> -----Original Message----- > From: Christoph Hellwig [mailto:hch@xxxxxxxxxxxxx] > Sent: Monday, 25 August, 2014 9:51 AM > To: Elliott, Robert (Server Storage) > Cc: linux-scsi@xxxxxxxxxxxxxxx > Subject: Re: scsi-mq and 3.17rc1 > > On Mon, Aug 25, 2014 at 02:31:58PM +0000, Elliott, Robert (Server > Storage) wrote: > > Two scsi-mq tips: > > > > 1. Several people have been wondering how to enable scsi-mq. > > Add this to your kernel command line (e.g., in /boot/grub/grub.conf > > if using grub-1): > > scsi_mod.use_blk_mq=Y > > Btw, I heard a few complaints about this, and one suggestion would be > to add a config option to enable it by default. Would you or others > like this? Yes. It shouldn't become a command line parameter that clutters up user boot configuration files for years. A config option will ease the transition from defaulting to off to defaulting to on. The command line parameter could override both ways: config default=N, scsi_mod.use_blk_mq=Y: on config default=N, scsi_mod.use_blk_mq=N: off config default=N, scsi_mod.use_blk_mq not specified: off config default=Y, scsi_mod.use_blk_mq=Y: on config default=Y, scsi_mod.use_blk_mq=N: off config default=Y, scsi_mod.use_blk_mq not specified: on Right now, shost->hostt->disable_blk_mq also allows the LLD to override to off if needed. Perhaps that should move to shost->disable_blk_mq so the LLD could have per-scsi_host control (e.g., let the user specify they want it off for for an HBA attached mostly to HDDs and on for an HBA attached mostly to SSDs). I also suggest that scsi_add_host_with_dma use shost_printk to indicate what was selected for each scsi_host. --- Rob Elliott HP Server Storage -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
