* [net-next:main 26/50] net/ipv4/tcp.c:4673:2: error: call to '__compiletime_assert_1030' declared with 'error' attribute: BUILD_BUG_ON failed: offsetof(struct tcp_sock, __cacheline_group_end__tcp_sock_write_txrx) - offsetofend(struct tcp_sock, __cacheline_group_begin__tcp_sock_...
@ 2024-04-08 14:49 kernel test robot
2024-04-08 23:06 ` Vladimir Oltean
0 siblings, 1 reply; 8+ messages in thread
From: kernel test robot @ 2024-04-08 14:49 UTC (permalink / raw)
To: Eric Dumazet; +Cc: llvm, oe-kbuild-all, netdev
tree: https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git main
head: 358961f51fa5fa1aebf9c25fdcf4f9750f3c647e
commit: d2c3a7eb1afada8cfb5fde41489913ea5733a319 [26/50] tcp: more struct tcp_sock adjustments
config: hexagon-allmodconfig (https://download.01.org/0day-ci/archive/20240408/202404082207.HCEdQhUO-lkp@intel.com/config)
compiler: clang version 19.0.0git (https://github.com/llvm/llvm-project 73ddb2a7471986a7ed600dbea14efc60f0d0db47)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240408/202404082207.HCEdQhUO-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202404082207.HCEdQhUO-lkp@intel.com/
All errors (new ones prefixed by >>):
In file included from net/ipv4/tcp.c:252:
In file included from include/linux/inet_diag.h:5:
In file included from include/net/netlink.h:6:
In file included from include/linux/netlink.h:7:
In file included from include/linux/skbuff.h:17:
In file included from include/linux/bvec.h:10:
In file included from include/linux/highmem.h:10:
In file included from include/linux/mm.h:2208:
include/linux/vmstat.h:522:36: warning: arithmetic between different enumeration types ('enum node_stat_item' and 'enum lru_list') [-Wenum-enum-conversion]
522 | return node_stat_name(NR_LRU_BASE + lru) + 3; // skip "nr_"
| ~~~~~~~~~~~ ^ ~~~
In file included from net/ipv4/tcp.c:252:
In file included from include/linux/inet_diag.h:5:
In file included from include/net/netlink.h:6:
In file included from include/linux/netlink.h:7:
In file included from include/linux/skbuff.h:17:
In file included from include/linux/bvec.h:10:
In file included from include/linux/highmem.h:12:
In file included from include/linux/hardirq.h:11:
In file included from ./arch/hexagon/include/generated/asm/hardirq.h:1:
In file included from include/asm-generic/hardirq.h:17:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:13:
In file included from arch/hexagon/include/asm/io.h:328:
include/asm-generic/io.h:547:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
547 | val = __raw_readb(PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:560:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
560 | val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr));
| ~~~~~~~~~~ ^
include/uapi/linux/byteorder/little_endian.h:37:51: note: expanded from macro '__le16_to_cpu'
37 | #define __le16_to_cpu(x) ((__force __u16)(__le16)(x))
| ^
In file included from net/ipv4/tcp.c:252:
In file included from include/linux/inet_diag.h:5:
In file included from include/net/netlink.h:6:
In file included from include/linux/netlink.h:7:
In file included from include/linux/skbuff.h:17:
In file included from include/linux/bvec.h:10:
In file included from include/linux/highmem.h:12:
In file included from include/linux/hardirq.h:11:
In file included from ./arch/hexagon/include/generated/asm/hardirq.h:1:
In file included from include/asm-generic/hardirq.h:17:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:13:
In file included from arch/hexagon/include/asm/io.h:328:
include/asm-generic/io.h:573:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
573 | val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr));
| ~~~~~~~~~~ ^
include/uapi/linux/byteorder/little_endian.h:35:51: note: expanded from macro '__le32_to_cpu'
35 | #define __le32_to_cpu(x) ((__force __u32)(__le32)(x))
| ^
In file included from net/ipv4/tcp.c:252:
In file included from include/linux/inet_diag.h:5:
In file included from include/net/netlink.h:6:
In file included from include/linux/netlink.h:7:
In file included from include/linux/skbuff.h:17:
In file included from include/linux/bvec.h:10:
In file included from include/linux/highmem.h:12:
In file included from include/linux/hardirq.h:11:
In file included from ./arch/hexagon/include/generated/asm/hardirq.h:1:
In file included from include/asm-generic/hardirq.h:17:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:13:
In file included from arch/hexagon/include/asm/io.h:328:
include/asm-generic/io.h:584:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
584 | __raw_writeb(value, PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:594:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
594 | __raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:604:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
604 | __raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
>> net/ipv4/tcp.c:4673:2: error: call to '__compiletime_assert_1030' declared with 'error' attribute: BUILD_BUG_ON failed: offsetof(struct tcp_sock, __cacheline_group_end__tcp_sock_write_txrx) - offsetofend(struct tcp_sock, __cacheline_group_begin__tcp_sock_write_txrx) > 92
4673 | CACHELINE_ASSERT_GROUP_SIZE(struct tcp_sock, tcp_sock_write_txrx, 92);
| ^
include/linux/cache.h:108:2: note: expanded from macro 'CACHELINE_ASSERT_GROUP_SIZE'
108 | BUILD_BUG_ON(offsetof(TYPE, __cacheline_group_end__##GROUP) - \
| ^
include/linux/build_bug.h:50:2: note: expanded from macro 'BUILD_BUG_ON'
50 | BUILD_BUG_ON_MSG(condition, "BUILD_BUG_ON failed: " #condition)
| ^
include/linux/build_bug.h:39:37: note: expanded from macro 'BUILD_BUG_ON_MSG'
39 | #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
| ^
note: (skipping 1 expansions in backtrace; use -fmacro-backtrace-limit=0 to see all)
include/linux/compiler_types.h:448:2: note: expanded from macro '_compiletime_assert'
448 | __compiletime_assert(condition, msg, prefix, suffix)
| ^
include/linux/compiler_types.h:441:4: note: expanded from macro '__compiletime_assert'
441 | prefix ## suffix(); \
| ^
<scratch space>:29:1: note: expanded from here
29 | __compiletime_assert_1030
| ^
7 warnings and 1 error generated.
vim +4673 net/ipv4/tcp.c
4600
4601 static void __init tcp_struct_check(void)
4602 {
4603 /* TX read-mostly hotpath cache lines */
4604 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_read_tx, max_window);
4605 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_read_tx, rcv_ssthresh);
4606 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_read_tx, reordering);
4607 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_read_tx, notsent_lowat);
4608 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_read_tx, gso_segs);
4609 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_read_tx, lost_skb_hint);
4610 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_read_tx, retransmit_skb_hint);
4611 CACHELINE_ASSERT_GROUP_SIZE(struct tcp_sock, tcp_sock_read_tx, 40);
4612
4613 /* TXRX read-mostly hotpath cache lines */
4614 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_read_txrx, tsoffset);
4615 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_read_txrx, snd_wnd);
4616 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_read_txrx, mss_cache);
4617 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_read_txrx, snd_cwnd);
4618 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_read_txrx, prr_out);
4619 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_read_txrx, lost_out);
4620 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_read_txrx, sacked_out);
4621 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_read_txrx, scaling_ratio);
4622 CACHELINE_ASSERT_GROUP_SIZE(struct tcp_sock, tcp_sock_read_txrx, 32);
4623
4624 /* RX read-mostly hotpath cache lines */
4625 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_read_rx, copied_seq);
4626 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_read_rx, rcv_tstamp);
4627 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_read_rx, snd_wl1);
4628 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_read_rx, tlp_high_seq);
4629 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_read_rx, rttvar_us);
4630 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_read_rx, retrans_out);
4631 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_read_rx, advmss);
4632 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_read_rx, urg_data);
4633 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_read_rx, lost);
4634 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_read_rx, rtt_min);
4635 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_read_rx, out_of_order_queue);
4636 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_read_rx, snd_ssthresh);
4637 CACHELINE_ASSERT_GROUP_SIZE(struct tcp_sock, tcp_sock_read_rx, 69);
4638
4639 /* TX read-write hotpath cache lines */
4640 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_tx, segs_out);
4641 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_tx, data_segs_out);
4642 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_tx, bytes_sent);
4643 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_tx, snd_sml);
4644 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_tx, chrono_start);
4645 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_tx, chrono_stat);
4646 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_tx, write_seq);
4647 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_tx, pushed_seq);
4648 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_tx, lsndtime);
4649 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_tx, mdev_us);
4650 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_tx, tcp_wstamp_ns);
4651 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_tx, rtt_seq);
4652 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_tx, tsorted_sent_queue);
4653 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_tx, highest_sack);
4654 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_tx, ecn_flags);
4655 CACHELINE_ASSERT_GROUP_SIZE(struct tcp_sock, tcp_sock_write_tx, 89);
4656
4657 /* TXRX read-write hotpath cache lines */
4658 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_txrx, pred_flags);
4659 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_txrx, tcp_clock_cache);
4660 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_txrx, tcp_mstamp);
4661 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_txrx, rcv_nxt);
4662 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_txrx, snd_nxt);
4663 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_txrx, snd_una);
4664 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_txrx, window_clamp);
4665 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_txrx, srtt_us);
4666 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_txrx, packets_out);
4667 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_txrx, snd_up);
4668 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_txrx, delivered);
4669 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_txrx, delivered_ce);
4670 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_txrx, app_limited);
4671 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_txrx, rcv_wnd);
4672 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_txrx, rx_opt);
> 4673 CACHELINE_ASSERT_GROUP_SIZE(struct tcp_sock, tcp_sock_write_txrx, 92);
4674
4675 /* RX read-write hotpath cache lines */
4676 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_rx, bytes_received);
4677 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_rx, segs_in);
4678 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_rx, data_segs_in);
4679 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_rx, rcv_wup);
4680 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_rx, max_packets_out);
4681 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_rx, cwnd_usage_seq);
4682 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_rx, rate_delivered);
4683 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_rx, rate_interval_us);
4684 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_rx, rcv_rtt_last_tsecr);
4685 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_rx, first_tx_mstamp);
4686 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_rx, delivered_mstamp);
4687 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_rx, bytes_acked);
4688 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_rx, rcv_rtt_est);
4689 CACHELINE_ASSERT_GROUP_MEMBER(struct tcp_sock, tcp_sock_write_rx, rcvq_space);
4690 CACHELINE_ASSERT_GROUP_SIZE(struct tcp_sock, tcp_sock_write_rx, 99);
4691 }
4692
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [net-next:main 26/50] net/ipv4/tcp.c:4673:2: error: call to '__compiletime_assert_1030' declared with 'error' attribute: BUILD_BUG_ON failed: offsetof(struct tcp_sock, __cacheline_group_end__tcp_sock_write_txrx) - offsetofend(struct tcp_sock, __cacheline_group_begin__tcp_sock_...
2024-04-08 14:49 [net-next:main 26/50] net/ipv4/tcp.c:4673:2: error: call to '__compiletime_assert_1030' declared with 'error' attribute: BUILD_BUG_ON failed: offsetof(struct tcp_sock, __cacheline_group_end__tcp_sock_write_txrx) - offsetofend(struct tcp_sock, __cacheline_group_begin__tcp_sock_ kernel test robot
@ 2024-04-08 23:06 ` Vladimir Oltean
2024-04-09 5:08 ` Eric Dumazet
0 siblings, 1 reply; 8+ messages in thread
From: Vladimir Oltean @ 2024-04-08 23:06 UTC (permalink / raw)
To: Eric Dumazet; +Cc: kernel test robot, llvm, oe-kbuild-all, netdev
Hi Eric,
On Mon, Apr 08, 2024 at 10:49:35PM +0800, kernel test robot wrote:
> >> net/ipv4/tcp.c:4673:2: error: call to '__compiletime_assert_1030' declared with 'error' attribute: BUILD_BUG_ON failed: offsetof(struct tcp_sock, __cacheline_group_end__tcp_sock_write_txrx) - offsetofend(struct tcp_sock, __cacheline_group_begin__tcp_sock_write_txrx) > 92
> > 4673 CACHELINE_ASSERT_GROUP_SIZE(struct tcp_sock, tcp_sock_write_txrx, 92);
I can confirm the same compile time assertion with an armv7 gcc 7.3.1 compiler.
If I revert commit 86dad9aebd0d ("Revert "tcp: more struct tcp_sock adjustments")
it goes away.
Before the change (actually with it reverted), I can see that the
tcp_sock_write_txrx cacheline group begins at offset 1821 with a 3 byte
hole, and ends at offset 1897 (it has 76 bytes).
$ pahole -C tcp_sock $KBUILD_OUTPUT/net/ipv4/tcp.o
struct tcp_sock {
struct inet_connection_sock inet_conn __attribute__((__aligned__(8))); /* 0 1568 */
/* --- cacheline 24 boundary (1536 bytes) was 32 bytes ago --- */
__u8 __cacheline_group_begin__tcp_sock_read_tx[0]; /* 1568 0 */
u32 max_window; /* 1568 4 */
u32 rcv_ssthresh; /* 1572 4 */
u32 reordering; /* 1576 4 */
u32 notsent_lowat; /* 1580 4 */
u16 gso_segs; /* 1584 2 */
/* XXX 2 bytes hole, try to pack */
struct sk_buff * lost_skb_hint; /* 1588 4 */
struct sk_buff * retransmit_skb_hint; /* 1592 4 */
__u8 __cacheline_group_end__tcp_sock_read_tx[0]; /* 1596 0 */
__u8 __cacheline_group_begin__tcp_sock_read_txrx[0]; /* 1596 0 */
u32 tsoffset; /* 1596 4 */
/* --- cacheline 25 boundary (1600 bytes) --- */
u32 snd_wnd; /* 1600 4 */
u32 mss_cache; /* 1604 4 */
u32 snd_cwnd; /* 1608 4 */
u32 prr_out; /* 1612 4 */
u32 lost_out; /* 1616 4 */
u32 sacked_out; /* 1620 4 */
u16 tcp_header_len; /* 1624 2 */
u8 scaling_ratio; /* 1626 1 */
u8 chrono_type:2; /* 1627: 0 1 */
u8 repair:1; /* 1627: 2 1 */
u8 tcp_usec_ts:1; /* 1627: 3 1 */
u8 is_sack_reneg:1; /* 1627: 4 1 */
u8 is_cwnd_limited:1; /* 1627: 5 1 */
/* XXX 2 bits hole, try to pack */
__u8 __cacheline_group_end__tcp_sock_read_txrx[0]; /* 1628 0 */
__u8 __cacheline_group_begin__tcp_sock_read_rx[0]; /* 1628 0 */
u32 copied_seq; /* 1628 4 */
u32 rcv_tstamp; /* 1632 4 */
u32 snd_wl1; /* 1636 4 */
u32 tlp_high_seq; /* 1640 4 */
u32 rttvar_us; /* 1644 4 */
u32 retrans_out; /* 1648 4 */
u16 advmss; /* 1652 2 */
u16 urg_data; /* 1654 2 */
u32 lost; /* 1656 4 */
struct minmax rtt_min; /* 1660 24 */
/* --- cacheline 26 boundary (1664 bytes) was 20 bytes ago --- */
struct rb_root out_of_order_queue; /* 1684 4 */
u32 snd_ssthresh; /* 1688 4 */
__u8 __cacheline_group_end__tcp_sock_read_rx[0]; /* 1692 0 */
/* XXX 36 bytes hole, try to pack */
/* --- cacheline 27 boundary (1728 bytes) --- */
__u8 __cacheline_group_begin__tcp_sock_write_tx[0] __attribute__((__aligned__(64))); /* 1728 0 */
u32 segs_out; /* 1728 4 */
u32 data_segs_out; /* 1732 4 */
u64 bytes_sent; /* 1736 8 */
u32 snd_sml; /* 1744 4 */
u32 chrono_start; /* 1748 4 */
u32 chrono_stat[3]; /* 1752 12 */
u32 write_seq; /* 1764 4 */
u32 pushed_seq; /* 1768 4 */
u32 lsndtime; /* 1772 4 */
u32 mdev_us; /* 1776 4 */
u32 rtt_seq; /* 1780 4 */
u64 tcp_wstamp_ns; /* 1784 8 */
/* --- cacheline 28 boundary (1792 bytes) --- */
u64 tcp_clock_cache; /* 1792 8 */
u64 tcp_mstamp; /* 1800 8 */
struct list_head tsorted_sent_queue; /* 1808 8 */
struct sk_buff * highest_sack; /* 1816 4 */
u8 ecn_flags; /* 1820 1 */
__u8 __cacheline_group_end__tcp_sock_write_tx[0]; /* 1821 0 */
__u8 __cacheline_group_begin__tcp_sock_write_txrx[0]; /* 1821 0 */
/* XXX 3 bytes hole, try to pack */
__be32 pred_flags; /* 1824 4 */
u32 rcv_nxt; /* 1828 4 */
u32 snd_nxt; /* 1832 4 */
u32 snd_una; /* 1836 4 */
u32 window_clamp; /* 1840 4 */
u32 srtt_us; /* 1844 4 */
u32 packets_out; /* 1848 4 */
u32 snd_up; /* 1852 4 */
/* --- cacheline 29 boundary (1856 bytes) --- */
u32 delivered; /* 1856 4 */
u32 delivered_ce; /* 1860 4 */
u32 app_limited; /* 1864 4 */
u32 rcv_wnd; /* 1868 4 */
struct tcp_options_received rx_opt; /* 1872 24 */
u8 nonagle:4; /* 1896: 0 1 */
u8 rate_app_limited:1; /* 1896: 4 1 */
/* XXX 3 bits hole, try to pack */
__u8 __cacheline_group_end__tcp_sock_write_txrx[0]; /* 1897 0 */
/* XXX 7 bytes hole, try to pack */
__u8 __cacheline_group_begin__tcp_sock_write_rx[0] __attribute__((__aligned__(8))); /* 1904 0 */
u64 bytes_received; /* 1904 8 */
u32 segs_in; /* 1912 4 */
u32 data_segs_in; /* 1916 4 */
/* --- cacheline 30 boundary (1920 bytes) --- */
u32 rcv_wup; /* 1920 4 */
u32 max_packets_out; /* 1924 4 */
u32 cwnd_usage_seq; /* 1928 4 */
u32 rate_delivered; /* 1932 4 */
u32 rate_interval_us; /* 1936 4 */
u32 rcv_rtt_last_tsecr; /* 1940 4 */
u64 first_tx_mstamp; /* 1944 8 */
u64 delivered_mstamp; /* 1952 8 */
u64 bytes_acked; /* 1960 8 */
struct {
u32 rtt_us; /* 1968 4 */
u32 seq; /* 1972 4 */
u64 time; /* 1976 8 */
} rcv_rtt_est; /* 1968 16 */
/* --- cacheline 31 boundary (1984 bytes) --- */
struct {
u32 space; /* 1984 4 */
u32 seq; /* 1988 4 */
u64 time; /* 1992 8 */
} rcvq_space; /* 1984 16 */
__u8 __cacheline_group_end__tcp_sock_write_rx[0]; /* 2000 0 */
u32 dsack_dups; /* 2000 4 */
u32 compressed_ack_rcv_nxt; /* 2004 4 */
struct list_head tsq_node; /* 2008 8 */
struct tcp_rack rack; /* 2016 24 */
/* XXX last struct has 2 bytes of padding */
u8 compressed_ack; /* 2040 1 */
u8 dup_ack_counter:2; /* 2041: 0 1 */
u8 tlp_retrans:1; /* 2041: 2 1 */
u8 unused:5; /* 2041: 3 1 */
u8 thin_lto:1; /* 2042: 0 1 */
u8 recvmsg_inq:1; /* 2042: 1 1 */
u8 fastopen_connect:1; /* 2042: 2 1 */
u8 fastopen_no_cookie:1; /* 2042: 3 1 */
u8 fastopen_client_fail:2; /* 2042: 4 1 */
u8 frto:1; /* 2042: 6 1 */
/* XXX 1 bit hole, try to pack */
u8 repair_queue; /* 2043 1 */
u8 save_syn:2; /* 2044: 0 1 */
u8 syn_data:1; /* 2044: 2 1 */
u8 syn_fastopen:1; /* 2044: 3 1 */
u8 syn_fastopen_exp:1; /* 2044: 4 1 */
u8 syn_fastopen_ch:1; /* 2044: 5 1 */
u8 syn_data_acked:1; /* 2044: 6 1 */
/* XXX 1 bit hole, try to pack */
u8 keepalive_probes; /* 2045 1 */
/* XXX 2 bytes hole, try to pack */
/* --- cacheline 32 boundary (2048 bytes) --- */
u32 tcp_tx_delay; /* 2048 4 */
u32 mdev_max_us; /* 2052 4 */
u32 reord_seen; /* 2056 4 */
u32 snd_cwnd_cnt; /* 2060 4 */
u32 snd_cwnd_clamp; /* 2064 4 */
u32 snd_cwnd_used; /* 2068 4 */
u32 snd_cwnd_stamp; /* 2072 4 */
u32 prior_cwnd; /* 2076 4 */
u32 prr_delivered; /* 2080 4 */
u32 last_oow_ack_time; /* 2084 4 */
struct hrtimer pacing_timer __attribute__((__aligned__(8))); /* 2088 48 */
/* XXX last struct has 4 bytes of padding */
/* --- cacheline 33 boundary (2112 bytes) was 24 bytes ago --- */
struct hrtimer compressed_ack_timer __attribute__((__aligned__(8))); /* 2136 48 */
/* XXX last struct has 4 bytes of padding */
/* --- cacheline 34 boundary (2176 bytes) was 8 bytes ago --- */
struct sk_buff * ooo_last_skb; /* 2184 4 */
struct tcp_sack_block duplicate_sack[1]; /* 2188 8 */
struct tcp_sack_block selective_acks[4]; /* 2196 32 */
struct tcp_sack_block recv_sack_cache[4]; /* 2228 32 */
/* --- cacheline 35 boundary (2240 bytes) was 20 bytes ago --- */
int lost_cnt_hint; /* 2260 4 */
u32 prior_ssthresh; /* 2264 4 */
u32 high_seq; /* 2268 4 */
u32 retrans_stamp; /* 2272 4 */
u32 undo_marker; /* 2276 4 */
int undo_retrans; /* 2280 4 */
/* XXX 4 bytes hole, try to pack */
u64 bytes_retrans; /* 2288 8 */
u32 total_retrans; /* 2296 4 */
u32 rto_stamp; /* 2300 4 */
/* --- cacheline 36 boundary (2304 bytes) --- */
u16 total_rto; /* 2304 2 */
u16 total_rto_recoveries; /* 2306 2 */
u32 total_rto_time; /* 2308 4 */
u32 urg_seq; /* 2312 4 */
unsigned int keepalive_time; /* 2316 4 */
unsigned int keepalive_intvl; /* 2320 4 */
int linger2; /* 2324 4 */
u8 bpf_sock_ops_cb_flags; /* 2328 1 */
u8 bpf_chg_cc_inprogress:1; /* 2329: 0 1 */
/* XXX 7 bits hole, try to pack */
u16 timeout_rehash; /* 2330 2 */
u32 rcv_ooopack; /* 2332 4 */
struct {
u32 probe_seq_start; /* 2336 4 */
u32 probe_seq_end; /* 2340 4 */
} mtu_probe; /* 2336 8 */
u32 plb_rehash; /* 2344 4 */
u32 mtu_info; /* 2348 4 */
struct tcp_fastopen_request * fastopen_req; /* 2352 4 */
struct request_sock * fastopen_rsk; /* 2356 4 */
struct saved_syn * saved_syn; /* 2360 4 */
/* size: 2368, cachelines: 37, members: 156 */
/* sum members: 2304, holes: 6, sum holes: 54 */
/* sum bitfield members: 34 bits, bit holes: 5, sum bit holes: 14 bits */
/* padding: 4 */
/* paddings: 3, sum paddings: 10 */
/* forced alignments: 5, forced holes: 2, sum forced holes: 43 */
} __attribute__((__aligned__(64)));
After the change, it begins at 1805 and ends at 1901, thus triggering
the assertion (96 > 92):
struct tcp_sock {
struct inet_connection_sock inet_conn __attribute__((__aligned__(8))); /* 0 1568 */
/* --- cacheline 24 boundary (1536 bytes) was 32 bytes ago --- */
__u8 __cacheline_group_begin__tcp_sock_read_tx[0]; /* 1568 0 */
u32 max_window; /* 1568 4 */
u32 rcv_ssthresh; /* 1572 4 */
u32 reordering; /* 1576 4 */
u32 notsent_lowat; /* 1580 4 */
u16 gso_segs; /* 1584 2 */
/* XXX 2 bytes hole, try to pack */
struct sk_buff * lost_skb_hint; /* 1588 4 */
struct sk_buff * retransmit_skb_hint; /* 1592 4 */
__u8 __cacheline_group_end__tcp_sock_read_tx[0]; /* 1596 0 */
__u8 __cacheline_group_begin__tcp_sock_read_txrx[0]; /* 1596 0 */
u32 tsoffset; /* 1596 4 */
/* --- cacheline 25 boundary (1600 bytes) --- */
u32 snd_wnd; /* 1600 4 */
u32 mss_cache; /* 1604 4 */
u32 snd_cwnd; /* 1608 4 */
u32 prr_out; /* 1612 4 */
u32 lost_out; /* 1616 4 */
u32 sacked_out; /* 1620 4 */
u16 tcp_header_len; /* 1624 2 */
u8 scaling_ratio; /* 1626 1 */
u8 chrono_type:2; /* 1627: 0 1 */
u8 repair:1; /* 1627: 2 1 */
u8 tcp_usec_ts:1; /* 1627: 3 1 */
u8 is_sack_reneg:1; /* 1627: 4 1 */
u8 is_cwnd_limited:1; /* 1627: 5 1 */
/* XXX 2 bits hole, try to pack */
__u8 __cacheline_group_end__tcp_sock_read_txrx[0]; /* 1628 0 */
__u8 __cacheline_group_begin__tcp_sock_read_rx[0]; /* 1628 0 */
u32 copied_seq; /* 1628 4 */
u32 rcv_tstamp; /* 1632 4 */
u32 snd_wl1; /* 1636 4 */
u32 tlp_high_seq; /* 1640 4 */
u32 rttvar_us; /* 1644 4 */
u32 retrans_out; /* 1648 4 */
u16 advmss; /* 1652 2 */
u16 urg_data; /* 1654 2 */
u32 lost; /* 1656 4 */
struct minmax rtt_min; /* 1660 24 */
/* --- cacheline 26 boundary (1664 bytes) was 20 bytes ago --- */
struct rb_root out_of_order_queue; /* 1684 4 */
u32 snd_ssthresh; /* 1688 4 */
u8 recvmsg_inq:1; /* 1692: 0 1 */
/* XXX 7 bits hole, try to pack */
__u8 __cacheline_group_end__tcp_sock_read_rx[0]; /* 1693 0 */
/* XXX 35 bytes hole, try to pack */
/* --- cacheline 27 boundary (1728 bytes) --- */
__u8 __cacheline_group_begin__tcp_sock_write_tx[0] __attribute__((__aligned__(64))); /* 1728 0 */
u32 segs_out; /* 1728 4 */
u32 data_segs_out; /* 1732 4 */
u64 bytes_sent; /* 1736 8 */
u32 snd_sml; /* 1744 4 */
u32 chrono_start; /* 1748 4 */
u32 chrono_stat[3]; /* 1752 12 */
u32 write_seq; /* 1764 4 */
u32 pushed_seq; /* 1768 4 */
u32 lsndtime; /* 1772 4 */
u32 mdev_us; /* 1776 4 */
u32 rtt_seq; /* 1780 4 */
u64 tcp_wstamp_ns; /* 1784 8 */
/* --- cacheline 28 boundary (1792 bytes) --- */
struct list_head tsorted_sent_queue; /* 1792 8 */
struct sk_buff * highest_sack; /* 1800 4 */
u8 ecn_flags; /* 1804 1 */
__u8 __cacheline_group_end__tcp_sock_write_tx[0]; /* 1805 0 */
__u8 __cacheline_group_begin__tcp_sock_write_txrx[0]; /* 1805 0 */
/* XXX 3 bytes hole, try to pack */
__be32 pred_flags; /* 1808 4 */
/* XXX 4 bytes hole, try to pack */
u64 tcp_clock_cache; /* 1816 8 */
u64 tcp_mstamp; /* 1824 8 */
u32 rcv_nxt; /* 1832 4 */
u32 snd_nxt; /* 1836 4 */
u32 snd_una; /* 1840 4 */
u32 window_clamp; /* 1844 4 */
u32 srtt_us; /* 1848 4 */
u32 packets_out; /* 1852 4 */
/* --- cacheline 29 boundary (1856 bytes) --- */
u32 snd_up; /* 1856 4 */
u32 delivered; /* 1860 4 */
u32 delivered_ce; /* 1864 4 */
u32 app_limited; /* 1868 4 */
u32 rcv_wnd; /* 1872 4 */
struct tcp_options_received rx_opt; /* 1876 24 */
u8 nonagle:4; /* 1900: 0 1 */
u8 rate_app_limited:1; /* 1900: 4 1 */
/* XXX 3 bits hole, try to pack */
__u8 __cacheline_group_end__tcp_sock_write_txrx[0]; /* 1901 0 */
/* XXX 3 bytes hole, try to pack */
__u8 __cacheline_group_begin__tcp_sock_write_rx[0] __attribute__((__aligned__(8))); /* 1904 0 */
u64 bytes_received; /* 1904 8 */
u32 segs_in; /* 1912 4 */
u32 data_segs_in; /* 1916 4 */
/* --- cacheline 30 boundary (1920 bytes) --- */
u32 rcv_wup; /* 1920 4 */
u32 max_packets_out; /* 1924 4 */
u32 cwnd_usage_seq; /* 1928 4 */
u32 rate_delivered; /* 1932 4 */
u32 rate_interval_us; /* 1936 4 */
u32 rcv_rtt_last_tsecr; /* 1940 4 */
u64 first_tx_mstamp; /* 1944 8 */
u64 delivered_mstamp; /* 1952 8 */
u64 bytes_acked; /* 1960 8 */
struct {
u32 rtt_us; /* 1968 4 */
u32 seq; /* 1972 4 */
u64 time; /* 1976 8 */
} rcv_rtt_est; /* 1968 16 */
/* --- cacheline 31 boundary (1984 bytes) --- */
struct {
u32 space; /* 1984 4 */
u32 seq; /* 1988 4 */
u64 time; /* 1992 8 */
} rcvq_space; /* 1984 16 */
__u8 __cacheline_group_end__tcp_sock_write_rx[0]; /* 2000 0 */
u32 dsack_dups; /* 2000 4 */
u32 compressed_ack_rcv_nxt; /* 2004 4 */
struct list_head tsq_node; /* 2008 8 */
struct tcp_rack rack; /* 2016 24 */
/* XXX last struct has 2 bytes of padding */
u8 compressed_ack; /* 2040 1 */
u8 dup_ack_counter:2; /* 2041: 0 1 */
u8 tlp_retrans:1; /* 2041: 2 1 */
u8 unused:5; /* 2041: 3 1 */
u8 thin_lto:1; /* 2042: 0 1 */
u8 fastopen_connect:1; /* 2042: 1 1 */
u8 fastopen_no_cookie:1; /* 2042: 2 1 */
u8 fastopen_client_fail:2; /* 2042: 3 1 */
u8 frto:1; /* 2042: 5 1 */
/* XXX 2 bits hole, try to pack */
u8 repair_queue; /* 2043 1 */
u8 save_syn:2; /* 2044: 0 1 */
u8 syn_data:1; /* 2044: 2 1 */
u8 syn_fastopen:1; /* 2044: 3 1 */
u8 syn_fastopen_exp:1; /* 2044: 4 1 */
u8 syn_fastopen_ch:1; /* 2044: 5 1 */
u8 syn_data_acked:1; /* 2044: 6 1 */
/* XXX 1 bit hole, try to pack */
u8 keepalive_probes; /* 2045 1 */
/* XXX 2 bytes hole, try to pack */
/* --- cacheline 32 boundary (2048 bytes) --- */
u32 tcp_tx_delay; /* 2048 4 */
u32 mdev_max_us; /* 2052 4 */
u32 reord_seen; /* 2056 4 */
u32 snd_cwnd_cnt; /* 2060 4 */
u32 snd_cwnd_clamp; /* 2064 4 */
u32 snd_cwnd_used; /* 2068 4 */
u32 snd_cwnd_stamp; /* 2072 4 */
u32 prior_cwnd; /* 2076 4 */
u32 prr_delivered; /* 2080 4 */
u32 last_oow_ack_time; /* 2084 4 */
struct hrtimer pacing_timer __attribute__((__aligned__(8))); /* 2088 48 */
/* XXX last struct has 4 bytes of padding */
/* --- cacheline 33 boundary (2112 bytes) was 24 bytes ago --- */
struct hrtimer compressed_ack_timer __attribute__((__aligned__(8))); /* 2136 48 */
/* XXX last struct has 4 bytes of padding */
/* --- cacheline 34 boundary (2176 bytes) was 8 bytes ago --- */
struct sk_buff * ooo_last_skb; /* 2184 4 */
struct tcp_sack_block duplicate_sack[1]; /* 2188 8 */
struct tcp_sack_block selective_acks[4]; /* 2196 32 */
struct tcp_sack_block recv_sack_cache[4]; /* 2228 32 */
/* --- cacheline 35 boundary (2240 bytes) was 20 bytes ago --- */
int lost_cnt_hint; /* 2260 4 */
u32 prior_ssthresh; /* 2264 4 */
u32 high_seq; /* 2268 4 */
u32 retrans_stamp; /* 2272 4 */
u32 undo_marker; /* 2276 4 */
int undo_retrans; /* 2280 4 */
/* XXX 4 bytes hole, try to pack */
u64 bytes_retrans; /* 2288 8 */
u32 total_retrans; /* 2296 4 */
u32 rto_stamp; /* 2300 4 */
/* --- cacheline 36 boundary (2304 bytes) --- */
u16 total_rto; /* 2304 2 */
u16 total_rto_recoveries; /* 2306 2 */
u32 total_rto_time; /* 2308 4 */
u32 urg_seq; /* 2312 4 */
unsigned int keepalive_time; /* 2316 4 */
unsigned int keepalive_intvl; /* 2320 4 */
int linger2; /* 2324 4 */
u8 bpf_sock_ops_cb_flags; /* 2328 1 */
u8 bpf_chg_cc_inprogress:1; /* 2329: 0 1 */
/* XXX 7 bits hole, try to pack */
u16 timeout_rehash; /* 2330 2 */
u32 rcv_ooopack; /* 2332 4 */
struct {
u32 probe_seq_start; /* 2336 4 */
u32 probe_seq_end; /* 2340 4 */
} mtu_probe; /* 2336 8 */
u32 plb_rehash; /* 2344 4 */
u32 mtu_info; /* 2348 4 */
struct tcp_fastopen_request * fastopen_req; /* 2352 4 */
struct request_sock * fastopen_rsk; /* 2356 4 */
struct saved_syn * saved_syn; /* 2360 4 */
/* size: 2368, cachelines: 37, members: 156 */
/* sum members: 2304, holes: 7, sum holes: 53 */
/* sum bitfield members: 34 bits, bit holes: 6, sum bit holes: 22 bits */
/* padding: 4 */
/* paddings: 3, sum paddings: 10 */
/* forced alignments: 5, forced holes: 2, sum forced holes: 38 */
} __attribute__((__aligned__(64)));
It gained 20 bytes in the change. Most notably, it gained a 4 byte hole
between pred_flags and tcp_clock_cache.
I haven't followed the development of these optimizations, and I tried a
few trivial things, some of which didn't work, and some of which did.
Of those that worked, the most notable one was letting the 2 u64 fields,
tcp_clock_cache and tcp_mstamp, be the first members of the group, and
moving the __be32 pred_flags right below them.
Obviously my level of confidence in the fix is quite low, so it would be
great if you could cast an expert eye onto this.
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [net-next:main 26/50] net/ipv4/tcp.c:4673:2: error: call to '__compiletime_assert_1030' declared with 'error' attribute: BUILD_BUG_ON failed: offsetof(struct tcp_sock, __cacheline_group_end__tcp_sock_write_txrx) - offsetofend(struct tcp_sock, __cacheline_group_begin__tcp_sock_...
2024-04-08 23:06 ` Vladimir Oltean
@ 2024-04-09 5:08 ` Eric Dumazet
2024-04-10 17:28 ` Florian Fainelli
0 siblings, 1 reply; 8+ messages in thread
From: Eric Dumazet @ 2024-04-09 5:08 UTC (permalink / raw)
To: Vladimir Oltean; +Cc: kernel test robot, llvm, oe-kbuild-all, netdev
On Tue, Apr 9, 2024 at 1:06 AM Vladimir Oltean <olteanv@gmail.com> wrote:
>
> Hi Eric,
>
> On Mon, Apr 08, 2024 at 10:49:35PM +0800, kernel test robot wrote:
> > >> net/ipv4/tcp.c:4673:2: error: call to '__compiletime_assert_1030' declared with 'error' attribute: BUILD_BUG_ON failed: offsetof(struct tcp_sock, __cacheline_group_end__tcp_sock_write_txrx) - offsetofend(struct tcp_sock, __cacheline_group_begin__tcp_sock_write_txrx) > 92
> > > 4673 CACHELINE_ASSERT_GROUP_SIZE(struct tcp_sock, tcp_sock_write_txrx, 92);
>
> I can confirm the same compile time assertion with an armv7 gcc 7.3.1 compiler.
> If I revert commit 86dad9aebd0d ("Revert "tcp: more struct tcp_sock adjustments")
> it goes away.
>
> Before the change (actually with it reverted), I can see that the
> tcp_sock_write_txrx cacheline group begins at offset 1821 with a 3 byte
> hole, and ends at offset 1897 (it has 76 bytes).
...
> It gained 20 bytes in the change. Most notably, it gained a 4 byte hole
> between pred_flags and tcp_clock_cache.
>
> I haven't followed the development of these optimizations, and I tried a
> few trivial things, some of which didn't work, and some of which did.
> Of those that worked, the most notable one was letting the 2 u64 fields,
> tcp_clock_cache and tcp_mstamp, be the first members of the group, and
> moving the __be32 pred_flags right below them.
>
> Obviously my level of confidence in the fix is quite low, so it would be
> great if you could cast an expert eye onto this.
I am on it, do not worry, thanks !
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [net-next:main 26/50] net/ipv4/tcp.c:4673:2: error: call to '__compiletime_assert_1030' declared with 'error' attribute: BUILD_BUG_ON failed: offsetof(struct tcp_sock, __cacheline_group_end__tcp_sock_write_txrx) - offsetofend(struct tcp_sock, __cacheline_group_begin__tcp_sock_...
2024-04-09 5:08 ` Eric Dumazet
@ 2024-04-10 17:28 ` Florian Fainelli
2024-04-10 17:33 ` Eric Dumazet
0 siblings, 1 reply; 8+ messages in thread
From: Florian Fainelli @ 2024-04-10 17:28 UTC (permalink / raw)
To: Eric Dumazet, Vladimir Oltean, Jakub Kicinski
Cc: kernel test robot, llvm, oe-kbuild-all, netdev
On 4/8/2024 10:08 PM, Eric Dumazet wrote:
> On Tue, Apr 9, 2024 at 1:06 AM Vladimir Oltean <olteanv@gmail.com> wrote:
>>
>> Hi Eric,
>>
>> On Mon, Apr 08, 2024 at 10:49:35PM +0800, kernel test robot wrote:
>>>>> net/ipv4/tcp.c:4673:2: error: call to '__compiletime_assert_1030' declared with 'error' attribute: BUILD_BUG_ON failed: offsetof(struct tcp_sock, __cacheline_group_end__tcp_sock_write_txrx) - offsetofend(struct tcp_sock, __cacheline_group_begin__tcp_sock_write_txrx) > 92
>>>> 4673 CACHELINE_ASSERT_GROUP_SIZE(struct tcp_sock, tcp_sock_write_txrx, 92);
>>
>> I can confirm the same compile time assertion with an armv7 gcc 7.3.1 compiler.
>> If I revert commit 86dad9aebd0d ("Revert "tcp: more struct tcp_sock adjustments")
>> it goes away.
>>
>> Before the change (actually with it reverted), I can see that the
>> tcp_sock_write_txrx cacheline group begins at offset 1821 with a 3 byte
>> hole, and ends at offset 1897 (it has 76 bytes).
>
>
> ...
>
>> It gained 20 bytes in the change. Most notably, it gained a 4 byte hole
>> between pred_flags and tcp_clock_cache.
>>
>> I haven't followed the development of these optimizations, and I tried a
>> few trivial things, some of which didn't work, and some of which did.
>> Of those that worked, the most notable one was letting the 2 u64 fields,
>> tcp_clock_cache and tcp_mstamp, be the first members of the group, and
>> moving the __be32 pred_flags right below them.
>>
>> Obviously my level of confidence in the fix is quite low, so it would be
>> great if you could cast an expert eye onto this.
>
> I am on it, do not worry, thanks !
Also just got hit by this on an ARMv7 build configuration as well.
Jakub, I do not see a 32-bit build in the various checks being run for a
patch, could you add one, if nothing else a i386 build and a
multi_v7_defconfig build would get us a good build coverage.
Thanks!
--
Florian
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [net-next:main 26/50] net/ipv4/tcp.c:4673:2: error: call to '__compiletime_assert_1030' declared with 'error' attribute: BUILD_BUG_ON failed: offsetof(struct tcp_sock, __cacheline_group_end__tcp_sock_write_txrx) - offsetofend(struct tcp_sock, __cacheline_group_begin__tcp_sock_...
2024-04-10 17:28 ` Florian Fainelli
@ 2024-04-10 17:33 ` Eric Dumazet
2024-04-11 1:36 ` Jakub Kicinski
0 siblings, 1 reply; 8+ messages in thread
From: Eric Dumazet @ 2024-04-10 17:33 UTC (permalink / raw)
To: Florian Fainelli
Cc: Vladimir Oltean, Jakub Kicinski, kernel test robot, llvm,
oe-kbuild-all, netdev
On Wed, Apr 10, 2024 at 7:28 PM Florian Fainelli <f.fainelli@gmail.com> wrote:
>
>
>
> On 4/8/2024 10:08 PM, Eric Dumazet wrote:
> > On Tue, Apr 9, 2024 at 1:06 AM Vladimir Oltean <olteanv@gmail.com> wrote:
> >>
> >> Hi Eric,
> >>
> >> On Mon, Apr 08, 2024 at 10:49:35PM +0800, kernel test robot wrote:
> >>>>> net/ipv4/tcp.c:4673:2: error: call to '__compiletime_assert_1030' declared with 'error' attribute: BUILD_BUG_ON failed: offsetof(struct tcp_sock, __cacheline_group_end__tcp_sock_write_txrx) - offsetofend(struct tcp_sock, __cacheline_group_begin__tcp_sock_write_txrx) > 92
> >>>> 4673 CACHELINE_ASSERT_GROUP_SIZE(struct tcp_sock, tcp_sock_write_txrx, 92);
> >>
> >> I can confirm the same compile time assertion with an armv7 gcc 7.3.1 compiler.
> >> If I revert commit 86dad9aebd0d ("Revert "tcp: more struct tcp_sock adjustments")
> >> it goes away.
> >>
> >> Before the change (actually with it reverted), I can see that the
> >> tcp_sock_write_txrx cacheline group begins at offset 1821 with a 3 byte
> >> hole, and ends at offset 1897 (it has 76 bytes).
> >
> >
> > ...
> >
> >> It gained 20 bytes in the change. Most notably, it gained a 4 byte hole
> >> between pred_flags and tcp_clock_cache.
> >>
> >> I haven't followed the development of these optimizations, and I tried a
> >> few trivial things, some of which didn't work, and some of which did.
> >> Of those that worked, the most notable one was letting the 2 u64 fields,
> >> tcp_clock_cache and tcp_mstamp, be the first members of the group, and
> >> moving the __be32 pred_flags right below them.
> >>
> >> Obviously my level of confidence in the fix is quite low, so it would be
> >> great if you could cast an expert eye onto this.
> >
> > I am on it, do not worry, thanks !
>
> Also just got hit by this on an ARMv7 build configuration as well.
>
> Jakub, I do not see a 32-bit build in the various checks being run for a
> patch, could you add one, if nothing else a i386 build and a
> multi_v7_defconfig build would get us a good build coverage.
i386 build was just fine for me.
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [net-next:main 26/50] net/ipv4/tcp.c:4673:2: error: call to '__compiletime_assert_1030' declared with 'error' attribute: BUILD_BUG_ON failed: offsetof(struct tcp_sock, __cacheline_group_end__tcp_sock_write_txrx) - offsetofend(struct tcp_sock, __cacheline_group_begin__tcp_sock_...
2024-04-10 17:33 ` Eric Dumazet
@ 2024-04-11 1:36 ` Jakub Kicinski
2024-04-11 19:21 ` Florian Fainelli
0 siblings, 1 reply; 8+ messages in thread
From: Jakub Kicinski @ 2024-04-11 1:36 UTC (permalink / raw)
To: Eric Dumazet, Florian Fainelli
Cc: Vladimir Oltean, kernel test robot, llvm, oe-kbuild-all, netdev
On Wed, 10 Apr 2024 19:33:54 +0200 Eric Dumazet wrote:
> > Jakub, I do not see a 32-bit build in the various checks being run for a
> > patch, could you add one, if nothing else a i386 build and a
> > multi_v7_defconfig build would get us a good build coverage.
>
> i386 build was just fine for me.
Yes, we test i386 too, FWIW.
Florian, does arm32 break a lot? I may not be paying sufficient
attention. We can add more build tests but the CPU time we have
is unfortunately finite :(
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [net-next:main 26/50] net/ipv4/tcp.c:4673:2: error: call to '__compiletime_assert_1030' declared with 'error' attribute: BUILD_BUG_ON failed: offsetof(struct tcp_sock, __cacheline_group_end__tcp_sock_write_txrx) - offsetofend(struct tcp_sock, __cacheline_group_begin__tcp_sock_...
2024-04-11 1:36 ` Jakub Kicinski
@ 2024-04-11 19:21 ` Florian Fainelli
2024-04-12 1:37 ` Jakub Kicinski
0 siblings, 1 reply; 8+ messages in thread
From: Florian Fainelli @ 2024-04-11 19:21 UTC (permalink / raw)
To: Jakub Kicinski, Eric Dumazet
Cc: Vladimir Oltean, kernel test robot, llvm, oe-kbuild-all, netdev
On 4/10/24 18:36, Jakub Kicinski wrote:
> On Wed, 10 Apr 2024 19:33:54 +0200 Eric Dumazet wrote:
>>> Jakub, I do not see a 32-bit build in the various checks being run for a
>>> patch, could you add one, if nothing else a i386 build and a
>>> multi_v7_defconfig build would get us a good build coverage.
>>
>> i386 build was just fine for me.
>
> Yes, we test i386 too, FWIW.
>
> Florian, does arm32 break a lot? I may not be paying sufficient
> attention. We can add more build tests but the CPU time we have
> is unfortunately finite :(
Yes, that is why I mentioned multi_v7_defconfig, you an see the build
failure with that configuration. Of course Eric fixed it now, thanks!
--
Florian
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [net-next:main 26/50] net/ipv4/tcp.c:4673:2: error: call to '__compiletime_assert_1030' declared with 'error' attribute: BUILD_BUG_ON failed: offsetof(struct tcp_sock, __cacheline_group_end__tcp_sock_write_txrx) - offsetofend(struct tcp_sock, __cacheline_group_begin__tcp_sock_...
2024-04-11 19:21 ` Florian Fainelli
@ 2024-04-12 1:37 ` Jakub Kicinski
0 siblings, 0 replies; 8+ messages in thread
From: Jakub Kicinski @ 2024-04-12 1:37 UTC (permalink / raw)
To: Florian Fainelli
Cc: Eric Dumazet, Vladimir Oltean, kernel test robot, llvm,
oe-kbuild-all, netdev
On Thu, 11 Apr 2024 12:21:22 -0700 Florian Fainelli wrote:
> > Florian, does arm32 break a lot? I may not be paying sufficient
> > attention. We can add more build tests but the CPU time we have
> > is unfortunately finite :(
>
> Yes, that is why I mentioned multi_v7_defconfig, you an see the build
> failure with that configuration. Of course Eric fixed it now, thanks!
Would you be willing to type up a bash script along the lines of:
https://github.com/linux-netdev/nipa/blob/main/contest/tests/build-doc.sh
perhaps some inspiration from:
https://github.com/linux-netdev/nipa/blob/main/tests/patch/build_allmodconfig_warn/build_allmodconfig.sh
? (the former runs on the test branches the latter commit by commit)
^ permalink raw reply [flat|nested] 8+ messages in thread
end of thread, other threads:[~2024-04-12 1:37 UTC | newest]
Thread overview: 8+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2024-04-08 14:49 [net-next:main 26/50] net/ipv4/tcp.c:4673:2: error: call to '__compiletime_assert_1030' declared with 'error' attribute: BUILD_BUG_ON failed: offsetof(struct tcp_sock, __cacheline_group_end__tcp_sock_write_txrx) - offsetofend(struct tcp_sock, __cacheline_group_begin__tcp_sock_ kernel test robot
2024-04-08 23:06 ` Vladimir Oltean
2024-04-09 5:08 ` Eric Dumazet
2024-04-10 17:28 ` Florian Fainelli
2024-04-10 17:33 ` Eric Dumazet
2024-04-11 1:36 ` Jakub Kicinski
2024-04-11 19:21 ` Florian Fainelli
2024-04-12 1:37 ` Jakub Kicinski
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).