1. 11 4月, 2006 1 次提交
    • B
      [PATCH] alpha: SMP boot fixes · 917b1f78
      Brian Uhrain says 提交于
      I've encountered two problems with 2.6.16 and newer kernels on my API CS20
      (dual 833MHz Alpha 21264b processors).  The first is the kernel OOPSing
      because of a NULL pointer dereference while trying to populate SysFS with the
      CPU information.  The other is that only one processor was being brought up.
      I've included a small Alpha-specific patch that fixes both problems.
      
      The first problem was caused by the CPUs never being properly registered using
      register_cpu(), the way it's done on other architectures.
      
      The second problem has to do with the removal of hwrpb_cpu_present_mask in
      arch/alpha/kernel/smp.c.  In setup_smp() in the 2.6.15 kernel sources,
      hwrpb_cpu_present_mask has a bit set for each processor that is probed, and
      afterwards cpu_present_mask is set to the cpumask for the boot CPU.  In the
      same function of the same file in the 2.6.16 sources, instead of
      hwrpb_cpu_present_mask being set, cpu_possible_map is updated for each probed
      CPU.  cpu_present_mask is still set to the cpumask of the boot CPU afterwards.
       The problem lies in include/asm-alpha/smp.h, where cpu_possible_map is
      #define'd to be cpu_present_mask.
      
      Cleanups from: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
      
       - cpu_present_mask and cpu_possible_map are essentially the same thing
         on alpha, as it doesn't support CPU hotplug;
       - allocate "struct cpu" only for present CPUs, like sparc64 does.
         Static array of "struct cpu" is just a waste of memory.
      Signed-off-by: NBrian Uhrain <buhrain@rosettastone.com>
      Cc: Richard Henderson <rth@twiddle.net>
      Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
      Cc: <stable@kernel.org>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      917b1f78
  2. 01 4月, 2006 2 次提交
  3. 29 3月, 2006 1 次提交
  4. 28 3月, 2006 2 次提交
    • A
      [PATCH] Notifier chain update: API changes · e041c683
      Alan Stern 提交于
      The kernel's implementation of notifier chains is unsafe.  There is no
      protection against entries being added to or removed from a chain while the
      chain is in use.  The issues were discussed in this thread:
      
          http://marc.theaimsgroup.com/?l=linux-kernel&m=113018709002036&w=2
      
      We noticed that notifier chains in the kernel fall into two basic usage
      classes:
      
      	"Blocking" chains are always called from a process context
      	and the callout routines are allowed to sleep;
      
      	"Atomic" chains can be called from an atomic context and
      	the callout routines are not allowed to sleep.
      
      We decided to codify this distinction and make it part of the API.  Therefore
      this set of patches introduces three new, parallel APIs: one for blocking
      notifiers, one for atomic notifiers, and one for "raw" notifiers (which is
      really just the old API under a new name).  New kinds of data structures are
      used for the heads of the chains, and new routines are defined for
      registration, unregistration, and calling a chain.  The three APIs are
      explained in include/linux/notifier.h and their implementation is in
      kernel/sys.c.
      
      With atomic and blocking chains, the implementation guarantees that the chain
      links will not be corrupted and that chain callers will not get messed up by
      entries being added or removed.  For raw chains the implementation provides no
      guarantees at all; users of this API must provide their own protections.  (The
      idea was that situations may come up where the assumptions of the atomic and
      blocking APIs are not appropriate, so it should be possible for users to
      handle these things in their own way.)
      
      There are some limitations, which should not be too hard to live with.  For
      atomic/blocking chains, registration and unregistration must always be done in
      a process context since the chain is protected by a mutex/rwsem.  Also, a
      callout routine for a non-raw chain must not try to register or unregister
      entries on its own chain.  (This did happen in a couple of places and the code
      had to be changed to avoid it.)
      
      Since atomic chains may be called from within an NMI handler, they cannot use
      spinlocks for synchronization.  Instead we use RCU.  The overhead falls almost
      entirely in the unregister routine, which is okay since unregistration is much
      less frequent that calling a chain.
      
      Here is the list of chains that we adjusted and their classifications.  None
      of them use the raw API, so for the moment it is only a placeholder.
      
