Commit Graph

84 Commits

Author SHA1 Message Date
Christoph Hellwig
5158e9b521 [POWERPC] spufs: add context switch notification log
There are userspace instrumentation tools that need to monitor spu
context switches. This patch adds a new file called 'switch_log' to
each spufs context directory that can be used to monitor the context
switches.

Context switch in/out and exit from spu_run are monitored after the
file was first opened and can be read from it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
2008-04-30 15:01:54 +10:00
Jeremy Kerr
ce7c191bca [POWERPC] spufs: don't (ab)use SCHED_IDLE
commit 4ef11014 introduced a usage of SCHED_IDLE to detect when
a context is within spu_run.

Instead of SCHED_IDLE (which has other meaning), add a flag to
sched_flags to tell if a context should be running.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
2008-03-11 12:28:02 +11:00
Andre Detsch
2a58aa33da [POWERPC] spufs: fix use time accounting on SPE-overcommit
The spu_runcntl_RW register is restored within spu_restore function.
So, at the end of spu_bind_context, the SPU context is not just loaded,
but running.

This change corrects the state switch to account the time as USER.

Signed-off-by: Andre Detsch <adetsch@br.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
2008-02-29 15:48:55 +11:00
Jeremy Kerr
4ef110141b [POWERPC] spufs: fix scheduler starvation by idle contexts
2.6.25 has a regression where we can starve the scheduler by creating
(N_SPES+1) contexts, then running them one at a time.

The final context will never be run, as the other contexts are loaded on
the SPEs, none of which are repoted as free (ie, spu->alloc_state !=
SPU_FREE), so spu_get_idle() doesn't give us a spu to run on. Because
all of the contexts are stopped, none are descheduled by the scheduler
tick, as spusched_tick returns if spu_stopped(ctx).

This change replaces the spu_stopped() check with checking for SCHED_IDLE
in ctx->policy. We set a context's policy to SCHED_IDLE when we're not
in spu_run(). We also favour SCHED_IDLE contexts when looking for contexts
to unbind, but leave their timeslice intact for later resumption.

This patch fixes the following test in the spufs-testsuite:
  tests/20-scheduler/02-yield-starvation

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
2008-02-19 10:12:02 +11:00
Christoph Hellwig
038200cfdc [POWERPC] spufs: Add marker-based tracing facility
This adds markers two important points in the spufs code and a new
module (sputrace.ko) that allows reading these out through a proc file.

Long-term I'd rather see something like lttng extended to use the spufs
instrumentation, but for now I think this is a good enough quick
solution.  We'll probably want to add various addition event in addition
to that ones I have already.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-02-06 16:26:59 +11:00
Paul Mackerras
9156ad4833 Merge branch 'linux-2.6' 2008-01-24 10:07:21 +11:00
Paul Mackerras
a5a971129c [POWERPC] Fix build failure on Cell when CONFIG_SPU_FS=y
Commit aed3a8c9bb introduced a
definition of notify_spus_active in .../cell/spu_syscalls.c, and
another definition under #ifndef MODULE in .../cell/spufs/sched.c.
The latter is not necessary and causes the build to fail when
CONFIG_SPU_FS=y, so this removes it.  It also removes the export
of do_notify_spus_active, which is unnecessary.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Jeremy Kerr <jk@ozlabs.org>
2008-01-02 15:56:30 +11:00
Bob Nelson
aed3a8c9bb [POWERPC] Oprofile: Remove dependency on spufs module
This removes an OProfile dependency on the spufs module.  This
dependency was causing a problem for multiplatform systems that are
built with support for Oprofile on Cell but try to load the oprofile
module on a non-Cell system.

Signed-off-by: Bob Nelson <rrnelson@us.ibm.com>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Acked-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-12-28 15:07:52 +11:00
Aegis Lin
90608a2928 [POWERPC] spufs: Use separate timer for /proc/spu_loadavg calculation
The original spusched_timer was designed to take effect only when
a context is waiting in the runqueue.

This change adds an additional lower-freq timer has been added to
purely handle the spu_load updates. The new timer will be triggered
per LOAD_FREQ ticks.

Signed-off-by: Aegis Lin <aegislin@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-12-21 19:46:21 +11:00
Christoph Hellwig
c9101bdb1b [POWERPC] spufs: make state_mutex interruptible
Make most places that use spu_acquire/spu_acquire_saved interruptible,
this allows getting out of the spufs code when e.g. pressing ctrl+c.
There are a few places where we get called e.g. from spufs teardown
routines were we can't simply err out so these are left with a comment.
For now I've also not touched the poll routines because it's open what
libspe would expect in terms of interrupted system calls.

Acked-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-12-21 19:46:21 +11:00
Luke Browning
e65c2f6fce [POWERPC] spufs: decouple spu scheduler from spufs_spu_run (asynchronous scheduling)
Change spufs_spu_run so that the context is queued directly to the
scheduler and the controlling thread advances directly to spufs_wait()
for spe errors and exceptions.

nosched contexts are treated the same as before.

Fixes from Christoph Hellwig <hch@lst.de>

Signed-off-by: Luke Browning <lukebr@linux.vnet.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-12-21 19:46:21 +11:00
Luke Browning
b192541b39 [POWERPC] spufs: spu_find_victim may choose wrong victim
Need to re-check priority after dropping lock.  Otherwise, a
more favored context may be preempted.

Signed-off-by: Luke Browning <lukebr@linux.vnet.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-12-21 19:46:20 +11:00
Luke Browning
91569531d1 [POWERPC] spufs: reorganize spu_run_init
This cleans up spu_run_init so that it does all of the spu
initialization for spufs_run_spu.  It initializes the spu context as
much as possible before it activates the spu and writes the runcntl
register.

Signed-off-by: Luke Browning <lukebr@linux.vnet.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-12-21 19:46:20 +11:00
Jeremy Kerr
d6ad39bc53 [POWERPC] spufs: rework class 0 and 1 interrupt handling
Based on original patches from
 Arnd Bergmann <arnd.bergman@de.ibm.com>; and
 Luke Browning <lukebr@linux.vnet.ibm.com>

Currently, spu contexts need to be loaded to the SPU in order to take
class 0 and class 1 exceptions.

This change makes the actual interrupt-handlers much simpler (ie,
set the exception information in the context save area), and defers the
handling code to the spufs_handle_class[01] functions, called from
spufs_run_spu.

This should improve the concurrency of the spu scheduling leading to
greater SPU utilization when SPUs are overcommited.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-12-21 19:46:20 +11:00
Arnd Bergmann
33bfd7a738 [POWERPC] spufs: block fault handlers in spu_acquire_runnable
This change disables the logic that faults-in spu contexts under the
covers from the page fault handler.  When a fault requires a runnable
context, the handler will block until the context is scheduled by
other means.

Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-12-21 19:46:19 +11:00
Jeremy Kerr
7cd58e4381 [POWERPC] spufs: move fault, lscsa_alloc and switch code to spufs module
Currently, part of the spufs code (switch.o, lscsa_alloc.o and fault.o)
is compiled directly into the kernel.

This change moves these components of spufs into the kernel.

The lscsa and switch objects are fairly straightforward to move in.

For the fault.o module, we split the fault-handling code into two
parts: a/p/p/c/spu_fault.c and a/p/p/c/spufs/fault.c. The former is for
the in-kernel spu_handle_mm_fault function, and we move the rest of the
fault-handling code into spufs.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-12-21 19:46:19 +11:00
Julio M. Merino Vidal
9b1d21f858 [POWERPC] spufs: fix typos in sched.c comments
Fix a few typos in the spufs scheduler comments

Signed-off-by: Julio M. Merino Vidal <jmerino@ac.upc.edu>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-12-21 19:46:18 +11:00
Paul Mackerras
0ce49a3945 Merge branch 'linux-2.6' 2007-09-20 10:09:27 +10:00
Christoph Hellwig
c0e7b4aa1c [POWERPC] spusched: Fix null pointer dereference in find_victim
find_victim can dereference a NULL pointer when iterating over the list
of victim spus because list_mutex only guarantees spu->ct to be stable,
but of course not to be non-NULL.

Also fix find_victim to not call spu_unbind_context without list_mutex
because that violates the above guarantee.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-09-19 15:26:29 +10:00
Andre Detsch
36ddbb1380 [POWERPC] spufs: Fix race condition on gang->aff_ref_spu
Affinity reference point location (gang->aff_ref_spu) is reset
when the whole gang is descheduled. However, the last member of
a gang can be descheduled while we are trying to schedule another
member of the gang. This was leading to a race condition, and
the code was using gang->aff_ref_spu in an unsafe manner.

By holding the gang->aff_mutex a little bit longer, and increment
gang->aff_sched_count (which controls when gang->aff_ref_spu
should be reset) a little bit earlier, the problem is fixed.

