Dear Haojian, On Tue, Apr 26, 2011 at 10:04 PM, Haojian Zhuang <haojian.zhuang@xxxxxxxxx> wrote: > > On Tue, Apr 26, 2011 at 9:55 PM, Vikram Narayanan <vikram186@xxxxxxxxx> wrote: > > Hi, > > > > I want to enable the dynamic tick aka tickless kernel feature for the > > BSP which I am developing. What are all the architecture dependent > > changes that needs to be done for implementing it. > > There was one struct by the name dyn_tick_timer, which is located > > under linux/include/asm-arm/mach/time.h file. (which is removed from v > > 2.6.27) > > Now my question is that, are all the dyn_tick_timer functionalities > > are moved to a generic interface somewhere? > CONFIG_NO_HZ is used instead. I am aware of the CONFIG_NO_HZ option. I am asking about the implementation of it. To put in a more clear way. There was a structure in the kernel source linux/include/asm-arm/mach/time.h before 2.6.27 struct dyn_tick_timer { spinlock_t lock; unsigned int state; /* Current state */ int (*enable)(void); /* Enables dynamic tick */ int (*disable)(void); /* Disables dynamic tick */ void (*reprogram)(unsigned long); /* Reprograms the timer */ int (*handler)(int, void *); }; To enable dynamic tick timer, one should implement functions for enable, disable and reprogram. But this structure is no more used in the new kernel source. In 2007 linux symposium, 3 authors talked about implementing the tickless feature using HPET timers. Now my question where does the implementation lies in the ARM architecture. Vikram > > > Are the clock source and clockevent device timers enough to take care > > of the tickless feature? > There's no relationship between NOHZ and clocksource/clockevent. > > > > - > > Vikram > > > > _______________________________________________ > > Kernelnewbies mailing list > > Kernelnewbies@xxxxxxxxxxxxxxxxx > > http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies > > _______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies