Messages in this thread | | | Date | Tue, 16 Jun 2015 12:01:19 -0700 (PDT) | From | Vikas Shivappa <> | Subject | Re: [PATCH 09/10] x86/intel_rdt: Hot cpu support for Cache Allocation |
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On Tue, 16 Jun 2015, Thomas Gleixner wrote:
> On Fri, 12 Jun 2015, Vikas Shivappa wrote: >> +static inline void intel_rdt_cpu_start(int cpu) >> +{ >> + struct intel_pqr_state *state = &per_cpu(pqr_state, cpu); >> + >> + state->closid = 0; >> + mutex_lock(&rdt_group_mutex); > > This is called from CPU_STARTING, which runs on the starting cpu with > interrupts disabled. Clearly never tested with any of the mandatory > debug configs enabled.
But this can race with cbm_update_all calling on_each_cpu_mask ? or in other words the lock helps on_each_cpu_mask not race with hot cpu code updating the rdt_cpumask since the on_each_cpu_mask is also called with the lock always.
Its tested on the 0 day build which should include the debug config. Will add a tested tag.
Thanks, Vikas
> > Thanks > > tglx >
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