        ATOMIC CHAINS
        -------------
      arch/i386/kernel/traps.c:		i386die_chain
      arch/ia64/kernel/traps.c:		ia64die_chain
      arch/powerpc/kernel/traps.c:		powerpc_die_chain
      arch/sparc64/kernel/traps.c:		sparc64die_chain
      arch/x86_64/kernel/traps.c:		die_chain
      drivers/char/ipmi/ipmi_si_intf.c:	xaction_notifier_list
      kernel/panic.c:				panic_notifier_list
      kernel/profile.c:			task_free_notifier
      net/bluetooth/hci_core.c:		hci_notifier
      net/ipv4/netfilter/ip_conntrack_core.c:	ip_conntrack_chain
      net/ipv4/netfilter/ip_conntrack_core.c:	ip_conntrack_expect_chain
      net/ipv6/addrconf.c:			inet6addr_chain
      net/netfilter/nf_conntrack_core.c:	nf_conntrack_chain
      net/netfilter/nf_conntrack_core.c:	nf_conntrack_expect_chain
      net/netlink/af_netlink.c:		netlink_chain
      
        BLOCKING CHAINS
        ---------------
      arch/powerpc/platforms/pseries/reconfig.c:	pSeries_reconfig_chain
      arch/s390/kernel/process.c:		idle_chain
      arch/x86_64/kernel/process.c		idle_notifier
      drivers/base/memory.c:			memory_chain
      drivers/cpufreq/cpufreq.c		cpufreq_policy_notifier_list
      drivers/cpufreq/cpufreq.c		cpufreq_transition_notifier_list
      drivers/macintosh/adb.c:		adb_client_list
      drivers/macintosh/via-pmu.c		sleep_notifier_list
      drivers/macintosh/via-pmu68k.c		sleep_notifier_list
      drivers/macintosh/windfarm_core.c	wf_client_list
      drivers/usb/core/notify.c		usb_notifier_list
      drivers/video/fbmem.c			fb_notifier_list
      kernel/cpu.c				cpu_chain
      kernel/module.c				module_notify_list
      kernel/profile.c			munmap_notifier
      kernel/profile.c			task_exit_notifier
      kernel/sys.c				reboot_notifier_list
      net/core/dev.c				netdev_chain
      net/decnet/dn_dev.c:			dnaddr_chain
      net/ipv4/devinet.c:			inetaddr_chain
      
      It's possible that some of these classifications are wrong.  If they are,
      please let us know or submit a patch to fix them.  Note that any chain that
      gets called very frequently should be atomic, because the rwsem read-locking
      used for blocking chains is very likely to incur cache misses on SMP systems.
      (However, if the chain's callout routines may sleep then the chain cannot be
      atomic.)
      
      The patch set was written by Alan Stern and Chandra Seetharaman, incorporating
      material written by Keith Owens and suggestions from Paul McKenney and Andrew
      Morton.
      
      [jes@sgi.com: restructure the notifier chain initialization macros]
      Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
      Signed-off-by: NChandra Seetharaman <sekharan@us.ibm.com>
      Signed-off-by: NJes Sorensen <jes@sgi.com>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      e041c683
    • D
      [PATCH] unify PFN_* macros · 22a9835c
      Dave Hansen 提交于
      Just about every architecture defines some macros to do operations on pfns.
       They're all virtually identical.  This patch consolidates all of them.
      
      One minor glitch is that at least i386 uses them in a very skeletal header
      file.  To keep away from #include dependency hell, I stuck the new
      definitions in a new, isolated header.
      
      Of all of the implementations, sh64 is the only one that varied by a bit.
      It used some masks to ensure that any sign-extension got ripped away before
      the arithmetic is done.  This has been posted to that sh64 maintainers and
      the development list.
      
      Compiles on x86, x86_64, ia64 and ppc64.
      Signed-off-by: NDave Hansen <haveblue@us.ibm.com>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      22a9835c
  5. 27 3月, 2006 3 次提交
  6. 22 3月, 2006 1 次提交
  7. 14 3月, 2006 1 次提交
  8. 10 3月, 2006 1 次提交
  9. 08 2月, 2006 1 次提交
    • I
      [PATCH] alpha: set cpu_possible_map much earlier · 328c2a8a
      Ivan Kokshaysky 提交于
      All the percpu data structure walkers want cpu_possible_map to be
      initialized early, but alpha instead populated "hwrpb_cpu_present_mask"
      early in setup_smp(), and then initialized cpu_possible_map only much
      later.
      
      Thanks go to Heiko Carstens and Dipankar Sarma for noticing.
      
      This fixes it and we can get rid of hwrpb_cpu_present_mask entirely.
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      328c2a8a
  10. 02 2月, 2006 2 次提交
  11. 19 1月, 2006 1 次提交
    • U
      [PATCH] vfs: *at functions: core · 5590ff0d
      Ulrich Drepper 提交于
      Here is a series of patches which introduce in total 13 new system calls
      which take a file descriptor/filename pair instead of a single file
      name.  These functions, openat etc, have been discussed on numerous
      occasions.  They are needed to implement race-free filesystem traversal,
      they are necessary to implement a virtual per-thread current working
      directory (think multi-threaded backup software), etc.
      
