1. 15 Apr, 2009 1 commit
    • Linus Torvalds's avatar
      acpi-cpufreq: fix 'smp_call_function_many()' confusion · ea34f43a
      Linus Torvalds authored
      It turns out that 'smp_call_function_many()' doesn't work at all like
      'smp_call_function_single()', and my change to Andrew's patch to use it
      rather than a loop over all CPU's acpi-cpufreq doesn't work.
      
      My bad.
      
      'smp_call_function_many()' has two "features" (aka "documented bugs"):
      
       (a) it needs to be called with preemption disabled, because it uses
           smp_processor_id() without guarding the CPU lookup with 'get_cpu()'
           and 'put_cpu()' like the 'single' variant does.
      
       (b) even if the current CPU is part of the CPU mask, it won't do the
           call on that CPU.
      
      Still, we're better off trying to use 'smp_call_function_many()' than
      looping over CPU's, since it at least in theory allows us to use a
      broadcast IPI and do it all in parallel.  So let's just work around the
      silly semantic bugs in that function.
      Reported-and-tested-by: default avatarAli Gholami Rudi <ali@rudi.ir>
      Cc: Ingo Molnar <mingo@elte.hu>
      Cc: Andrew Morton <akpm@linux-foundation.org>,
      Cc: Rusty Russell <rusty@rustcorp.com.au>
      Cc: Dave Jones <davej@redhat.com>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      ea34f43a
  2. 14 Apr, 2009 27 commits
  3. 13 Apr, 2009 12 commits