From 15d39883ee7dfc023d8a24f5d4b58100e1d04ad9 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Mon, 11 Sep 2023 10:40:22 -0400 Subject: [PATCH] SUNRPC: change the back-channel queue to lwq This removes the need to store and update back-links in the list. It also remove the need for the _bh version of spin_lock(). Signed-off-by: NeilBrown Cc: Trond Myklebust Cc: Anna Schumaker Signed-off-by: Chuck Lever --- include/linux/sunrpc/svc.h | 3 +-- include/linux/sunrpc/xprt.h | 3 ++- net/sunrpc/backchannel_rqst.c | 5 +---- net/sunrpc/svc.c | 3 +-- net/sunrpc/svc_xprt.c | 12 +++--------- net/sunrpc/xprtrdma/backchannel.c | 4 +--- 6 files changed, 9 insertions(+), 21 deletions(-) diff --git a/include/linux/sunrpc/svc.h b/include/linux/sunrpc/svc.h index 8ce1392c1a35..c1feaf0d1542 100644 --- a/include/linux/sunrpc/svc.h +++ b/include/linux/sunrpc/svc.h @@ -90,10 +90,9 @@ struct svc_serv { int (*sv_threadfn)(void *data); #if defined(CONFIG_SUNRPC_BACKCHANNEL) - struct list_head sv_cb_list; /* queue for callback requests + struct lwq sv_cb_list; /* queue for callback requests * that arrive over the same * connection */ - spinlock_t sv_cb_lock; /* protects the svc_cb_list */ bool sv_bc_enabled; /* service uses backchannel */ #endif /* CONFIG_SUNRPC_BACKCHANNEL */ }; diff --git a/include/linux/sunrpc/xprt.h b/include/linux/sunrpc/xprt.h index 4ecc89301eb7..f85d3a0daca2 100644 --- a/include/linux/sunrpc/xprt.h +++ b/include/linux/sunrpc/xprt.h @@ -57,6 +57,7 @@ struct xprt_class; struct seq_file; struct svc_serv; struct net; +#include /* * This describes a complete RPC request @@ -121,7 +122,7 @@ struct rpc_rqst { int rq_ntrans; #if defined(CONFIG_SUNRPC_BACKCHANNEL) - struct list_head rq_bc_list; /* Callback service list */ + struct lwq_node rq_bc_list; /* Callback service list */ unsigned long rq_bc_pa_state; /* Backchannel prealloc state */ struct list_head rq_bc_pa_list; /* Backchannel prealloc list */ #endif /* CONFIG_SUNRPC_BACKCHANEL */ diff --git a/net/sunrpc/backchannel_rqst.c b/net/sunrpc/backchannel_rqst.c index 44b7c89a635f..caa94cf57123 100644 --- a/net/sunrpc/backchannel_rqst.c +++ b/net/sunrpc/backchannel_rqst.c @@ -83,7 +83,6 @@ static struct rpc_rqst *xprt_alloc_bc_req(struct rpc_xprt *xprt) return NULL; req->rq_xprt = xprt; - INIT_LIST_HEAD(&req->rq_bc_list); /* Preallocate one XDR receive buffer */ if (xprt_alloc_xdr_buf(&req->rq_rcv_buf, gfp_flags) < 0) { @@ -367,8 +366,6 @@ void xprt_complete_bc_request(struct rpc_rqst *req, uint32_t copied) dprintk("RPC: add callback request to list\n"); xprt_get(xprt); - spin_lock(&bc_serv->sv_cb_lock); - list_add(&req->rq_bc_list, &bc_serv->sv_cb_list); - spin_unlock(&bc_serv->sv_cb_lock); + lwq_enqueue(&req->rq_bc_list, &bc_serv->sv_cb_list); svc_pool_wake_idle_thread(&bc_serv->sv_pools[0]); } diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c index efe7a58ccbdc..7d4c10e609dc 100644 --- a/net/sunrpc/svc.c +++ b/net/sunrpc/svc.c @@ -438,8 +438,7 @@ EXPORT_SYMBOL_GPL(svc_bind); static void __svc_init_bc(struct svc_serv *serv) { - INIT_LIST_HEAD(&serv->sv_cb_list); - spin_lock_init(&serv->sv_cb_lock); + lwq_init(&serv->sv_cb_list); } #else static void diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c index 28ca7db55da1..fee83d1024bc 100644 --- a/net/sunrpc/svc_xprt.c +++ b/net/sunrpc/svc_xprt.c @@ -705,7 +705,7 @@ svc_thread_should_sleep(struct svc_rqst *rqstp) #if defined(CONFIG_SUNRPC_BACKCHANNEL) if (svc_is_backchannel(rqstp)) { - if (!list_empty(&rqstp->rq_server->sv_cb_list)) + if (!lwq_empty(&rqstp->rq_server->sv_cb_list)) return false; } #endif @@ -878,18 +878,12 @@ void svc_recv(struct svc_rqst *rqstp) struct svc_serv *serv = rqstp->rq_server; struct rpc_rqst *req; - spin_lock_bh(&serv->sv_cb_lock); - req = list_first_entry_or_null(&serv->sv_cb_list, - struct rpc_rqst, rq_bc_list); + req = lwq_dequeue(&serv->sv_cb_list, + struct rpc_rqst, rq_bc_list); if (req) { - list_del(&req->rq_bc_list); - spin_unlock_bh(&serv->sv_cb_lock); svc_thread_wake_next(rqstp); - svc_process_bc(req, rqstp); - return; } - spin_unlock_bh(&serv->sv_cb_lock); } #endif } diff --git a/net/sunrpc/xprtrdma/backchannel.c b/net/sunrpc/xprtrdma/backchannel.c index bfc434ec52a7..8c817e755262 100644 --- a/net/sunrpc/xprtrdma/backchannel.c +++ b/net/sunrpc/xprtrdma/backchannel.c @@ -263,9 +263,7 @@ void rpcrdma_bc_receive_call(struct rpcrdma_xprt *r_xprt, /* Queue rqst for ULP's callback service */ bc_serv = xprt->bc_serv; xprt_get(xprt); - spin_lock(&bc_serv->sv_cb_lock); - list_add(&rqst->rq_bc_list, &bc_serv->sv_cb_list); - spin_unlock(&bc_serv->sv_cb_lock); + lwq_enqueue(&rqst->rq_bc_list, &bc_serv->sv_cb_list); svc_pool_wake_idle_thread(&bc_serv->sv_pools[0]);