diff options
Diffstat (limited to 'rpc/rpc-lib/src/rpc-drc.c')
| -rw-r--r-- | rpc/rpc-lib/src/rpc-drc.c | 855 |
1 files changed, 855 insertions, 0 deletions
diff --git a/rpc/rpc-lib/src/rpc-drc.c b/rpc/rpc-lib/src/rpc-drc.c new file mode 100644 index 00000000000..de8dc630626 --- /dev/null +++ b/rpc/rpc-lib/src/rpc-drc.c @@ -0,0 +1,855 @@ +/* + Copyright (c) 2013 Red Hat, Inc. <http://www.redhat.com> + This file is part of GlusterFS. + + This file is licensed to you under your choice of the GNU Lesser + General Public License, version 3 or any later version (LGPLv3 or + later), or the GNU General Public License, version 2 (GPLv2), in all + cases as published by the Free Software Foundation. +*/ + +#include "rpcsvc.h" +#ifndef RPC_DRC_H +#include "rpc-drc.h" +#endif +#include <glusterfs/locking.h> +#include <glusterfs/statedump.h> +#include <glusterfs/mem-pool.h> + +#include <netinet/in.h> +#include <unistd.h> + +/** + * rpcsvc_drc_op_destroy - Destroys the cached reply + * + * @param drc - the main drc structure + * @param reply - the cached reply to destroy + * @return NULL if reply is destroyed, reply otherwise + */ +static drc_cached_op_t * +rpcsvc_drc_op_destroy(rpcsvc_drc_globals_t *drc, drc_cached_op_t *reply) +{ + GF_ASSERT(drc); + GF_ASSERT(reply); + + if (reply->state == DRC_OP_IN_TRANSIT) + return reply; + + iobref_unref(reply->msg.iobref); + if (reply->msg.rpchdr) + GF_FREE(reply->msg.rpchdr); + if (reply->msg.proghdr) + GF_FREE(reply->msg.proghdr); + if (reply->msg.progpayload) + GF_FREE(reply->msg.progpayload); + + list_del(&reply->global_list); + reply->client->op_count--; + drc->op_count--; + mem_put(reply); + reply = NULL; + + return reply; +} + +/** + * rpcsvc_drc_op_rb_unref - This function is used in rb tree cleanup only + * + * @param reply - the cached reply to unref + * @param drc - the main drc structure + * @return void + */ +static void +rpcsvc_drc_rb_op_destroy(void *reply, void *drc) +{ + rpcsvc_drc_op_destroy(drc, (drc_cached_op_t *)reply); +} + +/** + * rpcsvc_remove_drc_client - Cleanup the drc client + * + * @param client - the drc client to be removed + * @return void + */ +static void +rpcsvc_remove_drc_client(drc_client_t *client) +{ + rb_destroy(client->rbtree, rpcsvc_drc_rb_op_destroy); + list_del(&client->client_list); + GF_FREE(client); +} + +/** + * rpcsvc_client_lookup - Given a sockaddr_storage, find the client if it exists + * + * @param drc - the main drc structure + * @param sockaddr - the network address of the client to be looked up + * @return drc client if it exists, NULL otherwise + */ +static drc_client_t * +rpcsvc_client_lookup(rpcsvc_drc_globals_t *drc, + struct sockaddr_storage *sockaddr) +{ + drc_client_t *client = NULL; + + GF_ASSERT(drc); + GF_ASSERT(sockaddr); + + if (list_empty(&drc->clients_head)) + return NULL; + + list_for_each_entry(client, &drc->clients_head, client_list) + { + if (gf_sock_union_equal_addr(&client->sock_union, + (union gf_sock_union *)sockaddr)) + return client; + } + + return NULL; +} + +/** + * drc_compare_reqs - Used by rbtree to determine if incoming req matches with + * an existing node(cached reply) in rbtree + * + * @param item - pointer to the incoming req + * @param rb_node_data - pointer to an rbtree node (cached reply) + * @param param - drc pointer - unused here, but used in *op_destroy + * @return 0 if req matches reply, else (req->xid - reply->xid) + */ +int +drc_compare_reqs(const void *item, const void *rb_node_data, void *param) +{ + int ret = -1; + drc_cached_op_t *req = NULL; + drc_cached_op_t *reply = NULL; + + GF_ASSERT(item); + GF_ASSERT(rb_node_data); + GF_ASSERT(param); + + req = (drc_cached_op_t *)item; + reply = (drc_cached_op_t *)rb_node_data; + + ret = req->xid - reply->xid; + if (ret != 0) + return ret; + + if (req->prognum == reply->prognum && req->procnum == reply->procnum && + req->progversion == reply->progversion) + return 0; + + return 1; +} + +/** + * drc_init_client_cache - initialize a drc client and its rb tree + * + * @param drc - the main drc structure + * @param client - the drc client to be initialized + * @return 0 on success, -1 on failure + */ +static int +drc_init_client_cache(rpcsvc_drc_globals_t *drc, drc_client_t *client) +{ + GF_ASSERT(drc); + GF_ASSERT(client); + + client->rbtree = rb_create(drc_compare_reqs, drc, NULL); + if (!client->rbtree) { + gf_log(GF_RPCSVC, GF_LOG_DEBUG, "rb tree creation failed"); + return -1; + } + + return 0; +} + +/** + * rpcsvc_get_drc_client - find the drc client with given sockaddr, else + * allocate and initialize a new drc client + * + * @param drc - the main drc structure + * @param sockaddr - network address of client + * @return drc client on success, NULL on failure + */ +static drc_client_t * +rpcsvc_get_drc_client(rpcsvc_drc_globals_t *drc, + struct sockaddr_storage *sockaddr) +{ + drc_client_t *client = NULL; + + GF_ASSERT(drc); + GF_ASSERT(sockaddr); + + client = rpcsvc_client_lookup(drc, sockaddr); + if (client) + goto out; + + /* if lookup fails, allocate cache for the new client */ + client = GF_CALLOC(1, sizeof(drc_client_t), gf_common_mt_drc_client_t); + if (!client) + goto out; + + GF_ATOMIC_INIT(client->ref, 0); + client->sock_union = (union gf_sock_union) * sockaddr; + client->op_count = 0; + INIT_LIST_HEAD(&client->client_list); + + if (drc_init_client_cache(drc, client)) { + gf_log(GF_RPCSVC, GF_LOG_DEBUG, "initialization of drc client failed"); + GF_FREE(client); + client = NULL; + goto out; + } + drc->client_count++; + + list_add(&client->client_list, &drc->clients_head); + +out: + return client; +} + +/** + * rpcsvc_need_drc - Determine if a request needs DRC service + * + * @param req - incoming request + * @return 1 if DRC is needed for req, 0 otherwise + */ +int +rpcsvc_need_drc(rpcsvc_request_t *req) +{ + rpcsvc_actor_t *actor = NULL; + rpcsvc_drc_globals_t *drc = NULL; + + GF_ASSERT(req); + GF_ASSERT(req->svc); + + drc = req->svc->drc; + + if (!drc || drc->status == DRC_UNINITIATED) + return 0; + + actor = rpcsvc_program_actor(req); + if (!actor) + return 0; + + return (actor->op_type == DRC_NON_IDEMPOTENT && drc->type != DRC_TYPE_NONE); +} + +/** + * rpcsvc_drc_client_ref - ref the drc client + * + * @param client - the drc client to ref + * @return client + */ +static drc_client_t * +rpcsvc_drc_client_ref(drc_client_t *client) +{ + GF_ASSERT(client); + GF_ATOMIC_INC(client->ref); + return client; +} + +/** + * rpcsvc_drc_client_unref - unref the drc client, and destroy + * the client on last unref + * + * @param drc - the main drc structure + * @param client - the drc client to unref + * @return NULL if it is the last unref, client otherwise + */ +static drc_client_t * +rpcsvc_drc_client_unref(rpcsvc_drc_globals_t *drc, drc_client_t *client) +{ + uint32_t refcount; + + GF_ASSERT(drc); + + refcount = GF_ATOMIC_DEC(client->ref); + if (!refcount) { + drc->client_count--; + rpcsvc_remove_drc_client(client); + client = NULL; + } + + return client; +} + +/** + * rpcsvc_drc_lookup - lookup a request to see if it is already cached + * + * @param req - incoming request + * @return cached reply of req if found, NULL otherwise + */ +drc_cached_op_t * +rpcsvc_drc_lookup(rpcsvc_request_t *req) +{ + drc_client_t *client = NULL; + drc_cached_op_t *reply = NULL; + drc_cached_op_t new = { + .xid = req->xid, + .prognum = req->prognum, + .progversion = req->progver, + .procnum = req->procnum, + }; + + GF_ASSERT(req); + + if (!req->trans->drc_client) { + client = rpcsvc_get_drc_client(req->svc->drc, + &req->trans->peerinfo.sockaddr); + if (!client) + goto out; + + req->trans->drc_client = rpcsvc_drc_client_ref(client); + } + + client = req->trans->drc_client; + + if (client->op_count == 0) + goto out; + + reply = rb_find(client->rbtree, &new); + +out: + return reply; +} + +/** + * rpcsvc_send_cached_reply - send the cached reply for the incoming request + * + * @param req - incoming request (which is a duplicate in this case) + * @param reply - the cached reply for req + * @return 0 on successful reply submission, -1 or other non-zero value + * otherwise + */ +int +rpcsvc_send_cached_reply(rpcsvc_request_t *req, drc_cached_op_t *reply) +{ + int ret = 0; + + GF_ASSERT(req); + GF_ASSERT(reply); + + gf_log(GF_RPCSVC, GF_LOG_DEBUG, + "sending cached reply: xid: %d, " + "client: %s", + req->xid, req->trans->peerinfo.identifier); + + rpcsvc_drc_client_ref(reply->client); + ret = rpcsvc_transport_submit( + req->trans, reply->msg.rpchdr, reply->msg.rpchdrcount, + reply->msg.proghdr, reply->msg.proghdrcount, reply->msg.progpayload, + reply->msg.progpayloadcount, reply->msg.iobref, req->trans_private); + rpcsvc_drc_client_unref(req->svc->drc, reply->client); + + return ret; +} + +/** + * rpcsvc_cache_reply - cache the reply for the processed request 'req' + * + * @param req - processed request + * @param iobref - iobref structure of the reply + * @param rpchdr - rpc header of the reply + * @param rpchdrcount - size of rpchdr + * @param proghdr - program header of the reply + * @param proghdrcount - size of proghdr + * @param payload - payload of the reply if any + * @param payloadcount - size of payload + * @return 0 on success, -1 on failure + */ +int +rpcsvc_cache_reply(rpcsvc_request_t *req, struct iobref *iobref, + struct iovec *rpchdr, int rpchdrcount, struct iovec *proghdr, + int proghdrcount, struct iovec *payload, int payloadcount) +{ + int ret = -1; + drc_cached_op_t *reply = NULL; + + GF_ASSERT(req); + GF_ASSERT(req->reply); + + reply = req->reply; + + reply->state = DRC_OP_CACHED; + + reply->msg.iobref = iobref_ref(iobref); + + reply->msg.rpchdrcount = rpchdrcount; + reply->msg.rpchdr = iov_dup(rpchdr, rpchdrcount); + + reply->msg.proghdrcount = proghdrcount; + reply->msg.proghdr = iov_dup(proghdr, proghdrcount); + + reply->msg.progpayloadcount = payloadcount; + if (payloadcount) + reply->msg.progpayload = iov_dup(payload, payloadcount); + + // rpcsvc_drc_client_unref (req->svc->drc, req->trans->drc_client); + // rpcsvc_drc_op_unref (req->svc->drc, reply); + ret = 0; + + return ret; +} + +/** + * rpcsvc_vacate_drc_entries - free up some percentage of drc cache + * based on the lru factor + * + * @param drc - the main drc structure + * @return void + */ +static void +rpcsvc_vacate_drc_entries(rpcsvc_drc_globals_t *drc) +{ + uint32_t i = 0; + uint32_t n = 0; + drc_cached_op_t *reply = NULL; + drc_cached_op_t *tmp = NULL; + drc_client_t *client = NULL; + + GF_ASSERT(drc); + + n = drc->global_cache_size / drc->lru_factor; + + list_for_each_entry_safe_reverse(reply, tmp, &drc->cache_head, global_list) + { + /* Don't delete ops that are in transit */ + if (reply->state == DRC_OP_IN_TRANSIT) + continue; + + client = reply->client; + + rb_delete(client->rbtree, reply); + + rpcsvc_drc_op_destroy(drc, reply); + rpcsvc_drc_client_unref(drc, client); + i++; + if (i >= n) + break; + } +} + +/** + * rpcsvc_add_op_to_cache - insert the cached op into the client rbtree and drc + * list + * + * @param drc - the main drc structure + * @param reply - the op to be inserted + * @return 0 on success, -1 on failure + */ +static int +rpcsvc_add_op_to_cache(rpcsvc_drc_globals_t *drc, drc_cached_op_t *reply) +{ + drc_client_t *client = NULL; + drc_cached_op_t **tmp_reply = NULL; + + GF_ASSERT(drc); + GF_ASSERT(reply); + + client = reply->client; + + /* cache is full, free up some space */ + if (drc->op_count >= drc->global_cache_size) + rpcsvc_vacate_drc_entries(drc); + + tmp_reply = (drc_cached_op_t **)rb_probe(client->rbtree, reply); + if (!tmp_reply) { + /* mem alloc failed */ + return -1; + } else if (*tmp_reply != reply) { + /* should never happen */ + gf_log(GF_RPCSVC, GF_LOG_ERROR, "DRC failed to detect duplicates"); + return -1; + } + + client->op_count++; + list_add(&reply->global_list, &drc->cache_head); + drc->op_count++; + + return 0; +} + +/** + * rpcsvc_cache_request - cache the in-transition incoming request + * + * @param req - incoming request + * @return 0 on success, -1 on failure + */ +int +rpcsvc_cache_request(rpcsvc_request_t *req) +{ + int ret = -1; + drc_client_t *client = NULL; + drc_cached_op_t *reply = NULL; + rpcsvc_drc_globals_t *drc = NULL; + + GF_ASSERT(req); + + drc = req->svc->drc; + + client = req->trans->drc_client; + if (!client) { + gf_log(GF_RPCSVC, GF_LOG_DEBUG, "drc client is NULL"); + goto out; + } + + reply = mem_get0(drc->mempool); + if (!reply) + goto out; + + reply->client = rpcsvc_drc_client_ref(client); + reply->xid = req->xid; + reply->prognum = req->prognum; + reply->progversion = req->progver; + reply->procnum = req->procnum; + reply->state = DRC_OP_IN_TRANSIT; + req->reply = reply; + INIT_LIST_HEAD(&reply->global_list); + + ret = rpcsvc_add_op_to_cache(drc, reply); + if (ret) { + req->reply = NULL; + rpcsvc_drc_op_destroy(drc, reply); + rpcsvc_drc_client_unref(drc, client); + gf_log(GF_RPCSVC, GF_LOG_DEBUG, "Failed to add op to drc cache"); + } + +out: + return ret; +} + +/** + * + * rpcsvc_drc_priv - function which dumps the drc state + * + * @param drc - the main drc structure + * @return 0 on success, -1 on failure + */ +int32_t +rpcsvc_drc_priv(rpcsvc_drc_globals_t *drc) +{ + int i = 0; + char key[GF_DUMP_MAX_BUF_LEN] = {0}; + drc_client_t *client = NULL; + char ip[INET6_ADDRSTRLEN] = {0}; + + if (!drc || drc->status == DRC_UNINITIATED) { + gf_log(GF_RPCSVC, GF_LOG_DEBUG, + "DRC is " + "uninitialized, not dumping its state"); + return 0; + } + + gf_proc_dump_add_section("rpc.drc"); + + if (TRY_LOCK(&drc->lock)) + return -1; + + gf_proc_dump_build_key(key, "drc", "type"); + gf_proc_dump_write(key, "%d", drc->type); + + gf_proc_dump_build_key(key, "drc", "client_count"); + gf_proc_dump_write(key, "%d", drc->client_count); + + gf_proc_dump_build_key(key, "drc", "current_cache_size"); + gf_proc_dump_write(key, "%d", drc->op_count); + + gf_proc_dump_build_key(key, "drc", "max_cache_size"); + gf_proc_dump_write(key, "%d", drc->global_cache_size); + + gf_proc_dump_build_key(key, "drc", "lru_factor"); + gf_proc_dump_write(key, "%d", drc->lru_factor); + + gf_proc_dump_build_key(key, "drc", "duplicate_request_count"); + gf_proc_dump_write(key, "%" PRIu64, drc->cache_hits); + + gf_proc_dump_build_key(key, "drc", "in_transit_duplicate_requests"); + gf_proc_dump_write(key, "%" PRIu64, drc->intransit_hits); + + list_for_each_entry(client, &drc->clients_head, client_list) + { + gf_proc_dump_build_key(key, "client", "%d.ip-address", i); + memset(ip, 