[PATCH] ppc64: Move pSeries idle functions into pSeries_setup.c
dedicated_idle() and shared_idle() are only used by pSeries, so move them into
pSeries_setup.c
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/ppc64/kernel/pSeries_setup.c b/arch/ppc64/kernel/pSeries_setup.c
index 44d9af7..849ed9b 100644
--- a/arch/ppc64/kernel/pSeries_setup.c
+++ b/arch/ppc64/kernel/pSeries_setup.c
@@ -418,6 +418,133 @@
return 1;
}
+DECLARE_PER_CPU(unsigned long, smt_snooze_delay);
+
+int dedicated_idle(void)
+{
+ long oldval;
+ struct paca_struct *lpaca = get_paca(), *ppaca;
+ unsigned long start_snooze;
+ unsigned long *smt_snooze_delay = &__get_cpu_var(smt_snooze_delay);
+ unsigned int cpu = smp_processor_id();
+
+ ppaca = &paca[cpu ^ 1];
+
+ while (1) {
+ /*
+ * Indicate to the HV that we are idle. Now would be
+ * a good time to find other work to dispatch.
+ */
+ lpaca->lppaca.idle = 1;
+
+ oldval = test_and_clear_thread_flag(TIF_NEED_RESCHED);
+ if (!oldval) {
+ set_thread_flag(TIF_POLLING_NRFLAG);
+ start_snooze = __get_tb() +
+ *smt_snooze_delay * tb_ticks_per_usec;
+ while (!need_resched() && !cpu_is_offline(cpu)) {
+ /*
+ * Go into low thread priority and possibly
+ * low power mode.
+ */
+ HMT_low();
+ HMT_very_low();
+
+ if (*smt_snooze_delay == 0 ||
+ __get_tb() < start_snooze)
+ continue;
+
+ HMT_medium();
+
+ if (!(ppaca->lppaca.idle)) {
+ local_irq_disable();
+
+ /*
+ * We are about to sleep the thread
+ * and so wont be polling any
+ * more.
+ */
+ clear_thread_flag(TIF_POLLING_NRFLAG);
+
+ /*
+ * SMT dynamic mode. Cede will result
+ * in this thread going dormant, if the
+ * partner thread is still doing work.
+ * Thread wakes up if partner goes idle,
+ * an interrupt is presented, or a prod
+ * occurs. Returning from the cede
+ * enables external interrupts.
+ */
+ if (!need_resched())
+ cede_processor();
+ else
+ local_irq_enable();
+ } else {
+ /*
+ * Give the HV an opportunity at the
+ * processor, since we are not doing
+ * any work.
+ */
+ poll_pending();
+ }
+ }
+
+ clear_thread_flag(TIF_POLLING_NRFLAG);
+ } else {
+ set_need_resched();
+ }
+
+ HMT_medium();
+ lpaca->lppaca.idle = 0;
+ schedule();
+ if (cpu_is_offline(cpu) && system_state == SYSTEM_RUNNING)
+ cpu_die();
+ }
+ return 0;
+}
+
+static int shared_idle(void)
+{
+ struct paca_struct *lpaca = get_paca();
+ unsigned int cpu = smp_processor_id();
+
+ while (1) {
+ /*
+ * Indicate to the HV that we are idle. Now would be
+ * a good time to find other work to dispatch.
+ */
+ lpaca->lppaca.idle = 1;
+
+ while (!need_resched() && !cpu_is_offline(cpu)) {
+ local_irq_disable();
+
+ /*
+ * 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.
+ *
+ * Check need_resched() again with interrupts disabled
+ * to avoid a race.
+ */
+ if (!need_resched())
+ cede_processor();
+ else
+ local_irq_enable();
+ }
+
+ HMT_medium();
+ lpaca->lppaca.idle = 0;
+ schedule();
+ if (cpu_is_offline(smp_processor_id()) &&
+ system_state == SYSTEM_RUNNING)
+ cpu_die();
+ }
+
+ return 0;
+}
+
struct machdep_calls __initdata pSeries_md = {
.probe = pSeries_probe,
.setup_arch = pSeries_setup_arch,