I will quote the important lines of code that I think are confusing me and explain the aspects of them that I think I don't understand. init/calibrate.c
[code]loops_per_jiffy = (1 << 12); /* Initial approximation = 4096 */[/ code] The choice of number 4096 power of 2 that is 12 why is that choosen. Secondly http://lxr.linux.no/#linux+v2.6.33/init/calibrate.c#L54 In comments it is mentioning So, we do * 1. pre_start <- When we are sure that jiffy switch hasn't happened * 2. check jiffy switch * 3. start <- timer value before or after jiffy switch * 4. post_start <- When we are sure that jiffy switch has happened What is all that pre_start and why is it needed to be used over here? Here is some thing which I am wondering not because of logic in same program while (ticks == jiffies);/* Wait till the start of next jiffy */ Till the start of next jiffy what is the processor busy with or how is the delay introduced here?Not the mathematical calculation for udelay or ndelay. May be I am not clear with what I should search for.? -- You received this message because you are subscribed to the Linux Users Group. To post a message, send email to [email protected] To unsubscribe, send email to [email protected] For more options, visit our group at http://groups.google.com/group/linuxusersgroup
