treewide: Use fallthrough pseudo-keyword

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

7 files changed, 40 insertions, 37 deletions

diff --git a/include/linux/compat.h b/include/linux/compat.h
index d38c4d7e83bd..b354ce58966e 100644
--- a/include/linux/compat.h
+++ b/include/linux/compat.h
@@ -429,11 +429,11 @@ put_compat_sigset(compat_sigset_t __user *compat, const sigset_t *set,
 	compat_sigset_t v;
 	switch (_NSIG_WORDS) {
 	case 4: v.sig[7] = (set->sig[3] >> 32); v.sig[6] = set->sig[3];
-		/* fall through */
+		fallthrough;
 	case 3: v.sig[5] = (set->sig[2] >> 32); v.sig[4] = set->sig[2];
-		/* fall through */
+		fallthrough;
 	case 2: v.sig[3] = (set->sig[1] >> 32); v.sig[2] = set->sig[1];
-		/* fall through */
+		fallthrough;
 	case 1: v.sig[1] = (set->sig[0] >> 32); v.sig[0] = set->sig[0];
 	}
 	return copy_to_user(compat, &v, size) ? -EFAULT : 0;
diff --git a/include/linux/filter.h b/include/linux/filter.h
index 0a355b005bf4..ebfb7cfb65f1 100644
--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -1200,7 +1200,7 @@ static inline u16 bpf_anc_helper(const struct sock_filter *ftest)
 		BPF_ANCILLARY(RANDOM);
 		BPF_ANCILLARY(VLAN_TPID);
 		}
-		/* Fallthrough. */
+		fallthrough;
 	default:
 		return ftest->code;
 	}
diff --git a/include/linux/jhash.h b/include/linux/jhash.h
index 19ddd43aee68..cfb62e9f37be 100644
--- a/include/linux/jhash.h
+++ b/include/linux/jhash.h
@@ -86,17 +86,17 @@ static inline u32 jhash(const void *key, u32 length, u32 initval)
 	}
 	/* Last block: affect all 32 bits of (c) */
 	switch (length) {
-	case 12: c += (u32)k[11]<<24;	/* fall through */
-	case 11: c += (u32)k[10]<<16;	/* fall through */
-	case 10: c += (u32)k[9]<<8;	/* fall through */
-	case 9:  c += k[8];		/* fall through */
-	case 8:  b += (u32)k[7]<<24;	/* fall through */
-	case 7:  b += (u32)k[6]<<16;	/* fall through */
-	case 6:  b += (u32)k[5]<<8;	/* fall through */
-	case 5:  b += k[4];		/* fall through */
-	case 4:  a += (u32)k[3]<<24;	/* fall through */
-	case 3:  a += (u32)k[2]<<16;	/* fall through */
-	case 2:  a += (u32)k[1]<<8;	/* fall through */
+	case 12: c += (u32)k[11]<<24;	fallthrough;
+	case 11: c += (u32)k[10]<<16;	fallthrough;
+	case 10: c += (u32)k[9]<<8;	fallthrough;
+	case 9:  c += k[8];		fallthrough;
+	case 8:  b += (u32)k[7]<<24;	fallthrough;
+	case 7:  b += (u32)k[6]<<16;	fallthrough;
+	case 6:  b += (u32)k[5]<<8;	fallthrough;
+	case 5:  b += k[4];		fallthrough;
+	case 4:  a += (u32)k[3]<<24;	fallthrough;
+	case 3:  a += (u32)k[2]<<16;	fallthrough;
+	case 2:  a += (u32)k[1]<<8;	fallthrough;
 	case 1:  a += k[0];
 		 __jhash_final(a, b, c);
 	case 0: /* Nothing left to add */
@@ -132,8 +132,8 @@ static inline u32 jhash2(const u32 *k, u32 length, u32 initval)
 
 	/* Handle the last 3 u32's */
 	switch (length) {
-	case 3: c += k[2];	/* fall through */
-	case 2: b += k[1];	/* fall through */
+	case 3: c += k[2];	fallthrough;
+	case 2: b += k[1];	fallthrough;
 	case 1: a += k[0];
 		__jhash_final(a, b, c);
 	case 0:	/* Nothing left to add */
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 1983e08f5906..97c83773b6f0 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -157,11 +157,14 @@ static inline void __mm_zero_struct_page(struct page *page)
 
