On 11/27/2013 02:04 AM, Soren Brinkmann wrote:
To ensure that the timer interrupt is properly enabled/disabled across the whole CPU cluster use enable/disable_irq() instead of local_irq_disable(). Signed-off-by: Soren Brinkmann <soren.brinkmann@xxxxxxxxxx> --- drivers/clocksource/cadence_ttc_timer.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/drivers/clocksource/cadence_ttc_timer.c b/drivers/clocksource/cadence_ttc_timer.c index a92350b55d32..246d018d1e63 100644 --- a/drivers/clocksource/cadence_ttc_timer.c +++ b/drivers/clocksource/cadence_ttc_timer.c @@ -322,18 +322,16 @@ static int ttc_rate_change_clockevent_cb(struct notifier_block *nb, switch (event) { case POST_RATE_CHANGE: { - unsigned long flags; - /* * clockevents_update_freq should be called with IRQ disabled on * the CPU the timer provides events for. The timer we use is * common to both CPUs, not sure if we need to run on both * cores. */ - local_irq_save(flags); + disable_irq(ttcce->ce.irq); clockevents_update_freq(&ttcce->ce, ndata->new_rate / PRESCALE); - local_irq_restore(flags); + enable_irq(ttcce->ce.irq); /* update cached frequency */ ttc->freq = ndata->new_rate;
I am worried about the 'disable_irq' function calling 'synchronize_irq'. Isn't possible to deadlock with the ondemand cpufreq governor ? I added Viresh in Cc, he knows better than me the code path.
-- <http://www.linaro.org/> Linaro.org │ Open source software for ARM SoCs Follow Linaro: <http://www.facebook.com/pages/Linaro> Facebook | <http://twitter.com/#!/linaroorg> Twitter | <http://www.linaro.org/linaro-blog/> Blog -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html