From 4bebdd7a4d2960b2ff6c40b27156d041ea270765 Mon Sep 17 00:00:00 2001 From: Santosh Shilimkar Date: Thu, 10 Sep 2015 11:57:14 -0700 Subject: [PATCH] RDS: defer the over_batch work to send worker Current process gives up if its send work over the batch limit. The work queue will get kicked to finish off any other requests. This fixes remainder condition from commit 443be0e5affe ("RDS: make sure not to loop forever inside rds_send_xmit"). The restart condition is only for the case where we reached to over_batch code for some other reason so just retrying again before giving up. While at it, make sure we use already available 'send_batch_count' parameter instead of magic value. The batch count threshold value of 1024 came via commit 443be0e5affe ("RDS: make sure not to loop forever inside rds_send_xmit"). The idea is to process as big a batch as we can but at the same time we don't hold other waiting processes for send. Hence back-off after the send_batch_count limit (1024) to avoid soft-lock ups. Signed-off-by: Santosh Shilimkar Signed-off-by: Santosh Shilimkar --- net/rds/send.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/net/rds/send.c b/net/rds/send.c index 4df61a515b83..b0acd45a9d42 100644 --- a/net/rds/send.c +++ b/net/rds/send.c @@ -38,6 +38,7 @@ #include #include #include +#include #include "rds.h" @@ -51,7 +52,7 @@ * it to 0 will restore the old behavior (where we looped until we had * drained the queue). */ -static int send_batch_count = 64; +static int send_batch_count = SZ_1K; module_param(send_batch_count, int, 0444); MODULE_PARM_DESC(send_batch_count, " batch factor when working the send queue"); @@ -223,7 +224,7 @@ restart: * through a lot of messages, lets back off and see * if anyone else jumps in */ - if (batch_count >= 1024) + if (batch_count >= send_batch_count) goto over_batch; spin_lock_irqsave(&conn->c_lock, flags); @@ -423,7 +424,9 @@ over_batch: !list_empty(&conn->c_send_queue)) && send_gen == conn->c_send_gen) { rds_stats_inc(s_send_lock_queue_raced); - goto restart; + if (batch_count < send_batch_count) + goto restart; + queue_delayed_work(rds_wq, &conn->c_send_w, 1); } } out: -- 2.20.1