0, INET6_ADDRSTRLEN); + switch (client->sock_union.storage.ss_family) { + case AF_INET: + gf_proc_dump_write( + key, "%s", + inet_ntop(AF_INET, &client->sock_union.sin.sin_addr.s_addr, + ip, INET_ADDRSTRLEN)); + break; + case AF_INET6: + gf_proc_dump_write( + key, "%s", + inet_ntop(AF_INET6, &client->sock_union.sin6.sin6_addr, ip, + INET6_ADDRSTRLEN)); + break; + default: + gf_proc_dump_write(key, "%s", "N/A"); + } + + gf_proc_dump_build_key(key, "client", "%d.ref_count", i); + gf_proc_dump_write(key, "%" PRIu32, GF_ATOMIC_GET(client->ref)); + gf_proc_dump_build_key(key, "client", "%d.op_count", i); + gf_proc_dump_write(key, "%d", client->op_count); + i++; + } + + UNLOCK(&drc->lock); + return 0; +} + +/** + * rpcsvc_drc_notify - function which is notified of RPC transport events + * + * @param svc - pointer to rpcsvc_t structure of the rpc + * @param xl - pointer to the xlator + * @param event - the event which triggered this notify + * @param data - the transport structure + * @return 0 on success, -1 on failure + */ +int +rpcsvc_drc_notify(rpcsvc_t *svc, void *xl, rpcsvc_event_t event, void *data) +{ + int ret = -1; + rpc_transport_t *trans = NULL; + drc_client_t *client = NULL; + rpcsvc_drc_globals_t *drc = NULL; + + GF_ASSERT(svc); + GF_ASSERT(svc->drc); + GF_ASSERT(data); + + drc = svc->drc; + + if (drc->status == DRC_UNINITIATED || drc->type == DRC_TYPE_NONE) + return 0; + + LOCK(&drc->lock); + { + trans = (rpc_transport_t *)data; + client = rpcsvc_get_drc_client(drc, &trans->peerinfo.sockaddr); + if (!client) + goto unlock; + + switch (event) { + case RPCSVC_EVENT_ACCEPT: + trans->drc_client = rpcsvc_drc_client_ref(client); + ret = 0; + break; + + case RPCSVC_EVENT_DISCONNECT: + ret = 0; + if (list_empty(&drc->clients_head)) + break; + /* should be the last unref */ + trans->drc_client = NULL; + rpcsvc_drc_client_unref(drc, client); + break; + + default: + break; + } + } +unlock: + UNLOCK(&drc->lock); + return ret; +} + +/** + * rpcsvc_drc_init - Initialize the duplicate request cache service + * + * @param svc - pointer to rpcsvc_t structure of the rpc + * @param options - the options dictionary which configures drc + * @return 0 on success, non-zero integer on failure + */ +int +rpcsvc_drc_init(rpcsvc_t *svc, dict_t *options) +{ + int ret = 0; + uint32_t drc_type = 0; + uint32_t drc_size = 0; + uint32_t drc_factor = 0; + rpcsvc_drc_globals_t *drc = NULL; + + GF_ASSERT(svc); + GF_ASSERT(options); + + /* Toggle DRC on/off, when more drc types(persistent/cluster) + * are added, we shouldn't treat this as boolean. */ + ret = dict_get_str_boolean(options, "nfs.drc", _gf_false); + if (ret == -1) { + gf_log(GF_RPCSVC, GF_LOG_INFO, "drc user options need second look"); + ret = _gf_false; + } + + gf_log(GF_RPCSVC, GF_LOG_INFO, "DRC is turned %s", (ret ? "ON" : "OFF")); + + /*DRC off, nothing to do */ + if (ret == _gf_false) + return (0); + + drc = GF_CALLOC(1, sizeof(rpcsvc_drc_globals_t), + gf_common_mt_drc_globals_t); + if (!drc) + return (-1); + + LOCK_INIT(&drc->lock); + svc->drc = drc; + + /* Specify type of DRC to be used */ + ret = dict_get_uint32(options, "nfs.drc-type", &drc_type); + if (ret) { + gf_log(GF_RPCSVC, GF_LOG_DEBUG, + "drc type not set. Continuing with default"); + drc_type = DRC_DEFAULT_TYPE; + } + + /* Set the global cache size (no. of ops to cache) */ + ret = dict_get_uint32(options, "nfs.drc-size", &drc_size); + if (ret) { + gf_log(GF_RPCSVC, GF_LOG_DEBUG, + "drc size not set. Continuing with default size"); + drc_size = DRC_DEFAULT_CACHE_SIZE; + } + + LOCK(&drc->lock); + + drc->type = drc_type; + drc->global_cache_size = drc_size; + + /* Mempool for cached ops */ + drc->mempool = mem_pool_new(drc_cached_op_t, drc->global_cache_size); + if (!drc->mempool) { + UNLOCK(&drc->lock); + gf_log(GF_RPCSVC, GF_LOG_ERROR, + "Failed to get mempool for DRC, drc-size: %d", drc_size); + ret = -1; + goto post_unlock; + } + + /* What percent of cache to be evicted whenever it fills up */ + ret = dict_get_uint32(options, "nfs.drc-lru-factor", &drc_factor); + if (ret) { + gf_log(GF_RPCSVC, GF_LOG_DEBUG, + "drc lru factor not set. Continuing with policy default"); + drc_factor = DRC_DEFAULT_LRU_FACTOR; + } + + drc->lru_factor = (drc_lru_factor_t)drc_factor; + + INIT_LIST_HEAD(&drc->clients_head); + INIT_LIST_HEAD(&drc->cache_head); + + ret = rpcsvc_register_notify(svc, rpcsvc_drc_notify, THIS); + if (ret) { + UNLOCK(&drc->lock); + gf_log(GF_RPCSVC, GF_LOG_ERROR, + "registration of drc_notify function failed"); + goto post_unlock; + } + + drc->status = DRC_INITIATED; + UNLOCK(&drc->lock); + gf_log(GF_RPCSVC, GF_LOG_DEBUG, "drc init successful"); +post_unlock: + if (ret == -1) { + if (drc->mempool) { + mem_pool_destroy(drc->mempool); + drc->mempool = NULL; + } + GF_FREE(drc); + svc->drc = NULL; + } + return ret; +} + +int +rpcsvc_drc_deinit(rpcsvc_t *svc) +{ + rpcsvc_drc_globals_t *drc = NULL; + + if (!svc) + return (-1); + + drc = svc->drc; + if (!drc) + return (0); + + LOCK(&drc->lock); + (void)rpcsvc_unregister_notify(svc, rpcsvc_drc_notify, THIS); + if (drc->mempool) { + mem_pool_destroy(drc->mempool); + drc->mempool = NULL; + } + UNLOCK(&drc->lock); + + GF_FREE(drc); + svc->drc = NULL; + + return (0); +} + +int +rpcsvc_drc_reconfigure(rpcsvc_t *svc, dict_t *options) +{ + int ret = -1; + gf_boolean_t enable_drc = _gf_false; + rpcsvc_drc_globals_t *drc = NULL; + uint32_t drc_size = 0; + + /* Input sanitization */ + if ((!svc) || (!options)) + return (-1); + + /* If DRC was not enabled before, Let rpcsvc_drc_init() to + * take care of DRC initialization part. + */ + drc = svc->drc; + if (!drc) { + return rpcsvc_drc_init(svc, options); + } + + /* DRC was already enabled before. Going to be reconfigured. Check + * if reconfigured options contain "nfs.drc" and "nfs.drc-size". + * + * NB: If DRC is "OFF", "drc-size" has no role to play. + * So, "drc-size" gets evaluated IFF DRC is "ON". + * + * If DRC is reconfigured, + * case 1: DRC is "ON" + * sub-case 1: drc-size remains same + * ACTION: Nothing to do. + * sub-case 2: drc-size just changed + * ACTION: rpcsvc_drc_deinit() followed by + * rpcsvc_drc_init(). + * + * case 2: DRC is "OFF" + * ACTION: rpcsvc_drc_deinit() + */ + ret = dict_get_str_boolean(options, "nfs.drc", _gf_false); + if (ret < 0) + ret = _gf_false; + + enable_drc = ret; + gf_log(GF_RPCSVC, GF_LOG_INFO, "DRC is turned %s", (ret ? "ON" : "OFF")); + + /* case 1: DRC is "ON"*/ + if (enable_drc) { + /* Fetch drc-size if reconfigured */ + if (dict_get_uint32(options, "nfs.drc-size", &drc_size)) + drc_size = DRC_DEFAULT_CACHE_SIZE; + + /* case 1: sub-case 1*/ + if (drc->global_cache_size == drc_size) + return (0); + + /* case 1: sub-case 2*/ + (void)rpcsvc_drc_deinit(svc); + return rpcsvc_drc_init(svc, options); + } + + /* case 2: DRC is "OFF" */ + return rpcsvc_drc_deinit(svc); +} |