From mboxrd@z Thu Jan 1 00:00:00 1970 From: hejianet@linux.vnet.ibm.com (hejianet) Date: Tue, 22 Jan 2013 17:07:37 +0800 Subject: Can jiffies freeze? In-Reply-To: References: Message-ID: <50FE56D9.5000103@linux.vnet.ibm.com> To: kernelnewbies@lists.kernelnewbies.org List-Id: kernelnewbies.lists.kernelnewbies.org how about to check the disable/enable timer interrupt? cat /proc/stat before/after 2 seconds? On 2013-01-22 13:51, sandeep kumar wrote: > Hi all > As far as I know jiffie counter is incremented HZ times/second. And it is > used to measure the time lapses in the kernel code. > > I m seeing a case where, actualy time spent in some module using giffies is > zero, but while seeing UART logs i am seein 2 sec time difference. I dont > know how to interpret this. The case which i am seeing, hrtimers are not > enabled yet, so only thing i can rely are on jiffies. > > My question here is, > Is it possible that the measured time lapse shown is "0"(jiffie count is > same before and after), but actually some time is spent?(say some 2 sec) > > In another way..can jiffies may freeze for some time? > > Please clarify... > > > > > _______________________________________________ > Kernelnewbies mailing list > Kernelnewbies at kernelnewbies.org > http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies