From 957efcedeef4b02f2f7e5776d64448e5c40462b4 Mon Sep 17 00:00:00 2001 From: "Shreyas B. Prabhu" Date: Fri, 8 Jul 2016 11:50:51 +0530 Subject: 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 Cc: Daniel Lezcano Cc: linux-pm@vger.kernel.org Signed-off-by: Shreyas B. Prabhu Signed-off-by: Michael Ellerman --- drivers/cpuidle/cpuidle-powernv.c | 38 ++++++++++++++++++++------------------ 1 file changed, 20 insertions(+), 18 deletions(-) (limited to 'drivers/cpuidle/cpuidle-powernv.c') diff --git a/drivers/cpuidle/cpuidle-powernv.c b/drivers/cpuidle/cpuidle-powernv.c index 3a763a823416..600bbe1a7aad 100644 --- a/drivers/cpuidle/cpuidle-powernv.c +++ b/drivers/cpuidle/cpuidle-powernv.c @@ -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; } -- cgit v1.2.1