From mboxrd@z Thu Jan 1 00:00:00 1970 From: 914059751@qq.com (=?gbk?B?uvrR7sr3?=) Date: Tue, 19 Jan 2010 15:42:53 +0800 Subject: Query about loops_per_jiffy Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi, oldhands:) I have a question about how loops_per_jiffy converted to BogoMips, loops_per_jiffy * HZ <----------- that's number of instructions CPU executes in a second BogoMips <-------------------------- Millions of instructions CPU executes in a second so , do the math! (loops_per_jiffy * HZ)/1000,000 will give a BogoMips value. then why calibrate_delay do it like the following: printk(KERN_CONT "%lu.%02lu BogoMIPS (lpj=%lu)\n", loops_per_jiffy/(500000/HZ), (loops_per_jiffy/(5000/HZ)) % 100, loops_per_jiffy); Am I missing something ? Great thanks for any tips!