From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sinan Kaya Subject: Re: [PATCH V2 3/3] scsi: mptxsas: offload IRQ execution Date: Tue, 10 Nov 2015 00:59:54 -0500 Message-ID: <564187DA.6090508@codeaurora.org> References: <1447034266-28003-1-git-send-email-okaya@codeaurora.org> <1447034266-28003-4-git-send-email-okaya@codeaurora.org> <5640481C.9000505@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <5640481C.9000505@suse.de> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: Hannes Reinecke , linux-scsi@vger.kernel.org, timur@codeaurora.org, cov@codeaurora.org, jcm@redhat.com Cc: Abhijit Mahajan , Nagalakshmi Nandigama , linux-arm-msm@vger.kernel.org, "James E.J. Bottomley" , linux-kernel@vger.kernel.org, Sreekanth Reddy , Praveen Krishnamoorthy , agross@codeaurora.org, MPT-FusionLinux.pdl@avagotech.com, linux-arm-kernel@lists.infradead.org List-Id: linux-arm-msm@vger.kernel.org On 11/9/2015 2:15 AM, Hannes Reinecke wrote: > On 11/09/2015 02:57 AM, Sinan Kaya wrote: >> The mpt2sas and mpt3sas drivers are spinning forever in >> their IRQ handlers if there are a lot of jobs queued up >> by the PCIe card. This handler is causing spikes for >> the rest of the system and sluggish behavior. >> >> Marking all MSI interrupts as non-shared and moving the >> MSI interrupts to thread context. This relexes the rest >> of the system execution. >> > NACK. > > If there is a scalability issue when handling interrupts > it should be fixed in the driver directly. > > Looking at the driver is should be possible to implement > a worker thread handling the reply descriptor, and having the > interrupt only to fetch the reply descriptor. > Can you go into the detail about which part of the _base_interrupt function needs to be executed in ISR context and which part can be queued up to worker thread? I'm not familiar with the hardware or the code. That's why, I moved the entire ISR into the thread context. > Cheers, > > Hannes > -- Sinan Kaya Qualcomm Technologies, Inc. on behalf of Qualcomm Innovation Center, Inc. Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project