1. 29 3月, 2011 1 次提交
  2. 28 3月, 2011 1 次提交
  3. 26 2月, 2011 1 次提交
    • T
      genirq: Provide forced interrupt threading · 8d32a307
      Thomas Gleixner 提交于
      Add a commandline parameter "threadirqs" which forces all interrupts except
      those marked IRQF_NO_THREAD to run threaded. That's mostly a debug option to
      allow retrieving better debug data from crashing interrupt handlers. If
      "threadirqs" is not enabled on the kernel command line, then there is no
      impact in the interrupt hotpath.
      
      Architecture code needs to select CONFIG_IRQ_FORCED_THREADING after
      marking the interrupts which cant be threaded IRQF_NO_THREAD. All
      interrupts which have IRQF_TIMER set are implict marked
      IRQF_NO_THREAD. Also all PER_CPU interrupts are excluded.
      
      Forced threading hard interrupts also forces all soft interrupt
      handling into thread context.
      
      When enabled it might slow down things a bit, but for debugging problems in
      interrupt code it's a reasonable penalty as it does not immediately
      crash and burn the machine when an interrupt handler is buggy.
      
      Some test results on a Core2Duo machine:
      
      Cache cold run of:
       # time git grep irq_desc
      
            non-threaded       threaded
       real 1m18.741s          1m19.061s
       user 0m1.874s           0m1.757s
       sys  0m5.843s           0m5.427s
      
       # iperf -c server
      non-threaded
      [  3]  0.0-10.0 sec  1.09 GBytes   933 Mbits/sec
      [  3]  0.0-10.0 sec  1.09 GBytes   934 Mbits/sec
      [  3]  0.0-10.0 sec  1.09 GBytes   933 Mbits/sec
      threaded
      [  3]  0.0-10.0 sec  1.09 GBytes   939 Mbits/sec
      [  3]  0.0-10.0 sec  1.09 GBytes   934 Mbits/sec
      [  3]  0.0-10.0 sec  1.09 GBytes   937 Mbits/sec
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      LKML-Reference: <20110223234956.772668648@linutronix.de>
      8d32a307
  4. 19 2月, 2011 30 次提交
  5. 12 10月, 2010 4 次提交
  6. 04 10月, 2010 3 次提交