1. 08 9月, 2009 1 次提交
  2. 04 9月, 2009 2 次提交
    • I
      sched: Turn on SD_BALANCE_NEWIDLE · 840a0653
      Ingo Molnar 提交于
      Start the re-tuning of the balancer by turning on newidle.
      
      It improves hackbench performance and parallelism on a 4x4 box.
      The "perf stat --repeat 10" measurements give us:
      
        domain0             domain1
        .......................................
       -SD_BALANCE_NEWIDLE -SD_BALANCE_NEWIDLE:
         2041.273208  task-clock-msecs         #      9.354 CPUs    ( +-   0.363% )
      
       +SD_BALANCE_NEWIDLE -SD_BALANCE_NEWIDLE:
         2086.326925  task-clock-msecs         #     11.934 CPUs    ( +-   0.301% )
      
       +SD_BALANCE_NEWIDLE +SD_BALANCE_NEWIDLE:
         2115.289791  task-clock-msecs         #     12.158 CPUs    ( +-   0.263% )
      Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: Andreas Herrmann <andreas.herrmann3@amd.com>
      Cc: Andreas Herrmann <andreas.herrmann3@amd.com>
      Cc: Gautham R Shenoy <ego@in.ibm.com>
      Cc: Balbir Singh <balbir@in.ibm.com>
      LKML-Reference: <new-submission>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      840a0653
    • I
      sched: Clean up topology.h · 47734f89
      Ingo Molnar 提交于
      Re-organize the flag settings so that it's visible at a glance
      which sched-domains flags are set and which not.
      
      With the new balancer code we'll need to re-tune these details
      anyway, so make it cleaner to make fewer mistakes down the
      road ;-)
      
      Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: Andreas Herrmann <andreas.herrmann3@amd.com>
      Cc: Andreas Herrmann <andreas.herrmann3@amd.com>
      Cc: Gautham R Shenoy <ego@in.ibm.com>
      Cc: Balbir Singh <balbir@in.ibm.com>
      LKML-Reference: <new-submission>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      47734f89
  3. 03 9月, 2009 10 次提交
  4. 27 8月, 2009 3 次提交
    • J
      tracing: Remove FTRACE_SYSCALL_MAX definitions · 117226d1
      Jason Baron 提交于
      Remove the FTRACE_SYSCALL_MAX definitions now that we have converted the
      syscall event tracing code to use NR_syscalls.
      Signed-off-by: NJason Baron <jbaron@redhat.com>
      Cc: Paul Mundt <lethal@linux-sh.org>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Ingo Molnar <mingo@elte.hu>
      Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
      Cc: Jiaying Zhang <jiayingz@google.com>
      Cc: Martin Bligh <mbligh@google.com>
      Cc: Li Zefan <lizf@cn.fujitsu.com>
      Cc: Josh Stone <jistone@redhat.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: H. Peter Anwin <hpa@zytor.com>
      Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      LKML-Reference: <f2240cdc8f0b1ca7617390c8f5ec90ba2bd348cf.1251146513.git.jbaron@redhat.com>
      Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
      117226d1
    • J
      tracing: Define NR_syscalls for x86_64 · a5a2f8e2
      Jason Baron 提交于
      Express the available number of syscalls in a standard way by defining
      NR_syscalls.
      
      The common way to define it is to place its definition in asm/unistd.h
      However, the number of syscalls is defined using __NR_syscall_max in
      x86-64 after building a dynamic header file "asm-offsets.h"
      
      The source file that generates this header, asm-offsets-64.c includes
      unistd.h, then if we want to express NR_syscalls from __NR_syscall_max
      in unistd.h only after generating the dynamic header file, we need a
      watchguard.
      
