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RISC-V Linux Port
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RISC-V: Limit the scope of TLB shootdowns #107

Closed palmer-dabbelt closed 6 years ago

palmer-dabbelt commented 6 years ago

RISC-V systems perform TLB shootdows via the SBI, which currently performs an IPI to each of the remote harts which then performs a local TLB flush. This process is a bit on the slow side, but we can at least speed it up for some common cases by restricting the set of harts to shoot down to the actual set of harts that are currently participating in the given mm context, as opposed to the entire system.

This should provide a measurable performance increase, but we haven't measured it. Regardless, it seems like obviously the right thing to do :).

Signed-off-by: Andrew Waterman andrew@sifive.com Signed-off-by: Palmer Dabbelt palmer@dabbelt.com