Signed-off-by: Andre Detsch <adetsch@br.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-09-19 15:12:16 +10:00
Andre Detsch
683e3ab2b5 [POWERPC] spufs: Fix affinity after introduction of node_allowed() calls
This patch fixes affinity reference point placement, which was not being
done in some situations, after the introduction of node_allowed() calls.

The previously used parameter, 'ctx', is just the iterator of the
previous list_for_each_entry_reverse loop, and its value might be
invalid at the end of the loop. Also, the right context to seek
for information when defining the reference ctx location
_is_ the reference ctx.

Signed-off-by: Andre Detsch <adetsch@br.ibm.com>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-08-03 19:18:10 +10:00
Masato Noguchi
6f6a6dc0c8 [POWERPC] spufs: Fix incorrect initialization of cbe_spu_info.spus
We currently initialize cbe_spu_info[].spus in both init_spu_base and
spu_sched_init. The initialise in spu_sched_init clears the SPU list,
so we end up with no physical SPUs. Because of this, the spu_run
syscall will block forever.

This change removes the unnecessary initialization in spu_sched_init.

Signed-off-by: Masato Noguchi <Masato.Noguchi@jp.sony.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-07-26 16:17:55 +10:00
Christoph Hellwig
486acd4850 [CELL] spufs: rework list management and associated locking
This sorts out the various lists and related locks in the spu code.

In detail:

 - the per-node free_spus and active_list are gone.  Instead struct spu
   gained an alloc_state member telling whether the spu is free or not
 - the per-node spus array is now locked by a per-node mutex, which
   takes over from the global spu_lock and the per-node active_mutex
 - the spu_alloc* and spu_free function are gone as the state change is
   now done inline in the spufs code.  This allows some more sharing of
   code for the affinity vs normal case and more efficient locking
 - some little refactoring in the affinity code for this locking scheme

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
2007-07-20 21:42:28 +02:00
Bob Nelson
1474855d08 [CELL] oprofile: add support to OProfile for profiling CELL BE SPUs
From: Maynard Johnson <mpjohn@us.ibm.com>

This patch updates the existing arch/powerpc/oprofile/op_model_cell.c
to add in the SPU profiling capabilities.  In addition, a 'cell' subdirectory
was added to arch/powerpc/oprofile to hold Cell-specific SPU profiling code.
Exports spu_set_profile_private_kref and spu_get_profile_private_kref which
are used by OProfile to store private profile information in spufs data
structures.

Also incorporated several fixes from other patches (rrn).  Check pointer
returned from kzalloc.  Eliminated unnecessary cast.  Better error
handling and cleanup in the related area.  64-bit unsigned long parameter
was being demoted to 32-bit unsigned int and eventually promoted back to
unsigned long.

Signed-off-by: Carl Love <carll@us.ibm.com>
Signed-off-by: Maynard Johnson <mpjohn@us.ibm.com>
Signed-off-by: Bob Nelson <rrnelson@us.ibm.com>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Acked-by: Paul Mackerras <paulus@samba.org>
2007-07-20 21:42:24 +02:00
Bob Nelson
36aaccc1e9 [CELL] oprofile: enable SPU switch notification to detect currently active SPU tasks
From: Maynard Johnson <mpjohn@us.ibm.com>

This patch adds to the capability of spu_switch_event_register so that
the caller is also notified of currently active SPU tasks.
Exports spu_switch_event_register and spu_switch_event_unregister so
that OProfile can get access to the notifications provided.

Signed-off-by: Maynard Johnson <mpjohn@us.ibm.com>
Signed-off-by: Carl Love <carll@us.ibm.com>
Signed-off-by: Bob Nelson <rrnelson@us.ibm.com>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Acked-by: Paul Mackerras <paulus@samba.org>
2007-07-20 21:42:20 +02:00
Arnd Bergmann
cbc23d3e7c [CELL] spufs: integration of SPE affinity with the scheduller
This patch makes the scheduller honor affinity information for each
context being scheduled. If the context has no affinity information,
behaviour is unchanged. If there are affinity information, context is
schedulled to be run on the exact spu recommended by the affinity
placement algorithm.

Signed-off-by: Andre Detsch <adetsch@br.ibm.com>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
2007-07-20 21:42:18 +02:00
Arnd Bergmann
c5fc8d2a92 [CELL] cell: add placement computation for scheduling of affinity contexts
This patch provides the spu affinity placement logic for the spufs scheduler.
Each time a gang is going to be scheduled, the placement of a reference
context is defined. The placement of all other contexts with affinity from
the gang is defined based on this reference context location and on a
precomputed displacement offset.

Signed-off-by: Andre Detsch <adetsch@br.ibm.com>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
2007-07-20 21:42:17 +02:00
Arnd Bergmann
aa6d5b2025 [CELL] cell: add per BE structure with info about its SPUs
Addition of a spufs-global "cbe_info" array. Each entry contains information
about one Cell/B.E. node, namelly:
* list of spus (both free and busy spus are in this list);
* list of free spus (replacing the static spu_list from spu_base.c)
* number of spus;
* number of reserved (non scheduleable) spus.

SPE affinity implementation actually requires only access to one spu per
BE node (since it implements its own pointer to walk through the other spus
of the ring) and the number of scheduleable spus (n_spus - non_sched_spus)
However having this more general structure can be useful for other
functionalities, concentrating per-cbe statistics / data.

Signed-off-by: Andre Detsch <adetsch@br.ibm.com>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
2007-07-20 21:42:11 +02:00
Masato Noguchi
7e90b74967 [CELL] spufs: use find_first_bit() instead of sched_find_first_bit()
spu_sched->bitmap has MAX_PRIO(=140) width in bits.However, since
ff80a77f20, sched_find_first_bit()
only supports 100-bit bitmaps.

Thus, spu_sched->bitmap should be treated by generic find_first_bit().

Signed-off-by: Masato Noguchi <Masato.Noguchi@jp.sony.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
2007-07-20 21:42:07 +02:00
Andre Detsch
27ec41d3a1 [CELL] spufs: add spu stats in sysfs and ctx stat file in spufs
This patch exports per-context statistics in spufs as long as spu
statistics in sysfs.

It was formed by merging:
"spufs: add spu stats in sysfs"   From: Christoph Hellwig
"spufs: add stat file to spufs"   From: Christoph Hellwig
"spufs: fix libassist accounting" From: Jeremy Kerr
"spusched: fix spu utilization statistics" From: Luke Browning
And some adjustments by myself, after suggestions on cbe-oss-dev.

Having separate patches was making the review process harder
than it should, as we end up integrating spus and ctx statistics
accounting much more than it was on the first implementation.

Signed-off-by: Andre Detsch <adetsch@br.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
2007-07-20 21:41:50 +02:00
Jeremy Kerr
e840cfe681 [CELL] spufs: Remove spurious WARN_ON for spu_deactivate for NOSCHED contexts
In 6cbf93960e64f313f6e247cbca7afaa50e3ee2c we added a WARN_ON for
calling spu_deactivate on contexts created with the SPU_CREATE_NOSCHED
flag. However, all NOSCHED contexts will need to be deactivated when
the context is destroyed, so this gives a spurious warning when any
NOSCHED context is closed.

This change removes the WARN_ON.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
2007-07-20 21:41:49 +02:00
Sebastian Siewior
d145031755 [CELL] spufs: remove section mismatch warning
WARNING: arch/powerpc/platforms/cell/spufs/spufs.o(.init.text+0x158): Section
mismatch: reference to .exit.text:.spu_sched_exit (between '.init_module' and
'.spu_sched_init')

was introduced by c99c1994a2
This patch removes the warning.

Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
2007-07-20 21:41:46 +02:00
Christoph Hellwig
fe2f896d67 [POWERPC] spufs: Add spu stats in sysfs
Export spu statistics in sysfs.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-07-03 15:24:46 +10:00
Christoph Hellwig
27449971e6 [POWERPC] spusched: Fix runqueue corruption
spu_activate can be called from multiple threads at the same time on
behalf of the same spu context.  We need to make sure to only add it
once to avoid runqueue corruption.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-07-03 15:24:46 +10:00
Christoph Hellwig
c77239b8be [POWERPC] spusched: Disable tick when not needed
Only enable the scheduler tick if we have any context waiting to be
scheduled.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-07-03 15:24:46 +10:00
Christoph Hellwig
e9f8a0b65a [POWERPC] spufs: Add stat file to spufs
Export per-context statistics in spufs.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-07-03 15:24:46 +10:00
Christoph Hellwig
65de66f0b8 [POWERPC] spufs: Implement /proc/spu_loadavg
Provide load average information for spu context.  The format
is identical to /proc/loadavg, which is also where a lot of code
and concepts is borrowed from.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-07-03 15:24:46 +10:00
Christoph Hellwig
476273adc7 [POWERPC] spufs: Add tid file
The new tid file contains the ID of the thread currently running the
context, if any.  This is used so that the new spu-top and spu-ps
tools can find the thread in /proc.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-07-03 15:24:45 +10:00
Jeremy Kerr
7022543ee4 [POWERPC] spufs: Trivial whitespace fixes
Remove redundant whitespace in arch/powerpc/platforms/cell/spufs/

