On Sat, Sep 18, 2010 at 12:57:58PM -0700, Nicholas A. Bellinger wrote: > On Fri, 2010-09-17 at 21:45 -0500, Mike Christie wrote: > > On 09/17/2010 02:03 PM, Joe Eykholt wrote: > > > > > > How about instead of adding use_serial_number, let's just have the > > > drivers that want a serial number call scsi_cmd_get_serial() > > > > I think this sounds better. > > > > In that case I will go ahead and add explict scsi_cmd_get_serial() calls > to the LLDs that use struct scsi_cmnd->serial_number in anything beyond > an obvious and simple informational purpose. > > > You could also convert drivers to the host tagging if you needed a > > unique id for each command sent to a host. > > Hmmm, what does this entail again..? > > > > > > and stop calling it from scsi_dispatch_cmd()? AFAICT, it's only > > > used in debug messages in some drivers. I didn't find other usages > > > but didn't do an exhaustive search. > > > > The comments for serial_number say that it is only supposed to be used > > for debugging printks and most drivers use it for that. > > So I would suppose it would be OK for those drivers to continue to > printk serial_number to show the internal serial_number allocation is > now disabled by default. > > > However, it looks like mpt and dpt_i2o are using it for error handling > > and/or lookup type of operations. I think the mpt* uses are not needed > > in the abort checks. > > > > In that case, then adding an explict scsi_cmd_get_serial() call in mpt* > and dpt_i20 ->queuecommand() callers would be a good first step. > > > And eata is using it for ordering and tracking or something. It could > > probably be converted to the host tagging if or what you suggested if it > > needs the uniqueue id. > > Adding an explict scsi_cmd_get_serial() for eata for now, and we can > consider LLD canidates for host tag conversion as a future step. > > > > > zfcp looks like it copies it. It does not look like the driver needs it. > > > > Ok, I will look at removing it's usage in zfcp or if necessary add an > the explict scsi_cmd_get_serial() call. In zfcp, the serial_number is only accessed for writing it to debug traces. With the change that the driver has to request the serial number through use_serial_number, simply remove the serial number from zfcp. Thanks, Christof > > > scsi_error.c uses it in scsi_try_to_abort_cmd to check if a command has > > completed, but I think that can be done by checking if REQ_ATOM_COMPLETE > > is set. > > Hmmm, good catch here. Jejb and hch, does this item work for you..? > > If so then I will take another peek for any ML uses of a struct > scsi_cmnd->serial_number that need to be addressed, and include Joe's > and Mike's recommendations into a v3 series. > > Thanks for your comments here Mike! > > --nab -- 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
