Commit-ID: d8c6ad3184ca6516a5cf457af1afaa293d8f09c0 Gitweb: http://git.kernel.org/tip/d8c6ad3184ca6516a5cf457af1afaa293d8f09c0 Author: Nicolas Pitre <nicolas.pi...@linaro.org> AuthorDate: Wed, 29 Jan 2014 12:45:10 -0500 Committer: Ingo Molnar <mi...@kernel.org> CommitDate: Tue, 11 Feb 2014 09:58:24 +0100
sched/idle, PPC: Remove redundant cpuidle_idle_call() The core idle loop now takes care of it. However a few things need checking: - Invocation of cpuidle_idle_call() in pseries_lpar_idle() happened through arch_cpu_idle() and was therefore always preceded by a call to ppc64_runlatch_off(). To preserve this property now that cpuidle_idle_call() is invoked directly from core code, a call to ppc64_runlatch_off() has been added to idle_loop_prolog() in platforms/pseries/processor_idle.c. - Similarly, cpuidle_idle_call() was followed by ppc64_runlatch_off() so a call to the later has been added to idle_loop_epilog(). - And since arch_cpu_idle() always made sure to re-enable IRQs if they were not enabled, this is now done in idle_loop_epilog() as well. The above was made in order to keep the execution flow close to the original. I don't know if that was strictly necessary. Someone well aquainted with the platform details might find some room for possible optimizations. Signed-off-by: Nicolas Pitre <n...@linaro.org> Reviewed-by: Preeti U Murthy <pre...@linux.vnet.ibm.com> Cc: "Rafael J. Wysocki" <r...@rjwysocki.net> Cc: Daniel Lezcano <daniel.lezc...@linaro.org> Cc: linux-arm-ker...@lists.infradead.org Cc: linuxppc-...@lists.ozlabs.org Cc: linux...@vger.kernel.org Cc: linux...@vger.kernel.org Cc: Russell King <li...@arm.linux.org.uk> Cc: linaro-ker...@lists.linaro.org Cc: Benjamin Herrenschmidt <b...@kernel.crashing.org> Cc: Paul Mundt <let...@linux-sh.org> Signed-off-by: Peter Zijlstra <pet...@infradead.org> Link: http://lkml.kernel.org/n/tip-47o4m03citrfg9y1vxic5...@git.kernel.org Signed-off-by: Ingo Molnar <mi...@kernel.org> --- arch/powerpc/platforms/pseries/setup.c | 34 ++++++++++++++-------------------- drivers/cpuidle/cpuidle-pseries.c | 5 +++++ 2 files changed, 19 insertions(+), 20 deletions(-) diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c index 8e639d7..c737d55 100644 --- a/arch/powerpc/platforms/pseries/setup.c +++ b/arch/powerpc/platforms/pseries/setup.c @@ -39,7 +39,6 @@ #include <linux/irq.h> #include <linux/seq_file.h> #include <linux/root_dev.h> -#include <linux/cpuidle.h> #include <linux/of.h> #include <linux/kexec.h> @@ -356,29 +355,24 @@ early_initcall(alloc_dispatch_log_kmem_cache); static void pseries_lpar_idle(void) { - /* This would call on the cpuidle framework, and the back-end pseries - * driver to go to idle states + /* + * Default handler to go into low thread priority and possibly + * low power mode by cedeing processor to hypervisor */ - if (cpuidle_idle_call()) { - /* On error, execute default handler - * to go into low thread priority and possibly - * low power mode by cedeing processor to hypervisor - */ - /* Indicate to hypervisor that we are idle. */ - get_lppaca()->idle = 1; + /* Indicate to hypervisor that we are idle. */ + get_lppaca()->idle = 1; - /* - * Yield the processor to the hypervisor. We return if - * an external interrupt occurs (which are driven prior - * to returning here) or if a prod occurs from another - * processor. When returning here, external interrupts - * are enabled. - */ - cede_processor(); + /* + * Yield the processor to the hypervisor. We return if + * an external interrupt occurs (which are driven prior + * to returning here) or if a prod occurs from another + * processor. When returning here, external interrupts + * are enabled. + */ + cede_processor(); - get_lppaca()->idle = 0; - } + get_lppaca()->idle = 0; } /* diff --git a/drivers/cpuidle/cpuidle-pseries.c b/drivers/cpuidle/cpuidle-pseries.c index 7ab564a..d486489 100644 --- a/drivers/cpuidle/cpuidle-pseries.c +++ b/drivers/cpuidle/cpuidle-pseries.c @@ -29,6 +29,7 @@ static struct cpuidle_state *cpuidle_state_table; static inline void idle_loop_prolog(unsigned long *in_purr) { + ppc64_runlatch_off(); *in_purr = mfspr(SPRN_PURR); /* * Indicate to the HV that we are idle. Now would be @@ -45,6 +46,10 @@ static inline void idle_loop_epilog(unsigned long in_purr) wait_cycles += mfspr(SPRN_PURR) - in_purr; get_lppaca()->wait_state_cycles = cpu_to_be64(wait_cycles); get_lppaca()->idle = 0; + + if (irqs_disabled()) + local_irq_enable(); + ppc64_runlatch_on(); } static int snooze_loop(struct cpuidle_device *dev, -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
