From mboxrd@z Thu Jan 1 00:00:00 1970 From: Heiko Schocher Subject: Re: ata, pcmcia: problem with irq and ata_dev_read_id() Date: Mon, 05 Jul 2010 11:25:45 +0200 Message-ID: <4C31A519.7030806@denx.de> References: <4C034FAE.9090605@denx.de> <4C044C8F.8050406@gmail.com> <4C2833B2.3040209@denx.de> <4C2DFF43.6050502@gmail.com> <4C319741.3060602@denx.de> <4C319D31.60705@gmail.com> Reply-To: hs@denx.de Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7BIT Return-path: Received: from a.relay.invitel.net ([62.77.203.3]:42644 "EHLO a.relay.invitel.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750831Ab0GEJZu (ORCPT ); Mon, 5 Jul 2010 05:25:50 -0400 In-reply-to: <4C319D31.60705@gmail.com> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Tejun Heo Cc: Robert Hancock , Jeff Garzik , linux-ide@vger.kernel.org Hello Tejun, Tejun Heo wrote: > On 07/05/2010 10:26 AM, Heiko Schocher wrote: >> IRQ 26: too many spurious IRQs, disabling and polling for 10k 10msec intervals. >> IRQ 26: system performance may be affected >> handlers: >> [] (ata_sff_interrupt+0x0/0x204) > > Yeah, that's the new polling code kicking in. If the IRQ problem > doesn't persiste (which should be the case here), polling will step > down after a while and everything will return to normal. If you keep > the system running more than ten minutes and use the CF device, does > the kernel complain anymore? No, I can use the CF while kernel is in polling mode, also if the kernel switched back to irq mode: Log, direct after kernel is up: [...] Freeing unused kernel memory: 132k init -bash-3.2# mount -t vfat /dev/sdb1 /home/hs/mnt -bash-3.2# cat /proc/uptime 62.08 14.08 -bash-3.2# cat /proc/interrupts CPU0 17: 0 CPM PIC Level error 18: 0 MPC8XX SIU Level tbint 19: 308 CPM PIC Level cpm_uart 21: 4 CPM PIC Level mpc8xxx_spi 22: 0 MPC8XX SIU Edge ads7846 23: 20043 MPC8XX SIU Level fs_enet-mac 24: 0 MPC8XX SIU Level m8xx-pcmcia 25: 9 MPC8XX SIU Level pata_pcmcia 26: 10000 MPC8XX SIU Level pata_pcmcia 27: 129 CPM PIC Level cpm_i2c LOC: 6408 Local timer interrupts SPU: 0 Spurious interrupts CNT: 0 Performance monitoring interrupts MCE: 0 Machine check exceptions -bash-3.2# No irq is used. -bash-3.2# dmesg [...] Freeing unused kernel memory: 132k init IRQ 26: spurious polling finished, reenabling IRQ -bash-3.2# Now it is back in irq mode: -bash-3.2# cat /proc/uptime 419.65 370.56 -bash-3.2# -bash-3.2# mount -t vfat /dev/sdb1 /home/hs/mnt -bash-3.2# cat /proc/interrupts CPU0 17: 0 CPM PIC Level error 18: 0 MPC8XX SIU Level tbint 19: 956 CPM PIC Level cpm_uart 21: 4 CPM PIC Level mpc8xxx_spi 22: 0 MPC8XX SIU Edge ads7846 23: 20414 MPC8XX SIU Level fs_enet-mac 24: 0 MPC8XX SIU Level m8xx-pcmcia 25: 9 MPC8XX SIU Level pata_pcmcia 26: 10033 MPC8XX SIU Level pata_pcmcia 27: 129 CPM PIC Level cpm_i2c LOC: 10880 Local timer interrupts SPU: 0 Spurious interrupts CNT: 0 Performance monitoring interrupts MCE: 0 Machine check exceptions -bash-3.2# Now it uses the irq ... bye, Heiko -- DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany