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  1. 28 6月, 2006 1 次提交
  3. 24 5月, 2006 5 次提交
  5. 19 5月, 2006 5 次提交
  7. 29 4月, 2006 3 次提交
  9. 22 4月, 2006 2 次提交
  11. 04 4月, 2006 1 次提交
  13. 28 3月, 2006 2 次提交
  15. 22 3月, 2006 5 次提交
  17. 24 2月, 2006 1 次提交
    • A
      [PATCH] powerpc: Fix runlatch performance issues · cb2c9b27
      由 Anton Blanchard 提交于 
      The runlatch SPR can take a lot of time to write. My original runlatch
code would set it on every exception entry even though most of the time
this was not required. It would also continually set it in the idle
loop, which is an issue on an SMT capable processor.

Now we cache the runlatch value in a threadinfo bit, and only check for
it in decrementer and hardware interrupt exceptions as well as the idle
loop. Boot on POWER3, POWER5 and iseries, and compile tested on pmac32.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>
      cb2c9b27
  19. 13 1月, 2006 1 次提交
    • D
      [PATCH] powerpc: Remove lppaca structure from the PACA · 3356bb9f
      由 David Gibson 提交于 
      At present the lppaca - the structure shared with the iSeries
hypervisor and phyp - is contained within the PACA, our own low-level
per-cpu structure.  This doesn't have to be so, the patch below
removes it, making a separate array of lppaca structures.

This saves approximately 500*NR_CPUS bytes of image size and kernel
memory, because we don't need aligning gap between the Linux and
hypervisor portions of every PACA.  On the other hand it means an
extra level of dereference in many accesses to the lppaca.

The patch also gets rid of several places where we assign the paca
address to a local variable for no particular reason.
Signed-off-by: NDavid Gibson <dwg@au1.ibm.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>
      3356bb9f
  21. 11 1月, 2006 3 次提交
  23. 09 1月, 2006 1 次提交
  25. 14 11月, 2005 1 次提交
  27. 10 11月, 2005 3 次提交
  29. 09 11月, 2005 2 次提交
    • N
      [PATCH] sched: resched and cpu_idle rework · 64c7c8f8
      由 Nick Piggin 提交于 
      Make some changes to the NEED_RESCHED and POLLING_NRFLAG to reduce
confusion, and make their semantics rigid.  Improves efficiency of
resched_task and some cpu_idle routines.

* In resched_task:
- TIF_NEED_RESCHED is only cleared with the task's runqueue lock held,
  and as we hold it during resched_task, then there is no need for an
  atomic test and set there. The only other time this should be set is
  when the task's quantum expires, in the timer interrupt - this is
  protected against because the rq lock is irq-safe.

- If TIF_NEED_RESCHED is set, then we don't need to do anything. It
  won't get unset until the task get's schedule()d off.

- If we are running on the same CPU as the task we resched, then set
  TIF_NEED_RESCHED and no further action is required.

- If we are running on another CPU, and TIF_POLLING_NRFLAG is *not* set
  after TIF_NEED_RESCHED has been set, then we need to send an IPI.

Using these rules, we are able to remove the test and set operation in
resched_task, and make clear the previously vague semantics of
POLLING_NRFLAG.

* In idle routines:
- Enter cpu_idle with preempt disabled. When the need_resched() condition
  becomes true, explicitly call schedule(). This makes things a bit clearer
  (IMO), but haven't updated all architectures yet.

- Many do a test and clear of TIF_NEED_RESCHED for some reason. According
  to the resched_task rules, this isn't needed (and actually breaks the
  assumption that TIF_NEED_RESCHED is only cleared with the runqueue lock
  held). So remove that. Generally one less locked memory op when switching
  to the idle thread.

- Many idle routines clear TIF_POLLING_NRFLAG, and only set it in the inner
  most polling idle loops. The above resched_task semantics allow it to be
  set until before the last time need_resched() is checked before going into
  a halt requiring interrupt wakeup.

  Many idle routines simply never enter such a halt, and so POLLING_NRFLAG
  can be always left set, completely eliminating resched IPIs when rescheduling
  the idle task.

  POLLING_NRFLAG width can be increased, to reduce the chance of resched IPIs.
Signed-off-by: NNick Piggin <npiggin@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Con Kolivas <kernel@kolivas.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      64c7c8f8
    • N
      [PATCH] sched: disable preempt in idle tasks · 5bfb5d69
      由 Nick Piggin 提交于 
      Run idle threads with preempt disabled.

Also corrected a bugs in arm26's cpu_idle (make it actually call schedule()).
How did it ever work before?

Might fix the CPU hotplugging hang which Nigel Cunningham noted.

We think the bug hits if the idle thread is preempted after checking
need_resched() and before going to sleep, then the CPU offlined.

After calling stop_machine_run, the CPU eventually returns from preemption and
into the idle thread and goes to sleep.  The CPU will continue executing
previous idle and have no chance to call play_dead.

By disabling preemption until we are ready to explicitly schedule, this bug is
fixed and the idle threads generally become more robust.

From: alexs <ashepard@u.washington.edu>

  PPC build fix

From: Yoichi Yuasa <yuasa@hh.iij4u.or.jp>

  MIPS build fix
Signed-off-by: NNick Piggin <npiggin@suse.de>
Signed-off-by: NYoichi Yuasa <yuasa@hh.iij4u.or.jp>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      5bfb5d69
  31. 07 11月, 2005 2 次提交
    • D
      [PATCH] powerpc: Kill ppcdebug · dcad47fc
      由 David Gibson 提交于 
      The ancient ppcdebug/PPCDBG mechanism is now only used in two places.
First, in the hash setup code, one of the bits allows the size of the
hash table to be reduced by a factor of 8 - which would be better
accomplished with a command line option for that purpose.  The other
was a bunch of bus walking related messages in the iSeries code, which
would seem to be insufficient reason to keep the mechanism.

This patch removes the last traces of this mechanism.

Built and booted on iSeries and pSeries POWER5 LPAR (ARCH=powerpc).
Signed-off-by: NDavid Gibson <dwg@au1.ibm.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>
      dcad47fc
    • B
      [PATCH] ppc64: support 64k pages · 3c726f8d
      由 Benjamin Herrenschmidt 提交于 
      Adds a new CONFIG_PPC_64K_PAGES which, when enabled, changes the kernel
base page size to 64K.  The resulting kernel still boots on any
hardware.  On current machines with 4K pages support only, the kernel
will maintain 16 "subpages" for each 64K page transparently.

Note that while real 64K capable HW has been tested, the current patch
will not enable it yet as such hardware is not released yet, and I'm
still verifying with the firmware architects the proper to get the
information from the newer hypervisors.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      3c726f8d
  33. 02 11月, 2005 2 次提交