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-07-03 15:24:45 +10:00
Christoph Hellwig
df09cf3e2c [POWERPC] spusched: No preemption for nosched contexts
And last but not least we need to make sure the scheduler tick never
preempts a nosched context.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-07-03 15:24:45 +10:00
Christoph Hellwig
46cbf93960 [POWERPC] spusched: Catch nosched contexts in spu_deactivate
spu_deactivate should never be called for nosched contets.  Put in
a check so we can print a stacktrace and exit early in case it
happes erroneously.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-07-03 15:24:45 +10:00
Christoph Hellwig
ea1ae5949d [POWERPC] spusched: fix cpu/node binding
Add a cpus_allowed allowed filed to struct spu_context so that we always
use the cpu mask of the owning thread instead of the one happening to
call into the scheduler.  Also use this information in
grab_runnable_context to avoid spurious wakeups.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-07-03 15:24:45 +10:00
Christoph Hellwig
2cf2b3b49f [POWERPC] spusched: Update scheduling paramters on every spu_run
Update scheduling information on every spu_run to allow for setting
threads to realtime priority just before running them.  This requires
some slightly ugly code in spufs_run_spu because we can just update
the information unlocked if the spu is not runnable, but we need to
acquire the active_mutex when it is runnable to protect against
find_victim.  This locking scheme requires opencoding
spu_acquire_runnable in spufs_run_spu which actually is a nice cleanup
all by itself.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-07-03 15:24:45 +10:00
Jeremy Kerr
f3f59bec0c [POWERPC] spusched: Print out scheduling tunables with DEBUG
Print out a few scheduler tuning parameters when we've compiled
with DEBUG defined.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-07-03 15:24:45 +10:00
Jeremy Kerr
60e2423933 [POWERPC] spusched: Fix timeslice calculations
The current timeslice code mixes 'jiffies' up with 'spesched ticks'. This
change correctly defines the number of time slices each SPE contexts is
given, and clarifies the comment.

This brings the default timeslice for SPE contexts into a reasonable
range.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-07-03 15:24:44 +10:00
Christoph Hellwig
fe443ef2ac [POWERPC] spusched: Dynamic timeslicing for SCHED_OTHER
Enable preemptive scheduling for non-RT contexts.

We use the same algorithms as the CPU scheduler to calculate the time
slice length, and for now we also use the same timeslice length as the
CPU scheduler. This might be not enough for good performance and can be
changed after some benchmarking.

Note that currently we do not boost the priority for contexts waiting
on the runqueue for a long time, so contexts with a higher nice value
could starve ones with less priority.  This could easily be fixed once
the rework of the spu lists that Luke and I discussed is done.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-07-03 15:24:44 +10:00
Christoph Hellwig
3790180220 [POWERPC] spusched: Switch from workqueues to kthread + timer tick
Get rid of the scheduler workqueues that complicated things a lot to
a dedicated spu scheduler thread that gets woken by a traditional
scheduler tick.  By default this scheduler tick runs a HZ * 10, aka
one spu scheduler tick for every 10 cpu ticks.

Currently the tick is not disabled when we have less context than
available spus, but I will implement this later.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-07-03 15:24:44 +10:00
Christoph Hellwig
e5c0b9ec53 [POWERPC] spufs: Don't yield nosched context
Nosched context sould never be scheduled out, thus we must not
deactivate them in spu_yield ever.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-06-07 11:44:40 +10:00
Christoph Hellwig
bb5db29aa0 [POWERPC] spufs scheduler: Fix wakeup races
Fix the race between checking for contexts on the runqueue and actually
waking them in spu_deactive and spu_yield.

The guts of spu_reschedule are split into a new helper called
grab_runnable_context which shows if there is a runnable thread below
a specified priority and if yes removes if from the runqueue and uses
it.  This function is used by the new __spu_deactivate hepler shared
by preemption and spu_yield to grab a new context before deactivating
a specified priority and if yes removes if from the runqueue and uses
it.  This function is used by the new __spu_deactivate hepler shared
by preemption and spu_yield to grab a new context before deactivating
the old one.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-06-07 11:44:39 +10:00
Randy Dunlap
e63340ae6b header cleaning: don't include smp_lock.h when not used
Remove includes of <linux/smp_lock.h> where it is not used/needed.
Suggested by Al Viro.

Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc,
sparc64, and arm (all 59 defconfigs).

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08 11:15:07 -07:00