Avi Kivity wrote:
Anthony Liguori wrote:+/* + * Control register reads can be trapped. Since trapping is relatively + * expensive, we can avoid paying the cost by caching logically. + */ +static unsigned long kvm_read_cr(int reg) +{ + struct kvm_paravirt_state *state + = per_cpu(paravirt_state, smp_processor_id()); + + if (unlikely(!state->cr_valid[reg])) { + if (reg == 0) + state->cached_cr[reg] = native_read_cr0(); + else if (reg == 3) + state->cached_cr[reg] = native_read_cr3(); + else if (reg == 4) + state->cached_cr[reg] = native_read_cr4(); + else + BUG(); + state->cr_valid[reg] = 1; + } + return state->cached_cr[reg]; +} +It would be good to declare this (and kvm_write_cr) always_inline. These functions are never called with a non-constant reg parameters, and the unsightly if tree (more readable as a switch, IMO) will fold nicely when inlined.
Ok. Regards, Anthony Liguori _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/virtualization
