Commit 251e8e3c authored May 14, 2009 by Ingo Molnar

perf_counter: Remove ACPI quirk



We had a disable/enable around acpi_idle_do_entry() due to an erratum
in an early prototype CPU i had access to. That erratum has been fixed
in the BIOS so remove the quirk.

The quirk also kept us from profiling interrupts that hit the ACPI idle
instruction - so this is an improvement as well, beyond a cleanup and
a micro-optimization.

[ Impact: improve profiling scope, cleanup, micro-optimization ]

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

parent 9029a5e3

drivers/acpi/processor_idle.c

+0 −2

Original line number	Diff line number	Diff line
		@@ -765,7 +765,6 @@ static inline void acpi_idle_do_entry(struct acpi_processor_cx *cx)
		{
		/* Don't trace irqs off for idle */
		stop_critical_timings();
		perf_disable();
		if (cx->entry_method == ACPI_CSTATE_FFH) {
		/* Call into architectural FFH based C-state */
		acpi_processor_ffh_cstate_enter(cx);
		@@ -780,7 +779,6 @@ static inline void acpi_idle_do_entry(struct acpi_processor_cx *cx)
		gets asserted in time to freeze execution properly. */
		unused = inl(acpi_gbl_FADT.xpm_timer_block.address);
		}
		perf_enable();
		start_critical_timings();
		}

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