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Thread-Topic: atomic_load_acq_int in ipi_nmi_handler()
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From: "Murty, Ravi" <ravi.murty@intel.com>
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Subject: atomic_load_acq_int in ipi_nmi_handler()
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Hello All,

=20

Just a quick question: Why does this function (ipi_nmi_handler) execute
a atomic_load_acq_int(&ipi_nmi_pending). Following this it calls
atomic_clear_int to clear itself out of this mask. I can't think of why
the CPU would reorder these instructions knowing there is a dependency
here.

=20

Also, since FreeBSD has masks (like ipi_nmi_pending), has there been any
work on extending this beyond 64 CPUs?

=20

Thanks

Ravi

=20