%s(): Invalid input parameter\n", __func__); > > > + rte_errno =3D EINVAL; > > > + > > > + return 1; > > > + } > > > + > > > + /* Reclaim all the resources */ > > > + if (rte_rcu_qsbr_dq_reclaim(dq) !=3D 0) > > > + /* Error number is already set by the reclaim API */ > > > + return 1; > > > + > > > + rte_ring_free(dq->r); > > > + rte_free(dq); > > > + > > > + return 0; > > > +} > > > + > > > int rte_rcu_log_type; > > > > > > RTE_INIT(rte_rcu_register) > > > diff --git a/lib/librte_rcu/rte_rcu_qsbr.h > > > b/lib/librte_rcu/rte_rcu_qsbr.h index c80f15c00..185d4b50a 100644 > > > --- a/lib/librte_rcu/rte_rcu_qsbr.h > > > +++ b/lib/librte_rcu/rte_rcu_qsbr.h > > > @@ -34,6 +34,7 @@ extern "C" { > > > #include > > > #include > > > #include > > > +#include > > > > > > extern int rte_rcu_log_type; > > > > > > @@ -109,6 +110,67 @@ struct rte_rcu_qsbr { > > > */ > > > } __rte_cache_aligned; > > > > > > +/** > > > + * Call back function called to free the resources. > > > + * > > > + * @param p > > > + * Pointer provided while creating the defer queue > > > + * @param e > > > + * Pointer to the resource data stored on the defer queue > > > + * > > > + * @return > > > + * None > > > + */ > > > +typedef void (*rte_rcu_qsbr_free_resource)(void *p, void *e); > > > + > > > +#define RTE_RCU_QSBR_DQ_NAMESIZE RTE_RING_NAMESIZE > > > + > > > +/** > > > + * Trigger automatic reclamation after 1/8th the defer queue is ful= l. > > > + */ > > > +#define RTE_RCU_QSBR_AUTO_RECLAIM_LIMIT 3 > > > + > > > +/** > > > + * Reclaim at the max 1/16th the total number of resources. > > > + */ > > > +#define RTE_RCU_QSBR_MAX_RECLAIM_LIMIT 4 > > > + > > > +/** > > > + * Parameters used when creating the defer queue. > > > + */ > > > +struct rte_rcu_qsbr_dq_parameters { > > > + const char *name; > > > + /**< Name of the queue. */ > > > + uint32_t size; > > > + /**< Number of entries in queue. Typically, this will be > > > + * the same as the maximum number of entries supported in the > > > + * lock free data structure. > > > + * Data structures with unbounded number of entries is not > > > + * supported currently. > > > + */ > > > + uint32_t esize; > > > + /**< Size (in bytes) of each element in the defer queue. > > > + * This has to be multiple of 8B as the rte_ring APIs > > > + * support 8B element sizes only. > > > + */ > > > + rte_rcu_qsbr_free_resource f; > > > + /**< Function to call to free the resource. */ > > > + void *p; > > > + /**< Pointer passed to the free function. Typically, this is the > > > + * pointer to the data structure to which the resource to free > > > + * belongs. This can be NULL. > > > + */ > > > + struct rte_rcu_qsbr *v; > > > + /**< RCU QSBR variable to use for this defer queue */ }; > > > + > > > +/* RTE defer queue structure. > > > + * This structure holds the defer queue. The defer queue is used to > > > + * hold the deleted entries from the data structure that are not > > > + * yet freed. > > > + */ > > > +struct rte_rcu_qsbr_dq; > > > + > > > /** > > > * @warning > > > * @b EXPERIMENTAL: this API may change without prior notice @@ > > > -648,6 +710,113 @@ __rte_experimental int rte_rcu_qsbr_dump(FILE *f= , > > > struct rte_rcu_qsbr *v); > > > > > > +/** > > > + * @warning > > > + * @b EXPERIMENTAL: this API may change without prior notice > > > + * > > > + * Create a queue used to store the data structure elements that can > > > + * be freed later. This queue is referred to as 'defer queue'. > > > + * > > > + * @param params > > > + * Parameters to create a defer queue. > > > + * @return > > > + * On success - Valid pointer to defer queue > > > + * On error - NULL > > > + * Possible rte_errno codes are: > > > + * - EINVAL - NULL parameters are passed > > > + * - ENOMEM - Not enough memory > > > + */ > > > +__rte_experimental > > > +struct rte_rcu_qsbr_dq * > > > +rte_rcu_qsbr_dq_create(const struct rte_rcu_qsbr_dq_parameters > > > +*params); > > > + > > > +/** > > > + * @warning > > > + * @b EXPERIMENTAL: this API may change without prior notice > > > + * > > > + * Enqueue one resource to the defer queue and start the grace perio= d. > > > + * The resource will be freed later after at least one grace period > > > + * is over. > > > + * > > > + * If the defer queue is full, it will attempt to reclaim resources. > > > + * It will also reclaim resources at regular intervals to avoid > > > + * the defer queue from growing too big. > > > + * > > > + * This API is not multi-thread safe. It is expected that the caller > > > + * provides multi-thread safety by locking a mutex or some other mea= ns. > > > + * > > > + * A lock free multi-thread writer algorithm could achieve > > > +multi-thread > > > + * safety by creating and using one defer queue per thread. > > > + * > > > + * @param dq > > > + * Defer queue to allocate an entry from. > > > + * @param e > > > + * Pointer to resource data to copy to the defer queue. The size o= f > > > + * the data to copy is equal to the element size provided when the > > > + * defer queue was created. > > > + * @return > > > + * On success - 0 > > > + * On error - 1 with rte_errno set to > > > + * - EINVAL - NULL parameters are passed > > > + * - ENOSPC - Defer queue is full. This condition can not happen > > > + * if the defer queue size is equal (or larger) than the > > > + * number of elements in the data structure. > > > + */ > > > +__rte_experimental > > > +int > > > +rte_rcu_qsbr_dq_enqueue(struct rte_rcu_qsbr_dq *dq, void *e); > > > + > > > +/** > > > + * @warning > > > + * @b EXPERIMENTAL: this API may change without prior notice > > > + * > > > + * Reclaim resources from the defer queue. > > > + * > > > + * This API is not multi-thread safe. It is expected that the caller > > > + * provides multi-thread safety by locking a mutex or some other mea= ns. > > > + * > > > + * A lock free multi-thread writer algorithm could achieve > > > +multi-thread > > > + * safety by creating and using one defer queue per thread. > > > + * > > > + * @param dq > > > + * Defer queue to reclaim an entry from. > > > + * @return > > > + * On successful reclamation of at least 1 resource - 0 > > > + * On error - 1 with rte_errno set to > > > + * - EINVAL - NULL parameters are passed > > > + * - EAGAIN - None of the resources have completed at least 1 grac= e > > period, > > > + * try again. > > > + */ > > > +__rte_experimental > > > +int > > > +rte_rcu_qsbr_dq_reclaim(struct rte_rcu_qsbr_dq *dq); > > > + > > > +/** > > > + * @warning > > > + * @b EXPERIMENTAL: this API may change without prior notice > > > + * > > > + * Delete a defer queue. > > > + * > > > + * It tries to reclaim all the resources on the defer queue. > > > + * If any of the resources have not completed the grace period > > > + * the reclamation stops and returns immediately. The rest of > > > + * the resources are not reclaimed and the defer queue is not > > > + * freed. > > > + * > > > + * @param dq > > > + * Defer queue to delete. > > > + * @return > > > + * On success - 0 > > > + * On error - 1 > > > + * Possible rte_errno codes are: > > > + * - EINVAL - NULL parameters are passed > > > + * - EAGAIN - Some of the resources have not completed at least 1 = grace > > > + * period, try again. > > > + */ > > > +__rte_experimental > > > +int > > > +rte_rcu_qsbr_dq_delete(struct rte_rcu_qsbr_dq *dq); > > > + > > > #ifdef __cplusplus > > > } > > > #endif > > > diff --git a/lib/librte_rcu/rte_rcu_qsbr_pvt.h > > > b/lib/librte_rcu/rte_rcu_qsbr_pvt.h > > > new file mode 100644 > > > index 000000000..2122bc36a > > > --- /dev/null > > > +++ b/lib/librte_rcu/rte_rcu_qsbr_pvt.h > > > @@ -0,0 +1,46 @@ > > > +/* SPDX-License-Identifier: BSD-3-Clause > > > + * Copyright (c) 2019 Arm Limited > > > + */ > > > + > > > +#ifndef _RTE_RCU_QSBR_PVT_H_ > > > +#define _RTE_RCU_QSBR_PVT_H_ > > > + > > > +/** > > > + * This file is private to the RCU library. It should not be include= d > > > + * by the user of this library. > > > + */ > > > + > > > +#ifdef __cplusplus > > > +extern "C" { > > > +#endif > > > + > > > +#include "rte_rcu_qsbr.h" > > > + > > > +/* RTE defer queue structure. > > > + * This structure holds the defer queue. The defer queue is used to > > > + * hold the deleted entries from the data structure that are not > > > + * yet freed. > > > + */ > > > +struct rte_rcu_qsbr_dq { > > > + struct rte_rcu_qsbr *v; /**< RCU QSBR variable used by this queue.*= / > > > + struct rte_ring *r; /**< RCU QSBR defer queue. */ > > > + uint32_t size; > > > + /**< Number of elements in the defer queue */ > > > + uint32_t esize; > > > + /**< Size (in bytes) of data stored on the defer queue */ > > > + rte_rcu_qsbr_free_resource f; > > > + /**< Function to call to free the resource. */ > > > + void *p; > > > + /**< Pointer passed to the free function. Typically, this is the > > > + * pointer to the data structure to which the resource to free > > > + * belongs. > > > + */ > > > + char e[0]; > > > + /**< Temporary storage to copy the defer queue element. */ }; > > > + > > > +#ifdef __cplusplus > > > +} > > > +#endif > > > + > > > +#endif /* _RTE_RCU_QSBR_PVT_H_ */ > > > diff --git a/lib/librte_rcu/rte_rcu_version.map > > > b/lib/librte_rcu/rte_rcu_version.map > > > index f8b9ef2ab..dfac88a37 100644 > > > --- a/lib/librte_rcu/rte_rcu_version.map > > > +++ b/lib/librte_rcu/rte_rcu_version.map > > > @@ -8,6 +8,10 @@ EXPERIMENTAL { > > > rte_rcu_qsbr_synchronize; > > > rte_rcu_qsbr_thread_register; > > > rte_rcu_qsbr_thread_unregister; > > > + rte_rcu_qsbr_dq_create; > > > + rte_rcu_qsbr_dq_enqueue; > > > + rte_rcu_qsbr_dq_reclaim; > > > + rte_rcu_qsbr_dq_delete; > > > > > > local: *; > > > }; > > > diff --git a/lib/meson.build b/lib/meson.build index > > > e5ff83893..0e1be8407 100644 > > > --- a/lib/meson.build > > > +++ b/lib/meson.build > > > @@ -11,7 +11,9 @@ > > > libraries =3D [ > > > 'kvargs', # eal depends on kvargs > > > 'eal', # everything depends on eal > > > - 'ring', 'mempool', 'mbuf', 'net', 'meter', 'ethdev', 'pci', # core > > > + 'ring', > > > + 'rcu', # rcu depends on ring > > > + 'mempool', 'mbuf', 'net', 'meter', 'ethdev', 'pci', # core > > > 'cmdline', > > > 'metrics', # bitrate/latency stats depends on this > > > 'hash', # efd depends on this > > > @@ -22,7 +24,7 @@ libraries =3D [ > > > 'gro', 'gso', 'ip_frag', 'jobstats', > > > 'kni', 'latencystats', 'lpm', 'member', > > > 'power', 'pdump', 'rawdev', > > > - 'rcu', 'reorder', 'sched', 'security', 'stack', 'vhost', > > > + 'reorder', 'sched', 'security', 'stack', 'vhost', > > > # ipsec lib depends on net, crypto and security > > > 'ipsec', > > > # add pkt framework libs which use other libs from above > > > -- > > > 2.17.1