flags with interrupts disabled to see if we should call ast() during
doreti. This was mostly submitted by Bruce, but his original patch did
the looping in ast() in assembly rather than in the ast() function itself.
Once we've actually called into the ast() function, it's cheaper to just
loop inside the function rather than returning from the function,
performing the check, and then calling the function again. However, we
can optimize the first check to avoid calling the function at all.
Other architectures may choose to implement this optimization if they
wish but it is not required for correct operation.
Submitted by: bde
the process of exiting the kernel. The ast() function now loops as long
as the PS_ASTPENDING or PS_NEEDRESCHED flags are set. It returns with
preemption disabled so that any further AST's that arrive via an
interrupt will be delayed until the low-level MD code returns to user
mode.
- Use u_int's to store the tick counts for profiling purposes so that we
do not need sched_lock just to read p_sticks. This also closes a
problem where the call to addupc_task() could screw up the arithmetic
due to non-atomic reads of p_sticks.
- Axe need_proftick(), aston(), astoff(), astpending(), need_resched(),
clear_resched(), and resched_wanted() in favor of direct bit operations
on p_sflag.
- Fix up locking with sched_lock some. In addupc_intr(), use sched_lock
to ensure pr_addr and pr_ticks are updated atomically with setting
PS_OWEUPC. In ast() we clear pr_ticks atomically with clearing
PS_OWEUPC. We also do not grab the lock just to test a flag.
- Simplify the handling of Giant in ast() slightly.
Reviewed by: bde (mostly)
a time using the ogetdirentries() compatibility syscall. This is a
hack to ensure that rediculous values don't get passed to MALLOC().
Reviewed by: kris
for endtsleep() to be executing when msleep() resumed, for endtsleep()
to spin on sched_lock long enough for the other process to loop on
msleep() and sleep again resulting in endtsleep() waking up the "wrong"
msleep.
Obtained from: BSD/OS
removing the callout entry, return 1. If callout_stop() fails to remove
the callout entry because it is currently executing or has already been
executed, then the function returns 0. The idea was obtained from BSD/OS,
however, BSD/OS changed untimeout(), and I've just changed callout_stop()
to be more conservative.
Obtained from: BSD/OS
Backout previous revision. We should not expand plain text xrefs if
they appear in the literal text, e.g. in the error or warning message
of the library function. (Submitted by: bde)
Moved "out of memory" from warning to errors section.
