[PATCH] kernel: convert switch/case fallthrough comments to fallthrough;

[Joe Perches <joe@perches.com>]

Use the new pseudo keyword "fallthrough;" and not the
various /* fallthrough */ style comments.

Signed-off-by: Joe Perches <joe@perches.com>
---

This is a single patch for the kernel/ source tree,
which would otherwise
be sent through as separate
patches to 19 maintainer sections.

compilation tested only.

Done by the script in this email:
https://lore.kernel.org/lkml/9fe980f7e28242c2835ffae34914c5f68e8268a7.camel@perches.com/

 kernel/auditfilter.c               | 2 +-
 kernel/bpf/cgroup.c                | 4 ++--
 kernel/bpf/verifier.c              | 4 ++--
 kernel/capability.c                | 2 +-
 kernel/compat.c                    | 6 +++---
 kernel/debug/gdbstub.c             | 6 +++---
 kernel/debug/kdb/kdb_keyboard.c    | 4 ++--
 kernel/debug/kdb/kdb_support.c     | 6 +++---
 kernel/events/core.c               | 3 +--
 kernel/futex.c                     | 4 ++--
 kernel/gcov/gcc_3_4.c              | 6 +++---
 kernel/irq/handle.c                | 3 +--
 kernel/irq/manage.c                | 5 ++---
 kernel/kallsyms.c                  | 4 ++--
 kernel/pid.c                       | 2 +-
 kernel/power/hibernate.c           | 2 +-
 kernel/power/qos.c                 | 4 ++--
 kernel/printk/printk.c             | 2 +-
 kernel/sched/core.c                | 2 +-
 kernel/sched/topology.c            | 6 +++---
 kernel/signal.c                    | 2 +-
 kernel/sys.c                       | 3 +--
 kernel/time/hrtimer.c              | 2 +-
 kernel/time/posix-timers.c         | 4 ++--
 kernel/time/tick-broadcast.c       | 2 +-
 kernel/time/timer.c                | 2 +-
 kernel/trace/blktrace.c            | 2 +-
 kernel/trace/trace_events_filter.c | 4 ++--
 28 files changed, 47 insertions(+), 51 deletions(-)

diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c
index b0126e9c0743..471cd680479d 100644
--- a/kernel/auditfilter.c
+++ b/kernel/auditfilter.c
@@ -674,7 +674,7 @@ static struct audit_rule_data *audit_krule_to_data(struct audit_krule *krule)
 				data->values[i] = AUDIT_UID_UNSET;
 				break;
 			}
-			/* fall through - if set */
+			fallthrough;	/* if set */
 		default:
 			data->values[i] = f->val;
 		}
diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c
index ddd8addcdb5c..955631f1b77d 100644
--- a/kernel/bpf/cgroup.c
+++ b/kernel/bpf/cgroup.c
@@ -797,7 +797,7 @@ cgroup_base_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
 	case BPF_FUNC_trace_printk:
 		if (capable(CAP_SYS_ADMIN))
 			return bpf_get_trace_printk_proto();
-		/* fall through */
+		fallthrough;
 	default:
 		return NULL;
 	}
@@ -1439,7 +1439,7 @@ static bool cg_sockopt_is_valid_access(int off, int size,
 			return prog->expected_attach_type ==
 				BPF_CGROUP_GETSOCKOPT;
 		case offsetof(struct bpf_sockopt, optname):
-			/* fallthrough */
+			fallthrough;
 		case offsetof(struct bpf_sockopt, level):
 			if (size != size_default)
 				return false;
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index ffc3e53f5300..d2b6fd8545e2 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -2249,7 +2249,7 @@ static bool may_access_direct_pkt_data(struct bpf_verifier_env *env,
 	case BPF_PROG_TYPE_CGROUP_SKB:
 		if (t == BPF_WRITE)
 			return false;
-		/* fallthrough */
+		fallthrough;
 