      We have in glibc today implementations of the interfaces which use the
      /proc/self/fd magic.  But this code is rather expensive.  Here are some
      results (similar to what Jim Meyering posted before).
      
      The test creates a deep directory hierarchy on a tmpfs filesystem.  Then
      rm -fr is used to remove all directories.  Without syscall support I get
      this:
      
      real    0m31.921s
      user    0m0.688s
      sys     0m31.234s
      
      With syscall support the results are much better:
      
      real    0m20.699s
      user    0m0.536s
      sys     0m20.149s
      
      The interfaces are for obvious reasons currently not much used.  But they'll
      be used.  coreutils (and Jeff's posixutils) are already using them.
      Furthermore, code like ftw/fts in libc (maybe even glob) will also start using
      them.  I expect a patch to make follow soon.  Every program which is walking
      the filesystem tree will benefit.
      Signed-off-by: NUlrich Drepper <drepper@redhat.com>
      Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
      Cc: Christoph Hellwig <hch@lst.de>
      Cc: Al Viro <viro@ftp.linux.org.uk>
      Acked-by: NIngo Molnar <mingo@elte.hu>
      Cc: Michael Kerrisk <mtk-manpages@gmx.net>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      5590ff0d
  12. 13 1月, 2006 3 次提交
  13. 12 1月, 2006 1 次提交
  14. 11 1月, 2006 1 次提交
  15. 10 1月, 2006 2 次提交
  16. 09 1月, 2006 3 次提交
    • M
      [PATCH] tiny: Make *[ug]id16 support optional · e585e470
      Matt Mackall 提交于
      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: NMatt Mackall <mpm@selenic.com>
      Signed-off-by: NAdrian Bunk <bunk@stusta.de>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      e585e470
    • E
      [PATCH] Don't attempt to power off if power off is not implemented · 5e38291d
      Eric W. Biederman 提交于
      The problem.  It is expected that /sbin/halt -p works exactly like
      /sbin/halt, when the kernel does not implement power off functionality.
      
      The kernel can do a lot of work in the reboot notifiers and in
      device_shutdown before we even get to machine_power_off.  Some of that
      shutdown is not safe if you are leaving the power on, and it definitely
      gets in the way of using sysrq or pressing ctrl-alt-del.  Since the
      shutdown happens in generic code there is no way to fix this in
      architecture specific code :(
      
      Some machines are kernel oopsing today because of this.
      
      The simple solution is to turn LINUX_REBOOT_CMD_POWER_OFF into
      LINUX_REBOOT_CMD_HALT if power_off functionality is not implemented.
      
      This has the unfortunate side effect of disabling the power off
      functionality on architectures that leave pm_power_off to null and still
      implement something in machine_power_off.  And it will break the build on
      some architectures that don't have a pm_power_off variable at all.
      
      On both counts I say tough.
      
      For architectures like alpha that don't implement the pm_power_off variable
      pm_power_off is declared in linux/pm.h and it is a generic part of our
      power management code, and all architectures should implement it.
      
      For architectures like parisc that have a default power off method in
      machine_power_off if pm_power_off is not implemented or fails.  It is easy
      enough to set the pm_power_off variable.  And nothing bad happens there,
      the machines just stop powering off.
      
      The current semantics are impossible without a flag at the top level so we
      can avoid the problem code if a power off is not implemented.  pm_power_off
      is as good a flag as any with the bonus that it works without modification
      on at least x86, x86_64, powerpc, and ppc today.
      
      Andrew can you pick this up and put this in the mm tree.  Kernels that
      don't compile or don't power off seem saner than kernels that oops or
      panic.  Until we get the arch specific patches for the problem
      architectures this probably isn't smart to push into the stable kernel.
      Unfortunately I don't have the time at the moment to walk through every
      architecture and make them work.  And even if I did I couldn't test it :(
      
      From: Hirokazu Takata <takata@linux-m32r.org>
      
          Add pm_power_off() for build fix of arch/m32r/kernel/process.c.
      
