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cpuidle/powernv: cleanup cpuidle-powernv.c 

- Use stack instead of kzalloc'ed memory for variables while probing
   device tree for idle states.
 - Set cap for number of idle states that can be added to
   cpuidle_state_table
 - Minor change in way we check of_property_read_u32_array for error
   for sake of consistency
 - Drop unnecessary "&" while assigning function pointer

Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: linux-pm@vger.kernel.org
Signed-off-by: Shreyas B. Prabhu <shreyas@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Shreyas B. Prabhu 2016-07-08 11:50:51 +05:30 committed by Michael Ellerman
parent 169f3fae0c
commit 957efcedee
1 changed files with 20 additions and 18 deletions
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38
drivers/cpuidle/cpuidle-powernv.c
View File

@ -100,7 +100,7 @@ static struct cpuidle_state powernv_states[CPUIDLE_STATE_MAX] = {
.desc = "snooze",
.exit_latency = 0,
.target_residency = 0,
.enter = &snooze_loop },
.enter = snooze_loop },
};
static int powernv_cpuidle_add_cpu_notifier(struct notifier_block *n,
@ -166,7 +166,9 @@ static int powernv_add_idle_states(void)
struct device_node *power_mgt;
int nr_idle_states = 1; /* Snooze */
int dt_idle_states;
u32 *latency_ns, *residency_ns, *flags;
u32 latency_ns[CPUIDLE_STATE_MAX];
u32 residency_ns[CPUIDLE_STATE_MAX];
u32 flags[CPUIDLE_STATE_MAX];
int i, rc;
/* Currently we have snooze statically defined */
@ -184,22 +186,28 @@ static int powernv_add_idle_states(void)
goto out;
}
flags = kzalloc(sizeof(*flags) * dt_idle_states, GFP_KERNEL);
/*
* Since snooze is used as first idle state, max idle states allowed is
* CPUIDLE_STATE_MAX -1
*/
if (dt_idle_states > CPUIDLE_STATE_MAX - 1) {
pr_warn("cpuidle-powernv: discovered idle states more than allowed");
dt_idle_states = CPUIDLE_STATE_MAX - 1;
}
if (of_property_read_u32_array(power_mgt,
"ibm,cpu-idle-state-flags", flags, dt_idle_states)) {
pr_warn("cpuidle-powernv : missing ibm,cpu-idle-state-flags in DT\n");
goto out_free_flags;
goto out;
}
latency_ns = kzalloc(sizeof(*latency_ns) * dt_idle_states, GFP_KERNEL);
rc = of_property_read_u32_array(power_mgt,
"ibm,cpu-idle-state-latencies-ns", latency_ns, dt_idle_states);
if (rc) {
if (of_property_read_u32_array(power_mgt,
"ibm,cpu-idle-state-latencies-ns", latency_ns,
dt_idle_states)) {
pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-latencies-ns in DT\n");
goto out_free_latency;
goto out;
}
residency_ns = kzalloc(sizeof(*residency_ns) * dt_idle_states, GFP_KERNEL);
rc = of_property_read_u32_array(power_mgt,
"ibm,cpu-idle-state-residency-ns", residency_ns, dt_idle_states);
@ -215,7 +223,7 @@ static int powernv_add_idle_states(void)
strcpy(powernv_states[nr_idle_states].desc, "Nap");
powernv_states[nr_idle_states].flags = 0;
powernv_states[nr_idle_states].target_residency = 100;
powernv_states[nr_idle_states].enter = &nap_loop;
powernv_states[nr_idle_states].enter = nap_loop;
}
/*
@ -230,7 +238,7 @@ static int powernv_add_idle_states(void)
strcpy(powernv_states[nr_idle_states].desc, "FastSleep");
powernv_states[nr_idle_states].flags = CPUIDLE_FLAG_TIMER_STOP;
powernv_states[nr_idle_states].target_residency = 300000;
powernv_states[nr_idle_states].enter = &fastsleep_loop;
powernv_states[nr_idle_states].enter = fastsleep_loop;
}
#endif
powernv_states[nr_idle_states].exit_latency =
@ -243,12 +251,6 @@ static int powernv_add_idle_states(void)
nr_idle_states++;
}
kfree(residency_ns);
out_free_latency:
kfree(latency_ns);
out_free_flags:
kfree(flags);
out:
return nr_idle_states;
}