Hi Lawrence, Thank you for the patch! Perhaps something to improve:
[auto build test WARNING on net-next/master] url: https://github.com/0day-ci/linux/commits/Lawrence-Brakmo/tcp-force-cwnd-at-least-2-in-tcp_cwnd_reduction/20180627-095533 reproduce: # apt-get install sparse make ARCH=x86_64 allmodconfig make C=1 CF=-D__CHECK_ENDIAN__ sparse warnings: (new ones prefixed by >>) net/ipv4/tcp_input.c:168:42: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:168:42: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:213:21: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:213:21: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:329:19: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:329:19: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:336:19: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:337:19: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:337:19: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:347:33: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:347:33: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:412:32: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:412:32: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:413:44: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:413:44: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:436:33: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:436:33: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:464:44: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:464:44: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:473:36: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:473:36: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:475:28: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:475:28: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:492:33: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:492:33: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:496:36: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:496:36: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:509:29: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:509:29: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:511:16: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:511:16: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:512:16: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:513:16: sparse: expression using sizeof(void) include/net/tcp.h:739:16: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:652:26: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:652:26: sparse: expression using sizeof(void) include/net/tcp.h:739:16: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:790:33: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:790:33: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:794:23: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:818:17: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:818:17: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:827:9: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:827:9: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:867:16: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:867:16: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:902:34: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:902:34: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:1654:25: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:1848:17: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:1849:17: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:1849:17: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:1869:26: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:1869:26: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:1896:34: sparse: expression using sizeof(void) include/net/tcp.h:1138:24: sparse: expression using sizeof(void) include/net/tcp.h:1138:24: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:1995:34: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:1995:34: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:2024:39: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:2024:39: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:2400:44: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:2472:26: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:2472:26: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:2472:26: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:2472:26: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:2472:26: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:2472:26: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:2472:26: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:2472:26: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:2472:26: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:2472:26: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:2472:26: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:2472:26: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:2472:26: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:2472:26: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:2476:26: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:2476:26: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:2479:18: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:2479:18: sparse: expression using sizeof(void) >> net/ipv4/tcp_input.c:2480:24: sparse: incompatible types in comparison >> expression (different signedness) include/net/tcp.h:1138:24: sparse: expression using sizeof(void) include/net/tcp.h:1138:24: sparse: expression using sizeof(void) include/net/tcp.h:1138:24: sparse: expression using sizeof(void) include/net/tcp.h:1138:24: sparse: expression using sizeof(void) include/net/tcp.h:1138:24: sparse: expression using sizeof(void) include/net/tcp.h:1138:24: sparse: expression using sizeof(void) include/net/tcp.h:1138:24: sparse: expression using sizeof(void) include/net/tcp.h:1138:24: sparse: expression using sizeof(void) include/net/tcp.h:739:16: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:2990:48: sparse: expression using sizeof(void) include/net/tcp.h:739:16: sparse: expression using sizeof(void) include/net/tcp.h:739:16: sparse: expression using sizeof(void) include/net/tcp.h:739:16: sparse: expression using sizeof(void) include/net/tcp.h:739:16: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:3195:46: sparse: expression using sizeof(void) net/ipv4/tcp_input.c:3195:46: sparse: expression using sizeof(void) include/net/tcp.h:739:16: sparse: expression using sizeof(void) include/net/tcp.h:1206:16: sparse: expression using sizeof(void) include/net/tcp.h:1215:31: sparse: expression using sizeof(void) include/net/tcp.h:1215:31: sparse: too many warnings In file included from include/asm-generic/bug.h:18:0, from arch/x86/include/asm/bug.h:83, from include/linux/bug.h:5, from include/linux/mmdebug.h:5, from include/linux/mm.h:9, from net/ipv4/tcp_input.c:67: net/ipv4/tcp_input.c: In function 'tcp_cwnd_reduction': include/linux/kernel.h:812:29: warning: comparison of distinct pointer types lacks a cast (!!(sizeof((typeof(x) *)1 == (typeof(y) *)1))) ^ include/linux/kernel.h:826:4: note: in expansion of macro '__typecheck' (__typecheck(x, y) && __no_side_effects(x, y)) ^~~~~~~~~~~ include/linux/kernel.h:836:24: note: in expansion of macro '__safe_cmp' __builtin_choose_expr(__safe_cmp(x, y), 117- ^~~~~~~~~~ include/linux/kernel.h:852:19: note: in expansion of macro '__careful_cmp' #define max(x, y) __careful_cmp(x, y, >) ^~~~~~~~~~~~~ net/ipv4/tcp_input.c:2480:17: note: in expansion of macro 'max' tp->snd_cwnd = max(tcp_packets_in_flight(tp) + sndcnt, 2); ^~~ vim +2480 net/ipv4/tcp_input.c 2455 2456 void tcp_cwnd_reduction(struct sock *sk, int newly_acked_sacked, int flag) 2457 { 2458 struct tcp_sock *tp = tcp_sk(sk); 2459 int sndcnt = 0; 2460 int delta = tp->snd_ssthresh - tcp_packets_in_flight(tp); 2461 2462 if (newly_acked_sacked <= 0 || WARN_ON_ONCE(!tp->prior_cwnd)) 2463 return; 2464 2465 tp->prr_delivered += newly_acked_sacked; 2466 if (delta < 0) { 2467 u64 dividend = (u64)tp->snd_ssthresh * tp->prr_delivered + 2468 tp->prior_cwnd - 1; 2469 sndcnt = div_u64(dividend, tp->prior_cwnd) - tp->prr_out; 2470 } else if ((flag & FLAG_RETRANS_DATA_ACKED) && 2471 !(flag & FLAG_LOST_RETRANS)) { > 2472 sndcnt = min_t(int, delta, 2473 max_t(int, tp->prr_delivered - tp->prr_out, 2474 newly_acked_sacked) + 1); 2475 } else { 2476 sndcnt = min(delta, newly_acked_sacked); 2477 } 2478 /* Force a fast retransmit upon entering fast recovery */ 2479 sndcnt = max(sndcnt, (tp->prr_out ? 0 : 1)); > 2480 tp->snd_cwnd = max(tcp_packets_in_flight(tp) + sndcnt, 2); 2481 } 2482 --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/pipermail/kbuild-all Intel Corporation