 	/* Program types with direct read + write access go here! */
 	case BPF_PROG_TYPE_SCHED_CLS:
@@ -4381,7 +4381,7 @@ static int adjust_ptr_min_max_vals(struct bpf_verifier_env *env,
 				off_reg == dst_reg ? dst : src);
 			return -EACCES;
 		}
-		/* fall-through */
+		fallthrough;
 	default:
 		break;
 	}
diff --git a/kernel/capability.c b/kernel/capability.c
index 1444f3954d75..7c59b096c98a 100644
--- a/kernel/capability.c
+++ b/kernel/capability.c
@@ -93,7 +93,7 @@ static int cap_validate_magic(cap_user_header_t header, unsigned *tocopy)
 		break;
 	case _LINUX_CAPABILITY_VERSION_2:
 		warn_deprecated_v2();
-		/* fall through - v3 is otherwise equivalent to v2. */
+		fallthrough;	/* v3 is otherwise equivalent to v2 */
 	case _LINUX_CAPABILITY_VERSION_3:
 		*tocopy = _LINUX_CAPABILITY_U32S_3;
 		break;
diff --git a/kernel/compat.c b/kernel/compat.c
index a2bc1d6ceb57..d9c61f4317be 100644
--- a/kernel/compat.c
+++ b/kernel/compat.c
@@ -343,11 +343,11 @@ get_compat_sigset(sigset_t *set, const compat_sigset_t __user *compat)
 		return -EFAULT;
 	switch (_NSIG_WORDS) {
 	case 4: set->sig[3] = v.sig[6] | (((long)v.sig[7]) << 32 );
-		/* fall through */
+		fallthrough;
 	case 3: set->sig[2] = v.sig[4] | (((long)v.sig[5]) << 32 );
-		/* fall through */
+		fallthrough;
 	case 2: set->sig[1] = v.sig[2] | (((long)v.sig[3]) << 32 );
-		/* fall through */
+		fallthrough;
 	case 1: set->sig[0] = v.sig[0] | (((long)v.sig[1]) << 32 );
 	}
 #else
diff --git a/kernel/debug/gdbstub.c b/kernel/debug/gdbstub.c
index 4b280fc7dd67..b9d8b7248964 100644
--- a/kernel/debug/gdbstub.c
+++ b/kernel/debug/gdbstub.c
@@ -1033,14 +1033,14 @@ int gdb_serial_stub(struct kgdb_state *ks)
 				return DBG_PASS_EVENT;
 			}
 #endif
-			/* Fall through */
+			fallthrough;
 		case 'C': /* Exception passing */
 			tmp = gdb_cmd_exception_pass(ks);
 			if (tmp > 0)
 				goto default_handle;
 			if (tmp == 0)
 				break;
-			/* Fall through - on tmp < 0 */
+			fallthrough;	/* on tmp < 0 */
 		case 'c': /* Continue packet */
 		case 's': /* Single step packet */
 			if (kgdb_contthread && kgdb_contthread != current) {
@@ -1049,7 +1049,7 @@ int gdb_serial_stub(struct kgdb_state *ks)
 				break;
 			}
 			dbg_activate_sw_breakpoints();
-			/* Fall through - to default processing */
+			fallthrough;	/* to default processing */
 		default:
 default_handle:
 			error = kgdb_arch_handle_exception(ks->ex_vector,
diff --git a/kernel/debug/kdb/kdb_keyboard.c b/kernel/debug/kdb/kdb_keyboard.c
index 750497b0003a..f877a0a0d7cf 100644
--- a/kernel/debug/kdb/kdb_keyboard.c
+++ b/kernel/debug/kdb/kdb_keyboard.c
@@ -173,11 +173,11 @@ int kdb_get_kbd_char(void)
 	case KT_LATIN:
 		if (isprint(keychar))
 			break;		/* printable characters */
-		/* fall through */
+		fallthrough;
 	case KT_SPEC:
 		if (keychar == K_ENTER)
 			break;
-		/* fall through */
+		fallthrough;
 	default:
 		return -1;	/* ignore unprintables */
 	}
diff --git a/kernel/debug/kdb/kdb_support.c b/kernel/debug/kdb/kdb_support.c
index b8e6306e7e13..d636506f695a 100644
--- a/kernel/debug/kdb/kdb_support.c
+++ b/kernel/debug/kdb/kdb_support.c
@@ -432,7 +432,7 @@ int kdb_getphysword(unsigned long *word, unsigned long addr, size_t size)
 				*word = w8;
 			break;
 		}
-		/* fall through */
+		fallthrough;
 	default:
 		diag = KDB_BADWIDTH;
 		kdb_printf("kdb_getphysword: bad width %ld\n", (long) size);
@@ -481,7 +481,7 @@ int kdb_getword(unsigned long *word, unsigned long addr, size_t size)
 				*word = w8;
 			break;
 		}
-		/* fall through */
+		fallthrough;
 	default:
 		diag = KDB_BADWIDTH;
 		kdb_printf("kdb_getword: bad width %ld\n", (long) size);
@@ -525,7 +525,7 @@ int kdb_putword(unsigned long addr, unsigned long word, size_t size)
 			diag = kdb_putarea(addr, w8);
 			break;
 		}
-		/* fall through */
+		fallthrough;
 	default:
 		diag = KDB_BADWIDTH;
 		kdb_printf("kdb_putword: bad width %ld\n", (long) size);
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 9ec0b0bfddbd..04e75b1144c5 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -9361,8 +9361,7 @@ perf_event_parse_addr_filter(struct perf_event *event, char *fstr,
 		case IF_SRC_KERNELADDR:
 		case IF_SRC_KERNEL:
 			kernel = 1;
-			/* fall through */
-
+			fallthrough;
 		case IF_SRC_FILEADDR:
 		case IF_SRC_FILE:
 			if (state != IF_STATE_SOURCE)
diff --git a/kernel/futex.c b/kernel/futex.c
index bd18f60e4c6c..ab12b6229d2d 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -3639,12 +3639,12 @@ long do_futex(u32 __user *uaddr, int op, u32 val, ktime_t *timeout,
 	switch (cmd) {
 	case FUTEX_WAIT:
 		val3 = FUTEX_BITSET_MATCH_ANY;
-		/* fall through */
+		fallthrough;
 	case FUTEX_WAIT_BITSET:
 		return futex_wait(uaddr, flags, val, timeout, val3);
 	case FUTEX_WAKE:
 		val3 = FUTEX_BITSET_MATCH_ANY;
-		/* fall through */
+		fallthrough;
 	case FUTEX_WAKE_BITSET:
 		return futex_wake(uaddr, flags, val, val3);
 	case FUTEX_REQUEUE:
diff --git a/kernel/gcov/gcc_3_4.c b/kernel/gcov/gcc_3_4.c
index 801ee4b0b969..32fc3278166f 100644
--- a/kernel/gcov/gcc_3_4.c
+++ b/kernel/gcov/gcc_3_4.c
@@ -455,7 +455,7 @@ int gcov_iter_next(struct gcov_iterator *iter)
 	case RECORD_COUNT:
 		/* Advance to next count */
 		iter->count++;
-		/* fall through */
+		fallthrough;
 	case RECORD_COUNT_LEN:
 		if (iter->count < get_func(iter)->n_ctrs[iter->type]) {
 			iter->record = 9;
@@ -465,7 +465,7 @@ int gcov_iter_next(struct gcov_iterator *iter)
 		get_type(iter)->offset += iter->count;
 		iter->count = 0;
 		iter->type++;
-		/* fall through */
+		fallthrough;
 	case RECORD_FUNCTION_CHECK:
 		if (iter->type < iter->num_types) {
 			iter->record = 7;
@@ -474,7 +474,7 @@ int gcov_iter_next(struct gcov_iterator *iter)
 		/* Advance to next function */
 		iter->type = 0;
 		iter->function++;
-		/* fall through */
+		fallthrough;
 	case RECORD_TIME_STAMP:
 		if (iter->function < iter->info->n_functions)
 			iter->record = 3;
diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c
index a4ace611f47f..b38d2fd70fe1 100644
--- a/kernel/irq/handle.c
+++ b/kernel/irq/handle.c
@@ -165,8 +165,7 @@ irqreturn_t __handle_irq_event_percpu(struct irq_desc *desc, unsigned int *flags
 			}
 
