ioprio_set/ioprio_get: classify as Process family

Audit of ioprio_set found a family inconsistency. ioprio_set(which, who,
ioprio) and ioprio_get(which, who) query/set the I/O scheduling class and
priority of a process, process group, or user. They are the direct
I/O-priority analogues of getpriority/setpriority (the CPU nice value) and
share the identical which/who selector signature, yet were falling through to
FamilyMisc while getpriority/setpriority are FamilyProcess.

Reclassify both ioprio syscalls to FamilyProcess for consistency with their
priority siblings, update docs/syscall-tracing-plan.md, and regenerate the
tracepoint/type artifacts (mage generate is idempotent).

Argument capture is unchanged and confirmed correct: the args are all ints
(which/who/ioprio), none named fd/path, so ClassifyFormat returns KindNone and
the generator promotes the enter format to KindNull (null_event). In
particular the 'who' argument (a pid/pgid/uid, never an fd) is not
misclassified as KindFd. The exit is a ret_event (UNCLASSIFIED, int 0/-1).

Add lock-in tests:
- TestClassifyIoprioNullKind asserts KindNone/KindNull using the real kernel
  tracepoint fields, proving 'who' is not captured as an fd.
- Family assertions for the ioprio pair alongside getpriority/setpriority so a
  stray reclassification of any of them trips the test.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

1 files changed, 16 insertions, 0 deletions

diff --git a/internal/generate/family_test.go b/internal/generate/family_test.go
index af40e7d..47b7685 100644
--- a/internal/generate/family_test.go
+++ b/internal/generate/family_test.go
@@ -160,6 +160,22 @@ func TestClassifySyscallFamily(t *testing.T) {
 		{"sys_enter_rt_sigqueueinfo", FamilySignals},
 		{"sys_enter_rt_tgsigqueueinfo", FamilySignals},
 		{"sys_enter_sigaltstack", FamilySignals},
+		// ioprio_get/ioprio_set query/set the I/O scheduling class and priority of
+		// a process, process group, or user. They are the I/O-priority analogues of
+		// getpriority/setpriority (the CPU nice value) and share the identical
+		// which/who selector signature, so they classify as Process alongside them
+		// rather than falling through to Misc. Assert the ioprio pair together with
+		// their getpriority/setpriority siblings so a stray reclassification of any
+		// one of them trips this test. Note: the x86 I/O-port syscalls ioperm/iopl
+		// (asserted above as Misc) only share an "io" name prefix; they set
+		// port-access state, not process I/O priority, and stay in Misc. Keep in
+		// sync with the Process list in docs/syscall-tracing-plan.md.
+		{"sys_enter_ioprio_get", FamilyProcess},
+		{"sys_exit_ioprio_get", FamilyProcess},
+		{"sys_enter_ioprio_set", FamilyProcess},
+		{"sys_exit_ioprio_set", FamilyProcess},
+		{"sys_enter_getpriority", FamilyProcess},
+		{"sys_enter_setpriority", FamilyProcess},
 		{"sys_enter_unlisted_future_syscall", FamilyMisc},
 	}