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  1. Sep 05, 2008
    • Jeremy Kerr's avatar
      powerpc/spufs: Fix race for a free SPU · b65fe035
      Jeremy Kerr authored 
      

We currently have a race for a free SPE. With one thread doing a
spu_yield(), and another doing a spu_activate():

thread 1				thread 2
spu_yield(oldctx)			spu_activate(ctx)
  __spu_deactivate(oldctx)
  spu_unschedule(oldctx, spu)
  spu->alloc_state = SPU_FREE
					spu = spu_get_idle(ctx)
					    - searches for a SPE in
					      state SPU_FREE, gets
					      the context just
					      freed by thread 1
					spu_schedule(ctx, spu)
					  spu->alloc_state = SPU_USED
spu_schedule(newctx, spu)
  - assumes spu is still free
  - tries to schedule context on
    already-used spu

This change introduces a 'free_spu' flag to spu_unschedule, to indicate
whether or not the function should free the spu after descheduling the
context. We only set this flag if we're not going to re-schedule
another context on this SPU.

Add a comment to document this behaviour.

Signed-off-by: default avatarJeremy Kerr <jk@ozlabs.org>
      b65fe035
    • Jeremy Kerr's avatar
      powerpc/spufs: Fix multiple get_spu_context() · 9f43e391
      Jeremy Kerr authored 
      

Commit 8d5636fb introduced a reference
count on SPU contexts during find_victim, but this may cause a leak in
the reference count if we later find a better contender for a context to
unschedule.

Change the reference to after we've found our victim context, so we
don't do the extra get_spu_context().

Signed-off-by: default avatarJeremy Kerr <jk@ozlabs.org>
      9f43e391
  3. Aug 19, 2008
  5. Aug 14, 2008
  7. Aug 13, 2008
    • Jeremy Kerr's avatar
      powerpc/spufs: fix npc setting for NOSCHED contexts · d9dd421f
      Jeremy Kerr authored 
      

Currently, spu_run ignores the npc argument for contexts created with
SPU_CREATE_NOSCHED. While this is correct for isolated contexts,
there's no need to enforce the npc restriction on non-isolated NOSCHED
contexts.

This means that NOSCHED contexts can only ever run with an entry point
of 0x0.

This change to spu_run_init allows setting of the npc (and, while we're
at it, the privcntl) for non-isolated NOSCHED contexts. This allows
us to run NOSCHED contexts from any entry point.

Signed-off-by: default avatarJeremy Kerr <jk@ozlabs.org>
      d9dd421f
  9. Jul 30, 2008
  11. Jul 26, 2008
    • Alexey Dobriyan's avatar
      SL*B: drop kmem cache argument from constructor · 51cc5068
      Alexey Dobriyan authored 
      

Kmem cache passed to constructor is only needed for constructors that are
themselves multiplexeres.  Nobody uses this "feature", nor does anybody uses
passed kmem cache in non-trivial way, so pass only pointer to object.

Non-trivial places are:
	arch/powerpc/mm/init_64.c
	arch/powerpc/mm/hugetlbpage.c

This is flag day, yes.

Signed-off-by: default avatarAlexey Dobriyan <adobriyan@gmail.com>
Acked-by: default avatarPekka Enberg <penberg@cs.helsinki.fi>
Acked-by: default avatarChristoph Lameter <cl@linux-foundation.org>
Cc: Jon Tollefson <kniht@linux.vnet.ibm.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Matt Mackall <mpm@selenic.com>
[akpm@linux-foundation.org: fix arch/powerpc/mm/hugetlbpage.c]
[akpm@linux-foundation.org: fix mm/slab.c]
[akpm@linux-foundation.org: fix ubifs]
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      51cc5068
    • FUJITA Tomonori's avatar
      dma-mapping: add the device argument to dma_mapping_error() · 8d8bb39b
      FUJITA Tomonori authored 
      Add per-device dma_mapping_ops support for CONFIG_X86_64 as POWER
architecture does:

This enables us to cleanly fix the Calgary IOMMU issue that some devices
are not behind the IOMMU (http://lkml.org/lkml/2008/5/8/423

).

I think that per-device dma_mapping_ops support would be also helpful for
KVM people to support PCI passthrough but Andi thinks that this makes it
difficult to support the PCI passthrough (see the above thread).  So I
CC'ed this to KVM camp.  Comments are appreciated.

A pointer to dma_mapping_ops to struct dev_archdata is added.  If the
pointer is non NULL, DMA operations in asm/dma-mapping.h use it.  If it's
NULL, the system-wide dma_ops pointer is used as before.

