On Fri, Jun 24, 2011 at 04:18:31PM +0530, Premi, Sanjeev wrote: > > -----Original Message----- > > From: Russell King - ARM Linux [mailto:linux@xxxxxxxxxxxxxxxx] > > Sent: Friday, June 24, 2011 4:14 PM > > To: Premi, Sanjeev > > Cc: linux-omap@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx > > Subject: Re: [PATCH 2/2] omap2+: pm: cpufreq: Fix > > loops_per_jiffy calculation > > > > On Fri, Jun 24, 2011 at 04:05:42PM +0530, Sanjeev Premi wrote: > > > Currently, loops_per_jiffy is being calculated before calling > > > cpufreq_notify_transition(). > > > > > > However, generic cpufreq driver adjusts the jiffies as well. > > > Double adjustment leads to incorrect value being assigned to > > > loops_per_jiffy. > > > > Are you sure the generic cpufreq driver adjusts the per-cpu > > loops_per_jiffy > > values? I don't believe it does. > > Russell, > > I am quoting the function from drivers/cpufreq/cpufreq.h > Follow the arrows: Let's go to war with quotes then, because clearly you haven't read the code properly: | #ifndef CONFIG_SMP ^^^^^^^^^^^^^^^^^^^^^ | static unsigned long l_p_j_ref; | static unsigned int l_p_j_ref_freq; | | static void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci) | { | ... code to adjust jiffies ... | } | #else | static inline void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci) | { | return; | } | #endif Notice how if CONFIG_SMP is set, adjust_jiffies becomes a no-op. So if CONFIG_SMP=y, loops_per_jiffy will _not_ be scaled by core code. -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
