From 09e0dbbeed82e35ce2cd21e086a6fac934163e2a Mon Sep 17 00:00:00 2001 From: Danil Kipnis Date: Fri, 24 Jul 2020 16:45:06 +0530 Subject: RDMA/rtrs-clt: add an additional random 8 seconds before reconnecting In order to avoid all the clients to start reconnecting at the same time schedule the reconnect dwork with a random jitter of +[0,8] seconds. Fixes: 6a98d71daea1 ("RDMA/rtrs: client: main functionality") Link: https://lore.kernel.org/r/20200724111508.15734-2-haris.iqbal@cloud.ionos.com Signed-off-by: Danil Kipnis Signed-off-by: Md Haris Iqbal Signed-off-by: Jason Gunthorpe --- drivers/infiniband/ulp/rtrs/rtrs-clt.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) (limited to 'drivers/infiniband') diff --git a/drivers/infiniband/ulp/rtrs/rtrs-clt.c b/drivers/infiniband/ulp/rtrs/rtrs-clt.c index 564388a85603..5b31d3b03737 100644 --- a/drivers/infiniband/ulp/rtrs/rtrs-clt.c +++ b/drivers/infiniband/ulp/rtrs/rtrs-clt.c @@ -12,6 +12,7 @@ #include #include +#include #include "rtrs-clt.h" #include "rtrs-log.h" @@ -23,6 +24,12 @@ * leads to "false positives" failed reconnect attempts */ #define RTRS_RECONNECT_BACKOFF 1000 +/* + * Wait for additional random time between 0 and 8 seconds + * before starting to reconnect to avoid clients reconnecting + * all at once in case of a major network outage + */ +#define RTRS_RECONNECT_SEED 8 MODULE_DESCRIPTION("RDMA Transport Client"); MODULE_LICENSE("GPL"); @@ -306,7 +313,8 @@ static void rtrs_rdma_error_recovery(struct rtrs_clt_con *con) */ delay_ms = clt->reconnect_delay_sec * 1000; queue_delayed_work(rtrs_wq, &sess->reconnect_dwork, - msecs_to_jiffies(delay_ms)); + msecs_to_jiffies(delay_ms + + prandom_u32() % RTRS_RECONNECT_SEED)); } else { /* * Error can happen just on establishing new connection, @@ -2503,7 +2511,9 @@ reconnect_again: sess->stats->reconnects.fail_cnt++; delay_ms = clt->reconnect_delay_sec * 1000; queue_delayed_work(rtrs_wq, &sess->reconnect_dwork, - msecs_to_jiffies(delay_ms)); + msecs_to_jiffies(delay_ms + + prandom_u32() % + RTRS_RECONNECT_SEED)); } } -- cgit v1.2.3-58-ga151