drivers/ptp/ptp_vclock.c

File Facts

System

Linux kernel

Corpus path

drivers/ptp/ptp_vclock.c

Extension

.c

Size

7174 bytes

Lines

307

Domain

Driver Families

Bucket

drivers/ptp

Inferred role

Driver Families: exported/initcall integration point

Status

integration implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

• Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.
• Exports symbols or registers init work; inspect boot/module ordering and who consumes the exported contract.
• Uses kernel synchronization; read lock ordering, sleepability, and interrupt context assumptions before translating.
• Allocates kernel memory; connect allocation flags and lifetime to context constraints.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• linux/slab.h
• linux/hashtable.h
• ptp_private.h

Detected Declarations

• function ptp_vclock_hash_add
• function ptp_vclock_hash_del
• function ptp_vclock_adjfine
• function ptp_vclock_adjtime
• function ptp_vclock_gettime
• function ptp_vclock_gettimex
• function ptp_vclock_settime
• function ptp_vclock_getcrosststamp
• function ptp_vclock_refresh
• function ptp_vclock_set_subclass
• function ptp_vclock_read
• function ptp_vclock_unregister
• function ptp_get_vclocks_index
• function ptp_convert_timestamp
• function hlist_for_each_entry_srcu
• export ptp_get_vclocks_index
• export ptp_convert_timestamp

Annotated Snippet

srcu_read_lock_held(&vclock_srcu)) {
		if (vclock->clock->index != vclock_index)
			continue;

		if (mutex_lock_interruptible(&vclock->lock))
			break;
		vclock_ns = timecounter_cyc2time(&vclock->tc, ns);
		mutex_unlock(&vclock->lock);
		break;
	}

	srcu_read_unlock(&vclock_srcu, srcu_idx);

	return ns_to_ktime(vclock_ns);
}
EXPORT_SYMBOL(ptp_convert_timestamp);
#endif

Annotation

• Immediate include surface: `linux/slab.h`, `linux/hashtable.h`, `ptp_private.h`.
• Detected declarations: `function ptp_vclock_hash_add`, `function ptp_vclock_hash_del`, `function ptp_vclock_adjfine`, `function ptp_vclock_adjtime`, `function ptp_vclock_gettime`, `function ptp_vclock_gettimex`, `function ptp_vclock_settime`, `function ptp_vclock_getcrosststamp`, `function ptp_vclock_refresh`, `function ptp_vclock_set_subclass`.
• Atlas domain: Driver Families / drivers/ptp.
• Implementation status: integration 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.