      If unistd.h is included from asm-offsets-64.c, then we are generating
      asm-offset.h which defines __NR_syscall_max. At this time, we don't
      want to (we can't) define NR_syscalls, then we do nothing.
      Otherwise we define NR_syscalls because we know asm-offsets.h has
      been generated.
      Signed-off-by: NJason Baron <jbaron@redhat.com>
      Acked-by: NSteven Rostedt <rostedt@goodmis.org>
      Cc: Paul Mundt <lethal@linux-sh.org>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Ingo Molnar <mingo@elte.hu>
      Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
      Cc: Jiaying Zhang <jiayingz@google.com>
      Cc: Martin Bligh <mbligh@google.com>
      Cc: Li Zefan <lizf@cn.fujitsu.com>
      Cc: Josh Stone <jistone@redhat.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: H. Peter Anwin <hpa@zytor.com>
      Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      LKML-Reference: <20090826160910.GB2658@redhat.com>
      Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
      a5a2f8e2
    • J
      tracing: Define NR_syscalls for x86 (32) · dd86dda2
      Jason Baron 提交于
      Add a NR_syscalls #define for x86. This is used in the syscall events
      tracing code. Todo: make it dynamic like x86_64.
      
      NR_syscalls is the usual name used to determine the number of syscalls
      supported by the current arch. We want to unify the use of this number
      across archs that support the syscall tracing. This also prepare to move
      some of the arch code to core code in the syscall tracing area.
      Signed-off-by: NJason Baron <jbaron@redhat.com>
      Cc: Paul Mundt <lethal@linux-sh.org>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Ingo Molnar <mingo@elte.hu>
      Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
      Cc: Jiaying Zhang <jiayingz@google.com>
      Cc: Martin Bligh <mbligh@google.com>
      Cc: Li Zefan <lizf@cn.fujitsu.com>
      Cc: Josh Stone <jistone@redhat.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: H. Peter Anwin <hpa@zytor.com>
      Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      LKML-Reference: <0f33c0f96d198fccc3ddd9ff7f5334ff5cb42706.1251146513.git.jbaron@redhat.com>
      Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
      dd86dda2
  5. 26 8月, 2009 1 次提交
    • J
      tracing: Rename FTRACE_SYSCALLS for tracepoints · 66700001
      Josh Stone 提交于
      s/HAVE_FTRACE_SYSCALLS/HAVE_SYSCALL_TRACEPOINTS/g
      s/TIF_SYSCALL_FTRACE/TIF_SYSCALL_TRACEPOINT/g
      
      The syscall enter/exit tracing is no longer specific to just ftrace, so
      they now have names that reflect their tie to tracepoints instead.
      Signed-off-by: NJosh Stone <jistone@redhat.com>
      Cc: Jason Baron <jbaron@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Ingo Molnar <mingo@elte.hu>
      Cc: Li Zefan <lizf@cn.fujitsu.com>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
      Cc: Jiaying Zhang <jiayingz@google.com>
      Cc: Martin Bligh <mbligh@google.com>
      Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
      Cc: Paul Mundt <lethal@linux-sh.org>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      LKML-Reference: <1251150194-1713-2-git-send-email-jistone@redhat.com>
      Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
      66700001
  6. 18 8月, 2009 1 次提交
    • S
      x86, pat: Allow ISA memory range uncacheable mapping requests · 1adcaafe
      Suresh Siddha 提交于
      Max Vozeler reported:
      >  Bug 13877 -  bogl-term broken with CONFIG_X86_PAT=y, works with =n
      >
      >  strace of bogl-term:
      >  814   mmap2(NULL, 65536, PROT_READ|PROT_WRITE, MAP_SHARED, 4, 0)
      >				 = -1 EAGAIN (Resource temporarily unavailable)
      >  814   write(2, "bogl: mmaping /dev/fb0: Resource temporarily unavailable\n",
      >	       57) = 57
      
      PAT code maps the ISA memory range as WB in the PAT attribute, so that
      fixed range MTRR registers define the actual memory type (UC/WC/WT etc).
      
      But the upper level is_new_memtype_allowed() API checks are failing,
      as the request here is for UC and the return tracked type is WB (Tracked type is
      WB as MTRR type for this legacy range potentially will be different for each
      4k page).
      
