Commit Graph

56 Commits

Author SHA1 Message Date
John Baldwin
f6a0af8015 Idle processes are always runnable, so let them state at SRUN. 2000-09-15 19:49:48 +00:00
John Baldwin
4a6404dfc1 Fix some printf format string warnings due to sizeof(int) != sizeof(long) on
the alpha.
2000-09-11 23:55:10 +00:00
Jason Evans
0384fff8c5 Major update to the way synchronization is done in the kernel. Highlights
include:

* Mutual exclusion is used instead of spl*().  See mutex(9).  (Note: The
  alpha port is still in transition and currently uses both.)

* Per-CPU idle processes.

* Interrupts are run in their own separate kernel threads and can be
  preempted (i386 only).

Partially contributed by:	BSDi (BSD/OS)
Submissions by (at least):	cp, dfr, dillon, grog, jake, jhb, sheldonh
2000-09-07 01:33:02 +00:00
Matthew Dillon
36e9f877df Commit major SMP cleanups and move the BGL (big giant lock) in the
syscall path inward.  A system call may select whether it needs the MP
    lock or not (the default being that it does need it).

    A great deal of conditional SMP code for various deadended experiments
    has been removed.  'cil' and 'cml' have been removed entirely, and the
    locking around the cpl has been removed.  The conditional
    separately-locked fast-interrupt code has been removed, meaning that
    interrupts must hold the CPL now (but they pretty much had to anyway).
    Another reason for doing this is that the original separate-lock for
    interrupts just doesn't apply to the interrupt thread mechanism being
    contemplated.

    Modifications to the cpl may now ONLY occur while holding the MP
    lock.  For example, if an otherwise MP safe syscall needs to mess with
    the cpl, it must hold the MP lock for the duration and must (as usual)
    save/restore the cpl in a nested fashion.

    This is precursor work for the real meat coming later: avoiding having
    to hold the MP lock for common syscalls and I/O's and interrupt threads.
    It is expected that the spl mechanisms and new interrupt threading
    mechanisms will be able to run in tandem, allowing a slow piecemeal
    transition to occur.

    This patch should result in a moderate performance improvement due to
    the considerable amount of code that has been removed from the critical
    path, especially the simplification of the spl*() calls.  The real
    performance gains will come later.

Approved by: jkh
Reviewed by: current, bde (exception.s)
Some work taken from: luoqi's patch
2000-03-28 07:16:37 +00:00
Peter Wemm
42cef09ba2 Fix a typo and a bug.
- One RTP_PRIO_REALTIME was meant to be RTP_PRIO_IDLE.
- RTP_PRIO_FIFO was not handled.
- Move the usual case first for setrunqueue() etc.
1999-08-19 16:06:08 +00:00
Peter Wemm
dba6c5a6f9 Extract the next runnable process selection out of cpu_switch() into a
fairly machine independent C routine.  gcc actually does a pretty good
job of this.

Reviewed by:	msmith (in principle)
1999-08-19 00:06:53 +00:00