From mboxrd@z Thu Jan 1 00:00:00 1970 From: troy.kisky@boundarydevices.com (Troy Kisky) Date: Fri, 4 Mar 2016 10:28:29 -0700 Subject: [PATCH net-next V2 06/16] net: fec: don't clear all rx queue bits when just one is being checked In-Reply-To: <20160304163854.GD19428@n2100.arm.linux.org.uk> References: <1456360619-24390-1-git-send-email-troy.kisky@boundarydevices.com> <1456360619-24390-7-git-send-email-troy.kisky@boundarydevices.com> <56D9B54B.8020309@boundarydevices.com> <20160304163854.GD19428@n2100.arm.linux.org.uk> Message-ID: <56D9C5BD.5060802@boundarydevices.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 3/4/2016 9:38 AM, Russell King - ARM Linux wrote: > On Fri, Mar 04, 2016 at 09:18:19AM -0700, Troy Kisky wrote: >> On 3/4/2016 2:11 AM, Fugang Duan wrote: >>> From: Troy Kisky Sent: Thursday, February 25, 2016 8:37 AM >>>> To: netdev at vger.kernel.org; davem at davemloft.net; b38611 at freescale.com >>>> Cc: fabio.estevam at freescale.com; l.stach at pengutronix.de; andrew at lunn.ch; >>>> tremyfr at gmail.com; linux at arm.linux.org.uk; linux-arm- >>>> kernel at lists.infradead.org; laci at boundarydevices.com; shawnguo at kernel.org; >>>> johannes at sipsolutions.net; stillcompiling at gmail.com; >>>> sergei.shtylyov at cogentembedded.com; arnd at arndb.de; Troy Kisky >>>> >>>> Subject: [PATCH net-next V2 06/16] net: fec: don't clear all rx queue bits when >>>> just one is being checked >>>> >>>> FEC_ENET_RXF is 3 separate bits, we only check one queue at a time. So, when >>>> the last queue is being checked, it is bad to remove the interrupt on the 1st >>>> queue. >>>> >>>> Also, since this is now done in the napi routine and not the interrupt, it is not >>>> needed. >>>> >>>> Signed-off-by: Troy Kisky >>>> --- >>>> drivers/net/ethernet/freescale/fec_main.c | 2 -- >>>> 1 file changed, 2 deletions(-) >>>> >>>> diff --git a/drivers/net/ethernet/freescale/fec_main.c >>>> b/drivers/net/ethernet/freescale/fec_main.c >>>> index 610cf6c..791f385 100644 >>>> --- a/drivers/net/ethernet/freescale/fec_main.c >>>> +++ b/drivers/net/ethernet/freescale/fec_main.c >>>> @@ -1338,8 +1338,6 @@ static int fec_rxq(struct net_device *ndev, struct >>>> fec_enet_private *fep, >>>> break; >>>> pkt_received++; >>>> >>>> - writel(FEC_ENET_RXF, fep->hwp + FEC_IEVENT); >>>> - >>> >>> We should clear the related rx queue ievent, not remove the code. >>> Pls see commit: db3421c114cf that was submitted by Russell King. >>> >>> No ack the patch. >> >> >> This is now done in patch #4 "net: fec: reduce interrupts" and you could argue >> that it should be squashed into that patch. But I like separating changes >> as much as possible. >> >> >> Russell, this patch and patch #4 will likely need your ack before it will be applied. >> Can you take a look please? > > I stopped caring about the FEC ethernet driver about 18 months ago, > after I ended up dropping a significant pile of fixes on the floor > through the huge number of conflicts and the shere effort of > constantly trying to move them forward. > > My patch series tend to be large because I put concentrated effort > into something for a month, which then gives a problem if conflicts > come up later and the series has to be effectively rewritten from > scratch. It was after the second or third time of facing an almost > total rewrite that happened that I just gave up. > > I've toyed with the idea of forking the driver, but I wouldn't have > time to maintain such a thing. So, right now I just put up with all > the bad quirks, and reset/power cycle the boards when things go wrong. > Right now, I just disable runtime PM support on the FEC to get > stability here. :) > > Sorry, but I can't be of more help. > I can sympathize, I've been almost ready to post my patches numerous times when a huge patch set would hit, and conflict everywhere. Including once about 18 months ago :) That's why I got trigger happy, and first posted my too large set before net-next was opened. It didn't help though, there was already a conflict in net. Troy