[RFC PATCH 2/3] powernv/cpuidle: Pass pointers instead of values to stop loop
Akshay Adiga
akshay.adiga at linux.vnet.ibm.com
Thu Aug 2 14:51:31 AEST 2018
Passing pointer to the pnv_idle_state instead of psscr value and mask.
This helps us to pass more information to the stop loop. This will help to
figure out the method to enter/exit idle state.
Signed-off-by: Akshay Adiga <akshay.adiga at linux.vnet.ibm.com>
---
arch/powerpc/include/asm/processor.h | 3 +-
arch/powerpc/platforms/powernv/idle.c | 58 ++++++++++++---------------
drivers/cpuidle/cpuidle-powernv.c | 16 +++-----
3 files changed, 32 insertions(+), 45 deletions(-)
diff --git a/arch/powerpc/include/asm/processor.h b/arch/powerpc/include/asm/processor.h
index 5debe337ea9d..34f572056add 100644
--- a/arch/powerpc/include/asm/processor.h
+++ b/arch/powerpc/include/asm/processor.h
@@ -515,8 +515,7 @@ extern unsigned long power7_idle_insn(unsigned long type); /* PNV_THREAD_NAP/etc
extern void power7_idle_type(unsigned long type);
extern unsigned long power9_idle_stop(unsigned long psscr_val);
extern unsigned long power9_offline_stop(unsigned long psscr_val);
-extern void power9_idle_type(unsigned long stop_psscr_val,
- unsigned long stop_psscr_mask);
+extern void power9_idle_type(int index);
extern void flush_instruction_cache(void);
extern void hard_reset_now(void);
diff --git a/arch/powerpc/platforms/powernv/idle.c b/arch/powerpc/platforms/powernv/idle.c
index 93accece92e3..a6ef9b68e27b 100644
--- a/arch/powerpc/platforms/powernv/idle.c
+++ b/arch/powerpc/platforms/powernv/idle.c
@@ -43,8 +43,7 @@ int nr_pnv_idle_states;
* The default stop state that will be used by ppc_md.power_save
* function on platforms that support stop instruction.
*/
-static u64 pnv_default_stop_val;
-static u64 pnv_default_stop_mask;
+struct pnv_idle_states_t *pnv_default_state;
static bool default_stop_found;
static int parse_dt_v1(struct device_node *np);
@@ -70,9 +69,7 @@ u64 pnv_first_deep_stop_state = MAX_STOP_STATE;
* psscr value and mask of the deepest stop idle state.
* Used when a cpu is offlined.
*/
-static u64 pnv_deepest_stop_psscr_val;
-static u64 pnv_deepest_stop_psscr_mask;
-static u64 pnv_deepest_stop_flag;
+static struct pnv_idle_states_t *pnv_deepest_state;
static bool deepest_stop_found;
static int pnv_save_sprs_for_deep_states(void)
@@ -92,7 +89,7 @@ static int pnv_save_sprs_for_deep_states(void)
uint64_t hid5_val = mfspr(SPRN_HID5);
uint64_t hmeer_val = mfspr(SPRN_HMEER);
uint64_t msr_val = MSR_IDLE;
- uint64_t psscr_val = pnv_deepest_stop_psscr_val;
+ uint64_t psscr_val = pnv_deepest_state->psscr_val;
for_each_present_cpu(cpu) {
uint64_t pir = get_hard_smp_processor_id(cpu);
@@ -218,18 +215,15 @@ static void pnv_alloc_idle_core_states(void)
pr_warn("cpuidle-powernv: Idle power-savings, CPU-Hotplug affected\n");
if (cpu_has_feature(CPU_FTR_ARCH_300) &&
- (pnv_deepest_stop_flag & OPAL_PM_LOSE_FULL_CONTEXT)) {
+ (pnv_deepest_state->flags & OPAL_PM_LOSE_FULL_CONTEXT)) {
/*
* Use the default stop state for CPU-Hotplug
* if available.
*/
if (default_stop_found) {
- pnv_deepest_stop_psscr_val =
- pnv_default_stop_val;
- pnv_deepest_stop_psscr_mask =
- pnv_default_stop_mask;
+ pnv_deepest_state = pnv_default_state;
pr_warn("cpuidle-powernv: Offlined CPUs will stop with psscr = 0x%016llx\n",
- pnv_deepest_stop_psscr_val);
+ pnv_deepest_state->psscr_val);
} else { /* Fallback to snooze loop for CPU-Hotplug */
deepest_stop_found = false;
pr_warn("cpuidle-powernv: Offlined CPUs will busy wait\n");
@@ -365,20 +359,20 @@ void power7_idle(void)
power7_idle_type(PNV_THREAD_NAP);
}
-static unsigned long __power9_idle_type(unsigned long stop_psscr_val,
- unsigned long stop_psscr_mask)
+static unsigned long __power9_idle_type(struct pnv_idle_states_t *state)
{
- unsigned long psscr;
+ unsigned long psscr, stop_psscr_mask, stop_psscr_val;
unsigned long srr1;
+ stop_psscr_mask = state->psscr_mask;
+ stop_psscr_val = state->psscr_val;
if (!prep_irq_for_idle_irqsoff())
return 0;
psscr = mfspr(SPRN_PSSCR);
psscr = (psscr & ~stop_psscr_mask) | stop_psscr_val;
-
__ppc64_runlatch_off();
- srr1 = power9_idle_stop(psscr);
+ srr1 = power9_idle_stop(psscr, state->opal_supported);
__ppc64_runlatch_on();
fini_irq_for_idle_irqsoff();
@@ -386,12 +380,11 @@ static unsigned long __power9_idle_type(unsigned long stop_psscr_val,
