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. > 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
