The branch main has been updated by tuexen: URL: https://cgit.FreeBSD.org/src/commit/?id=04c2642406815729781e7eb219a5438583fff27f
commit 04c2642406815729781e7eb219a5438583fff27f Author: Peter Lei <[email protected]> AuthorDate: 2025-10-24 19:42:28 +0000 Commit: Michael Tuexen <[email protected]> CommitDate: 2025-10-24 19:45:51 +0000 tcp rack: cleanup The TCP_SAD_DETECTION code was removed. Remove the remaining sysctl-variables and counters. Reviewed by: tuexen MFC after: 3 days Sponsored by: Netflix, Inc. --- sys/netinet/tcp_stacks/rack.c | 201 +------------------------------------- sys/netinet/tcp_stacks/tcp_rack.h | 1 - 2 files changed, 4 insertions(+), 198 deletions(-) diff --git a/sys/netinet/tcp_stacks/rack.c b/sys/netinet/tcp_stacks/rack.c index 50077abdfd86..9ed26d5a617b 100644 --- a/sys/netinet/tcp_stacks/rack.c +++ b/sys/netinet/tcp_stacks/rack.c @@ -204,10 +204,6 @@ static int32_t rack_dnd_default = 0; /* For rr_conf = 3, what is the default fo static int32_t rack_rxt_controls = 0; static int32_t rack_fill_cw_state = 0; static uint8_t rack_req_measurements = 1; -/* Attack threshold detections */ -static uint32_t rack_highest_sack_thresh_seen = 0; -static uint32_t rack_highest_move_thresh_seen = 0; -static uint32_t rack_merge_out_sacks_on_attack = 0; static int32_t rack_enable_hw_pacing = 0; /* Due to CCSP keep it off by default */ static int32_t rack_hw_rate_caps = 0; /* 1; */ static int32_t rack_hw_rate_cap_per = 0; /* 0 -- off */ @@ -223,7 +219,6 @@ static int32_t rack_default_pacing_divisor = 250; static uint16_t rack_pacing_min_seg = 0; static int32_t rack_timely_off = 0; -static uint32_t sad_seg_size_per = 800; /* 80.0 % */ static int32_t rack_pkt_delay = 1000; static int32_t rack_send_a_lot_in_prr = 1; static int32_t rack_min_to = 1000; /* Number of microsecond min timeout */ @@ -399,18 +394,6 @@ counter_u64_t rack_extended_rfo; counter_u64_t rack_sack_proc_all; counter_u64_t rack_sack_proc_short; counter_u64_t rack_sack_proc_restart; -counter_u64_t rack_sack_attacks_detected; -counter_u64_t rack_sack_attacks_reversed; -counter_u64_t rack_sack_attacks_suspect; -counter_u64_t rack_sack_used_next_merge; -counter_u64_t rack_sack_splits; -counter_u64_t rack_sack_used_prev_merge; -counter_u64_t rack_sack_skipped_acked; -counter_u64_t rack_ack_total; -counter_u64_t rack_express_sack; -counter_u64_t rack_sack_total; -counter_u64_t rack_move_none; -counter_u64_t rack_move_some; counter_u64_t rack_input_idle_reduces; counter_u64_t rack_collapsed_win; @@ -834,18 +817,6 @@ sysctl_rack_clear(SYSCTL_HANDLER_ARGS) counter_u64_zero(rack_rxt_clamps_cwnd_uniq); counter_u64_zero(rack_multi_single_eq); counter_u64_zero(rack_proc_non_comp_ack); - counter_u64_zero(rack_sack_attacks_detected); - counter_u64_zero(rack_sack_attacks_reversed); - counter_u64_zero(rack_sack_attacks_suspect); - counter_u64_zero(rack_sack_used_next_merge); - counter_u64_zero(rack_sack_used_prev_merge); - counter_u64_zero(rack_sack_splits); - counter_u64_zero(rack_sack_skipped_acked); - counter_u64_zero(rack_ack_total); - counter_u64_zero(rack_express_sack); - counter_u64_zero(rack_sack_total); - counter_u64_zero(rack_move_none); - counter_u64_zero(rack_move_some); counter_u64_zero(rack_try_scwnd); counter_u64_zero(rack_collapsed_win); counter_u64_zero(rack_collapsed_win_rxt); @@ -872,7 +843,6 @@ static void rack_init_sysctls(void) { struct sysctl_oid *rack_counters; - struct sysctl_oid *rack_attack; struct sysctl_oid *rack_pacing; struct sysctl_oid *rack_timely; struct sysctl_oid *rack_timers; @@ -883,12 +853,6 @@ rack_init_sysctls(void) struct sysctl_oid *rack_probertt; struct sysctl_oid *rack_hw_pacing; - rack_attack = SYSCTL_ADD_NODE(&rack_sysctl_ctx, - SYSCTL_CHILDREN(rack_sysctl_root), - OID_AUTO, - "sack_attack", - CTLFLAG_RW | CTLFLAG_MPSAFE, 0, - "Rack Sack Attack Counters and Controls"); rack_counters = SYSCTL_ADD_NODE(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_sysctl_root), OID_AUTO, @@ -1533,11 +1497,6 @@ rack_init_sysctls(void) OID_AUTO, "dnd", CTLFLAG_RW, &rack_dnd_default, 0, "Do not disturb default for rack_rrr = 3"); - SYSCTL_ADD_S32(&rack_sysctl_ctx, - SYSCTL_CHILDREN(rack_misc), - OID_AUTO, "sad_seg_per", CTLFLAG_RW, - &sad_seg_size_per, 800, - "Percentage of segment size needed in a sack 800 = 80.0?"); SYSCTL_ADD_S32(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_misc), OID_AUTO, "rxt_controls", CTLFLAG_RW, @@ -1619,85 +1578,6 @@ rack_init_sysctls(void) &rack_autosndbuf_inc, 20, "What percentage should rack scale up its snd buffer by?"); - - /* Sack Attacker detection stuff */ - SYSCTL_ADD_U32(&rack_sysctl_ctx, - SYSCTL_CHILDREN(rack_attack), - OID_AUTO, "merge_out", CTLFLAG_RW, - &rack_merge_out_sacks_on_attack, 0, - "Do we merge the sendmap when we decide we are being attacked?"); - - SYSCTL_ADD_U32(&rack_sysctl_ctx, - SYSCTL_CHILDREN(rack_attack), - OID_AUTO, "detect_highsackratio", CTLFLAG_RW, - &rack_highest_sack_thresh_seen, 0, - "Highest sack to ack ratio seen"); - SYSCTL_ADD_U32(&rack_sysctl_ctx, - SYSCTL_CHILDREN(rack_attack), - OID_AUTO, "detect_highmoveratio", CTLFLAG_RW, - &rack_highest_move_thresh_seen, 0, - "Highest move to non-move ratio seen"); - rack_ack_total = counter_u64_alloc(M_WAITOK); - SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, - SYSCTL_CHILDREN(rack_attack), - OID_AUTO, "acktotal", CTLFLAG_RD, - &rack_ack_total, - "Total number of Ack's"); - rack_express_sack = counter_u64_alloc(M_WAITOK); - SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, - SYSCTL_CHILDREN(rack_attack), - OID_AUTO, "exp_sacktotal", CTLFLAG_RD, - &rack_express_sack, - "Total expresss number of Sack's"); - rack_sack_total = counter_u64_alloc(M_WAITOK); - SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, - SYSCTL_CHILDREN(rack_attack), - OID_AUTO, "sacktotal", CTLFLAG_RD, - &rack_sack_total, - "Total number of SACKs"); - rack_move_none = counter_u64_alloc(M_WAITOK); - SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, - SYSCTL_CHILDREN(rack_attack), - OID_AUTO, "move_none", CTLFLAG_RD, - &rack_move_none, - "Total number of SACK index reuse of positions under threshold"); - rack_move_some = counter_u64_alloc(M_WAITOK); - SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, - SYSCTL_CHILDREN(rack_attack), - OID_AUTO, "move_some", CTLFLAG_RD, - &rack_move_some, - "Total number of SACK index reuse of positions over threshold"); - rack_sack_attacks_detected = counter_u64_alloc(M_WAITOK); - SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, - SYSCTL_CHILDREN(rack_attack), - OID_AUTO, "attacks", CTLFLAG_RD, - &rack_sack_attacks_detected, - "Total number of SACK attackers that had sack disabled"); - rack_sack_attacks_reversed = counter_u64_alloc(M_WAITOK); - SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, - SYSCTL_CHILDREN(rack_attack), - OID_AUTO, "reversed", CTLFLAG_RD, - &rack_sack_attacks_reversed, - "Total number of SACK attackers that were later determined false positive"); - rack_sack_attacks_suspect = counter_u64_alloc(M_WAITOK); - SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, - SYSCTL_CHILDREN(rack_attack), - OID_AUTO, "suspect", CTLFLAG_RD, - &rack_sack_attacks_suspect, - "Total number of SACKs that triggered early detection"); - - rack_sack_used_next_merge = counter_u64_alloc(M_WAITOK); - SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, - SYSCTL_CHILDREN(rack_attack), - OID_AUTO, "nextmerge", CTLFLAG_RD, - &rack_sack_used_next_merge, - "Total number of times we used the next merge"); - rack_sack_used_prev_merge = counter_u64_alloc(M_WAITOK); - SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, - SYSCTL_CHILDREN(rack_attack), - OID_AUTO, "prevmerge", CTLFLAG_RD, - &rack_sack_used_prev_merge, - "Total number of times we used the prev merge"); /* Counters */ rack_total_bytes = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, @@ -1908,18 +1788,6 @@ rack_init_sysctls(void) OID_AUTO, "sack_short", CTLFLAG_RD, &rack_sack_proc_short, "Total times we took shortcut for sack processing"); - rack_sack_skipped_acked = counter_u64_alloc(M_WAITOK); - SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, - SYSCTL_CHILDREN(rack_attack), - OID_AUTO, "skipacked", CTLFLAG_RD, - &rack_sack_skipped_acked, - "Total number of times we skipped previously sacked"); - rack_sack_splits = counter_u64_alloc(M_WAITOK); - SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, - SYSCTL_CHILDREN(rack_attack), - OID_AUTO, "ofsplit", CTLFLAG_RD, - &rack_sack_splits, - "Total number of times we did the old fashion tree split"); rack_input_idle_reduces = counter_u64_alloc(M_WAITOK); SYSCTL_ADD_COUNTER_U64(&rack_sysctl_ctx, SYSCTL_CHILDREN(rack_counters), @@ -3319,16 +3187,6 @@ rack_counter_destroy(void) counter_u64_free(rack_hw_pace_lost); counter_u64_free(rack_non_fto_send); counter_u64_free(rack_extended_rfo); - counter_u64_free(rack_ack_total); - counter_u64_free(rack_express_sack); - counter_u64_free(rack_sack_total); - counter_u64_free(rack_move_none); - counter_u64_free(rack_move_some); - counter_u64_free(rack_sack_attacks_detected); - counter_u64_free(rack_sack_attacks_reversed); - counter_u64_free(rack_sack_attacks_suspect); - counter_u64_free(rack_sack_used_next_merge); - counter_u64_free(rack_sack_used_prev_merge); counter_u64_free(rack_tlp_tot); counter_u64_free(rack_tlp_newdata); counter_u64_free(rack_tlp_retran); @@ -3351,8 +3209,6 @@ rack_counter_destroy(void) counter_u64_free(rack_sack_proc_all); counter_u64_free(rack_sack_proc_restart); counter_u64_free(rack_sack_proc_short); - counter_u64_free(rack_sack_skipped_acked); - counter_u64_free(rack_sack_splits); counter_u64_free(rack_input_idle_reduces); counter_u64_free(rack_collapsed_win); counter_u64_free(rack_collapsed_win_rxt); @@ -9542,7 +9398,6 @@ do_rest_ofb: goto out; } rack_log_map_chg(tp, rack, &stack_map, rsm, next, MAP_SACK_M1, end, __LINE__); - counter_u64_add(rack_sack_used_next_merge, 1); /* Postion for the next block */ start = next->r_end; rsm = tqhash_next(rack->r_ctl.tqh, next); @@ -9574,7 +9429,6 @@ do_rest_ofb: */ goto out; } - counter_u64_add(rack_sack_splits, 1); rack_clone_rsm(rack, nrsm, rsm, start); rsm->r_just_ret = 0; #ifndef INVARIANTS @@ -9596,7 +9450,6 @@ do_rest_ofb: } } else { /* Already sacked this piece */ - counter_u64_add(rack_sack_skipped_acked, 1); if (end == rsm->r_end) { /* Done with block */ rsm = tqhash_next(rack->r_ctl.tqh, rsm); @@ -9696,8 +9549,6 @@ do_rest_ofb: rsm->r_in_tmap = 0; } rack_log_map_chg(tp, rack, NULL, rsm, NULL, MAP_SACK_M3, end, __LINE__); - } else { - counter_u64_add(rack_sack_skipped_acked, 1); } if (end == rsm->r_end) { /* This block only - done, setup for next */ @@ -9876,7 +9727,6 @@ do_rest_ofb: } rack_log_map_chg(tp, rack, prev, &stack_map, rsm, MAP_SACK_M4, end, __LINE__); rsm = prev; - counter_u64_add(rack_sack_used_prev_merge, 1); } else { /** * This is the case where our previous @@ -9941,7 +9791,6 @@ do_rest_ofb: * rsm |---| (acked) * nrsm |------| (not acked) */ - counter_u64_add(rack_sack_splits, 1); rack_clone_rsm(rack, nrsm, rsm, end); rsm->r_flags &= (~RACK_HAS_FIN); rsm->r_just_ret = 0; @@ -9989,11 +9838,6 @@ do_rest_ofb: rsm->r_in_tmap = 0; } } - } else if (start != end){ - /* - * The block was already acked. - */ - counter_u64_add(rack_sack_skipped_acked, 1); } out: if (rsm && @@ -10786,17 +10630,6 @@ rack_log_ack(struct tcpcb *tp, struct tcpopt *to, struct tcphdr *th, int entered changed = 0; th_ack = th->th_ack; segsiz = ctf_fixed_maxseg(rack->rc_tp); - if (BYTES_THIS_ACK(tp, th) >= segsiz) { - /* - * You only get credit for - * MSS and greater (and you get extra - * credit for larger cum-ack moves). - */ - int ac; - - ac = BYTES_THIS_ACK(tp, th) / ctf_fixed_maxseg(rack->rc_tp); - counter_u64_add(rack_ack_total, ac); - } if (SEQ_GT(th_ack, tp->snd_una)) { rack_log_progress_event(rack, tp, ticks, PROGRESS_UPDATE, __LINE__); tp->t_acktime = ticks; @@ -10868,8 +10701,8 @@ rack_log_ack(struct tcpcb *tp, struct tcpopt *to, struct tcphdr *th, int entered if (sacks_seen != NULL) *sacks_seen = num_sack_blks; if (num_sack_blks == 0) { - /* Nothing to sack, but we need to update counts */ - goto out_with_totals; + /* Nothing to sack */ + goto out; } /* Its a sack of some sort */ if (num_sack_blks < 2) { @@ -10892,7 +10725,7 @@ rack_log_ack(struct tcpcb *tp, struct tcpopt *to, struct tcphdr *th, int entered */ again: if (num_sack_blks == 0) - goto out_with_totals; + goto out; if (num_sack_blks > 1) { for (i = 0; i < num_sack_blks; i++) { for (j = i + 1; j < num_sack_blks; j++) { @@ -10945,19 +10778,7 @@ do_sack_work: changed += acked; } if (num_sack_blks == 1) { - /* - * This is what we would expect from - * a normal implementation to happen - * after we have retransmitted the FR, - * i.e the sack-filter pushes down - * to 1 block and the next to be retransmitted - * is the sequence in the sack block (has more - * are acked). Count this as ACK'd data to boost - * up the chances of recovering any false positives. - */ - counter_u64_add(rack_ack_total, (acked / ctf_fixed_maxseg(rack->rc_tp))); - counter_u64_add(rack_express_sack, 1); - goto out_with_totals; + goto out; } else { /* * Start the loop through the @@ -10966,7 +10787,6 @@ do_sack_work: loop_start = 1; } } - counter_u64_add(rack_sack_total, 1); rsm = rack->r_ctl.rc_sacklast; for (i = loop_start; i < num_sack_blks; i++) { acked = rack_proc_sack_blk(tp, rack, &sack_blocks[i], to, &rsm, cts, segsiz); @@ -10975,18 +10795,6 @@ do_sack_work: changed += acked; } } -out_with_totals: - if (num_sack_blks > 1) { - /* - * You get an extra stroke if - * you have more than one sack-blk, this - * could be where we are skipping forward - * and the sack-filter is still working, or - * it could be an attacker constantly - * moving us. - */ - counter_u64_add(rack_move_some, 1); - } out: if (changed) { /* Something changed cancel the rack timer */ @@ -14706,7 +14514,6 @@ rack_init(struct tcpcb *tp, void **ptr) rack->r_ctl.rc_prr_sendalot = rack_send_a_lot_in_prr; rack->r_ctl.rc_min_to = rack_min_to; microuptime(&rack->r_ctl.act_rcv_time); - rack->r_ctl.rc_last_time_decay = rack->r_ctl.act_rcv_time; rack->r_ctl.rack_per_of_gp_ss = rack_per_of_gp_ss; if (rack_hw_up_only) rack->r_up_only = 1; diff --git a/sys/netinet/tcp_stacks/tcp_rack.h b/sys/netinet/tcp_stacks/tcp_rack.h index 144b4fabf7eb..cac17d9aeb50 100644 --- a/sys/netinet/tcp_stacks/tcp_rack.h +++ b/sys/netinet/tcp_stacks/tcp_rack.h @@ -462,7 +462,6 @@ struct rack_control { uint64_t rc_gp_output_ts; /* chg*/ uint64_t rc_gp_cumack_ts; /* chg*/ struct timeval act_rcv_time; - struct timeval rc_last_time_decay; /* SAD time decay happened here */ uint64_t gp_bw; uint64_t init_rate; #ifdef NETFLIX_SHARED_CWND
