Merge branch 'refactor-duplicate-codes-in-the-tc-cls-walk-function'

Zhengchao Shao says:

====================
refactor duplicate codes in the tc cls walk function

The walk implementation of most tc cls modules is basically the same.
That is, the values of count and skip are checked first. If count is
greater than or equal to skip, the registered fn function is executed.
Otherwise, increase the value of count. So the code can be refactored.
Then use helper function to replace the code of each cls module in
alphabetical order.

The walk function is invoked during dump. Therefore, test cases related
 to the tdc filter need to be added.
====================

Link: https://lore.kernel.org/r/20220916020251.190097-1-shaozhengchao@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

8 files changed, 15 insertions, 75 deletions

diff --git a/net/sched/cls_basic.c b/net/sched/cls_basic.c
index 8158fc9ee1ab..d9fbaa0fbe8b 100644
--- a/net/sched/cls_basic.c
+++ b/net/sched/cls_basic.c
@@ -251,15 +251,8 @@ static void basic_walk(struct tcf_proto *tp, struct tcf_walker *arg,
 	struct basic_filter *f;
 
 	list_for_each_entry(f, &head->flist, link) {
-		if (arg->count < arg->skip)
-			goto skip;
-
-		if (arg->fn(tp, f, arg) < 0) {
-			arg->stop = 1;
+		if (!tc_cls_stats_dump(tp, arg, f))
 			break;
-		}
-skip:
-		arg->count++;
 	}
 }
 
diff --git a/net/sched/cls_bpf.c b/net/sched/cls_bpf.c
index c85b85a192bf..938be14cfa3f 100644
--- a/net/sched/cls_bpf.c
+++ b/net/sched/cls_bpf.c
@@ -650,14 +650,8 @@ static void cls_bpf_walk(struct tcf_proto *tp, struct tcf_walker *arg,
 	struct cls_bpf_prog *prog;
 
 	list_for_each_entry(prog, &head->plist, link) {
-		if (arg->count < arg->skip)
-			goto skip;
-		if (arg->fn(tp, prog, arg) < 0) {
-			arg->stop = 1;
+		if (!tc_cls_stats_dump(tp, arg, prog))
 			break;
-		}
-skip:
-		arg->count++;
 	}
 }
 
diff --git a/net/sched/cls_flow.c b/net/sched/cls_flow.c
index 972303aa8edd..014cd3de7b5d 100644
--- a/net/sched/cls_flow.c
+++ b/net/sched/cls_flow.c
@@ -683,14 +683,8 @@ static void flow_walk(struct tcf_proto *tp, struct tcf_walker *arg,
 	struct flow_filter *f;
 
 	list_for_each_entry(f, &head->filters, list) {
-		if (arg->count < arg->skip)
-			goto skip;
-		if (arg->fn(tp, f, arg) < 0) {
-			arg->stop = 1;
+		if (!tc_cls_stats_dump(tp, arg, f))
 			break;
-		}
-skip:
-		arg->count++;
 	}
 }
 
diff --git a/net/sched/cls_fw.c b/net/sched/cls_fw.c
index 8654b0ce997c..fa66191574a4 100644
--- a/net/sched/cls_fw.c
+++ b/net/sched/cls_fw.c
@@ -358,15 +358,8 @@ static void fw_walk(struct tcf_proto *tp, struct tcf_walker *arg,
 
