Documentation/core-api/genericirq.rst

File Facts

System

Linux kernel

Corpus path

Documentation/core-api/genericirq.rst

Extension

.rst

Size

12791 bytes

Lines

445

Domain

Support Tooling And Documentation

Bucket

Documentation

Inferred role

Support Tooling And Documentation: documentation

Status

atlas-only

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

• Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.
• Touches IRQ or DMA behavior; this matters for the representative real-device path.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• No C-style include directives detected by the generator.

Detected Declarations

• function __do_IRQ
• function default_disable
• function default_ack
• function default_mask_ack
• function noop
• function implemented

Annotated Snippet

if (chip->irq_mask_ack) {
            chip->irq_mask_ack(data);
        } else {
            chip->irq_mask(data);
            chip->irq_ack(data);
        }
    }

    noop(struct irq_data *data)
    {
    }



Default flow handler implementations
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Default Level IRQ flow handler
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

handle_level_irq provides a generic implementation for level-triggered
interrupts.

The following control flow is implemented (simplified excerpt)::

    desc->irq_data.chip->irq_mask_ack();
    handle_irq_event(desc->action);
    desc->irq_data.chip->irq_unmask();


Default Fast EOI IRQ flow handler
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

handle_fasteoi_irq provides a generic implementation for interrupts,
which only need an EOI at the end of the handler.

The following control flow is implemented (simplified excerpt)::

    handle_irq_event(desc->action);
    desc->irq_data.chip->irq_eoi();


Default Edge IRQ flow handler
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

handle_edge_irq provides a generic implementation for edge-triggered
interrupts.

The following control flow is implemented (simplified excerpt)::

    if (desc->status & running) {
        desc->irq_data.chip->irq_mask_ack();
        desc->status |= pending | masked;
        return;
    }
    desc->irq_data.chip->irq_ack();
    desc->status |= running;
    do {
        if (desc->status & masked)
            desc->irq_data.chip->irq_unmask();
        desc->status &= ~pending;
        handle_irq_event(desc->action);
    } while (desc->status & pending);
    desc->status &= ~running;


Default simple IRQ flow handler
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

handle_simple_irq provides a generic implementation for simple

Annotation

• Detected declarations: `function __do_IRQ`, `function default_disable`, `function default_ack`, `function default_mask_ack`, `function noop`, `function implemented`.
• Atlas domain: Support Tooling And Documentation / Documentation.
• Implementation status: atlas-only.
• IRQ or DMA behavior appears here, which is relevant to the selected PCIe/NVMe device path.

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.