      From: Miklos Szeredi <miklos@szeredi.hu>
      
          UML build fix
      Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
      Signed-off-by: NHayato Fujiwara <fujiwara@linux-m32r.org>
      Signed-off-by: NHirokazu Takata <takata@linux-m32r.org>
      Signed-off-by: NMiklos Szeredi <miklos@szeredi.hu>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      5e38291d
    • C
      [PATCH] use ptrace_get_task_struct in various places · 6b9c7ed8
      Christoph Hellwig 提交于
      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: NChristoph Hellwig <hch@lst.de>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      6b9c7ed8
  17. 07 1月, 2006 1 次提交
  18. 16 12月, 2005 1 次提交
  19. 09 11月, 2005 1 次提交
    • N
      [PATCH] sched: resched and cpu_idle rework · 64c7c8f8
      Nick Piggin 提交于
      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: NNick Piggin <npiggin@suse.de>
      Cc: Ingo Molnar <mingo@elte.hu>
      Cc: Con Kolivas <kernel@kolivas.org>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      64c7c8f8
  20. 31 10月, 2005 1 次提交
  21. 30 10月, 2005 2 次提交
    • D
      [PATCH] memory hotplug locking: node_size_lock · 208d54e5
      Dave Hansen 提交于
      pgdat->node_size_lock is basically only neeeded in one place in the normal
      code: show_mem(), which is the arch-specific sysrq-m printing function.
      
      Strictly speaking, the architectures not doing memory hotplug do no need this
      locking in show_mem().  However, they are all included for completeness.  This
      should also make any future consolidation of all of the implementations a
      little more straightforward.
      
      This lock is also held in the sparsemem code during a memory removal, as
      sections are invalidated.  This is the place there pfn_valid() is made false
      for a memory area that's being removed.  The lock is only required when doing
      pfn_valid() operations on memory which the user does not already have a
      reference on the page, such as in show_mem().
      Signed-off-by: NDave Hansen <haveblue@us.ibm.com>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      208d54e5
    • H
      [PATCH] mm: init_mm without ptlock · 872fec16
      Hugh Dickins 提交于
      First step in pushing down the page_table_lock.  init_mm.page_table_lock has
      been used throughout the architectures (usually for ioremap): not to serialize
      kernel address space allocation (that's usually vmlist_lock), but because
      pud_alloc,pmd_alloc,pte_alloc_kernel expect caller holds it.
      
      Reverse that: don't lock or unlock init_mm.page_table_lock in any of the
      architectures; instead rely on pud_alloc,pmd_alloc,pte_alloc_kernel to take
      and drop it when allocating a new one, to check lest a racing task already
      did.  Similarly no page_table_lock in vmalloc's map_vm_area.
      
      Some temporary ugliness in __pud_alloc and __pmd_alloc: since they also handle
      user mms, which are converted only by a later patch, for now they have to lock
      differently according to whether or not it's init_mm.
      
      If sources get muddled, there's a danger that an arch source taking
      init_mm.page_table_lock will be mixed with common source also taking it (or
      neither take it).  So break the rules and make another change, which should
      break the build for such a mismatch: remove the redundant mm arg from
      pte_alloc_kernel (ppc64 scrapped its distinct ioremap_mm in 2.6.13).
      
      Exceptions: arm26 used pte_alloc_kernel on user mm, now pte_alloc_map; ia64
      used pte_alloc_map on init_mm, now pte_alloc_kernel; parisc had bad args to
      pmd_alloc and pte_alloc_kernel in unused USE_HPPA_IOREMAP code; ppc64
      map_io_page forgot to unlock on failure; ppc mmu_mapin_ram and ppc64 im_free
      took page_table_lock for no good reason.
      Signed-off-by: NHugh Dickins <hugh@veritas.com>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      872fec16
  22. 28 10月, 2005 2 次提交
  23. 03 10月, 2005 1 次提交
  24. 23 9月, 2005 1 次提交
  25. 20 9月, 2005 1 次提交
  26. 18 9月, 2005 1 次提交
  27. 11 9月, 2005 2 次提交
    • N
      [PATCH] alpha: fix-up schedule_timeout() usage · 20c6abd1
      Nishanth Aravamudan 提交于
      Use schedule_timeout_interruptible() instead of
      set_current_state()/schedule_timeout() to reduce kernel size.
      Signed-off-by: NNishanth Aravamudan <nacc@us.ibm.com>
      Cc: Richard Henderson <rth@twiddle.net>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      20c6abd1
    • I
      [PATCH] spinlock consolidation · fb1c8f93
      Ingo Molnar 提交于
      This patch (written by me and also containing many suggestions of Arjan van
      de Ven) does a major cleanup of the spinlock code.  It does the following
      things:
      
       - consolidates and enhances the spinlock/rwlock debugging code
      
       - simplifies the asm/spinlock.h files
      
       - encapsulates the raw spinlock type and moves generic spinlock
         features (such as ->break_lock) into the generic code.
      
