On Sun, May 4, 2008 at 5:30 PM, Bart Van Assche <bart.vanassche@xxxxxxxxx> wrote: > On Fri, May 2, 2008 at 5:55 PM, Christoph Hellwig <hch@xxxxxxxxxxxxx> wrote: >> On Fri, May 02, 2008 at 05:53:22PM +0200, Bart Van Assche wrote: >>> Regarding scsi_execute_async(): I didn't know that this API is on its >>> way out. What will it be replaced by, and when ? >> >> blk_execute_rq/blk_execute_rq_nowait plus the block level helpers built >> ontop to build requests. > > Source reading learned me that the function scsi_execute_async() calls > blk_execute_rq_nowait() with 1 as fourth argument, which means that > the request is inserted at the head of the queue. This means that > requests queued with scsi_execute_async() are executed before other > queued requests, and that this function has LIFO (last in first out) > semantics. > > All non-SCSI calls to blk_execute_rq() / blk_execute_rq_nowait() add > requests at the end of the queue (except those calls for terminating > I/O). > > What is the background of this special behavior of the SCSI subsystem ? Is the linux-scsi mailing list the appropriate mailing list to post questions like the above ? Bart. -- 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