      Fix is_new_memtype_allowed() by always succeeding the ISA address range
      checks, as the null PAT (WB) and def MTRR fixed range register settings
      satisfy the memory type needs of the applications that map the ISA address
      range.
      Reported-and-Tested-by: NMax Vozeler <xam@debian.org>
      Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
      Signed-off-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
      Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
      1adcaafe
  7. 15 8月, 2009 1 次提交
  8. 12 8月, 2009 1 次提交
    • J
      tracing: Update FTRACE_SYSCALL_MAX · 9daa77e2
      Jason Baron 提交于
      update FTRACE_SYSCALL_MAX to the current number of syscalls
      
      FTRACE_SYSCALL_MAX is a temporary solution to get the number of
      syscalls supported by the arch until we find a more dynamic way
      to get this number.
      Signed-off-by: NJason Baron <jbaron@redhat.com>
      Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
      Cc: Jiaying Zhang <jiayingz@google.com>
      Cc: Martin Bligh <mbligh@google.com>
      Cc: Li Zefan <lizf@cn.fujitsu.com>
      Cc: Masami Hiramatsu <mhiramat@redhat.com>
      Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
      9daa77e2
  9. 09 8月, 2009 1 次提交
  10. 04 8月, 2009 4 次提交
    • J
      x86, UV: Fix macros for accessing large node numbers · 67e83f30
      Jack Steiner 提交于
      The UV chipset automatically supplies the upper bits on nodes
      being referenced by MMR accesses. These bit can be deleted from
      the hub addressing macros.
      Signed-off-by: NJack Steiner <steiner@sgi.com>
      LKML-Reference: <20090727143808.GA8076@sgi.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      67e83f30
    • J
      x86, UV: Handle missing blade-local memory correctly · 6c7184b7
      Jack Steiner 提交于
      UV blades may not have any blade-local memory. Add a field
      (nid) to the UV blade structure to indicates whether the node
      has local memory. This is needed by the GRU driver (pushed
      separately).
      Signed-off-by: NJack Steiner <steiner@sgi.com>
      Cc: linux-mm@kvack.org
      LKML-Reference: <20090727143507.GA7006@sgi.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      6c7184b7
    • H
      x86: fix assembly constraints in native_save_fl() · f1f029c7
      H. Peter Anvin 提交于
      From Gabe Black in bugzilla 13888:
      
      native_save_fl is implemented as follows:
      
        11static inline unsigned long native_save_fl(void)
        12{
        13        unsigned long flags;
        14
        15        asm volatile("# __raw_save_flags\n\t"
        16                     "pushf ; pop %0"
        17                     : "=g" (flags)
        18                     : /* no input */
        19                     : "memory");
        20
        21        return flags;
        22}
      
      If gcc chooses to put flags on the stack, for instance because this is
      inlined into a larger function with more register pressure, the offset
      of the flags variable from the stack pointer will change when the
      pushf is performed. gcc doesn't attempt to understand that fact, and
      address used for pop will still be the same. It will write to
      somewhere near flags on the stack but not actually into it and
      overwrite some other value.
      
      I saw this happen in the ide_device_add_all function when running in a
      simulator I work on. I'm assuming that some quirk of how the simulated
      hardware is set up caused the code path this is on to be executed when
      it normally wouldn't.
      
      A simple fix might be to change "=g" to "=r".
      Reported-by: NGabe Black <spamforgabe@umich.edu>
      Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
      Cc: Stable Team <stable@kernel.org>
      f1f029c7
    • P
      x86: Make 64-bit efi_ioremap use ioremap on MMIO regions · 6a7bbd57
      Paul Mackerras 提交于
      Booting current 64-bit x86 kernels on the latest Apple MacBook
      (MacBook5,2) via EFI gives the following warning:
      
