Date: Mon, 20 Apr 2026 11:56:18 +0200 From: Michael Tuexen <tuexen@FreeBSD.org> To: =?utf-8?Q?Roger_Pau_Monn=C3=A9?= <royger@freebsd.org> Cc: Andrew Gallatin <gallatin@freebsd.org>, src-committers@freebsd.org, dev-commits-src-all@freebsd.org, dev-commits-src-main@freebsd.org Subject: Re: git: 3fade68cfdf9 - main - iflib: accurately count bytes/segments for TSO Message-ID: <B7C70056-8917-4ED6-BDCA-001F78A37FFB@FreeBSD.org> In-Reply-To: <aeXjUNlDR029ijWB@macbook.local> References: <69e26f4a.346e1.31c510c2@gitrepo.freebsd.org> <aeXjUNlDR029ijWB@macbook.local>
index | next in thread | previous in thread | raw e-mail
> On 20. Apr 2026, at 10:26, Roger Pau Monné <royger@freebsd.org> wrote: > > On Fri, Apr 17, 2026 at 05:35:06PM +0000, Andrew Gallatin wrote: >> The branch main has been updated by gallatin: >> >> URL: https://cgit.FreeBSD.org/src/commit/?id=3fade68cfdf95ee0b517b5d69b270bd8da633404 >> >> commit 3fade68cfdf95ee0b517b5d69b270bd8da633404 >> Author: Andrew Gallatin <gallatin@FreeBSD.org> >> AuthorDate: 2026-04-17 15:45:22 +0000 >> Commit: Andrew Gallatin <gallatin@FreeBSD.org> >> CommitDate: 2026-04-17 17:34:27 +0000 >> >> iflib: accurately count bytes/segments for TSO >> >> When using software based ifnet counters, iflib has not factored >> TSO into account when reporting the segments and bytes sent. >> So it will underreport NIC bandwidth by a small percent, >> and will undercount sent segments by a large factor. >> Fix this by calculating the number of added segments the NIC >> will send, and add header size multiplied by that number >> to arrive at a correct accounting of segments and bytes sent. >> This makes these software counters directly comparable to >> hardware counters. >> >> Doing this requires moving the calculation into iflib_encap() where >> we have already parsed the packet and know the header size, MSS, etc. > > Hello, > > This causes a reliable crash on my box when I attempt to ssh into it: > > panic: Assertion mp != NULL && *mp != NULL failed at /usr/src/sys/net/iflib.c:3922 > cpuid = 11 > time = 1776673321 > KDB: stack backtrace: > db_trace_self_wrapper() at db_trace_self_wrapper+0x2b/frame 0xfffffe0115bbf3e0 > vpanic() at vpanic+0x136/frame 0xfffffe0115bbf510 > panic() at panic+0x43/frame 0xfffffe0115bbf570 > iflib_txq_drain() at iflib_txq_drain+0x429/frame 0xfffffe0115bbf5f0 > drain_ring_lockless() at drain_ring_lockless+0x8a/frame 0xfffffe0115bbf640 > ifmp_ring_enqueue() at ifmp_ring_enqueue+0x332/frame 0xfffffe0115bbf690 > iflib_if_transmit() at iflib_if_transmit+0x273/frame 0xfffffe0115bbf710 > bridge_enqueue() at bridge_enqueue+0x214/frame 0xfffffe0115bbf760 > bridge_output() at bridge_output+0x10a/frame 0xfffffe0115bbf7b0 > ether_output() at ether_output+0x689/frame 0xfffffe0115bbf840 > ip_output() at ip_output+0x183d/frame 0xfffffe0115bbf960 > tcp_default_output() at tcp_default_output+0x21d8/frame 0xfffffe0115bbfb30 > tcp_usr_send() at tcp_usr_send+0x5d0/frame 0xfffffe0115bbfbe0 > sosend_generic_locked() at sosend_generic_locked+0x59b/frame 0xfffffe0115bbfc90 > sosend_generic() at sosend_generic+0x61/frame 0xfffffe0115bbfce0 > sousrsend() at sousrsend+0x79/frame 0xfffffe0115bbfd40 > dofilewrite() at dofilewrite+0x81/frame 0xfffffe0115bbfd90 > sys_write() at sys_write+0x127/frame 0xfffffe0115bbfe00 > amd64_syscall() at amd64_syscall+0x169/frame 0xfffffe0115bbff30 > fast_syscall_common() at fast_syscall_common+0xf8/frame 0xfffffe0115bbff30 > --- syscall (4, FreeBSD ELF64, write), rip = 0x297fd795023a, rsp = 0x297fccb77d98, rbp = 0x297fccb77dc0 --- > KDB: enter: panic > [ thread pid 3093 tid 100634 ] > Stopped at kdb_enter+0x33: movq $0,0x15dd302(%rip) > db> > > My network config is: > > ifconfig_igc0="DHCP" > cloned_interfaces="bridge0" > ifconfig_bridge0="addm igc0" Can you check if https://cgit.FreeBSD.org/src/commit/?id=cca22c36c306dfabe13b1d1de10e8d27ef3c3bce <https://cgit.freebsd.org/src/commit/?id=cca22c36c306dfabe13b1d1de10e8d27ef3c3bce>; fixes the issue for you? Best regards Michael > > Thanks, Roger. >home | help
Want to link to this message? Use this
URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?B7C70056-8917-4ED6-BDCA-001F78A37FFB>