From 18e537cd58e8d6932719bfa79cb96a1fbc639199 Mon Sep 17 00:00:00 2001 From: Ursula Braun Date: Thu, 21 Sep 2017 09:16:33 +0200 Subject: [PATCH] net/smc: introduce a delay The number of outstanding work requests is limited. If all work requests are in use, tx processing is postponed to another scheduling of the tx worker. Switch to a delayed worker to have a gap for tx completion queue events before the next retry. Signed-off-by: Ursula Braun Signed-off-by: David S. Miller --- net/smc/smc.h | 2 +- net/smc/smc_close.c | 12 +++++++----- net/smc/smc_tx.c | 12 ++++++++---- 3 files changed, 16 insertions(+), 10 deletions(-) diff --git a/net/smc/smc.h b/net/smc/smc.h index 6e44313e4467..0ccd6fa387ad 100644 --- a/net/smc/smc.h +++ b/net/smc/smc.h @@ -149,7 +149,7 @@ struct smc_connection { atomic_t sndbuf_space; /* remaining space in sndbuf */ u16 tx_cdc_seq; /* sequence # for CDC send */ spinlock_t send_lock; /* protect wr_sends */ - struct work_struct tx_work; /* retry of smc_cdc_msg_send */ + struct delayed_work tx_work; /* retry of smc_cdc_msg_send */ struct smc_host_cdc_msg local_rx_ctrl; /* filled during event_handl. * .prod cf. TCP rcv_nxt diff --git a/net/smc/smc_close.c b/net/smc/smc_close.c index 3c2e166b5d22..5201bc103bd8 100644 --- a/net/smc/smc_close.c +++ b/net/smc/smc_close.c @@ -208,7 +208,7 @@ again: case SMC_ACTIVE: smc_close_stream_wait(smc, timeout); release_sock(sk); - cancel_work_sync(&conn->tx_work); + cancel_delayed_work_sync(&conn->tx_work); lock_sock(sk); if (sk->sk_state == SMC_ACTIVE) { /* send close request */ @@ -234,7 +234,7 @@ again: if (!smc_cdc_rxed_any_close(conn)) smc_close_stream_wait(smc, timeout); release_sock(sk); - cancel_work_sync(&conn->tx_work); + cancel_delayed_work_sync(&conn->tx_work); lock_sock(sk); if (sk->sk_err != ECONNABORTED) { /* confirm close from peer */ @@ -263,7 +263,9 @@ again: /* peer sending PeerConnectionClosed will cause transition */ break; case SMC_PROCESSABORT: - cancel_work_sync(&conn->tx_work); + release_sock(sk); + cancel_delayed_work_sync(&conn->tx_work); + lock_sock(sk); smc_close_abort(conn); sk->sk_state = SMC_CLOSED; smc_close_wait_tx_pends(smc); @@ -425,7 +427,7 @@ again: case SMC_ACTIVE: smc_close_stream_wait(smc, timeout); release_sock(sk); - cancel_work_sync(&conn->tx_work); + cancel_delayed_work_sync(&conn->tx_work); lock_sock(sk); /* send close wr request */ rc = smc_close_wr(conn); @@ -439,7 +441,7 @@ again: if (!smc_cdc_rxed_any_close(conn)) smc_close_stream_wait(smc, timeout); release_sock(sk); - cancel_work_sync(&conn->tx_work); + cancel_delayed_work_sync(&conn->tx_work); lock_sock(sk); /* confirm close from peer */ rc = smc_close_wr(conn); diff --git a/net/smc/smc_tx.c b/net/smc/smc_tx.c index 3c656beb8820..3866573288dd 100644 --- a/net/smc/smc_tx.c +++ b/net/smc/smc_tx.c @@ -24,6 +24,8 @@ #include "smc_cdc.h" #include "smc_tx.h" +#define SMC_TX_WORK_DELAY HZ + /***************************** sndbuf producer *******************************/ /* callback implementation for sk.sk_write_space() @@ -406,7 +408,8 @@ int smc_tx_sndbuf_nonempty(struct smc_connection *conn) goto out_unlock; } rc = 0; - schedule_work(&conn->tx_work); + schedule_delayed_work(&conn->tx_work, + SMC_TX_WORK_DELAY); } goto out_unlock; } @@ -430,7 +433,7 @@ out_unlock: */ static void smc_tx_work(struct work_struct *work) { - struct smc_connection *conn = container_of(work, + struct smc_connection *conn = container_of(to_delayed_work(work), struct smc_connection, tx_work); struct smc_sock *smc = container_of(conn, struct smc_sock, conn); @@ -468,7 +471,8 @@ void smc_tx_consumer_update(struct smc_connection *conn) if (!rc) rc = smc_cdc_msg_send(conn, wr_buf, pend); if (rc < 0) { - schedule_work(&conn->tx_work); + schedule_delayed_work(&conn->tx_work, + SMC_TX_WORK_DELAY); return; } smc_curs_write(&conn->rx_curs_confirmed, @@ -487,6 +491,6 @@ void smc_tx_consumer_update(struct smc_connection *conn) void smc_tx_init(struct smc_sock *smc) { smc->sk.sk_write_space = smc_tx_write_space; - INIT_WORK(&smc->conn.tx_work, smc_tx_work); + INIT_DELAYED_WORK(&smc->conn.tx_work, smc_tx_work); spin_lock_init(&smc->conn.send_lock); }