My apologies for taking so long to respond, but I've made the patch
(attached). If no one is aginst me, I'm going to commit it next sunday.
I will change some device drivers which use power hook appropriately.

Takemura

> -----Original Message-----
> From: augustss@augustsson.net [mailto:augustss@augustsson.net]On
> Behalf Of Lennart Augustsson
> Sent: Monday, September 11, 2000 1:26 AM
> Subject: Re: power hook and spl level
>
> TAKEMURA Shin wrote:
> > I propose introducing new power events which are
> > processed in lower level like below:
> >
> >         dopowerhooks(PWR_SOFTSUSPEND);
> >         apm_spl = splhigh();
> >         dopowerhooks(PWR_SUSPEND);
> >         /* suspned... */
> >         dopowerhooks(PWR_RESUME);
> >         splx(apm_spl);
> >
> >         dopowerhooks(PWR_SOFTRESUME);
>
> Unless someone has a better idea, I think this looks good.

Index: share/man/man9/powerhook_establish.9
===================================================================
RCS file: /cvsroot/sharesrc/share/man/man9/powerhook_establish.9,v
retrieving revision 1.1
diff -c -r1.1 powerhook_establish.9
*** share/man/man9/powerhook_establish.9        1999/12/06 14:50:02     1.1
--- share/man/man9/powerhook_establish.9        2000/11/24 02:06:14
***************
*** 80,89 ****
--- 80,95 ----
  resume.  The reason is reflected in the
  .Fa why
  argument and the values
+ .Dv PWR_SOFTSUSPEND ,
  .Dv PWR_SUSPEND ,
+ .Dv PWR_SOFTSTANDBY ,
  .Dv PWR_STANDBY ,
+ .Dv PWR_SOFTRESUME ,
  and
  .Dv PWR_RESUME .
+ It calls with PWR_SOFTxxx in the normal priority level while the other
+ callings are protected with
+ .Xr splhigh 9 .
  At suspend the system is going to lose (almost) all power, standby retains
  some power (e.g., minimal power to USB devices), and at resume power is
  back to normal.
Index: sys/arch/i386/i386/apm.c
===================================================================
RCS file: /cvsroot/syssrc/sys/arch/i386/i386/apm.c,v
retrieving revision 1.55
diff -c -r1.55 apm.c
*** sys/arch/i386/i386/apm.c    2000/11/15 01:59:35     1.55
--- sys/arch/i386/i386/apm.c    2000/11/24 02:06:17
***************
*** 401,406 ****
--- 401,408 ----
        }
        sc->sc_power_state = PWR_SUSPEND;

+       dopowerhooks(PWR_SOFTSUSPEND);
+
        apm_spl = splhigh();

        dopowerhooks(PWR_SUSPEND);
***************
*** 423,428 ****
--- 425,432 ----
        }
        sc->sc_power_state = PWR_STANDBY;

+       dopowerhooks(PWR_SOFTSTANDBY);
+
        apm_spl = splhigh();

        dopowerhooks(PWR_STANDBY);
***************
*** 455,460 ****
--- 459,466 ----
        dopowerhooks(PWR_RESUME);

        splx(apm_spl);
+
+       dopowerhooks(PWR_SOFTRESUME);

        apm_record_event(sc, regs->BX);
  }
Index: sys/kern/kern_subr.c
===================================================================
RCS file: /cvsroot/syssrc/sys/kern/kern_subr.c,v
retrieving revision 1.72
diff -c -r1.72 kern_subr.c
*** sys/kern/kern_subr.c        2000/11/08 14:25:24     1.72
--- sys/kern/kern_subr.c        2000/11/24 02:06:20
***************
*** 426,432 ****
  {
        struct powerhook_desc *dp;

!       if (why == PWR_RESUME) {
                CIRCLEQ_FOREACH_REVERSE(dp, &powerhook_list, sfd_list) {
                        (*dp->sfd_fn)(why, dp->sfd_arg);
                }
--- 426,432 ----
  {
        struct powerhook_desc *dp;

!       if (why == PWR_RESUME || why == PWR_SOFTRESUME) {
                CIRCLEQ_FOREACH_REVERSE(dp, &powerhook_list, sfd_list) {
                        (*dp->sfd_fn)(why, dp->sfd_arg);
                }
<< END