If it's useful for KVM people, I plan to implement a mechanism to register
a hook called when a new pci (or dma capable) device is created (it works
with hot plugging).  It enables IOMMUs to set up an appropriate
dma_mapping_ops per device.

The major obstacle is that dma_mapping_error doesn't take a pointer to the
device unlike other DMA operations.  So x86 can't have dma_mapping_ops per
device.  Note all the POWER IOMMUs use the same dma_mapping_error function
so this is not a problem for POWER but x86 IOMMUs use different
dma_mapping_error functions.

The first patch adds the device argument to dma_mapping_error.  The patch
is trivial but large since it touches lots of drivers and dma-mapping.h in
all the architecture.

This patch:

dma_mapping_error() doesn't take a pointer to the device unlike other DMA
operations.  So we can't have dma_mapping_ops per device.

Note that POWER already has dma_mapping_ops per device but all the POWER
IOMMUs use the same dma_mapping_error function.  x86 IOMMUs use device
argument.

[akpm@linux-foundation.org: fix sge]
[akpm@linux-foundation.org: fix svc_rdma]
[akpm@linux-foundation.org: build fix]
[akpm@linux-foundation.org: fix bnx2x]
[akpm@linux-foundation.org: fix s2io]
[akpm@linux-foundation.org: fix pasemi_mac]
[akpm@linux-foundation.org: fix sdhci]
[akpm@linux-foundation.org: build fix]
[akpm@linux-foundation.org: fix sparc]
[akpm@linux-foundation.org: fix ibmvscsi]
Signed-off-by: default avatarFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Muli Ben-Yehuda <muli@il.ibm.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Avi Kivity <avi@qumranet.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      8d8bb39b
  13. Jul 25, 2008
    • Robert Jennings's avatar
      powerpc/pseries: iommu enablement for CMO · 6490c490
      Robert Jennings authored 
      

To support Cooperative Memory Overcommitment (CMO), we need to check
for failure from some of the tce hcalls.

These changes for the pseries platform affect the powerpc architecture;
patches for the other affected platforms are included in this patch.

pSeries platform IOMMU code changes:
 * platform TCE functions must handle H_NOT_ENOUGH_RESOURCES errors and
   return an error.

Architecture IOMMU code changes:
 * Calls to ppc_md.tce_build need to check return values and return
   DMA_MAPPING_ERROR for transient errors.

Architecture changes:
 * struct machdep_calls for tce_build*_pSeriesLP functions need to change
   to indicate failure.
 * all other platforms will need updates to iommu functions to match the new
   calling semantics; they will return 0 on success.  The other platforms
   default configs have been built, but no further testing was performed.

Signed-off-by: default avatarRobert Jennings <rcj@linux.vnet.ibm.com>
Acked-by: default avatarOlof Johansson <olof@lixom.net>
Acked-by: default avatarPaul Mackerras <paulus@samba.org>
Signed-off-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
      6490c490
    • Mark Nelson's avatar
      powerpc/cell: Fixed IOMMU mapping uses weak ordering for a pcie endpoint · 7886250e
      Mark Nelson authored 
      

At the moment the fixed mapping is by default strongly ordered (the
iommu_fixed=weak boot option must be used to make the fixed mapping weakly
ordered). If we're on a setup where the southbridge is being used in
endpoint mode (triblade and CAB boards) the default should be a weakly
ordered fixed mapping.

This adds a check so that if a node of type pcie-endpoint can be found in
the device tree the fixed mapping is set to be weak by default (but can be
overridden using iommu_fixed=strong).

Signed-off-by: default avatarMark Nelson <markn@au1.ibm.com>
Acked-by: default avatarArnd Bergmann <arnd@arndb.de>
Signed-off-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
      7886250e
  15. Jul 24, 2008
  17. Jul 22, 2008
  19. Jul 15, 2008
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  25. Jun 26, 2008
  27. Jun 16, 2008
  29. Jun 09, 2008
  31. Jun 04, 2008
  33. May 23, 2008
    • Michael Ellerman's avatar
      [POWERPC] Add debugging trigger to Axon MSI code · 72cac213
      Michael Ellerman authored 
      

This adds some debugging code to the Axon MSI driver.  It creates a
file per MSIC in /sys/kernel/debug/powerpc, which allows the user to
trigger a fake MSI interrupt by writing to the file.

This can be used to test some of the MSI generation path.  In
particular, that the MSIC recognises a write to the MSI address,
generates an interrupt and writes the MSI packet into the ring buffer.

All the code is inside #ifdef DEBUG so it causes no harm unless it's
enabled.

Signed-off-by: default avatarMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
      72cac213