Re: port-vax/55415: vax no longer preempts in a timely fashion

[Anders Magnusson <ragge%tethuvudet.se@localhost>]

The following reply was made to PR port-vax/55415; it has been noted by GNATS.

From: Anders Magnusson <ragge%tethuvudet.se@localhost>
To: oster%netbsd.org@localhost, gnats-bugs%netbsd.org@localhost
Cc: 
Subject: Re: port-vax/55415: vax no longer preempts in a timely fashion
Date: Thu, 30 Jul 2020 21:24:47 +0200

 > I'm using this:
 >
 > #define    cpu_need_resched(ci, l, flags)        \
 > Â Â Â Â do {Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â  \
 > Â Â Â Â Â Â Â  __USE(flags);Â Â Â Â Â Â Â Â Â Â Â  \
 > Â Â Â Â Â Â Â  mtpr(AST_OK,PR_ASTLVL);Â Â Â Â Â Â Â  \
 > Â Â Â Â Â Â Â  if (mfpr(PR_ASTLVL) != AST_OK)Â  \
 > Â Â Â Â Â Â Â  printf("AST NOT SET!\n"); \
 > Â Â Â Â } while (/*CONSTCOND*/ 0)
 >
 > and the "AST NOT SET!" is never printed.  I can try with splhigh/splx, 
 > and will also look to see if there's a svpctx happening somewhere....
 >
 Ok, I misread you, sorry.  Ignore this.
 Hm, should add a check in some of the context switch routines to see if 
 it is called by something else than an AST (actually, to see if it is 
 called with AST_OK).  If it is, then AST save code should be added.
 
 But, I assume that someone should know whether context switches these 
 days can be called from something else than ASTs?
 
 -- Ragge