 			__irq_wake_thread(desc, action);
-
-			/* Fall through - to add to randomness */
+			fallthrough;	/* to add to randomness */
 		case IRQ_HANDLED:
 			*flags |= action->flags;
 			break;
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 1753486b440c..baa86020f243 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -222,7 +222,7 @@ int irq_do_set_affinity(struct irq_data *data, const struct cpumask *mask,
 	case IRQ_SET_MASK_OK:
 	case IRQ_SET_MASK_OK_DONE:
 		cpumask_copy(desc->irq_common_data.affinity, mask);
-		/* fall through */
+		fallthrough;
 	case IRQ_SET_MASK_OK_NOCOPY:
 		irq_validate_effective_affinity(data);
 		irq_set_thread_affinity(desc);
@@ -792,8 +792,7 @@ int __irq_set_trigger(struct irq_desc *desc, unsigned long flags)
 	case IRQ_SET_MASK_OK_DONE:
 		irqd_clear(&desc->irq_data, IRQD_TRIGGER_MASK);
 		irqd_set(&desc->irq_data, flags);
-		/* fall through */
-
+		fallthrough;
 	case IRQ_SET_MASK_OK_NOCOPY:
 		flags = irqd_get_trigger_type(&desc->irq_data);
 		irq_settings_set_trigger_mask(desc, flags);
diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c
index 136ce049c4ad..05ce8a4d4729 100644
--- a/kernel/kallsyms.c
+++ b/kernel/kallsyms.c
@@ -651,11 +651,11 @@ int kallsyms_show_value(void)
 	case 0:
 		if (kallsyms_for_perf())
 			return 1;
-	/* fallthrough */
+		fallthrough;
 	case 1:
 		if (has_capability_noaudit(current, CAP_SYSLOG))
 			return 1;
-	/* fallthrough */
+		fallthrough;
 	default:
 		return 0;
 	}
diff --git a/kernel/pid.c b/kernel/pid.c
index 0a9f2e437217..b2a005a6dea1 100644
--- a/kernel/pid.c
+++ b/kernel/pid.c
@@ -144,7 +144,7 @@ void free_pid(struct pid *pid)
 			/* Handle a fork failure of the first process */
 			WARN_ON(ns->child_reaper);
 			ns->pid_allocated = 0;
-			/* fall through */
+			fallthrough;
 		case 0:
 			schedule_work(&ns->proc_work);
 			break;
diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
index 3c0a5a8170b0..d091dcd57557 100644
--- a/kernel/power/hibernate.c
+++ b/kernel/power/hibernate.c
@@ -647,7 +647,7 @@ static void power_down(void)
 		break;
 	case HIBERNATION_PLATFORM:
 		hibernation_platform_enter();
-		/* Fall through */
+		fallthrough;
 	case HIBERNATION_SHUTDOWN:
 		if (pm_power_off)
 			kernel_power_off();
diff --git a/kernel/power/qos.c b/kernel/power/qos.c
index 9568a2fe7c11..6bf5295b2ade 100644
--- a/kernel/power/qos.c
+++ b/kernel/power/qos.c
@@ -236,7 +236,7 @@ int pm_qos_update_target(struct pm_qos_constraints *c, struct plist_node *node,
 		 * changed
 		 */
 		plist_del(node, &c->list);
-		/* fall through */
+		fallthrough;
 	case PM_QOS_ADD_REQ:
 		plist_node_init(node, new_value);
 		plist_add(node, &c->list);
@@ -309,7 +309,7 @@ bool pm_qos_update_flags(struct pm_qos_flags *pqf,
 		break;
 	case PM_QOS_UPDATE_REQ:
 		pm_qos_flags_remove_req(pqf, req);
-		/* fall through */
+		fallthrough;
 	case PM_QOS_ADD_REQ:
 		req->flags = val;
 		INIT_LIST_HEAD(&req->node);
diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index ca65327a6de8..6b3d7c68e6fe 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -1531,7 +1531,7 @@ int do_syslog(int type, char __user *buf, int len, int source)
 	/* Read/clear last kernel messages */
 	case SYSLOG_ACTION_READ_CLEAR:
 		clear = true;
-		/* FALL THRU */
+		fallthrough;
 	/* Read last kernel messages */
 	case SYSLOG_ACTION_READ_ALL:
 		if (!buf || len < 0)
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index dd05a378631a..050b728728f4 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -2068,7 +2068,7 @@ static int select_fallback_rq(int cpu, struct task_struct *p)
 				state = possible;
 				break;
 			}
-			/* Fall-through */
+			fallthrough;
 		case possible:
 			do_set_cpus_allowed(p, cpu_possible_mask);
 			state = fail;
diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c
index b5667a273bf6..7d6b84e0caca 100644
--- a/kernel/sched/topology.c
+++ b/kernel/sched/topology.c
@@ -1224,13 +1224,13 @@ static void __free_domain_allocs(struct s_data *d, enum s_alloc what,
 	case sa_rootdomain:
 		if (!atomic_read(&d->rd->refcount))
 			free_rootdomain(&d->rd->rcu);
-		/* Fall through */
+		fallthrough;
 	case sa_sd:
 		free_percpu(d->sd);
-		/* Fall through */
+		fallthrough;
 	case sa_sd_storage:
 		__sdt_free(cpu_map);
-		/* Fall through */
+		fallthrough;
 	case sa_none:
 		break;
 	}
diff --git a/kernel/signal.c b/kernel/signal.c
index c4da1ef56fdf..73bdcc1f2561 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -846,7 +846,7 @@ static int check_kill_permission(int sig, struct kernel_siginfo *info,
 			 */
 			if (!sid || sid == task_session(current))
 				break;
-			/* fall through */
+			fallthrough;
 		default:
 			return -EPERM;
 		}
diff --git a/kernel/sys.c b/kernel/sys.c
index a611d1d58c7d..bad4f30e7f37 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -1737,8 +1737,7 @@ void getrusage(struct task_struct *p, int who, struct rusage *r)
 
 		if (who == RUSAGE_CHILDREN)
 			break;
-		/* fall through */
-
+		fallthrough;
 	case RUSAGE_SELF:
 		thread_group_cputime_adjusted(p, &tgutime, &tgstime);
 		utime += tgutime;
diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index 0d4dc241c0fb..8060a35682e1 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -373,7 +373,7 @@ static bool hrtimer_fixup_activate(void *addr, enum debug_obj_state state)
 	switch (state) {
 	case ODEBUG_STATE_ACTIVE:
 		WARN_ON(1);
-		/* fall through */
+		fallthrough;
 	default:
 		return false;
 	}
diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
index 0ec5b7a1d769..6cc658391702 100644
--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -413,12 +413,12 @@ static struct pid *good_sigevent(sigevent_t * event)
 		rtn = pid_task(pid, PIDTYPE_PID);
 		if (!rtn || !same_thread_group(rtn, current))
 			return NULL;
-		/* FALLTHRU */
+		fallthrough;
 	case SIGEV_SIGNAL:
 	case SIGEV_THREAD:
 		if (event->sigev_signo <= 0 || event->sigev_signo > SIGRTMAX)
 			return NULL;
-		/* FALLTHRU */
+		fallthrough;
 	case SIGEV_NONE:
 		return pid;
 	default:
diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c
index e51778c312f1..36d7464c8962 100644
--- a/kernel/time/tick-broadcast.c
+++ b/kernel/time/tick-broadcast.c
@@ -381,7 +381,7 @@ void tick_broadcast_control(enum tick_broadcast_mode mode)
 	switch (mode) {
 	case TICK_BROADCAST_FORCE:
 		tick_broadcast_forced = 1;
-		/* fall through */
+		fallthrough;
 	case TICK_BROADCAST_ON:
 		cpumask_set_cpu(cpu, tick_broadcast_on);
 		if (!cpumask_test_and_set_cpu(cpu, tick_broadcast_mask)) {
diff --git a/kernel/time/timer.c b/kernel/time/timer.c
index 4820823515e9..6512d721ef57 100644
--- a/kernel/time/timer.c
+++ b/kernel/time/timer.c
@@ -653,7 +653,7 @@ static bool timer_fixup_activate(void *addr, enum debug_obj_state state)
 
