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membarrier

Implemented in Antinomie 0.7.0 · Syscall list

long membarrier(int cmd, unsigned int flags, int cpu_id);
Number (x86-64) 324
ABI common
Kernel entry point sys_membarrier

This is the raw kernel prototype from the pinned Linux 6.12.94 schema, not the libc wrapper.

Issues memory barriers across all threads of a process, or reports supported commands.

Name Type Meaning
cmd (arg0) int Command or operation selector.
flags (arg1) unsigned int Option flags that change the behavior of the call.
cpu_id (arg2) int CPU id.

On success: a command-specific value.

In an Antinomie trace the Return column and the ret filter field show the raw kernel return value. On failure that is the negative errno, for example -2 for ENOENT, not the -1 plus errno that the libc wrapper gives. syscall.errno holds the positive errno and syscall.success is false.

Raw return Name Meaning
-22 EINVAL An argument is invalid.
-38 ENOSYS The system call is not implemented.

membarrier(2) on man7.org

Coverage mark: Implemented. All arguments are plain values, recorded as the raw argument words at entry. There is no pointee to copy and no known gap.

Every call is recorded as an Entry record (the six argument words and the pointees copied at entry) and an Exit record (the return value and the pointees copied at exit).

Argument When How Recorded field key Condition
cmd (arg0) Entry raw scalar word args.0, args.cmd
flags (arg1) Entry raw scalar word; Syscall Trace also decodes it into flag names (membarrier_flags group), listing unknown bits separately args.1, args.flags
cpu_id (arg2) Entry raw scalar word args.2, args.cpu_id
  • Result: ret, syscall.errno, syscall.success, syscall.duration_ns.
  • Argument words: args.cmd (arg0), args.flags (arg1), args.cpu_id (arg2); args.0 to args.5 by position.

See Syscall Trace filter for the full syntax.

For what the capture statuses mean, see Capture statuses. For what is never recorded, see Known gaps.