drivers/md/dm-vdo/statistics.h
Source file repositories/reference/linux-study-clean/drivers/md/dm-vdo/statistics.h
File Facts
- System
- Linux kernel
- Corpus path
drivers/md/dm-vdo/statistics.h- Extension
.h- Size
- 8934 bytes
- Lines
- 279
- Domain
- Driver Families
- Bucket
- drivers/md
- Inferred role
- Driver Families: implementation source
- Status
- source 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.
- Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.
Dependency Surface
types.h
Detected Declarations
struct block_allocator_statisticsstruct commit_statisticsstruct recovery_journal_statisticsstruct packer_statisticsstruct slab_journal_statisticsstruct slab_summary_statisticsstruct ref_counts_statisticsstruct block_map_statisticsstruct hash_lock_statisticsstruct error_statisticsstruct bio_statsstruct memory_usagestruct index_statisticsstruct vdo_statistics
Annotated Snippet
struct block_allocator_statistics {
/* The total number of slabs from which blocks may be allocated */
u64 slab_count;
/* The total number of slabs from which blocks have ever been allocated */
u64 slabs_opened;
/* The number of times since loading that a slab has been re-opened */
u64 slabs_reopened;
};
/**
* Counters for tracking the number of items written (blocks, requests, etc.)
* that keep track of totals at steps in the write pipeline. Three counters
* allow the number of buffered, in-memory items and the number of in-flight,
* unacknowledged writes to be derived, while still tracking totals for
* reporting purposes
*/
struct commit_statistics {
/* The total number of items on which processing has started */
u64 started;
/* The total number of items for which a write operation has been issued */
u64 written;
/* The total number of items for which a write operation has completed */
u64 committed;
};
/** Counters for events in the recovery journal */
struct recovery_journal_statistics {
/* Number of times the on-disk journal was full */
u64 disk_full;
/* Number of times the recovery journal requested slab journal commits. */
u64 slab_journal_commits_requested;
/* Write/Commit totals for individual journal entries */
struct commit_statistics entries;
/* Write/Commit totals for journal blocks */
struct commit_statistics blocks;
};
/** The statistics for the compressed block packer. */
struct packer_statistics {
/* Number of compressed data items written since startup */
u64 compressed_fragments_written;
/* Number of blocks containing compressed items written since startup */
u64 compressed_blocks_written;
/* Number of VIOs that are pending in the packer */
u64 compressed_fragments_in_packer;
};
/** The statistics for the slab journals. */
struct slab_journal_statistics {
/* Number of times the on-disk journal was full */
u64 disk_full_count;
/* Number of times an entry was added over the flush threshold */
u64 flush_count;
/* Number of times an entry was added over the block threshold */
u64 blocked_count;
/* Number of times a tail block was written */
u64 blocks_written;
/* Number of times we had to wait for the tail to write */
u64 tail_busy_count;
};
/** The statistics for the slab summary. */
struct slab_summary_statistics {
/* Number of blocks written */
u64 blocks_written;
};
/** The statistics for the reference counts. */
struct ref_counts_statistics {
/* Number of reference blocks written */
u64 blocks_written;
};
/** The statistics for the block map. */
struct block_map_statistics {
/* number of dirty (resident) pages */
u32 dirty_pages;
/* number of clean (resident) pages */
u32 clean_pages;
/* number of free pages */
u32 free_pages;
/* number of pages in failed state */
u32 failed_pages;
/* number of pages incoming */
u32 incoming_pages;
/* number of pages outgoing */
u32 outgoing_pages;
/* how many times free page not avail */
u32 cache_pressure;
/* number of get_vdo_page() calls for read */
Annotation
- Immediate include surface: `types.h`.
- Detected declarations: `struct block_allocator_statistics`, `struct commit_statistics`, `struct recovery_journal_statistics`, `struct packer_statistics`, `struct slab_journal_statistics`, `struct slab_summary_statistics`, `struct ref_counts_statistics`, `struct block_map_statistics`, `struct hash_lock_statistics`, `struct error_statistics`.
- Atlas domain: Driver Families / drivers/md.
- Implementation status: source implementation candidate.
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.