From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH net-next 10/31] cxgb4/iw_cxgb4: Doorbell Drop Avoidance Bug Fixes. Date: Thu, 27 Feb 2014 13:05:44 -0500 (EST) Message-ID: <20140227.130544.1892840202381139797.davem@davemloft.net> References: <1393427230-14532-11-git-send-email-hariprasad@chelsio.com> <20140226.181216.1563503549713890339.davem@davemloft.net> <005101cf33df$00749e40$015ddac0$@opengridcomputing.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: hariprasad-ut6Up61K2wZBDgjK7y7TUQ@public.gmane.org, netdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, roland-BHEL68pLQRGGvPXPguhicg@public.gmane.org, kumaras-ut6Up61K2wZBDgjK7y7TUQ@public.gmane.org, dm-ut6Up61K2wZBDgjK7y7TUQ@public.gmane.org, leedom-ut6Up61K2wZBDgjK7y7TUQ@public.gmane.org, santosh-ut6Up61K2wZBDgjK7y7TUQ@public.gmane.org, nirranjan-ut6Up61K2wZBDgjK7y7TUQ@public.gmane.org To: swise-7bPotxP6k4+P2YhJcF5u+vpXobYPEAuW@public.gmane.org Return-path: In-Reply-To: <005101cf33df$00749e40$015ddac0$@opengridcomputing.com> Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: netdev.vger.kernel.org From: "Steve Wise" Date: Thu, 27 Feb 2014 11:11:49 -0600 >> >> > -static int allow_db_fc_on_t5; >> > -module_param(allow_db_fc_on_t5, int, 0644); >> > -MODULE_PARM_DESC(allow_db_fc_on_t5, >> > - "Allow DB Flow Control on T5 (default = 0)"); >> > - >> > -static int allow_db_coalescing_on_t5; >> > -module_param(allow_db_coalescing_on_t5, int, 0644); >> > -MODULE_PARM_DESC(allow_db_coalescing_on_t5, >> > - "Allow DB Coalescing on T5 (default = 0)"); >> >> Module parameters are a user facing interface. >> >> You cannot just delete, or change the semantics of, the ones you feel >> like doing so to. > > I see your point on user facing interfaces. These module params were > added initially to allow tweaking the db drop recovery for T5 devices in > the thought that we might need it. It turns out T5 doesn't suffer from > this issue. These params default to 0 anyway, and I doubt anyone has > changed them. Disabling the hw db coalescing feature proved problematic > and it turned out to even make the issue worse, so I removed it totally > at the recommendation from the HW engineers, and put in place the new > design which better rate controls things under heavy load. You have to keep the old ones around. -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html