return srr1;
}
-void power9_idle_type(unsigned long stop_psscr_val,
- unsigned long stop_psscr_mask)
+void power9_idle_type(struct pnv_idle_states_t *state)
{
unsigned long srr1;
+ srr1 = __power9_idle_type(state);
- srr1 = __power9_idle_type(stop_psscr_val, stop_psscr_mask);
irq_set_pending_from_srr1(srr1);
}
@@ -400,7 +393,10 @@ void power9_idle_type(unsigned long stop_psscr_val,
*/
void power9_idle(void)
{
- power9_idle_type(pnv_default_stop_val, pnv_default_stop_mask);
+ unsigned long srr1;
+
+ srr1 = __power9_idle_type(pnv_default_state);
+ irq_set_pending_from_srr1(srr1);
}
#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
@@ -500,6 +496,7 @@ unsigned long pnv_cpu_offline(unsigned int cpu)
unsigned long srr1;
u32 idle_states = pnv_get_supported_cpuidle_states();
u64 lpcr_val;
+ struct pnv_idle_states_t *state = pnv_deepest_state;
/*
* We don't want to take decrementer interrupts while we are
@@ -520,9 +517,8 @@ unsigned long pnv_cpu_offline(unsigned int cpu)
unsigned long psscr;
psscr = mfspr(SPRN_PSSCR);
- psscr = (psscr & ~pnv_deepest_stop_psscr_mask) |
- pnv_deepest_stop_psscr_val;
- srr1 = power9_offline_stop(psscr);
+ psscr = (psscr & ~state->psscr_mask) | state->psscr_val;
+ srr1 = power9_offline_stop(psscr, state->opal_supported);
} else if ((idle_states & OPAL_PM_WINKLE_ENABLED) &&
(idle_states & OPAL_PM_LOSE_FULL_CONTEXT)) {
@@ -682,16 +678,13 @@ static int __init pnv_power9_idle_init(void)
*/
if (max_residency_ns < state->residency_ns) {
max_residency_ns = state->residency_ns;
- pnv_deepest_stop_psscr_val = state->psscr_val;
- pnv_deepest_stop_psscr_mask = state->psscr_mask;
- pnv_deepest_stop_flag = state->flags;
+ pnv_deepest_state = state;
deepest_stop_found = true;
}
if (!default_stop_found &&
(state->flags & OPAL_PM_STOP_INST_FAST)) {
- pnv_default_stop_val = state->psscr_val;
- pnv_default_stop_mask = state->psscr_mask;
+ pnv_default_state = state;
default_stop_found = true;
}
}
@@ -701,15 +694,16 @@ static int __init pnv_power9_idle_init(void)
} else {
ppc_md.power_save = power9_idle;
pr_info("cpuidle-powernv: Default stop: psscr = 0x%016llx,mask=0x%016llx\n",
- pnv_default_stop_val, pnv_default_stop_mask);
+ pnv_default_state->psscr_val,
+ pnv_default_state->psscr_mask);
}
if (unlikely(!deepest_stop_found)) {
pr_warn("cpuidle-powernv: No suitable stop state for CPU-Hotplug. Offlined CPUs will busy wait");
} else {
pr_info("cpuidle-powernv: Deepest stop: psscr = 0x%016llx,mask=0x%016llx\n",
- pnv_deepest_stop_psscr_val,
- pnv_deepest_stop_psscr_mask);
+ pnv_deepest_state->psscr_val,
+ pnv_deepest_state->psscr_mask);
}
pr_info("cpuidle-powernv: Requested Level (RL) value of first deep stop = 0x%llx\n",
diff --git a/drivers/cpuidle/cpuidle-powernv.c b/drivers/cpuidle/cpuidle-powernv.c
index f5579f0369d1..b8cb377b774b 100644
--- a/drivers/cpuidle/cpuidle-powernv.c
+++ b/drivers/cpuidle/cpuidle-powernv.c
@@ -35,13 +35,7 @@ static struct cpuidle_driver powernv_idle_driver = {
static int max_idle_state __read_mostly;
static struct cpuidle_state *cpuidle_state_table __read_mostly;
-struct stop_psscr_table {
- u64 val;
- u64 mask;
-};
-
-static struct stop_psscr_table stop_psscr_table[CPUIDLE_STATE_MAX] __read_mostly;
-
+struct pnv_idle_states_t idx_to_state_ptr[CPUIDLE_STATE_MAX] __read_mostly;
static u64 default_snooze_timeout __read_mostly;
static bool snooze_timeout_en __read_mostly;
@@ -143,8 +137,9 @@ static int stop_loop(struct cpuidle_device *dev,
struct cpuidle_driver *drv,
int index)
{
- power9_idle_type(stop_psscr_table[index].val,
- stop_psscr_table[index].mask);
+ struct pnv_idle_states_t state;
+ state = idx_to_state_ptr[index];
+ power9_idle_type(state);
return index;
}
@@ -243,8 +238,6 @@ static inline void add_powernv_state(int index, const char *name,
powernv_states[index].exit_latency = exit_latency;
powernv_states[index].enter = idle_fn;
/* For power8 and below psscr_* will be 0 */
- stop_psscr_table[index].val = psscr_val;
- stop_psscr_table[index].mask = psscr_mask;
}
/*
@@ -371,6 +364,7 @@ static int powernv_add_idle_states(void)
target_residency, exit_latency,
state->psscr_val,
state->psscr_mask);
+ idx_to_state_ptr[nr_idle_states] = state;
}
#endif
else {
--
2.18.0.rc2.85.g1fb9df7
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