On 11/14/2017 10:20 AM, Peter Zijlstra wrote: > On Fri, Nov 10, 2017 at 11:31:39AM -0800, Dave Hansen wrote: >> static int alloc_ds_buffer(int cpu) >> { >> + struct debug_store *ds = per_cpu_ptr(&cpu_debug_store, cpu); >> >> + memset(ds, 0, sizeof(*ds)); > Still wondering about that memset...
My guess is that it was done to mirror the zeroing done by the original kzalloc(). But, I think you're right that it's zero'd already by virtue of being static: static DEFINE_PER_CPU_SHARED_ALIGNED_USER_MAPPED(struct debug_store, cpu_debug_store); I'll queue a cleanup, or update it if I re-post the set.