       - cleans up the spinlock code hierarchy to get rid of the spaghetti.
      
      Most notably there's now only a single variant of the debugging code,
      located in lib/spinlock_debug.c.  (previously we had one SMP debugging
      variant per architecture, plus a separate generic one for UP builds)
      
      Also, i've enhanced the rwlock debugging facility, it will now track
      write-owners.  There is new spinlock-owner/CPU-tracking on SMP builds too.
      All locks have lockup detection now, which will work for both soft and hard
      spin/rwlock lockups.
      
      The arch-level include files now only contain the minimally necessary
      subset of the spinlock code - all the rest that can be generalized now
      lives in the generic headers:
      
       include/asm-i386/spinlock_types.h       |   16
       include/asm-x86_64/spinlock_types.h     |   16
      
      I have also split up the various spinlock variants into separate files,
      making it easier to see which does what. The new layout is:
      
         SMP                         |  UP
         ----------------------------|-----------------------------------
         asm/spinlock_types_smp.h    |  linux/spinlock_types_up.h
         linux/spinlock_types.h      |  linux/spinlock_types.h
         asm/spinlock_smp.h          |  linux/spinlock_up.h
         linux/spinlock_api_smp.h    |  linux/spinlock_api_up.h
         linux/spinlock.h            |  linux/spinlock.h
      
      /*
       * here's the role of the various spinlock/rwlock related include files:
       *
       * on SMP builds:
       *
       *  asm/spinlock_types.h: contains the raw_spinlock_t/raw_rwlock_t and the
       *                        initializers
       *
       *  linux/spinlock_types.h:
       *                        defines the generic type and initializers
       *
       *  asm/spinlock.h:       contains the __raw_spin_*()/etc. lowlevel
       *                        implementations, mostly inline assembly code
       *
       *   (also included on UP-debug builds:)
       *
       *  linux/spinlock_api_smp.h:
       *                        contains the prototypes for the _spin_*() APIs.
       *
       *  linux/spinlock.h:     builds the final spin_*() APIs.
       *
       * on UP builds:
       *
       *  linux/spinlock_type_up.h:
       *                        contains the generic, simplified UP spinlock type.
       *                        (which is an empty structure on non-debug builds)
       *
       *  linux/spinlock_types.h:
       *                        defines the generic type and initializers
       *
       *  linux/spinlock_up.h:
       *                        contains the __raw_spin_*()/etc. version of UP
       *                        builds. (which are NOPs on non-debug, non-preempt
       *                        builds)
       *
       *   (included on UP-non-debug builds:)
       *
       *  linux/spinlock_api_up.h:
       *                        builds the _spin_*() APIs.
       *
       *  linux/spinlock.h:     builds the final spin_*() APIs.
       */
      
      All SMP and UP architectures are converted by this patch.
      
      arm, i386, ia64, ppc, ppc64, s390/s390x, x64 was build-tested via
      crosscompilers.  m32r, mips, sh, sparc, have not been tested yet, but should
      be mostly fine.
      
      From: Grant Grundler <grundler@parisc-linux.org>
      
        Booted and lightly tested on a500-44 (64-bit, SMP kernel, dual CPU).
        Builds 32-bit SMP kernel (not booted or tested).  I did not try to build
        non-SMP kernels.  That should be trivial to fix up later if necessary.
      
        I converted bit ops atomic_hash lock to raw_spinlock_t.  Doing so avoids
        some ugly nesting of linux/*.h and asm/*.h files.  Those particular locks
        are well tested and contained entirely inside arch specific code.  I do NOT
        expect any new issues to arise with them.
      
       If someone does ever need to use debug/metrics with them, then they will
        need to unravel this hairball between spinlocks, atomic ops, and bit ops
        that exist only because parisc has exactly one atomic instruction: LDCW
        (load and clear word).
      
      From: "Luck, Tony" <tony.luck@intel.com>
      
         ia64 fix
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      Signed-off-by: NArjan van de Ven <arjanv@infradead.org>
      Signed-off-by: NGrant Grundler <grundler@parisc-linux.org>
      Cc: Matthew Wilcox <willy@debian.org>
      Signed-off-by: NHirokazu Takata <takata@linux-m32r.org>
      Signed-off-by: NMikael Pettersson <mikpe@csd.uu.se>
      Signed-off-by: NBenoit Boissinot <benoit.boissinot@ens-lyon.org>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      fb1c8f93