statclock: move profil(2), GPROF code to profclock(), gmonclock()

This patch isolates profil(2) and GPROF from statclock().  Currently,
statclock() implements both profil(2) and GPROF through a complex
mechanism involving both platform code (setstatclockrate) and the
scheduler (pscnt, psdiv, and psratio).  We have a machine-independent
interface to the clock interrupt hardware now, so we no longer need to
do it this way.

- Move profil(2)-specific code from statclock() to a new clock
  interrupt callback, profclock(), in subr_prof.c.  Each
  schedstate_percpu has its own profclock handle.  The profclock is
  enabled/disabled for a given CPU when it is needed by the running
  thread during mi_switch() and sched_exit().

- Move GPROF-specific code from statclock() to a new clock interrupt
  callback, gmonclock(), in subr_prof.c.  Where available, each cpu_info
  has its own gmonclock handle .  The gmonclock is enabled/disabled for
  a given CPU via sysctl(2) in prof_state_toggle().

- Both profclock() and gmonclock() have a fixed period, profclock_period,
  that is initialized during initclocks().

- Export clockintr_advance(), clockintr_cancel(), clockintr_establish(),
  and clockintr_stagger() via <sys/clockintr.h>.  They have external
  callers now.

- Delete pscnt, psdiv, psratio.  From schedstate_percpu, also delete
  spc_pscnt and spc_psdiv.  The statclock frequency is not dynamic
  anymore so these variables are now useless.

- Delete code/state related to the dynamic statclock frequency from
  kern_clockintr.c.  The statclock frequency can still be pseudo-random,
  so move the contents of clockintr_statvar_init() into clockintr_init().

With input from miod@, deraadt@, and claudio@.  Early revisions
cleaned up by claudio.  Early revisions tested by claudio@.  Tested by
cheloha@ on amd64, arm64, macppc, octeon, and sparc64 (sun4v).
Compile- and boot- tested on i386 by mlarkin@.  riscv64 compilation
bugs found by mlarkin@.  Tested on riscv64 by jca@.  Tested on
powerpc64 by gkoehler@.

2 files changed, 3 insertions, 3 deletions

diff --git a/sys/arch/sh/include/cpu.h b/sys/arch/sh/include/cpu.h
index 8bd445f1737..a080751e833 100644
--- a/sys/arch/sh/include/cpu.h
+++ b/sys/arch/sh/include/cpu.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: cpu.h,v 1.34 2022/12/06 01:19:35 cheloha Exp $	*/
+/*	$OpenBSD: cpu.h,v 1.35 2023/07/25 18:16:21 cheloha Exp $	*/
 /*	$NetBSD: cpu.h,v 1.41 2006/01/21 04:24:12 uwe Exp $	*/
 
 /*-
@@ -68,6 +68,7 @@ struct cpu_info {
 #endif
 #ifdef GPROF
 	struct gmonparam *ci_gmon;
+	struct clockintr *ci_gmonclock;
 #endif
 
 	int	ci_want_resched;
diff --git a/sys/arch/sh/sh/clock.c b/sys/arch/sh/sh/clock.c
index 409a1833482..2e3a8b62ee3 100644
--- a/sys/arch/sh/sh/clock.c
+++ b/sys/arch/sh/sh/clock.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: clock.c,v 1.14 2023/04/10 04:21:20 jsg Exp $	*/
+/*	$OpenBSD: clock.c,v 1.15 2023/07/25 18:16:21 cheloha Exp $	*/
 /*	$NetBSD: clock.c,v 1.32 2006/09/05 11:09:36 uwe Exp $	*/
 
 /*-
@@ -203,7 +203,6 @@ sh_clock_get_pclock(void)
 void
 setstatclockrate(int newhz)
 {
-	clockintr_setstatclockrate(newhz);
 }
 
 u_int