      [    0.182209] ------------[ cut here ]------------
      [    0.182222] WARNING: at arch/x86/mm/pageattr.c:581 __cpa_process_fault+0x44/0xa0()
      [    0.182227] Hardware name: MacBook5,2
      [    0.182231] CPA: called for zero pte. vaddr = ffff8800ffe00000 cpa->vaddr = ffff8800ffe00000
      [    0.182236] Modules linked in:
      [    0.182242] Pid: 0, comm: swapper Not tainted 2.6.31-rc4 #6
      [    0.182246] Call Trace:
      [    0.182254]  [<ffffffff8102c754>] ? __cpa_process_fault+0x44/0xa0
      [    0.182261]  [<ffffffff81048668>] warn_slowpath_common+0x78/0xd0
      [    0.182266]  [<ffffffff81048744>] warn_slowpath_fmt+0x64/0x70
      [    0.182272]  [<ffffffff8102c7ec>] ? update_page_count+0x3c/0x50
      [    0.182280]  [<ffffffff818d25c5>] ? phys_pmd_init+0x140/0x22e
      [    0.182286]  [<ffffffff8102c754>] __cpa_process_fault+0x44/0xa0
      [    0.182292]  [<ffffffff8102ce60>] __change_page_attr_set_clr+0x5f0/0xb40
      [    0.182301]  [<ffffffff810d1035>] ? vm_unmap_aliases+0x175/0x190
      [    0.182307]  [<ffffffff8102d4ae>] change_page_attr_set_clr+0xfe/0x3d0
      [    0.182314]  [<ffffffff8102dcca>] _set_memory_uc+0x2a/0x30
      [    0.182319]  [<ffffffff8102dd4b>] set_memory_uc+0x7b/0xb0
      [    0.182327]  [<ffffffff818afe31>] efi_enter_virtual_mode+0x2ad/0x2c9
      [    0.182334]  [<ffffffff818a1c66>] start_kernel+0x2db/0x3f4
      [    0.182340]  [<ffffffff818a1289>] x86_64_start_reservations+0x99/0xb9
      [    0.182345]  [<ffffffff818a1389>] x86_64_start_kernel+0xe0/0xf2
      [    0.182357] ---[ end trace 4eaa2a86a8e2da22 ]---
      [    0.182982] init_memory_mapping: 00000000ffffc000-0000000100000000
      [    0.182993]  00ffffc000 - 0100000000 page 4k
      
      This happens because the 64-bit version of efi_ioremap calls
      init_memory_mapping for all addresses, regardless of whether they are
      RAM or MMIO.  The EFI tables on this machine ask for runtime access to
      some MMIO regions:
      
      [    0.000000] EFI: mem195: type=11, attr=0x8000000000000000, range=[0x0000000093400000-0x0000000093401000) (0MB)
      [    0.000000] EFI: mem196: type=11, attr=0x8000000000000000, range=[0x00000000ffc00000-0x00000000ffc40000) (0MB)
      [    0.000000] EFI: mem197: type=11, attr=0x8000000000000000, range=[0x00000000ffc40000-0x00000000ffc80000) (0MB)
      [    0.000000] EFI: mem198: type=11, attr=0x8000000000000000, range=[0x00000000ffc80000-0x00000000ffca4000) (0MB)
      [    0.000000] EFI: mem199: type=11, attr=0x8000000000000000, range=[0x00000000ffca4000-0x00000000ffcb4000) (0MB)
      [    0.000000] EFI: mem200: type=11, attr=0x8000000000000000, range=[0x00000000ffcb4000-0x00000000ffffc000) (3MB)
      [    0.000000] EFI: mem201: type=11, attr=0x8000000000000000, range=[0x00000000ffffc000-0x0000000100000000) (0MB)
      
      This arranges to pass the EFI memory type through to efi_ioremap, and
      makes efi_ioremap use ioremap rather than init_memory_mapping if the
      type is EFI_MEMORY_MAPPED_IO.  With this, the above warning goes away.
      Signed-off-by: NPaul Mackerras <paulus@samba.org>
      LKML-Reference: <19062.55858.533494.471153@cargo.ozlabs.ibm.com>
      Cc: Huang Ying <ying.huang@intel.com>
      Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
      6a7bbd57
  11. 03 8月, 2009 1 次提交
    • I
      debug lockups: Improve lockup detection, fix generic arch fallback · 47cab6a7
      Ingo Molnar 提交于
      As Andrew noted, my previous patch ("debug lockups: Improve lockup
      detection") broke/removed SysRq-L support from architecture that do
      not provide a __trigger_all_cpu_backtrace implementation.
      
      Restore a fallback path and clean up the SysRq-L machinery a bit:
      
       - Rename the arch method to arch_trigger_all_cpu_backtrace()
      
       - Simplify the define
      
       - Document the method a bit - in the hope of more architectures
         adding support for it.
      
