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    Subject[patch 5/6] cleanups to help using per-cpu variables from asm
    This patch does a few small cleanups:
    - use PER_CPU_NAME to generate the names of per-cpu variables
    - use lea to add the per_cpu offset in PER_CPU(), because it doesn't
    affect condition flags
    - add PER_CPU_VAR which allows direct access to pre-cpu variables
    with the %fs: prefix on SMP.

    Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
    Cc: Rusty Russell <rusty@rustcorp.com.au>
    Cc: Andi Kleen <ak@suse.de>

    ---
    include/asm-i386/percpu.h | 12 +++++++-----
    1 file changed, 7 insertions(+), 5 deletions(-)

    ===================================================================
    --- a/include/asm-i386/percpu.h
    +++ b/include/asm-i386/percpu.h
    @@ -16,12 +16,14 @@
    * PER_CPU(cpu_gdt_descr, %ebx)
    */
    #ifdef CONFIG_SMP
    +#define PER_CPU(var, reg) \
    + movl %fs:per_cpu__##this_cpu_off, reg; \
    + lea per_cpu__##var(reg), reg
    +#define PER_CPU_VAR(var) %fs:per_cpu__##var
    +#else /* ! SMP */
    #define PER_CPU(var, reg) \
    - movl %fs:per_cpu__this_cpu_off, reg; \
    - addl $per_cpu__##var, reg
    -#else /* ! SMP */
    -#define PER_CPU(var, reg) \
    - movl $per_cpu__##var, reg;
    + movl $per_cpu__##var, reg
    +#define PER_CPU_VAR(var) per_cpu__##var
    #endif /* SMP */

    #else /* ...!ASSEMBLY */
    --

    -
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