Commit 19ee5e8d authored by Michał Winiarski's avatar Michał Winiarski Committed by Jani Nikula
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drm/i915/pmu: Avoid using globals for CPU hotplug state 



Attempting to bind / unbind module from devices where we have both
integrated and discreete GPU handled by i915 can lead to leaks and
warnings from cpuhp:
Error: Removing state XXX which has instances left.

Let's move the state to i915_pmu.

Fixes: 05488673 ("drm/i915/pmu: Support multiple GPUs")
Signed-off-by: default avatarMichał Winiarski <michal.winiarski@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: default avatarChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: default avatarChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200219161822.24592-1-michal.winiarski@intel.com


(cherry picked from commit f5a179d4)
Signed-off-by: default avatarJani Nikula <jani.nikula@intel.com>
parent eee18939

drivers/gpu/drm/i915/i915_pmu.c

+9 −9
Original line number Diff line number Diff line
@@ -1042,7 +1042,7 @@ static void free_event_attributes(struct i915_pmu *pmu) 


static int i915_pmu_cpu_online(unsigned int cpu, struct hlist_node *node)

{

	struct i915_pmu *pmu = hlist_entry_safe(node, typeof(*pmu), node);

	struct i915_pmu *pmu = hlist_entry_safe(node, typeof(*pmu), cpuhp.node);



	GEM_BUG_ON(!pmu->base.event_init);
@@ -1055,7 +1055,7 @@ static int i915_pmu_cpu_online(unsigned int cpu, struct hlist_node *node) 


static int i915_pmu_cpu_offline(unsigned int cpu, struct hlist_node *node)

{

	struct i915_pmu *pmu = hlist_entry_safe(node, typeof(*pmu), node);

	struct i915_pmu *pmu = hlist_entry_safe(node, typeof(*pmu), cpuhp.node);

	unsigned int target;



	GEM_BUG_ON(!pmu->base.event_init);
@@ -1072,8 +1072,6 @@ static int i915_pmu_cpu_offline(unsigned int cpu, struct hlist_node *node) 
	return 0;

}



static enum cpuhp_state cpuhp_slot = CPUHP_INVALID;



static int i915_pmu_register_cpuhp_state(struct i915_pmu *pmu)

{

	enum cpuhp_state slot;
@@ -1087,21 +1085,22 @@ static int i915_pmu_register_cpuhp_state(struct i915_pmu *pmu) 
		return ret;



	slot = ret;

	ret = cpuhp_state_add_instance(slot, &pmu->node);

	ret = cpuhp_state_add_instance(slot, &pmu->cpuhp.node);

	if (ret) {

		cpuhp_remove_multi_state(slot);

		return ret;

	}



	cpuhp_slot = slot;

	pmu->cpuhp.slot = slot;

	return 0;

}



static void i915_pmu_unregister_cpuhp_state(struct i915_pmu *pmu)

{

	WARN_ON(cpuhp_slot == CPUHP_INVALID);

	WARN_ON(cpuhp_state_remove_instance(cpuhp_slot, &pmu->node));

	cpuhp_remove_multi_state(cpuhp_slot);

	WARN_ON(pmu->cpuhp.slot == CPUHP_INVALID);

	WARN_ON(cpuhp_state_remove_instance(pmu->cpuhp.slot, &pmu->cpuhp.node));

	cpuhp_remove_multi_state(pmu->cpuhp.slot);

	pmu->cpuhp.slot = CPUHP_INVALID;

}



static bool is_igp(struct drm_i915_private *i915)
@@ -1128,6 +1127,7 @@ void i915_pmu_register(struct drm_i915_private *i915) 
	spin_lock_init(&pmu->lock);

	hrtimer_init(&pmu->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);

	pmu->timer.function = i915_sample;

	pmu->cpuhp.slot = CPUHP_INVALID;



	if (!is_igp(i915)) {

		pmu->name = kasprintf(GFP_KERNEL,

drivers/gpu/drm/i915/i915_pmu.h

+5 −2
Original line number Diff line number Diff line
@@ -39,9 +39,12 @@ struct i915_pmu_sample { 


struct i915_pmu {

	/**

	 * @node: List node for CPU hotplug handling.

	 * @cpuhp: Struct used for CPU hotplug handling.

	 */

	struct {

		struct hlist_node node;

		enum cpuhp_state slot;

	} cpuhp;

	/**

	 * @base: PMU base.

	 */

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