 		for (f = rtnl_dereference(head->ht[h]); f;
 		     f = rtnl_dereference(f->next)) {
-			if (arg->count < arg->skip) {
-				arg->count++;
-				continue;
-			}
-			if (arg->fn(tp, f, arg) < 0) {
-				arg->stop = 1;
+			if (!tc_cls_stats_dump(tp, arg, f))
 				return;
-			}
-			arg->count++;
 		}
 	}
 }
diff --git a/net/sched/cls_route.c b/net/sched/cls_route.c
index 29adac7812fe..17bb04af2fa8 100644
--- a/net/sched/cls_route.c
+++ b/net/sched/cls_route.c
@@ -587,15 +587,8 @@ static void route4_walk(struct tcf_proto *tp, struct tcf_walker *arg,
 				for (f = rtnl_dereference(b->ht[h1]);
 				     f;
 				     f = rtnl_dereference(f->next)) {
-					if (arg->count < arg->skip) {
-						arg->count++;
-						continue;
-					}
-					if (arg->fn(tp, f, arg) < 0) {
-						arg->stop = 1;
+					if (!tc_cls_stats_dump(tp, arg, f))
 						return;
-					}
-					arg->count++;
 				}
 			}
 		}
diff --git a/net/sched/cls_rsvp.h b/net/sched/cls_rsvp.h
index 5cd9d6b143c4..fb60f2c2c325 100644
--- a/net/sched/cls_rsvp.h
+++ b/net/sched/cls_rsvp.h
@@ -671,15 +671,8 @@ static void rsvp_walk(struct tcf_proto *tp, struct tcf_walker *arg,
 
 				for (f = rtnl_dereference(s->ht[h1]); f;
 				     f = rtnl_dereference(f->next)) {
-					if (arg->count < arg->skip) {
-						arg->count++;
-						continue;
-					}
-					if (arg->fn(tp, f, arg) < 0) {
-						arg->stop = 1;
+					if (!tc_cls_stats_dump(tp, arg, f))
 						return;
-					}
-					arg->count++;
 				}
 			}
 		}
diff --git a/net/sched/cls_tcindex.c b/net/sched/cls_tcindex.c
index 742c7d49a958..a33076033462 100644
--- a/net/sched/cls_tcindex.c
+++ b/net/sched/cls_tcindex.c
@@ -566,13 +566,8 @@ static void tcindex_walk(struct tcf_proto *tp, struct tcf_walker *walker,
 		for (i = 0; i < p->hash; i++) {
 			if (!p->perfect[i].res.class)
 				continue;
-			if (walker->count >= walker->skip) {
-				if (walker->fn(tp, p->perfect + i, walker) < 0) {
-					walker->stop = 1;
-					return;
-				}
-			}
-			walker->count++;
+			if (!tc_cls_stats_dump(tp, walker, p->perfect + i))
+				return;
 		}
 	}
 	if (!p->h)
@@ -580,13 +575,8 @@ static void tcindex_walk(struct tcf_proto *tp, struct tcf_walker *walker,
 	for (i = 0; i < p->hash; i++) {
 		for (f = rtnl_dereference(p->h[i]); f; f = next) {
 			next = rtnl_dereference(f->next);
-			if (walker->count >= walker->skip) {
-				if (walker->fn(tp, &f->result, walker) < 0) {
-					walker->stop = 1;
-					return;
-				}
-			}
-			walker->count++;
+			if (!tc_cls_stats_dump(tp, walker, &f->result))
+				return;
 		}
 	}
 }
diff --git a/net/sched/cls_u32.c b/net/sched/cls_u32.c
index 4d27300c287c..58c7680faabd 100644
--- a/net/sched/cls_u32.c
+++ b/net/sched/cls_u32.c
@@ -1125,26 +1125,16 @@ static void u32_walk(struct tcf_proto *tp, struct tcf_walker *arg,
 	     ht = rtnl_dereference(ht->next)) {
 		if (ht->prio != tp->prio)
 			continue;
-		if (arg->count >= arg->skip) {
-			if (arg->fn(tp, ht, arg) < 0) {
-				arg->stop = 1;
-				return;
-			}
-		}
-		arg->count++;
+
+		if (!tc_cls_stats_dump(tp, arg, ht))
+			return;
+
 		for (h = 0; h <= ht->divisor; h++) {
 			for (n = rtnl_dereference(ht->ht[h]);
 			     n;
 			     n = rtnl_dereference(n->next)) {
-				if (arg->count < arg->skip) {
-					arg->count++;
-					continue;
-				}
-				if (arg->fn(tp, n, arg) < 0) {
-					arg->stop = 1;
+				if (!tc_cls_stats_dump(tp, arg, n))
 					return;
-				}
-				arg->count++;
 			}
 		}
 	}