tools/objtool/trace.c

File Facts

System

Linux kernel

Corpus path

tools/objtool/trace.c

Extension

.c

Size

5444 bytes

Lines

204

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

• objtool/trace.h

Detected Declarations

• function trace_cfi_reg
• function trace_cfi_reg_val
• function trace_cfi_reg_ref
• function trace_insn_state
• function trace_alt_begin
• function trace_alt_end

Annotated Snippet

if (orig_insn->type == INSN_NOP) {
			suffix[0] = (orig_insn->len == 5) ? 'q' : '\0';
			TRACE_ADDR(orig_insn, "jmp%-3s %lx <%s+0x%lx>", suffix,
				   alt_insn->offset, insn_sym(alt_insn)->name,
				   alt_insn->offset - insn_sym(alt_insn)->offset);
		} else {
			TRACE_ADDR(orig_insn, "nop%d", orig_insn->len);
			trace_depth--;
		}
	}
}

void trace_alt_end(struct instruction *orig_insn, struct alternative *alt,
		   char *alt_name)
{
	if (alt->type == ALT_TYPE_JUMP_TABLE && orig_insn->type == INSN_NOP)
		trace_depth--;
	TRACE_ALT_INFO_NOADDR(orig_insn, "\\ ", "%s", alt_name);
}

Annotation

• Immediate include surface: `objtool/trace.h`.
• Detected declarations: `function trace_cfi_reg`, `function trace_cfi_reg_val`, `function trace_cfi_reg_ref`, `function trace_insn_state`, `function trace_alt_begin`, `function trace_alt_end`.
• 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.