Re: [PATCH v3] i386: Add ratelimit for bus locks acquired in guest

[Stefan Hajnoczi]

On Mon, May 17, 2021 at 03:46:29PM -0400, Eduardo Habkost wrote:
> > +    X86MachineState *x86ms = X86_MACHINE(ms);
> > +
> > +    qemu_mutex_lock(&bus_lock_ratelimit_lock);
> > +    uint64_t delay_ns = 
> > ratelimit_calculate_delay(&x86ms->bus_lock_ratelimit_ctrl, 1);
> > +    qemu_mutex_unlock(&bus_lock_ratelimit_lock);
> 
> Stefan, ratelimit_calculate_delay() is supposed to be thread
> safe, correct?

Yes, it was a recent change by Paolo Bonzini:

  commit 4951967d84a0acbf47895add9158e2d4c6056ea0
  Author: Paolo Bonzini <pbonz...@redhat.com>
  Date:   Tue Apr 13 10:20:32 2021 +0200

      ratelimit: protect with a mutex

> 
> In that case, bus_lock_ratelimit_lock would be completely unnecessary.

I agree.

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