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    SubjectRe: [PATCH] 2.5.21 Nonlinear CPU support
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    On Wed, 2002-06-12 at 13:03, H. Peter Anvin wrote:

    > while ( 1 ) {
    > disable_preemption();
    > cpu = current_cpu();
    > if ( decompression_buffers[cpu] ) {
    > do_decompression(decompression_buffers[cpu]);
    > enable_preemption();
    > break; /* DONE, EXIT LOOP */
    > } else {
    > enable_preemption();
    > down_sem(allocation_semaphore);
    > /* Avoid race condition here */
    > if ( !decompression_buffers[cpu] )
    > decompression_buffers[cpu] = vmalloc(BUFFER_SIZE);
    > up_sem(allocation_semaphore);
    > }
    > }

    Just a note, in 2.5 we recently added put_cpu() and get_cpu() that work
    basically like:

    int cpu;

    cpu = get_cpu();
    /* critical non-preemptible section */
    put_cpu();

    i.e., a preempt-safe interface to smp_processor_id() that disables and
    enables preemption for you... makes it a little easier.

    Robert Love

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