include/linux/hrtimer_defs.h
Source file repositories/reference/linux-study-clean/include/linux/hrtimer_defs.h
File Facts
- System
- Linux kernel
- Corpus path
include/linux/hrtimer_defs.h- Extension
.h- Size
- 4002 bytes
- Lines
- 114
- Domain
- Core OS
- Bucket
- Core Kernel Interface
- Inferred role
- Core OS: implementation source
- Status
- source implementation candidate
Why This File Exists
Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.
- Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.
- Uses kernel synchronization; read lock ordering, sleepability, and interrupt context assumptions before translating.
- Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.
Dependency Surface
linux/ktime.hlinux/timerqueue.hlinux/seqlock.h
Detected Declarations
struct hrtimer_clock_basestruct hrtimer_cpu_baseenum hrtimer_base_type
Annotated Snippet
struct hrtimer_clock_base {
struct hrtimer_cpu_base *cpu_base;
const unsigned int index;
const clockid_t clockid;
seqcount_raw_spinlock_t seq;
ktime_t expires_next;
struct hrtimer *running;
struct timerqueue_linked_head active;
ktime_t offset;
} __hrtimer_clock_base_align;
enum hrtimer_base_type {
HRTIMER_BASE_MONOTONIC,
HRTIMER_BASE_REALTIME,
HRTIMER_BASE_BOOTTIME,
HRTIMER_BASE_TAI,
HRTIMER_BASE_MONOTONIC_SOFT,
HRTIMER_BASE_REALTIME_SOFT,
HRTIMER_BASE_BOOTTIME_SOFT,
HRTIMER_BASE_TAI_SOFT,
HRTIMER_MAX_CLOCK_BASES
};
/**
* struct hrtimer_cpu_base - the per cpu clock bases
* @lock: lock protecting the base and associated clock bases and timers
* @cpu: cpu number
* @active_bases: Bitfield to mark bases with active timers
* @clock_was_set_seq: Sequence counter of clock was set events
* @hres_active: State of high resolution mode
* @deferred_rearm: A deferred rearm is pending
* @deferred_needs_update: The deferred rearm must re-evaluate the first timer
* @hang_detected: The last hrtimer interrupt detected a hang
* @softirq_activated: displays, if the softirq is raised - update of softirq
* related settings is not required then.
* @nr_events: Total number of hrtimer interrupt events
* @nr_retries: Total number of hrtimer interrupt retries
* @nr_hangs: Total number of hrtimer interrupt hangs
* @max_hang_time: Maximum time spent in hrtimer_interrupt
* @softirq_expiry_lock: Lock which is taken while softirq based hrtimer are expired
* @online: CPU is online from an hrtimers point of view
* @timer_waiters: A hrtimer_cancel() waiters for the timer callback to finish.
* @expires_next: Absolute time of the next event, is required for remote
* hrtimer enqueue; it is the total first expiry time (hard
* and soft hrtimer are taken into account)
* @next_timer: Pointer to the first expiring timer
* @softirq_expires_next: Time to check, if soft queues needs also to be expired
* @softirq_next_timer: Pointer to the first expiring softirq based timer
* @deferred_expires_next: Cached expires next value for deferred rearm
* @clock_base: Array of clock bases for this cpu
*
* Note: next_timer is just an optimization for __remove_hrtimer().
* Do not dereference the pointer because it is not reliable on
* cross cpu removals.
*/
struct hrtimer_cpu_base {
raw_spinlock_t lock;
unsigned int cpu;
unsigned int active_bases;
unsigned int clock_was_set_seq;
bool hres_active;
bool deferred_rearm;
bool deferred_needs_update;
bool hang_detected;
bool softirq_activated;
bool online;
#ifdef CONFIG_HIGH_RES_TIMERS
unsigned int nr_events;
unsigned short nr_retries;
unsigned short nr_hangs;
unsigned int max_hang_time;
#endif
#ifdef CONFIG_PREEMPT_RT
spinlock_t softirq_expiry_lock;
atomic_t timer_waiters;
#endif
ktime_t expires_next;
struct hrtimer *next_timer;
ktime_t softirq_expires_next;
struct hrtimer *softirq_next_timer;
ktime_t deferred_expires_next;
struct hrtimer_clock_base clock_base[HRTIMER_MAX_CLOCK_BASES];
call_single_data_t csd;
} ____cacheline_aligned;
#endif
Annotation
- Immediate include surface: `linux/ktime.h`, `linux/timerqueue.h`, `linux/seqlock.h`.
- Detected declarations: `struct hrtimer_clock_base`, `struct hrtimer_cpu_base`, `enum hrtimer_base_type`.
- Atlas domain: Core OS / Core Kernel Interface.
- Implementation status: source implementation candidate.
- Synchronization appears in or near this file; preserve lock ordering, sleepability, and interrupt-context constraints.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.