That's wired. I will have more tests on this. Thanks.
I found another bug you can try. It is also found on multiple cpus per cluster. Test step: 1. compile the driver as module. 2. hot-unplug one cpu( any one is OK) 3. insmod module 4. hot-plug the cpu ----> will cause error.
Or test step also can be: 1. hot-unplug all the cpus in one cluster 2. hot-plug the cpus in this cluster. When the second cpu gets hot-pluged, error will occur.
That's because the second cpu will call the cpufreq_add_dev_symlink() to Create the first cpu's "cpufreq link" which is already created. That needs more work to make a patch, hope you can fix it.
Thanks, Yuantian
-----Original Message----- From: cpufreq-owner@vger.kernel.org [mailto:cpufreq-owner@vger.kernel.org] On Behalf Of Viresh Kumar Sent: 2013年4月25日 15:47 To: Tang Yuantian-B29983 Cc: rjw@sisk.pl; cpufreq@vger.kernel.org; linux-pm@vger.kernel.org; Lists linaro-kernel Subject: Re: [PATCH] cpufreq: Fix the driver can not be unloaded issue
On 25 April 2013 08:16, Tang Yuantian-B29983 B29983@freescale.com wrote:
It happened when policy->cpus contains *MORE THEN ONE CPU*. Taking my board T4240 for example, it has 3 cluster, 8 CPUs for each
cluster.
The log is: # insmod ppc-corenet-cpufreq.ko ppc_corenet_cpufreq: Freescale PowerPC corenet CPU frequency scaling driver # rmmod ppc-corenet-cpufreq.ko ERROR: Module ppc_corenet_cpufreq is in use # lsmod Module Size Used by ppc_corenet_cpufreq 6542 9 # uname -a Linux T4240 3.9.0-rc1-11081-g34642bb-dirty #44 SMP Thu Apr 25 08:58:26 CST 2013 ppc64 unknown
I am not using the newest kernel (since new t4240 board has not included yet), but the issue is still there. The reason is just like what I said in patch.
I believed what you said is correct and went on testing this on my platform. 2 clusters with 2 and 3 cpus... And so i have multiple cpus per cluster or policy structure.
insmod/rmmod worked as expected without any issues.
So, for me there are no such issues. BTW, i tested this on latest rc from Linus and also on latest code from linux-next.
I am sure the counts are very well balanced and there are no issues in the latest code Atleast. -- To unsubscribe from this list: send the line "unsubscribe cpufreq" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html