On 24 July 2013 14:16, Chanwoo Choi <[email protected]> wrote: > In case that all CPUs share same cpufreq policy. Each debugfs dentry of > CPU[1-3] > except for CPU0 has symbolic link to CPU0's debugfs directory as following. > > -sh-4.1# ls -al /sys/kernel/debug/cpufreq/ > total 0 > drwxr-xr-x 3 root root 0 Jan 1 09:00 . > drwx------ 28 root root 0 Jan 1 09:00 .. > drwxr-xr-x 2 root root 0 Jan 1 09:00 cpu0 (policy->cpu is 0) > lrwxrwxrwx 1 root root 0 Jan 1 09:00 cpu1 -> ./cpu0 > lrwxrwxrwx 1 root root 0 Jan 1 09:00 cpu2 -> ./cpu0 > lrwxrwxrwx 1 root root 0 Jan 1 09:00 cpu3 -> ./cpu0 > > If turn off CPU0 state, I have to move debugfs directory data from cpu0 to > cpu1 > and again create link to cpu1's debugfs directory for CPU[2-3] debugfs > directory. > So, I removed dentry link of CPU[1-3] before creating link again. > > cpu1 > cpu2 -> ./cpu1 > cpu3 -> ./cpu1 > > But I can rewrite new link of CPU[2-3] to previous dentry > link(policy->cpu_debugfs[2] or policy->cpu_debugfs[3]) > for reducing unnecessary code without revmoval sequence.
Because we aren't freeing the debugfs node at all (just renaming it), the links might still be good after renaming.. But please check if it is true. So, according to me you need to do this: - Remove symlink for new policy->cpu, i..e cpu1 in your example - rename debugfs entry to give it to cpu1 instead of cpu0. - Set cpu0 pointer to NULL. Probably that's it. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
