[PATCH bpf 2/8] selftests/bpf: Fix SENDPAGE data logic in test_sockmap

[zijianzhang@xxxxxxxxxxxxx]

From: Zijian Zhang <zijianzhang@xxxxxxxxxxxxx>

In the SENDPAGE test, "opt->iov_length * cnt" size of data will be sent
in cnt times of sendfile.
1. In push/pop tests, they will be invoked cnt times, for the simplicity of
msg_verify_data, change chunk_sz to iov_length
2. Change iov_length in test_send_large from 1024 to 8192. We have pop test
where txmsg_start_pop is 4096. 4096 > 1024, an error will be returned.

Fixes: 328aa08a081b ("bpf: Selftests, break down test_sockmap into subtests")
Signed-off-by: Zijian Zhang <zijianzhang@xxxxxxxxxxxxx>
---
 tools/testing/selftests/bpf/test_sockmap.c | 18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/tools/testing/selftests/bpf/test_sockmap.c b/tools/testing/selftests/bpf/test_sockmap.c
index 0f065273fde3..1d59bed90d80 100644
--- a/tools/testing/selftests/bpf/test_sockmap.c
+++ b/tools/testing/selftests/bpf/test_sockmap.c
@@ -420,16 +420,18 @@ static int msg_loop_sendpage(int fd, int iov_length, int cnt,
 {
 	bool drop = opt->drop_expected;
 	unsigned char k = 0;
+	int i, j, fp;
 	FILE *file;
-	int i, fp;
 
 	file = tmpfile();
 	if (!file) {
 		perror("create file for sendpage");
 		return 1;
 	}
-	for (i = 0; i < iov_length * cnt; i++, k++)
-		fwrite(&k, sizeof(char), 1, file);
+	for (i = 0; i < cnt; i++, k = 0) {
+		for (j = 0; j < iov_length; j++, k++)
+			fwrite(&k, sizeof(char), 1, file);
+	}
 	fflush(file);
 	fseek(file, 0, SEEK_SET);
 
@@ -623,7 +625,9 @@ static int msg_loop(int fd, int iov_count, int iov_length, int cnt,
 		 * This is really only useful for testing edge cases in code
 		 * paths.
 		 */
-		total_bytes = (float)iov_count * (float)iov_length * (float)cnt;
+		total_bytes = (float)iov_length * (float)cnt;
+		if (!opt->sendpage)
+			total_bytes *= (float)iov_count;
 		if (txmsg_apply)
 			txmsg_pop_total = txmsg_pop * (total_bytes / txmsg_apply);
 		else
@@ -701,7 +705,7 @@ static int msg_loop(int fd, int iov_count, int iov_length, int cnt,
 
 			if (data) {
 				int chunk_sz = opt->sendpage ?
-						iov_length * cnt :
+						iov_length :
 						iov_length * iov_count;
 
 				errno = msg_verify_data(&msg, recv, chunk_sz, &k, &bytes_cnt);
@@ -1466,8 +1470,8 @@ static void test_send_many(struct sockmap_options *opt, int cgrp)
 
 static void test_send_large(struct sockmap_options *opt, int cgrp)
 {
-	opt->iov_length = 256;
-	opt->iov_count = 1024;
+	opt->iov_length = 8192;
+	opt->iov_count = 32;
 	opt->rate = 2;
 	test_exec(cgrp, opt);
 }
-- 
2.20.1