The ENQ portion of the RESERVE macro goes ahead as usual. The reserve bit in the UCB is only set if the ENQ is successful.
The RESERVE macro implies IO to the device. If there is no IO before the subsequent DEQ, the hardware reserve doesn't need to be issued. === > Date: Mon, 25 Jun 2012 16:33:17 +0300 > From: [email protected] > Subject: Re: Why is GRS ENQ needed in SMFDUMP program? > To: [email protected] > > On Mon, 25 Jun 2012 09:25:02 -0400 J R <[email protected]> wrote: > > :>The RESERVE macro did (still does?) not directly do the hardware reserve. > :>Rather, it set a bit in the UCB to tell the next IO to the unit to prepend > :>a reserve CCW to the channel program. > > How would that work with a conditional reserve? How can the O/S know if the > reserve can be satisfied unless the reserve I/O is complete? > > -- > Binyamin Dissen <[email protected]> > http://www.dissensoftware.com > > Director, Dissen Software, Bar & Grill - Israel > > > Should you use the mailblocks package and expect a response from me, > you should preauthorize the dissensoftware.com domain. > > I very rarely bother responding to challenge/response systems, > especially those from irresponsible companies. > ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
