block/blk-iocost.c

File Facts

System

Linux kernel

Corpus path

block/blk-iocost.c

Extension

.c

Size

102757 bytes

Lines

3601

Domain

Representative Device Path

Bucket

PCIe NVMe Storage Path

Inferred role

Representative Device Path: exported/initcall integration point

Status

integration implementation candidate

Why This File Exists

Part of the selected hardware vertical slice: PCI discovery, driver binding, NVMe queues, block requests, DMA, interrupts, and completion.

• Part of the selected hardware vertical slice: PCI discovery, driver binding, NVMe queues, block requests, DMA, interrupts, and completion.
• 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/kernel.h
• linux/module.h
• linux/timer.h
• linux/time64.h
• linux/parser.h
• linux/sched/signal.h
• asm/local.h
• asm/local64.h
• blk-rq-qos.h
• blk-stat.h
• blk-wbt.h
• blk-cgroup.h
• trace/events/iocost.h

Detected Declarations

• struct ioc_params
• struct ioc_margins
• struct ioc_missed
• struct ioc_pcpu_stat
• struct ioc
• struct iocg_pcpu_stat
• struct iocg_stat
• struct ioc_gq
• struct ioc_cgrp
• struct ioc_now
• struct iocg_wait
• struct iocg_wake_ctx
• enum ioc_running
• enum over_budget_action
• function abs_cost_to_cost
• function abs_cost_to_cost
• function iocg_commit_bio
• function ioc_refresh_margins
• function ioc_refresh_period_us
• function ioc_autop_idx
• function calc_lcoefs
• function ioc_refresh_lcoefs
• function ioc_refresh_params_disk
• function ioc_refresh_params
• function ioc_refresh_vrate
• function ioc_adjust_base_vrate
• function ioc_now
• function ioc_start_period
• function __propagate_weights
• function commit_weights
• function propagate_weights
• function current_hweight
• function current_hweight_max
• function weight_updated
• function iocg_activate
• function iocg_kick_delay
• function iocg_incur_debt
• function iocg_pay_debt
• function iocg_wake_fn
• function iocg_kick_waitq
• function iocg_waitq_timer_fn
• function ioc_lat_stat
• function for_each_online_cpu
• function iocg_is_idle
• function iocg_build_inner_walk
• function iocg_flush_stat_upward
• function iocg_flush_stat_leaf
• function iocg_flush_stat

Annotated Snippet

module_init(ioc_init);
module_exit(ioc_exit);

Annotation

• Immediate include surface: `linux/kernel.h`, `linux/module.h`, `linux/timer.h`, `linux/time64.h`, `linux/parser.h`, `linux/sched/signal.h`, `asm/local.h`, `asm/local64.h`.
• Detected declarations: `struct ioc_params`, `struct ioc_margins`, `struct ioc_missed`, `struct ioc_pcpu_stat`, `struct ioc`, `struct iocg_pcpu_stat`, `struct iocg_stat`, `struct ioc_gq`, `struct ioc_cgrp`, `struct ioc_now`.
• Atlas domain: Representative Device Path / PCIe NVMe Storage Path.
• 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.