 	case ODEBUG_STATE_ACTIVE:
 		WARN_ON(1);
-		/* fall through */
+		fallthrough;
 	default:
 		return false;
 	}
diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index 2d6e93ab0478..0a1753dc69d3 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -717,7 +717,7 @@ int blk_trace_ioctl(struct block_device *bdev, unsigned cmd, char __user *arg)
 #endif
 	case BLKTRACESTART:
 		start = 1;
-		/* fall through */
+		fallthrough;
 	case BLKTRACESTOP:
 		ret = __blk_trace_startstop(q, start);
 		break;
diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
index c9a74f82b14a..78b0bfc4d72e 100644
--- a/kernel/trace/trace_events_filter.c
+++ b/kernel/trace/trace_events_filter.c
@@ -499,7 +499,7 @@ predicate_parse(const char *str, int nr_parens, int nr_preds,
 					ptr++;
 					break;
 				}
-				/* fall through */
+				fallthrough;
 			default:
 				parse_error(pe, FILT_ERR_TOO_MANY_PREDS,
 					    next - str);
@@ -1273,7 +1273,7 @@ static int parse_pred(const char *str, void *data,
 		switch (op) {
 		case OP_NE:
 			pred->not = 1;
-			/* Fall through */
+			fallthrough;
 		case OP_GLOB:
 		case OP_EQ:
 			break;