on 02/10/2012 20:18 Sean Bruno said the following: > >> The following patch adds only per-CPU notifications. >> >> acpi_cpu: explicitly notify userland about c-state changes >> >> diff --git a/sys/dev/acpica/acpi_cpu.c b/sys/dev/acpica/acpi_cpu.c >> index 82e204a..15201f9 100644 >> --- a/sys/dev/acpica/acpi_cpu.c >> +++ b/sys/dev/acpica/acpi_cpu.c >> @@ -1054,6 +1054,8 @@ acpi_cpu_notify(ACPI_HANDLE h, UINT32 notify, void >> *context) >> ACPI_SERIAL_BEGIN(cpu); >> acpi_cpu_set_cx_lowest(sc); >> ACPI_SERIAL_END(cpu); >> + >> + acpi_UserNotify("PROCESSOR", sc->cpu_handle, notify); >> } >> >> static int >> > > So quick question, does this happen a lot on a system with a sporadic > workload? Does this introduce overhead to the system to service the > notification requests?
I am not sure who can answer this question. It is up to ACPI platform to decide when it changes _available C-states_. OS doesn't have control over that. P.S. I hope you haven't confused this notification for a notification about _current_ C-state changing. -- Andriy Gapon _______________________________________________ freebsd-acpi@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-acpi To unsubscribe, send any mail to "freebsd-acpi-unsubscr...@freebsd.org"