From 38163af068810b388f6723a681dfd8c7b3680d38 Mon Sep 17 00:00:00 2001 From: Kuniyuki Iwashima Date: Tue, 14 Oct 2025 23:54:58 +0000 Subject: bpf: Introduce SK_BPF_BYPASS_PROT_MEM. If a socket has sk->sk_bypass_prot_mem flagged, the socket opts out of the global protocol memory accounting. This is easily controlled by net.core.bypass_prot_mem sysctl, but it lacks flexibility. Let's support flagging (and clearing) sk->sk_bypass_prot_mem via bpf_setsockopt() at the BPF_CGROUP_INET_SOCK_CREATE hook. int val = 1; bpf_setsockopt(ctx, SOL_SOCKET, SK_BPF_BYPASS_PROT_MEM, &val, sizeof(val)); As with net.core.bypass_prot_mem, this is inherited to child sockets, and BPF always takes precedence over sysctl at socket(2) and accept(2). SK_BPF_BYPASS_PROT_MEM is only supported at BPF_CGROUP_INET_SOCK_CREATE and not supported on other hooks for some reasons: 1. UDP charges memory under sk->sk_receive_queue.lock instead of lock_sock() 2. Modifying the flag after skb is charged to sk requires such adjustment during bpf_setsockopt() and complicates the logic unnecessarily We can support other hooks later if a real use case justifies that. Most changes are inline and hard to trace, but a microbenchmark on __sk_mem_raise_allocated() during neper/tcp_stream showed that more samples completed faster with sk->sk_bypass_prot_mem == 1. This will be more visible under tcp_mem pressure (but it's not a fair comparison). # bpftrace -e 'kprobe:__sk_mem_raise_allocated { @start[tid] = nsecs; } kretprobe:__sk_mem_raise_allocated /@start[tid]/ { @end[tid] = nsecs - @start[tid]; @times = hist(@end[tid]); delete(@start[tid]); }' # tcp_stream -6 -F 1000 -N -T 256 Without bpf prog: [128, 256) 3846 | | [256, 512) 1505326 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@| [512, 1K) 1371006 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ | [1K, 2K) 198207 |@@@@@@ | [2K, 4K) 31199 |@ | With bpf prog in the next patch: (must be attached before tcp_stream) # bpftool prog load sk_bypass_prot_mem.bpf.o /sys/fs/bpf/test type cgroup/sock_create # bpftool cgroup attach /sys/fs/cgroup/test cgroup_inet_sock_create pinned /sys/fs/bpf/test [128, 256) 6413 | | [256, 512) 1868425 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@| [512, 1K) 1101697 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ | [1K, 2K) 117031 |@@@@ | [2K, 4K) 11773 | | Signed-off-by: Kuniyuki Iwashima Signed-off-by: Martin KaFai Lau Acked-by: Roman Gushchin Link: https://patch.msgid.link/20251014235604.3057003-6-kuniyu@google.com --- tools/include/uapi/linux/bpf.h | 1 + 1 file changed, 1 insertion(+) (limited to 'tools/include/uapi/linux') diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 6829936d33f5..9b17d937edf7 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -7200,6 +7200,7 @@ enum { TCP_BPF_SYN_MAC = 1007, /* Copy the MAC, IP[46], and TCP header */ TCP_BPF_SOCK_OPS_CB_FLAGS = 1008, /* Get or Set TCP sock ops flags */ SK_BPF_CB_FLAGS = 1009, /* Get or set sock ops flags in socket */ + SK_BPF_BYPASS_PROT_MEM = 1010, /* Get or Set sk->sk_bypass_prot_mem */ }; enum { -- cgit v1.2.3 From c18d4b190a46651726c9a952667c74d2deb33c28 Mon Sep 17 00:00:00 2001 From: Samiullah Khawaja Date: Tue, 28 Oct 2025 20:30:05 +0000 Subject: net: Extend NAPI threaded polling to allow kthread based busy polling Add a new state NAPI_STATE_THREADED_BUSY_POLL to the NAPI state enum to enable and disable threaded busy polling. When threaded busy polling is enabled for a NAPI, enable NAPI_STATE_THREADED also. When the threaded NAPI is scheduled, set NAPI_STATE_IN_BUSY_POLL to signal napi_complete_done not to rearm interrupts. Whenever NAPI_STATE_THREADED_BUSY_POLL is unset, the NAPI_STATE_IN_BUSY_POLL will be unset, napi_complete_done unsets the NAPI_STATE_SCHED_THREADED bit also, which in turn will make the kthread go to sleep. Signed-off-by: Samiullah Khawaja Reviewed-by: Willem de Bruijn Acked-by: Martin Karsten Tested-by: Martin Karsten Link: https://patch.msgid.link/20251028203007.575686-2-skhawaja@google.com Signed-off-by: Jakub Kicinski --- tools/include/uapi/linux/netdev.h | 1 + 1 file changed, 1 insertion(+) (limited to 'tools/include/uapi/linux') diff --git a/tools/include/uapi/linux/netdev.h b/tools/include/uapi/linux/netdev.h index 48eb49aa03d4..048c8de1a130 100644 --- a/tools/include/uapi/linux/netdev.h +++ b/tools/include/uapi/linux/netdev.h @@ -80,6 +80,7 @@ enum netdev_qstats_scope { enum netdev_napi_threaded { NETDEV_NAPI_THREADED_DISABLED, NETDEV_NAPI_THREADED_ENABLED, + NETDEV_NAPI_THREADED_BUSY_POLL, }; enum { -- cgit v1.2.3 From 68e83f3472667aac18d577587102f4bf77d0bd06 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Asbj=C3=B8rn=20Sloth=20T=C3=B8nnesen?= Date: Thu, 20 Nov 2025 17:44:27 +0000 Subject: tools: ynl-gen: add regeneration comment MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add a comment on regeneration to the generated files. The comment is placed after the YNL-GEN line[1], as to not interfere with ynl-regen.sh's detection logic. [1] and after the optional YNL-ARG line. Link: https://lore.kernel.org/r/aR5m174O7pklKrMR@zx2c4.com/ Suggested-by: Jason A. Donenfeld Signed-off-by: Asbjørn Sloth Tønnesen Acked-by: Matthieu Baerts (NGI0) Link: https://patch.msgid.link/20251120174429.390574-3-ast@fiberby.net Signed-off-by: Jakub Kicinski --- tools/include/uapi/linux/netdev.h | 1 + 1 file changed, 1 insertion(+) (limited to 'tools/include/uapi/linux') diff --git a/tools/include/uapi/linux/netdev.h b/tools/include/uapi/linux/netdev.h index 048c8de1a130..e0b579a1df4f 100644 --- a/tools/include/uapi/linux/netdev.h +++ b/tools/include/uapi/linux/netdev.h @@ -2,6 +2,7 @@ /* Do not edit directly, auto-generated from: */ /* Documentation/netlink/specs/netdev.yaml */ /* YNL-GEN uapi header */ +/* To regenerate run: tools/net/ynl/ynl-regen.sh */ #ifndef _UAPI_LINUX_NETDEV_H #define _UAPI_LINUX_NETDEV_H -- cgit v1.2.3