On Fri, Jul 29, 2016 at 9:05 PM, Daniel. <danielhilst@xxxxxxxxx> wrote: > Nice tool @Ricardo! > > 2016-07-29 10:48 GMT-03:00 Ricardo Ribalda Delgado <ricardo.ribalda@xxxxxxxxx>: >> you can use http://lttng.org/ for analyzing this Thanks Ricardo, I will use this. >> >> Regards! >> >> On Fri, Jul 29, 2016 at 12:44 PM, Pranay Srivastava <pranjas@xxxxxxxxx> wrote: >>> On Fri, Jul 29, 2016 at 4:02 PM, Muni Sekhar <munisekharrms@xxxxxxxxx> wrote: >>>> Hi All, >>>> >>>> I have a doubt regarding the workqueue scheduling. >>>> >>>> I am using the workqueue for processing the Rx Interrupt data. I am >>>> calling schedule_work() on receiving the Rx interrupt from hardware. >>>> >>>> I calculated the time between calling the schedule_work() and >>>> workqueue task actually getting executed, Here I see many cases of >>>> less than 100 us(It is fairly good). >>>> >>>> But sometimes I see 10’s of ms and a lot in the 100’s of ms. I have >>>> seen over 0.5 secs too. I would like to know why does sometimes kernel >>>> takes longer time(in milli seconds) to schedule it? Is there any way >>>> to reduce this time gap? >>>> >>>> >>>> My code: >>>> >>>> static void my_workqueuetask(struct work_struct *work) >>>> { >>>> printk("In %s() \n",__func__); >>>> >>> You probably don't need this if it's just for your work_fn, yeah but >>> if there's race between this and something else... >>>> mutex_lock(&bh_mutex); >>>> >>>> //Do something here >>>> >>>> mutex_unlock(&bh_mutex); >>>> } >>>> >>>> >>>> static irqreturn_t my_irq_handler(int irq, void *dev) >>>> { >>>> ……; >>>> >>>> if(Rx Interrupt) >>>> schedule_work(&rx_work); >>> >>> Maybe system_wq has too much already on it's plate? >>> Have you tried the same with completion and a kthread? or >>> with your own workqueue, overkill but you can give it a shot. I have not tried this. First I will analyze with lttng and then attempts this. Does using our own workqueue reduces the latency? >>>> >>>> return IRQ_HANDLED; >>>> } >>>> >>>> -- >>>> Thanks, >>>> Sekhar >>>> >>>> _______________________________________________ >>>> Kernelnewbies mailing list >>>> Kernelnewbies@xxxxxxxxxxxxxxxxx >>>> https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies >>> >>> >>> >>> -- >>> ---P.K.S >>> >>> _______________________________________________ >>> Kernelnewbies mailing list >>> Kernelnewbies@xxxxxxxxxxxxxxxxx >>> https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies >> >> >> >> -- >> Ricardo Ribalda >> >> _______________________________________________ >> Kernelnewbies mailing list >> Kernelnewbies@xxxxxxxxxxxxxxxxx >> https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies > > > > -- > "Do or do not. There is no try" > Yoda Master > > _______________________________________________ > Kernelnewbies mailing list > Kernelnewbies@xxxxxxxxxxxxxxxxx > https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies -- Thanks, Sekhar _______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