      [ The patch touches Sparc code for the rename. ]
      
      Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: "David S. Miller" <davem@davemloft.net>
      LKML-Reference: <20090802140809.7ec4bb6b.akpm@linux-foundation.org>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      47cab6a7
  12. 30 7月, 2009 2 次提交
    • R
      lguest: update commentry · a91d74a3
      Rusty Russell 提交于
      Every so often, after code shuffles, I need to go through and unbitrot
      the Lguest Journey (see drivers/lguest/README).  Since we now use RCU in
      a simple form in one place I took the opportunity to expand that explanation.
      Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
      a91d74a3
    • R
      lguest: fix comment style · 2e04ef76
      Rusty Russell 提交于
      I don't really notice it (except to begrudge the extra vertical
      space), but Ingo does.  And he pointed out that one excuse of lguest
      is as a teaching tool, it should set a good example.
      Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
      Cc: Ingo Molnar <mingo@redhat.com>
      2e04ef76
  13. 28 7月, 2009 3 次提交
  14. 21 7月, 2009 2 次提交
  15. 17 7月, 2009 1 次提交
  16. 11 7月, 2009 2 次提交
  17. 10 7月, 2009 1 次提交
  18. 04 7月, 2009 2 次提交
    • E
      x86: atomic64: Inline atomic64_read() again · a79f0da8
      Eric Dumazet 提交于
      Now atomic64_read() is light weight (no register pressure and
      small icache), we can inline it again.
      
      Also use "=&A" constraint instead of "+A" to avoid warning
      about unitialized 'res' variable. (gcc had to force 0 in eax/edx)
      
        $ size vmlinux.prev vmlinux.after
           text    data     bss     dec     hex filename
        4908667  451676 1684868 7045211  6b805b vmlinux.prev
        4908651  451676 1684868 7045195  6b804b vmlinux.after
      Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: David Howells <dhowells@redhat.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Arnd Bergmann <arnd@arndb.de>
      LKML-Reference: <4A4E1AA2.30002@gmail.com>
      [ Also fix typo in atomic64_set() export ]
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      a79f0da8
    • I
      x86: atomic64: Improve atomic64_xchg() · 3a8d1788
      Ingo Molnar 提交于
      Remove the read-first logic from atomic64_xchg() and simplify
      the loop.
      
      This function was the last user of __atomic64_read() - remove it.
      
      Also, change the 'real_val' assumption from the somewhat quirky
      1ULL << 32 value to the (just as arbitrary, but simpler) value
      of 0.
      Reported-by: NLinus Torvalds <torvalds@linux-foundation.org>
      Cc: Eric Dumazet <eric.dumazet@gmail.com>
      Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: David Howells <dhowells@redhat.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Arnd Bergmann <arnd@arndb.de>
      LKML-Reference: <tip-05118ab8859492ac9ddda0154cf90e37b0a4a0b0@git.kernel.org>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      3a8d1788
  19. 03 7月, 2009 1 次提交
    • P
      x86: atomic64: Code atomic(64)_read and atomic(64)_set in C not CPP · 8e049ef0
      Paul Mackerras 提交于
      Occasionally we get bugs where atomic_read or atomic_set are
      used on atomic64_t variables or vice versa.  These bugs don't
      generate warnings on x86 because atomic_read and atomic_set are
      coded as macros rather than C functions, so we don't get any
      type-checking on their arguments; similarly for atomic64_read
      and atomic64_set in 64-bit kernels.
      
      This converts them to C functions so that the arguments are
      type-checked and bugs like this will get caught more easily. It
      also converts atomic_cmpxchg and atomic_xchg, and
      atomic64_cmpxchg and atomic64_xchg on 64-bit, so we get
      type-checking on their arguments too.
      
      Compiling a typical 64-bit x86 config, this generates no new
      warnings, and the vmlinux text is 86 bytes smaller.
      
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: David Howells <dhowells@redhat.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Arnd Bergmann <arnd@arndb.de>
      LKML-Reference: <alpine.LFD.2.01.0907021653030.3210@localhost.localdomain>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      8e049ef0