A sequence counter write side critical section must be protected by some form of locking to serialize writers. A plain seqcount_t does not contain the information of which lock must be held when entering a write side critical section. Use the new seqcount_raw_spinlock_t data type, which allows to associate a raw spinlock with the sequence counter. This enables lockdep to verify that the raw spinlock used for writer serialization is held when the write side critical section is entered. If lockdep is disabled this lock association is compiled out and has neither storage size nor runtime overhead.
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| @@ -159,7 +159,7 @@ struct hrtimer_clock_base { · 158 unmodified lines | |||
| 159 | struct hrtimer_cpu_base *cpu_base; | 159 | struct hrtimer_cpu_base *cpu_base; |
| 160 | unsigned int index; | 160 | unsigned int index; |
| 161 | clockid_t clockid; | 161 | clockid_t clockid; |
| 162 | seqcount_t seq; | 162 | seqcount_raw_spinlock_t seq; |
| 163 | struct hrtimer *running; | 163 | struct hrtimer *running; |
| 164 | struct timerqueue_head active; | 164 | struct timerqueue_head active; |
| 165 | ktime_t (*get_time)(void); | 165 | ktime_t (*get_time)(void); |