 	switch (sizeof(struct page)) {
 	case 80:
-		_pp[9] = 0;	/* fallthrough */
+		_pp[9] = 0;
+		fallthrough;
 	case 72:
-		_pp[8] = 0;	/* fallthrough */
+		_pp[8] = 0;
+		fallthrough;
 	case 64:
-		_pp[7] = 0;	/* fallthrough */
+		_pp[7] = 0;
+		fallthrough;
 	case 56:
 		_pp[6] = 0;
 		_pp[5] = 0;
diff --git a/include/linux/signal.h b/include/linux/signal.h
index 6bb1a3f0258c..7bbc0e9cf084 100644
--- a/include/linux/signal.h
+++ b/include/linux/signal.h
@@ -137,11 +137,11 @@ static inline void name(sigset_t *r, const sigset_t *a, const sigset_t *b) \
 		b3 = b->sig[3]; b2 = b->sig[2];				\
 		r->sig[3] = op(a3, b3);					\
 		r->sig[2] = op(a2, b2);					\
-		/* fall through */					\
+		fallthrough;						\
 	case 2:								\
 		a1 = a->sig[1]; b1 = b->sig[1];				\
 		r->sig[1] = op(a1, b1);					\
-		/* fall through */					\
+		fallthrough;						\
 	case 1:								\
 		a0 = a->sig[0]; b0 = b->sig[0];				\
 		r->sig[0] = op(a0, b0);					\
@@ -171,9 +171,9 @@ static inline void name(sigset_t *set)					\
 	switch (_NSIG_WORDS) {						\
 	case 4:	set->sig[3] = op(set->sig[3]);				\
 		set->sig[2] = op(set->sig[2]);				\
-		/* fall through */					\
+		fallthrough;						\
 	case 2:	set->sig[1] = op(set->sig[1]);				\
-		/* fall through */					\
+		fallthrough;						\
 	case 1:	set->sig[0] = op(set->sig[0]);				\
 		    break;						\
 	default:							\
@@ -194,7 +194,7 @@ static inline void sigemptyset(sigset_t *set)
 		memset(set, 0, sizeof(sigset_t));
 		break;
 	case 2: set->sig[1] = 0;
-		/* fall through */
+		fallthrough;
 	case 1:	set->sig[0] = 0;
 		break;
 	}
@@ -207,7 +207,7 @@ static inline void sigfillset(sigset_t *set)
 		memset(set, -1, sizeof(sigset_t));
 		break;
 	case 2: set->sig[1] = -1;
-		/* fall through */
+		fallthrough;
 	case 1:	set->sig[0] = -1;
 		break;
 	}
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 46881d902124..ab57cf787c1f 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -3745,19 +3745,19 @@ static inline bool __skb_metadata_differs(const struct sk_buff *skb_a,
 #define __it(x, op) (x -= sizeof(u##op))
 #define __it_diff(a, b, op) (*(u##op *)__it(a, op)) ^ (*(u##op *)__it(b, op))
 	case 32: diffs |= __it_diff(a, b, 64);
-		 /* fall through */
+		fallthrough;
 	case 24: diffs |= __it_diff(a, b, 64);
-		 /* fall through */
+		fallthrough;
 	case 16: diffs |= __it_diff(a, b, 64);
-		 /* fall through */
+		fallthrough;
 	case  8: diffs |= __it_diff(a, b, 64);
 		break;
 	case 28: diffs |= __it_diff(a, b, 64);
-		 /* fall through */
+		fallthrough;
 	case 20: diffs |= __it_diff(a, b, 64);
-		 /* fall through */
+		fallthrough;
 	case 12: diffs |= __it_diff(a, b, 64);
-		 /* fall through */
+		fallthrough;
 	case  4: diffs |= __it_diff(a, b, 32);
 		break;
 	}
diff --git a/include/math-emu/op-common.h b/include/math-emu/op-common.h
index adcc6a97db61..143568d64b20 100644
--- a/include/math-emu/op-common.h
+++ b/include/math-emu/op-common.h
@@ -308,7 +308,7 @@ do {									     \
 									     \
   case _FP_CLS_COMBINE(FP_CLS_NORMAL,FP_CLS_ZERO):			     \
     R##_e = X##_e;							     \
-	  /* Fall through */						     \
+	fallthrough;							     \
   case _FP_CLS_COMBINE(FP_CLS_NAN,FP_CLS_NORMAL):			     \
   case _FP_CLS_COMBINE(FP_CLS_NAN,FP_CLS_INF):				     \
   case _FP_CLS_COMBINE(FP_CLS_NAN,FP_CLS_ZERO):				     \
@@ -319,7 +319,7 @@ do {									     \
 									     \
   case _FP_CLS_COMBINE(FP_CLS_ZERO,FP_CLS_NORMAL):			     \
     R##_e = Y##_e;							     \
-	  /* Fall through */						     \
+	fallthrough;							     \
   case _FP_CLS_COMBINE(FP_CLS_NORMAL,FP_CLS_NAN):			     \
   case _FP_CLS_COMBINE(FP_CLS_INF,FP_CLS_NAN):				     \
   case _FP_CLS_COMBINE(FP_CLS_ZERO,FP_CLS_NAN):				     \
@@ -417,7 +417,7 @@ do {							\
   case _FP_CLS_COMBINE(FP_CLS_NAN,FP_CLS_INF):		\
   case _FP_CLS_COMBINE(FP_CLS_NAN,FP_CLS_ZERO):		\
     R##_s = X##_s;					\
-	/* Fall through */				\
+	  fallthrough;					\
 							\
   case _FP_CLS_COMBINE(FP_CLS_INF,FP_CLS_INF):		\
   case _FP_CLS_COMBINE(FP_CLS_INF,FP_CLS_NORMAL):	\
@@ -431,7 +431,7 @@ do {							\
   case _FP_CLS_COMBINE(FP_CLS_INF,FP_CLS_NAN):		\
   case _FP_CLS_COMBINE(FP_CLS_ZERO,FP_CLS_NAN):		\
     R##_s = Y##_s;					\
-	/* Fall through */				\
+	  fallthrough;					\
 							\
   case _FP_CLS_COMBINE(FP_CLS_NORMAL,FP_CLS_INF):	\
   case _FP_CLS_COMBINE(FP_CLS_NORMAL,FP_CLS_ZERO):	\
@@ -497,7 +497,7 @@ do {							\
 							\
   case _FP_CLS_COMBINE(FP_CLS_NORMAL,FP_CLS_ZERO):	\
     FP_SET_EXCEPTION(FP_EX_DIVZERO);			\
-	  /* Fall through */				\
+	fallthrough;					\
   case _FP_CLS_COMBINE(FP_CLS_INF,FP_CLS_ZERO):		\
   case _FP_CLS_COMBINE(FP_CLS_INF,FP_CLS_NORMAL):	\
     R##_c = FP_CLS_INF;					\