linux.git/mm/memory.c, branch v2.6.17.10

[PATCH] Don't pass boot parameters to argv_init[]

2006-03-31T20:18:53+00:00

The boot cmdline is parsed in parse_early_param() and
parse_args(,unknown_bootoption).

And __setup() is used in obsolete_checksetup().

	start_kernel()
		-> parse_args()
			-> unknown_bootoption()
				-> obsolete_checksetup()

If __setup()'s callback (->setup_func()) returns 1 in
obsolete_checksetup(), obsolete_checksetup() thinks a parameter was
handled.

If ->setup_func() returns 0, obsolete_checksetup() tries other
->setup_func().  If all ->setup_func() that matched a parameter returns 0,
a parameter is seted to argv_init[].

Then, when runing /sbin/init or init=app, argv_init[] is passed to the app.
If the app doesn't ignore those arguments, it will warning and exit.

This patch fixes a wrong usage of it, however fixes obvious one only.

Signed-off-by: OGAWA Hirofumi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Merge git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial

2006-03-26T17:41:18+00:00

* git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial:
  drivers/char/ftape/lowlevel/fdc-io.c: Correct a comment
  Kconfig help: MTD_JEDECPROBE already supports Intel
  Remove ugly debugging stuff
  do_mounts.c: Minor ROOT_DEV comment cleanup
  BUG_ON() Conversion in drivers/s390/block/dasd_devmap.c
  BUG_ON() Conversion in mm/mempool.c
  BUG_ON() Conversion in mm/memory.c
  BUG_ON() Conversion in kernel/fork.c
  BUG_ON() Conversion in ipc/sem.c
  BUG_ON() Conversion in fs/ext2/
  BUG_ON() Conversion in fs/hfs/
  BUG_ON() Conversion in fs/dcache.c
  BUG_ON() Conversion in fs/buffer.c
  BUG_ON() Conversion in input/serio/hp_sdc_mlc.c
  BUG_ON() Conversion in md/dm-table.c
  BUG_ON() Conversion in md/dm-path-selector.c
  BUG_ON() Conversion in drivers/isdn
  BUG_ON() Conversion in drivers/char
  BUG_ON() Conversion in drivers/mtd/

[PATCH] Add API for flushing Anon pages

2006-03-26T16:56:53+00:00

Currently, get_user_pages() returns fully coherent pages to the kernel for
anything other than anonymous pages.  This is a problem for things like
fuse and the SCSI generic ioctl SG_IO which can potentially wish to do DMA
to anonymous pages passed in by users.

The fix is to add a new memory management API: flush_anon_page() which
is used in get_user_pages() to make anonymous pages coherent.

Signed-off-by: James Bottomley 
Cc: Russell King 
Cc: "David S. Miller" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

BUG_ON() Conversion in mm/memory.c

2006-03-26T16:30:52+00:00

this changes if() BUG(); constructs to BUG_ON() which is
cleaner, contains unlikely() and can better optimized away.

Signed-off-by: Eric Sesterhenn 
Signed-off-by: Adrian Bunk

[PATCH] mm: restore vm_normal_page check

2006-03-25T16:43:45+00:00

Hugh is rightly concerned that the CONFIG_DEBUG_VM coverage has gone too
far in vm_normal_page, considering that we expect production kernels to be
shipped with the option turned off, and that the code has been under some
large changes recently.

Signed-off-by: Nick Piggin 
Signed-off-by: Linus Torvalds

[PATCH] hugepage: Fix hugepage logic in free_pgtables() harder

2006-03-22T15:54:04+00:00

Turns out the hugepage logic in free_pgtables() was doubly broken.  The
loop coalescing multiple normal page VMAs into one call to free_pgd_range()
had an off by one error, which could mean it would coalesce one hugepage
VMA into the same bundle (checking 'vma' not 'next' in the loop).  I
transferred this bug into the new is_vm_hugetlb_page() based version.
Here's the fix.

