linux-toradex.git/arch/sparc, branch v3.9.2

sparc64: Fix missing put_cpu_var() in tlb_batch_add_one() when not batching.

2013-04-24T23:52:18+00:00

Reported-by: Meelis Roos 
Signed-off-by: David S. Miller

sparc64: Fix race in TLB batch processing.

2013-04-19T21:26:26+00:00

As reported by Dave Kleikamp, when we emit cross calls to do batched
TLB flush processing we have a race because we do not synchronize on
the sibling cpus completing the cross call.

So meanwhile the TLB batch can be reset (tb->tlb_nr set to zero, etc.)
and either flushes are missed or flushes will flush the wrong
addresses.

Fix this by using generic infrastructure to synchonize on the
completion of the cross call.

This first required getting the flush_tlb_pending() call out from
switch_to() which operates with locks held and interrupts disabled.
The problem is that smp_call_function_many() cannot be invoked with
IRQs disabled and this is explicitly checked for with WARN_ON_ONCE().

We get the batch processing outside of locked IRQ disabled sections by
using some ideas from the powerpc port. Namely, we only batch inside
of arch_{enter,leave}_lazy_mmu_mode() calls.  If we're not in such a
region, we flush TLBs synchronously.

1) Get rid of xcall_flush_tlb_pending and per-cpu type
   implementations.

2) Do TLB batch cross calls instead via:

	smp_call_function_many()
		tlb_pending_func()
			__flush_tlb_pending()

3) Batch only in lazy mmu sequences:

	a) Add 'active' member to struct tlb_batch
	b) Define __HAVE_ARCH_ENTER_LAZY_MMU_MODE
	c) Set 'active' in arch_enter_lazy_mmu_mode()
	d) Run batch and clear 'active' in arch_leave_lazy_mmu_mode()
	e) Check 'active' in tlb_batch_add_one() and do a synchronous
           flush if it's clear.

4) Add infrastructure for synchronous TLB page flushes.

	a) Implement __flush_tlb_page and per-cpu variants, patch
	   as needed.
	b) Likewise for xcall_flush_tlb_page.
	c) Implement smp_flush_tlb_page() to invoke the cross-call.
	d) Wire up global_flush_tlb_page() to the right routine based
           upon CONFIG_SMP

5) It turns out that singleton batches are very common, 2 out of every
   3 batch flushes have only a single entry in them.

   The batch flush waiting is very expensive, both because of the poll
   on sibling cpu completeion, as well as because passing the tlb batch
   pointer to the sibling cpus invokes a shared memory dereference.

   Therefore, in flush_tlb_pending(), if there is only one entry in
   the batch perform a completely asynchronous global_flush_tlb_page()
   instead.

Reported-by: Dave Kleikamp 
Signed-off-by: David S. Miller 
Acked-by: Dave Kleikamp

sparc: use asm-generic version of types.h

2013-03-31T23:29:13+00:00

In sparc headers we use the following pattern:

    #if defined(__sparc__) && defined(__arch64__)

    sparc64 specific stuff

    #else

    sparc32 specific stuff

    #endif

In types.h this pattern was not followed and here
we only checked for __sparc__ for no good reason.
It was a left-over from long time ago.

I checked other architectures - and most of them
do not have any such checks. And all the recently
merged versions uses the asm-generic version.

Signed-off-by: Sam Ravnborg 
Signed-off-by: David S. Miller

sparc: use generic headers

2013-03-31T23:29:12+00:00

Use "generic-y" to add generic headers where possible

Signed-off-by: Sam Ravnborg 
Signed-off-by: David S. Miller

sparc:cleanup unused code in smp_32.h

2013-03-31T23:29:12+00:00

After genirq and generic clockevent support at sparc32,
smp4m_irq_rotate(), prof_multiplier() and prof_counter()
are no longer used and should be removed.

Find more info from commit 6baa9b20 & 62f08283.

Signed-off-by: Kefeng Wang 
Acked-by: Sam Ravnborg 
Signed-off-by: David S. Miller

sparc/iommu: fix typo s/265KB/256KB/

2013-03-31T23:29:12+00:00

IOMMU_NPTES is 64K PTEs, so the size is 256KB (= 64K * sizeof(iopte_t))

Signed-off-by: Akinobu Mita 
Cc: "David S. Miller" 
Cc: sparclinux@vger.kernel.org
Signed-off-by: David S. Miller

sparc/srmmu: clear trailing edge of bitmap properly

2013-03-31T23:29:12+00:00

srmmu_nocache_bitmap is cleared by bit_map_init().  But bit_map_init()
attempts to clear by memset(), so it can't clear the trailing edge of
bitmap properly on big-endian architecture if the number of bits is not
a multiple of BITS_PER_LONG.

Actually, the number of bits in srmmu_nocache_bitmap is not always
a multiple of BITS_PER_LONG.  It is calculated as below:

        bitmap_bits = srmmu_nocache_size >> SRMMU_NOCACHE_BITMAP_SHIFT;

srmmu_nocache_size is decided proportionally by the amount of system RAM
and it is rounded to a multiple of PAGE_SIZE.  SRMMU_NOCACHE_BITMAP_SHIFT
is defined as (PAGE_SHIFT - 4).  So it can only be said that bitmap_bits
is a multiple of 16.

This fixes the problem by using bitmap_clear() instead of memset()
in bit_map_init() and this also uses BITS_TO_LONGS() to calculate correct
size at bitmap allocation time.

Signed-off-by: Akinobu Mita 
Cc: "David S. Miller" 
Cc: sparclinux@vger.kernel.org
Signed-off-by: David S. Miller

sparc:remove unused declaration smp_boot_cpus()

2013-03-31T23:29:12+00:00

smp_boot_cpus() was replaced smp_prepare_cpus() long ago, and it no
longer needed, so delete it.

Signed-off-by: Kefeng Wang 
Acked-by: Sam Ravnborg 
Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc

2013-03-19T21:47:11+00:00

Pull sparc fixes from David Miller:
 "Just some minor fixups, a sunsu console setup panic cure, and
  recognition of a Fujitsu sun4v cpu."

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sparc: remove unused "config BITS"
  sparc: delete "if !ULTRA_HAS_POPULATION_COUNT"
  sparc64: correctly recognize SPARC64-X chips
  sparc,leon: fix GRPCI2 device0 PCI config space access
  sunsu: Fix panic in case of nonexistent port at "console=ttySY" cmdline option

sparc: remove unused "config BITS"

2013-03-19T20:23:51+00:00

sparc's asm/module.h got removed in commit
786d35d45cc40b2a51a18f73e14e135d47fdced7 ("Make most arch asm/module.h
files use asm-generic/module.h"). That removed the only two uses of this
Kconfig symbol. So we can remove its entry too.

> >From arch/sparc/Makefile:
>     ifeq ($(CONFIG_SPARC32),y)
>     [...]
>
>     [...]
>     export BITS    := 32
>     [...]
>
>     else
>     [...]
>
>     [...]
>     export BITS   := 64
>     [...]
>
> So $(BITS) is set depending on whether CONFIG_SPARC32 is set or not.
> Using $(BITS) in sparc's Makefiles is not using CONFIG_BITS. That
> doesn't count as usage of "config BITS".

Signed-off-by: Paul Bolle 
Acked-by: Sam Ravnborg 
Signed-off-by: David S. Miller