tools/perf/dlfilters/dlfilter-show-cycles.c

File Facts

System

Linux kernel

Corpus path

tools/perf/dlfilters/dlfilter-show-cycles.c

Extension

.c

Size

2996 bytes

Lines

145

Domain

Support Tooling And Documentation

Bucket

tools

Inferred role

Support Tooling And Documentation: implementation source

Status

source implementation candidate

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.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• perf/perf_dlfilter.h
• string.h
• stdio.h

Detected Declarations

• function event_entry
• function add_entry
• function filter_event_early
• function print_vals
• function filter_event

Annotated Snippet

if (e) {
			print_vals(e->cycles[pos], e->cycles[pos] - e->cycles_rpt[pos]);
			e->cycles_rpt[pos] = e->cycles[pos];
			return 0;
		}
	}

	printf("%22s", "");
	return 0;
}

const char *filter_description(const char **long_description)
{
	static char *long_desc = "Cycle counts are accumulated per CPU (or "
		"per thread if CPU is not recorded) from IPC information, and "
		"printed together with the change since the last print, at the "
		"start of each line. Separate counts are kept for branches, "
		"instructions or other events.";

	*long_description = long_desc;
	return "Print the number of cycles at the start of each line";
}

Annotation

• Immediate include surface: `perf/perf_dlfilter.h`, `string.h`, `stdio.h`.
• Detected declarations: `function event_entry`, `function add_entry`, `function filter_event_early`, `function print_vals`, `function filter_event`.
• Atlas domain: Support Tooling And Documentation / tools.
• 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.