This one didn't bite on powerpc previously for the same reason the
is_hugepage_only_range() problem didn't: powerpc's hugetlb_free_pgd_range()
is identical to free_pgd_range().  It didn't bite on ia64 because the
hugepage region is distant enough from any other region that the separated
PMD_SIZE distance test would always prevent coalescing the two together.

No libhugetlbfs testsuite regressions (ppc64, POWER5).

Signed-off-by: David Gibson 
Cc: William Lee Irwin III 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] hugepage: Fix hugepage logic in free_pgtables()

2006-03-22T15:54:03+00:00

free_pgtables() has special logic to call hugetlb_free_pgd_range() instead
of the normal free_pgd_range() on hugepage VMAs.  However, the test it uses
to do so is incorrect: it calls is_hugepage_only_range on a hugepage sized
range at the start of the vma.  is_hugepage_only_range() will return true
if the given range has any intersection with a hugepage address region, and
in this case the given region need not be hugepage aligned.  So, for
example, this test can return true if called on, say, a 4k VMA immediately
preceding a (nicely aligned) hugepage VMA.

At present we get away with this because the powerpc version of
hugetlb_free_pgd_range() is just a call to free_pgd_range().  On ia64 (the
only other arch with a non-trivial is_hugepage_only_range()) we get away
with it for a different reason; the hugepage area is not contiguous with
the rest of the user address space, and VMAs are not permitted in between,
so the test can't return a false positive there.

Nonetheless this should be fixed.  We do that in the patch below by
replacing the is_hugepage_only_range() test with an explicit test of the
VMA using is_vm_hugetlb_page().

This in turn changes behaviour for platforms where is_hugepage_only_range()
returns false always (everything except powerpc and ia64).  We address this
by ensuring that hugetlb_free_pgd_range() is defined to be identical to
free_pgd_range() (instead of a no-op) on everything except ia64.  Even so,
it will prevent some otherwise possible coalescing of calls down to
free_pgd_range().  Since this only happens for hugepage VMAs, removing this
small optimization seems unlikely to cause any trouble.

This patch causes no regressions on the libhugetlbfs testsuite - ppc64
POWER5 (8-way), ppc64 G5 (2-way) and i386 Pentium M (UP).

Signed-off-by: David Gibson 
Cc: William Lee Irwin III 
Acked-by: Hugh Dickins 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] mm: more CONFIG_DEBUG_VM

2006-03-22T15:54:02+00:00

Put a few more checks under CONFIG_DEBUG_VM

Signed-off-by: Nick Piggin 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] mm: split highorder pages

2006-03-22T15:53:57+00:00

Have an explicit mm call to split higher order pages into individual pages.
 Should help to avoid bugs and be more explicit about the code's intention.

Signed-off-by: Nick Piggin 
Cc: Russell King 
Cc: David Howells 
Cc: Ralf Baechle 
Cc: Benjamin Herrenschmidt 
Cc: Paul Mundt 
Cc: "David S. Miller" 
Cc: Chris Zankel 
Signed-off-by: Yoichi Yuasa 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] fix free swap cache latency

2006-03-17T15:51:26+00:00

Lee Revell reported 28ms latency when process with lots of swapped memory
exits.

2.6.15 introduced a latency regression when unmapping: in accounting the
zap_work latency breaker, pte_none counted 1, pte_present PAGE_SIZE, but a
swap entry counted nothing at all.  We think of pages present as the slow
case, but Lee's trace shows that free_swap_and_cache's radix tree lookup
can make a lot of work - and we could have been doing it many thousands of
times without a latency break.

Move the zap_work update up to account swap entries like pages present.
This does account non-linear pte_file entries, and unmap_mapping_range
skipping over swap entries, by the same amount even though they're quick:
but neither of those cases deserves complicating the code (and they're
treated no worse than they were in 2.6.14).

Signed-off-by: Hugh Dickins 
Acked-by: Nick Piggin 
Acked-by: Ingo Molnar 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds