xref: /linux/drivers/gpu/drm/i915/i915_pmu.h (revision 0d3b051adbb72ed81956447d0d1e54d5943ee6f5)
1 /*
2  * SPDX-License-Identifier: MIT
3  *
4  * Copyright © 2017-2018 Intel Corporation
5  */
6 
7 #ifndef __I915_PMU_H__
8 #define __I915_PMU_H__
9 
10 #include <linux/hrtimer.h>
11 #include <linux/perf_event.h>
12 #include <linux/spinlock_types.h>
13 #include <uapi/drm/i915_drm.h>
14 
15 struct drm_i915_private;
16 
17 enum {
18 	__I915_SAMPLE_FREQ_ACT = 0,
19 	__I915_SAMPLE_FREQ_REQ,
20 	__I915_SAMPLE_RC6,
21 	__I915_SAMPLE_RC6_LAST_REPORTED,
22 	__I915_NUM_PMU_SAMPLERS
23 };
24 
25 /**
26  * How many different events we track in the global PMU mask.
27  *
28  * It is also used to know to needed number of event reference counters.
29  */
30 #define I915_PMU_MASK_BITS \
31 	((1 << I915_PMU_SAMPLE_BITS) + \
32 	 (I915_PMU_LAST + 1 - __I915_PMU_OTHER(0)))
33 
34 #define I915_ENGINE_SAMPLE_COUNT (I915_SAMPLE_SEMA + 1)
35 
36 struct i915_pmu_sample {
37 	u64 cur;
38 };
39 
40 struct i915_pmu {
41 	/**
42 	 * @cpuhp: Struct used for CPU hotplug handling.
43 	 */
44 	struct {
45 		struct hlist_node node;
46 		unsigned int cpu;
47 	} cpuhp;
48 	/**
49 	 * @base: PMU base.
50 	 */
51 	struct pmu base;
52 	/**
53 	 * @closed: i915 is unregistering.
54 	 */
55 	bool closed;
56 	/**
57 	 * @name: Name as registered with perf core.
58 	 */
59 	const char *name;
60 	/**
61 	 * @lock: Lock protecting enable mask and ref count handling.
62 	 */
63 	spinlock_t lock;
64 	/**
65 	 * @timer: Timer for internal i915 PMU sampling.
66 	 */
67 	struct hrtimer timer;
68 	/**
69 	 * @enable: Bitmask of all currently enabled events.
70 	 *
71 	 * Bits are derived from uAPI event numbers in a way that low 16 bits
72 	 * correspond to engine event _sample_ _type_ (I915_SAMPLE_QUEUED is
73 	 * bit 0), and higher bits correspond to other events (for instance
74 	 * I915_PMU_ACTUAL_FREQUENCY is bit 16 etc).
75 	 *
76 	 * In other words, low 16 bits are not per engine but per engine
77 	 * sampler type, while the upper bits are directly mapped to other
78 	 * event types.
79 	 */
80 	u64 enable;
81 
82 	/**
83 	 * @timer_last:
84 	 *
85 	 * Timestmap of the previous timer invocation.
86 	 */
87 	ktime_t timer_last;
88 
89 	/**
90 	 * @enable_count: Reference counts for the enabled events.
91 	 *
92 	 * Array indices are mapped in the same way as bits in the @enable field
93 	 * and they are used to control sampling on/off when multiple clients
94 	 * are using the PMU API.
95 	 */
96 	unsigned int enable_count[I915_PMU_MASK_BITS];
97 	/**
98 	 * @timer_enabled: Should the internal sampling timer be running.
99 	 */
100 	bool timer_enabled;
101 	/**
102 	 * @sample: Current and previous (raw) counters for sampling events.
103 	 *
104 	 * These counters are updated from the i915 PMU sampling timer.
105 	 *
106 	 * Only global counters are held here, while the per-engine ones are in
107 	 * struct intel_engine_cs.
108 	 */
109 	struct i915_pmu_sample sample[__I915_NUM_PMU_SAMPLERS];
110 	/**
111 	 * @sleep_last: Last time GT parked for RC6 estimation.
112 	 */
113 	ktime_t sleep_last;
114 	/**
115 	 * @irq_count: Number of interrupts
116 	 *
117 	 * Intentionally unsigned long to avoid atomics or heuristics on 32bit.
118 	 * 4e9 interrupts are a lot and postprocessing can really deal with an
119 	 * occasional wraparound easily. It's 32bit after all.
120 	 */
121 	unsigned long irq_count;
122 	/**
123 	 * @events_attr_group: Device events attribute group.
124 	 */
125 	struct attribute_group events_attr_group;
126 	/**
127 	 * @i915_attr: Memory block holding device attributes.
128 	 */
129 	void *i915_attr;
130 	/**
131 	 * @pmu_attr: Memory block holding device attributes.
132 	 */
133 	void *pmu_attr;
134 };
135 
136 #ifdef CONFIG_PERF_EVENTS
137 void i915_pmu_init(void);
138 void i915_pmu_exit(void);
139 void i915_pmu_register(struct drm_i915_private *i915);
140 void i915_pmu_unregister(struct drm_i915_private *i915);
141 void i915_pmu_gt_parked(struct drm_i915_private *i915);
142 void i915_pmu_gt_unparked(struct drm_i915_private *i915);
143 #else
144 static inline void i915_pmu_init(void) {}
145 static inline void i915_pmu_exit(void) {}
146 static inline void i915_pmu_register(struct drm_i915_private *i915) {}
147 static inline void i915_pmu_unregister(struct drm_i915_private *i915) {}
148 static inline void i915_pmu_gt_parked(struct drm_i915_private *i915) {}
149 static inline void i915_pmu_gt_unparked(struct drm_i915_private *i915) {}
150 #endif
151 
152 #endif
153