Re: [PATCH] tracing: Allocate mask_str buffer dynamically

2017-10-25 Thread Du, Changbin
On Wed, Oct 25, 2017 at 07:24:36PM +0800, changbin...@intel.com wrote: > From: Changbin Du > > The default NR_CPUS can be very large, but actual possible nr_cpu_ids > usually is very small. For my x86 distribution, the NR_CPUS is 8192 and > nr_cpu_ids is 4. About 2 pages are wasted. > > Most mac

[PATCH] tracing: Allocate mask_str buffer dynamically

2017-10-25 Thread changbin . du
From: Changbin Du The default NR_CPUS can be very large, but actual possible nr_cpu_ids usually is very small. For my x86 distribution, the NR_CPUS is 8192 and nr_cpu_ids is 4. About 2 pages are wasted. Most machines don't have so many CPUs, so define a array with NR_CPUS just wastes memory. So