Commit graph

89 commits

Author SHA1 Message Date
David S. Miller
06a1be167e [SPARC]: Handle UNWIND_INFO properly.
For sparc32 we need R_SPARC_UA32 relocation support, for
sparc64 we need the handle R_SPARC_DISP32 relocations.

Based upon reports and initial patch by Martin Habets.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-05-12 12:45:50 -07:00
Martin Habets
4cfbd7eb24 [SPARC]: show device name in /proc/dvma_map
This patch will set the device name in a resource, which will be shown
in /proc/dvma_map.

Signed-off-by: Martin Habets <errandir_news@mph.eclipse.co.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-05-07 23:43:19 -07:00
Martin Habets
bb3426ad66 [SPARC]: Remove duplicate symbol exports
This patch resolves the following build warnings seen in 2.6.17-rc3:
WARNING: vmlinux: 'sys_close' exported twice. Previous export was in vmlinux
WARNING: vmlinux: 'memchr' exported twice. Previous export was in vmlinux
WARNING: vmlinux: 'strstr' exported twice. Previous export was in vmlinux
WARNING: vmlinux: 'strnlen' exported twice. Previous export was in vmlinux
WARNING: vmlinux: 'strrchr' exported twice. Previous export was in vmlinux
WARNING: vmlinux: 'strchr' exported twice. Previous export was in vmlinux
WARNING: vmlinux: 'strcmp' exported twice. Previous export was in vmlinux
WARNING: vmlinux: 'strncat' exported twice. Previous export was in vmlinux
WARNING: vmlinux: 'strcat' exported twice. Previous export was in vmlinux
WARNING: vmlinux: 'strncpy' exported twice. Previous export was in vmlinux
WARNING: vmlinux: 'strcpy' exported twice. Previous export was in vmlinux

Signed-off-by: Martin Habets <errandir_news@mph.eclipse.co.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-05-07 23:04:06 -07:00
David S. Miller
8c45112b82 [SPARC]: Hook up vmsplice into syscall tables.
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-05-03 13:55:46 -07:00
David S. Miller
5fdef39495 [SPARC]: Hook up sys_tee() into syscall tables.
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-04-14 15:29:32 -07:00
Linus Torvalds
2514395ef8 Merge git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild
* git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild:
  kconfig: fix typo in change count initialization
  kconfig: recenter menuconfig
  kconfig: revert conf behaviour change
  kconfig: fix default value for choice input
  kbuild: fix NULL dereference in scripts/mod/modpost.c
  kbuild: fix mode of checkstack.pl and other files.
  kbuild: rebuild initramfs if content of initramfs changes
  kbuild: properly pass options to hostcc when doing make O=..
  kbuild: modules_install for external modules must not remove existing modules
  kbuild: fix make dir/
  ver_linux: don't print reiser4progs version if none found
  kbuild: mips: fix sed regexp to generate asm-offset.h
  kbuild: fix building single targets with make O=.. single-target
  kbuild: use relative path to -I
  kbuild: fix unneeded rebuilds in drivers/net/chelsio after moving source tree
  kbuild: fix unneeded rebuilds in drivers/media/video after moving source tree
  kbuild: fix garbled text in modules.txt
2006-04-11 06:41:02 -07:00
Kyle McMartin
894b5779ce [PATCH] No arch-specific strpbrk implementations
While cleaning up parisc_ksyms.c earlier, I noticed that strpbrk wasn't
being exported from lib/string.c.  Investigating further, I noticed a
changeset that removed its export and added it to _ksyms.c on a few more
architectures.  The justification was that "other arches do it."

I think this is wrong, since no architecture currently defines
__HAVE_ARCH_STRPBRK, there's no reason for any of them to be exporting it
themselves.  Therefore, consolidate the export to lib/string.c.

Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-04-11 06:18:40 -07:00
KAMEZAWA Hiroyuki
fff8efe7b7 [PATCH] for_each_possible_cpu: sparc
for_each_cpu() actually iterates across all possible CPUs.  We've had mistakes
in the past where people were using for_each_cpu() where they should have been
iterating across only online or present CPUs.  This is inefficient and
possibly buggy.

We're renaming for_each_cpu() to for_each_possible_cpu() to avoid this in the
future.

This patch replaces for_each_cpu with for_each_possible_cpu.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-04-11 06:18:31 -07:00
Sam Ravnborg
b46da0567d kbuild: use relative path to -I
Using a relative path has the advantage that when the kernel source
tree is moved the relevant .o files will not be rebuild just because
the path to the kernel src has changed.
This also got rid of a user of TOPDIR - which has been deprecated for a long time now.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2006-04-04 16:56:10 +02:00
David S. Miller
289eee6fa7 [SPARC]: Wire up sys_sync_file_range() into syscall tables.
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-31 23:49:34 -08:00
David S. Miller
1339713a32 [SPARC]: Wire up sys_splice() into the syscall tables.
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-31 23:03:38 -08:00
Akinobu Mita
d59288b757 [PATCH] bitops: sparc: use generic bitops
- remove __{,test_and_}{set,clear,change}_bit() and test_bit()
- remove ffz()
- remove __ffs()
- remove sched_find_first_bit()
- remove ffs()
- remove generic_fls()
- remove generic_fls64()
- remove generic_hweight{32,16,8}()
- remove find_{next,first}{,_zero}_bit()
- remove ext2_{set,clear,test,find_first_zero,find_next_zero}_bit()
- remove ext2_{set,clear}_bit_atomic()
- remove minix_{test,set,test_and_clear,test,find_first_zero}_bit()

Signed-off-by: Akinobu Mita <mita@miraclelinux.com>
Cc: William Lee Irwin III <wli@holomorphy.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-26 08:57:14 -08:00
Bob Breuer
a54123e277 [SPARC]: Try to start getting SMP back into shape.
Todo items:
 - IRQ_INPROGRESS flag - use sparc64 irq buckets, or generic irq_desc?
 - sun4d
 - re-indent large chunks of sun4m_smp.c
 - some places assume sequential cpu numbering (i.e. 0,1 instead of 0,2)

Last I checked (with 2.6.14), random programs segfault with dual
HyperSPARC.  And with SuperSPARC II's, it seems stable but will
eventually die from a write lock error (wrong lock owner or something).

I haven't tried the HyperSPARC + highmem combination recently, so that
may still be a problem.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-23 22:36:19 -08:00
Andrew Morton
394e3902c5 [PATCH] more for_each_cpu() conversions
When we stop allocating percpu memory for not-possible CPUs we must not touch
the percpu data for not-possible CPUs at all.  The correct way of doing this
is to test cpu_possible() or to use for_each_cpu().

This patch is a kernel-wide sweep of all instances of NR_CPUS.  I found very
few instances of this bug, if any.  But the patch converts lots of open-coded
test to use the preferred helper macros.

Cc: Mikael Starvik <starvik@axis.com>
Cc: David Howells <dhowells@redhat.com>
Acked-by: Kyle McMartin <kyle@parisc-linux.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: William Lee Irwin III <wli@holomorphy.com>
Cc: Andi Kleen <ak@muc.de>
Cc: Christian Zankel <chris@zankel.net>
Cc: Philippe Elie <phil.el@wanadoo.fr>
Cc: Nathan Scott <nathans@sgi.com>
Cc: Jens Axboe <axboe@suse.de>
Cc: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-23 07:38:17 -08:00
Linus Torvalds
d04ef3a795 Merge master.kernel.org:/pub/scm/linux/kernel/git/davem/sparc-2.6
* master.kernel.org:/pub/scm/linux/kernel/git/davem/sparc-2.6:
  [SPARC64]: Add a secondary TSB for hugepage mappings.
  [SPARC]: Respect vm_page_prot in io_remap_page_range().
2006-03-22 10:56:57 -08:00
Nick Piggin
7835e98b2e [PATCH] remove set_page_count() outside mm/
set_page_count usage outside mm/ is limited to setting the refcount to 1.
Remove set_page_count from outside mm/, and replace those users with
init_page_count() and set_page_refcounted().

This allows more debug checking, and tighter control on how code is allowed
to play around with page->_count.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:02 -08:00
David S. Miller
14778d9072 [SPARC]: Respect vm_page_prot in io_remap_page_range().
Make sure the callers do a pgprot_noncached() on
vma->vm_page_prot.

Pointed out by Hugh Dickens.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-22 01:15:13 -08:00
Eric Sesterhenn
30d4d1ffed [SPARC]: BUG_ON() Conversion in arch/sparc/kernel/ioport.c
this changes if() BUG(); constructs to BUG_ON() which is
cleaner and can better optimized away

Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20 01:10:35 -08:00
David S. Miller
40ad7a6afc [SPARC]: sys_newfstatat --> sys_fstatat64
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-02-12 23:30:11 -08:00
Linus Torvalds
746f956beb Merge master.kernel.org:/pub/scm/linux/kernel/git/davem/sparc-2.6 2006-02-07 20:34:29 -08:00
David S. Miller
1b9a428901 [SPARC]: Wire up sys_unshare().
Also, the Solaris syscall table is sized differrently,
and does not go beyond entry 255, so trim off the excess
entries.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-02-07 18:11:24 -08:00
Al Viro
304cd3efe6 [PATCH] restore power-off on sparc32
Damn you, Eric

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2006-02-07 20:57:02 -05:00
David S. Miller
22f01da398 [SPARC]: Fix compile failures in math-emu.
Kill debugging default switch cases in do_one_mathemu().
That case is handled properly already and gcc hates
the empty statement that results when the debug code is
disabled.

Pointed out by kaffe.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-30 16:46:24 -08:00
David S. Miller
4415863773 [SPARC]: Increase NR_SYSCALLS to 299
To let new syscalls through.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-22 12:12:01 -08:00
David S. Miller
2d7d5f0511 [SPARC]: Add support for *at(), ppoll, and pselect syscalls.
This also includes by necessity _TIF_RESTORE_SIGMASK support,
which actually resulted in a lot of cleanups.

The sparc signal handling code is quite a mess and I should
clean it up some day.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-19 02:42:49 -08:00
Eric Sesterhenn
1ae6138834 [SPARC]: change if() BUG(); to BUG_ON in iommu.c
this patch changes if() BUG(); constructs
in iommu.c to BUG_ON(); so it gets save
to define BUG() and BUG_ON() to nullstatements.

Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-17 15:36:05 -08:00
Al Viro
36483c6b5e [PATCH] sparc: task_stack_page()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-12 09:08:53 -08:00
Al Viro
d562ef6a23 [PATCH] sparc: task_thread_info()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-12 09:08:53 -08:00
Randy Dunlap
a941564458 [PATCH] capable/capability.h (arch/)
arch: Use <linux/capability.h> where capable() is used.

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-11 18:42:14 -08:00
akpm@osdl.org
df2e71fb91 [PATCH] dump_thread() cleanup
)

From: Adrian Bunk <bunk@stusta.de>

- create one common dump_thread() prototype in kernel.h

- dump_thread() is only used in fs/binfmt_aout.c and can therefore be
  removed on all architectures where CONFIG_BINFMT_AOUT is not
  available

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-10 08:01:25 -08:00
Matt Mackall
e585e47031 [PATCH] tiny: Make *[ug]id16 support optional
Configurable 16-bit UID and friends support

This allows turning off the legacy 16 bit UID interfaces on embedded platforms.

   text    data     bss     dec     hex filename
3330172  529036  190556 4049764  3dcb64 vmlinux-baseline
3328268  529040  190556 4047864  3dc3f8 vmlinux

From: Adrian Bunk <bunk@stusta.de>

    UID16 was accidentially disabled for !EMBEDDED.

Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 20:14:11 -08:00
Christoph Hellwig
6b9c7ed848 [PATCH] use ptrace_get_task_struct in various places
The ptrace_get_task_struct() helper that I added as part of the ptrace
consolidation is useful in variety of places that currently opencode it.
Switch them to the common helpers.

Add a ptrace_traceme() helper that needs to be explicitly called, and simplify
the ptrace_get_task_struct() interface.  We don't need the request argument
now, and we return the task_struct directly, using ERR_PTR() for error
returns.  It's a bit more code in the callers, but we have two sane routines
that do one thing well now.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 20:13:51 -08:00
David S. Miller
d5784b57d2 [SPARC]: Use STABS_DEBUG and DWARF_DEBUG macros in vmlinux.lds.S
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-12-28 13:22:54 -08:00
David S. Miller
597d1f0622 [SPARC]: Kill CHILD_MAX.
It's definition is wrong (-1 means "no limit" not 999),
only the Sparc SunOS/Solaris compat code uses it, so
let's just kill it off completely from limits.h and
all referencing code.

Noticed by Ulrich Drepper.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-12-22 23:10:03 -08:00
Adrian Bunk
0b57ee9e55 [SPARC]: introduce a SPARC Kconfig symbol
Introduce a Kconfig symbol SPARC that is defined on both the sparc and
sparc64 architectures.

This symbol makes some dependencies more readable.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-12-22 23:09:54 -08:00
Al Viro
80ce8baf5d [PATCH] arch/sparc/kernel/led.c __user annotations
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-12-15 10:01:29 -08:00
Al Viro
a32972965e [PATCH] sun4c_memerr_reg __iomem annotations
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-12-15 10:01:29 -08:00
Al Viro
e4fe342f93 [PATCH] sparc: NULL noise removal (ebus.c)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-12-15 10:01:28 -08:00
Al Viro
c316ef0494 [PATCH] sparc/kernel/time: __iomem annotations
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-12-15 10:01:28 -08:00
Al Viro
f8ad23a401 [PATCH] fix iomem annotations in sparc32 pcic code
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-12-15 10:01:28 -08:00
Paul Jackson
1df2ab48f9 [SPARC]: block/ needed in final image link
With this fix, sparc links vmlinuz again using crosstool.  Without this
fix, the final link fails missing several dozen dozen symbols, beginning
with:

    kernel/built-in.o(.text+0x6fd0): In function `do_exit':
    : undefined reference to `exit_io_context'

(exit_io_context is defined in block/ll_rw_blk.c).

Signed-off-by: Paul Jackson <pj@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-12-12 14:42:44 -08:00
Paul Jackson
1d66a79dc8 [SPARC]: atomic_clear_mask build fix
This fixes one build error introduced in sparc with the patch of Oct 30,
resent Nov 4 "[patch 3/5] atomic: atomic_inc_not_zero" I still can't get
sparc to build, but at least it gets further after I remove this line. 
Apparently, this change was agreed to by Andrew and Nick on Nov 14, but
everyone thought someone else was doing it.

Signed-off-by: Paul Jackson <pj@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-12-12 14:42:31 -08:00
David S. Miller
5cd9194a1b [PATCH] sparc: convert IO remapping to VM_PFNMAP
Here are the Sparc bits.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-28 14:35:36 -08:00
Hugh Dickins
f3d48f0373 [PATCH] unpaged: fix sound Bad page states
Earlier I unifdefed PageCompound, so that snd_pcm_mmap_control_nopage and
others can give out a 0-order component of a higher-order page, which won't
be mistakenly freed when zap_pte_range unmaps it.  But many Bad page states
reported a PG_reserved was freed after all: I had missed that we need to
say __GFP_COMP to get compound page behaviour.

Some of these higher-order pages are allocated by snd_malloc_pages, some by
snd_malloc_dev_pages; or if SBUS, by sbus_alloc_consistent - but that has
no gfp arg, so add __GFP_COMP into its sparc32/64 implementations.

I'm still rather puzzled that DRM seems not to need a similar change.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-22 09:13:43 -08:00
Hugh Dickins
0b14c179a4 [PATCH] unpaged: VM_UNPAGED
Although we tend to associate VM_RESERVED with remap_pfn_range, quite a few
drivers set VM_RESERVED on areas which are then populated by nopage.  The
PageReserved removal in 2.6.15-rc1 changed VM_RESERVED not to free pages in
zap_pte_range, without changing those drivers not to set it: so their pages
just leak away.

Let's not change miscellaneous drivers now: introduce VM_UNPAGED at the core,
to flag the special areas where the ptes may have no struct page, or if they
have then it's not to be touched.  Replace most instances of VM_RESERVED in
core mm by VM_UNPAGED.  Force it on in remap_pfn_range, and the sparc and
sparc64 io_remap_pfn_range.

Revert addition of VM_RESERVED to powerpc vdso, it's not needed there.  Is it
needed anywhere?  It still governs the mm->reserved_vm statistic, and special
vmas not to be merged, and areas not to be core dumped; but could probably be
eliminated later (the drivers are probably specifying it because in 2.4 it
kept swapout off the vma, but in 2.6 we work from the LRU, which these pages
don't get on).

Use the VM_SHM slot for VM_UNPAGED, and define VM_SHM to 0: it serves no
purpose whatsoever, and should be removed from drivers when we clean up.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Acked-by: William Irwin <wli@holomorphy.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-22 09:13:42 -08:00
Nick Piggin
8426e1f6af [PATCH] atomic: inc_not_zero
Introduce an atomic_inc_not_zero operation.  Make this a special case of
atomic_add_unless because lockless pagecache actually wants
atomic_inc_not_negativeone due to its offset refcount.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: "Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-13 18:14:16 -08:00
Nick Piggin
4a6dae6d38 [PATCH] atomic: cmpxchg
Introduce an atomic_cmpxchg operation.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: "Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-13 18:14:16 -08:00
Al Viro
f037360f2e [PATCH] m68k: thread_info header cleanup
a) in smp_lock.h #include of sched.h and spinlock.h moved under #ifdef
   CONFIG_LOCK_KERNEL.

b) interrupt.h now explicitly pulls sched.h (not via smp_lock.h from
   hardirq.h as it used to)

c) in three more places we need changes to compensate for (a) - one place
   in arch/sparc needs string.h now, hardirq.h needs forward declaration of
   task_struct and preempt.h needs direct include of thread_info.h.

d) thread_info-related helpers in sched.h and thread_info.h put under
   ifndef __HAVE_THREAD_FUNCTIONS.  Obviously safe.

Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-13 18:14:13 -08:00
Tobias Klauser
940fdc6e12 [SPARC]: Use ARRAY_SIZE macro
Use ARRAY_SIZE macro instead of sizeof(x)/sizeof(x[0]) and remove a
duplicate of ARRAY_SIZE which is never used anyways.

Signed-off-by: Tobias Klauser <tklauser@nuerscht.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-11-09 12:03:05 -08:00
Nick Piggin
64c7c8f885 [PATCH] sched: resched and cpu_idle rework
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: Nick Piggin <npiggin@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Con Kolivas <kernel@kolivas.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-09 07:56:33 -08:00