From mboxrd@z Thu Jan 1 00:00:00 1970 From: Willem de Bruijn Subject: [PATCH net-next 7/7] packet: rollover statistics Date: Wed, 6 May 2015 14:27:17 -0400 Message-ID: <1430936837-22655-8-git-send-email-willemb@google.com> References: <1430936837-22655-1-git-send-email-willemb@google.com> Cc: davem@davemloft.net, Willem de Bruijn To: netdev@vger.kernel.org Return-path: Received: from mail-yh0-f49.google.com ([209.85.213.49]:35660 "EHLO mail-yh0-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752741AbbEFS12 (ORCPT ); Wed, 6 May 2015 14:27:28 -0400 Received: by yhda23 with SMTP id a23so4711871yhd.2 for ; Wed, 06 May 2015 11:27:27 -0700 (PDT) In-Reply-To: <1430936837-22655-1-git-send-email-willemb@google.com> Sender: netdev-owner@vger.kernel.org List-ID: From: Willem de Bruijn Rollover indicates exceptional conditions. Export a counter to inform socket owners of this state. If no socket with sufficient room is found, rollover fails. Also count these events. Finally, also count when flows are rolled over early thanks to huge flow detection, to validate its correctness. Tested: Read counters in bench_rollover on all other tests in the patchset Signed-off-by: Willem de Bruijn --- include/uapi/linux/if_packet.h | 7 +++++++ net/packet/af_packet.c | 17 +++++++++++++++++ net/packet/internal.h | 3 +++ 3 files changed, 27 insertions(+) diff --git a/include/uapi/linux/if_packet.h b/include/uapi/linux/if_packet.h index 053bd10..52b6501 100644 --- a/include/uapi/linux/if_packet.h +++ b/include/uapi/linux/if_packet.h @@ -54,6 +54,7 @@ struct sockaddr_ll { #define PACKET_FANOUT 18 #define PACKET_TX_HAS_OFF 19 #define PACKET_QDISC_BYPASS 20 +#define PACKET_ROLLOVER_STATS 21 #define PACKET_FANOUT_HASH 0 #define PACKET_FANOUT_LB 1 @@ -75,6 +76,12 @@ struct tpacket_stats_v3 { unsigned int tp_freeze_q_cnt; }; +struct tpacket_rollover_stats { + unsigned long tp_all; + unsigned long tp_huge; + unsigned long tp_failed; +}; + union tpacket_stats_u { struct tpacket_stats stats1; struct tpacket_stats_v3 stats3; diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index 4e54b6b..9a82196 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -1402,6 +1402,9 @@ static unsigned int fanout_demux_rollover(struct packet_fanout *f, packet_rcv_has_room(po_next, skb) == ROOM_NORMAL) { if (i != j) po->rollover->sock = i; + atomic_long_inc(&po->rollover->num); + if (room == ROOM_LOW) + atomic_long_inc(&po->rollover->num_huge); return i; } @@ -1409,6 +1412,7 @@ static unsigned int fanout_demux_rollover(struct packet_fanout *f, i = 0; } while (i != j); + atomic_long_inc(&po->rollover->num_failed); return idx; } @@ -1544,6 +1548,9 @@ static int fanout_add(struct sock *sk, u16 id, u16 type_flags) if (!po->rollover) return -ENOMEM; spin_lock_init(&po->rollover->hist_lock); + atomic_long_set(&po->rollover->num, 0); + atomic_long_set(&po->rollover->num_huge, 0); + atomic_long_set(&po->rollover->num_failed, 0); } mutex_lock(&fanout_mutex); @@ -3571,6 +3578,7 @@ static int packet_getsockopt(struct socket *sock, int level, int optname, struct packet_sock *po = pkt_sk(sk); void *data = &val; union tpacket_stats_u st; + struct tpacket_rollover_stats rstats; if (level != SOL_PACKET) return -ENOPROTOOPT; @@ -3646,6 +3654,15 @@ static int packet_getsockopt(struct socket *sock, int level, int optname, ((u32)po->fanout->flags << 24)) : 0); break; + case PACKET_ROLLOVER_STATS: + if (!po->rollover) + return -EINVAL; + rstats.tp_all = atomic_long_read(&po->rollover->num); + rstats.tp_huge = atomic_long_read(&po->rollover->num_huge); + rstats.tp_failed = atomic_long_read(&po->rollover->num_failed); + data = &rstats; + lv = sizeof(rstats); + break; case PACKET_TX_HAS_OFF: val = po->tp_tx_has_off; break; diff --git a/net/packet/internal.h b/net/packet/internal.h index 6f479c4..5d51b7b 100644 --- a/net/packet/internal.h +++ b/net/packet/internal.h @@ -89,6 +89,9 @@ struct packet_fanout { struct packet_rollover { int sock; + atomic_long_t num; + atomic_long_t num_huge; + atomic_long_t num_failed; int hist_idx; #define ROLLOVER_HLEN (L1_CACHE_BYTES / sizeof(u32)) u32 history[ROLLOVER_HLEN] ____cacheline_aligned; -- 2.2.0.rc0.207.ga3a616c