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2024-12-12xdp: get rid of xdp_frame::mem.idAlexander Lobakin
Initially, xdp_frame::mem.id was used to search for the corresponding &page_pool to return the page correctly. However, after that struct page was extended to have a direct pointer to its PP (netmem has it as well), further keeping of this field makes no sense. xdp_return_frame_bulk() still used it to do a lookup, and this leftover is now removed. Remove xdp_frame::mem and replace it with ::mem_type, as only memory type still matters and we need to know it to be able to free the frame correctly. As a cute side effect, we can now make every scalar field in &xdp_frame of 4 byte width, speeding up accesses to them. Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com> Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com> Link: https://patch.msgid.link/20241211172649.761483-3-aleksander.lobakin@intel.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-09-11bpf, cpumap: Move xdp:xdp_cpumap_kthread tracepoint before rcvDaniel Xu
cpumap takes RX processing out of softirq and onto a separate kthread. Since the kthread needs to be scheduled in order to run (versus softirq which does not), we can theoretically experience extra latency if the system is under load and the scheduler is being unfair to us. Moving the tracepoint to before passing the skb list up the stack allows users to more accurately measure enqueue/dequeue latency introduced by cpumap via xdp:xdp_cpumap_enqueue and xdp:xdp_cpumap_kthread tracepoints. f9419f7bd7a5 ("bpf: cpumap add tracepoints") which added the tracepoints states that the intent behind them was for general observability and for a feedback loop to see if the queues are being overwhelmed. This change does not mess with either of those use cases but rather adds a third one. Signed-off-by: Daniel Xu <dxu@dxuuu.xyz> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Jesper Dangaard Brouer <hawk@kernel.org> Link: https://lore.kernel.org/bpf/47615d5b5e302e4bd30220473779e98b492d47cd.1725585718.git.dxu@dxuuu.xyz
2024-07-02net: Move flush list retrieval to where it is used.Sebastian Andrzej Siewior
The bpf_net_ctx_get_.*_flush_list() are used at the top of the function. This means the variable is always assigned even if unused. By moving the function to where it is used, it is possible to delay the initialisation until it is unavoidable. Not sure how much this gains in reality but by looking at bq_enqueue() (in devmap.c) gcc pushes one register less to the stack. \o/. Move flush list retrieval to where it is used. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Acked-by: Jesper Dangaard Brouer <hawk@kernel.org> Reviewed-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-07-02net: Optimize xdp_do_flush() with bpf_net_context infos.Sebastian Andrzej Siewior
Every NIC driver utilizing XDP should invoke xdp_do_flush() after processing all packages. With the introduction of the bpf_net_context logic the flush lists (for dev, CPU-map and xsk) are lazy initialized only if used. However xdp_do_flush() tries to flush all three of them so all three lists are always initialized and the likely empty lists are "iterated". Without the usage of XDP but with CONFIG_DEBUG_NET the lists are also initialized due to xdp_do_check_flushed(). Jakub suggest to utilize the hints in bpf_net_context and avoid invoking the flush function. This will also avoiding initializing the lists which are otherwise unused. Introduce bpf_net_ctx_get_all_used_flush_lists() to return the individual list if not-empty. Use the logic in xdp_do_flush() and xdp_do_check_flushed(). Remove the not needed .*_check_flush(). Suggested-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Reviewed-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-06-24net: Move per-CPU flush-lists to bpf_net_context on PREEMPT_RT.Sebastian Andrzej Siewior
The per-CPU flush lists, which are accessed from within the NAPI callback (xdp_do_flush() for instance), are per-CPU. There are subject to the same problem as struct bpf_redirect_info. Add the per-CPU lists cpu_map_flush_list, dev_map_flush_list and xskmap_map_flush_list to struct bpf_net_context. Add wrappers for the access. The lists initialized on first usage (similar to bpf_net_ctx_get_ri()). Cc: "Björn Töpel" <bjorn@kernel.org> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Andrii Nakryiko <andrii@kernel.org> Cc: Eduard Zingerman <eddyz87@gmail.com> Cc: Hao Luo <haoluo@google.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Jonathan Lemon <jonathan.lemon@gmail.com> Cc: KP Singh <kpsingh@kernel.org> Cc: Maciej Fijalkowski <maciej.fijalkowski@intel.com> Cc: Magnus Karlsson <magnus.karlsson@intel.com> Cc: Martin KaFai Lau <martin.lau@linux.dev> Cc: Song Liu <song@kernel.org> Cc: Stanislav Fomichev <sdf@google.com> Cc: Yonghong Song <yonghong.song@linux.dev> Acked-by: Jesper Dangaard Brouer <hawk@kernel.org> Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Link: https://patch.msgid.link/20240620132727.660738-16-bigeasy@linutronix.de Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-24net: Reference bpf_redirect_info via task_struct on PREEMPT_RT.Sebastian Andrzej Siewior
The XDP redirect process is two staged: - bpf_prog_run_xdp() is invoked to run a eBPF program which inspects the packet and makes decisions. While doing that, the per-CPU variable bpf_redirect_info is used. - Afterwards xdp_do_redirect() is invoked and accesses bpf_redirect_info and it may also access other per-CPU variables like xskmap_flush_list. At the very end of the NAPI callback, xdp_do_flush() is invoked which does not access bpf_redirect_info but will touch the individual per-CPU lists. The per-CPU variables are only used in the NAPI callback hence disabling bottom halves is the only protection mechanism. Users from preemptible context (like cpu_map_kthread_run()) explicitly disable bottom halves for protections reasons. Without locking in local_bh_disable() on PREEMPT_RT this data structure requires explicit locking. PREEMPT_RT has forced-threaded interrupts enabled and every NAPI-callback runs in a thread. If each thread has its own data structure then locking can be avoided. Create a struct bpf_net_context which contains struct bpf_redirect_info. Define the variable on stack, use bpf_net_ctx_set() to save a pointer to it, bpf_net_ctx_clear() removes it again. The bpf_net_ctx_set() may nest. For instance a function can be used from within NET_RX_SOFTIRQ/ net_rx_action which uses bpf_net_ctx_set() and NET_TX_SOFTIRQ which does not. Therefore only the first invocations updates the pointer. Use bpf_net_ctx_get_ri() as a wrapper to retrieve the current struct bpf_redirect_info. The returned data structure is zero initialized to ensure nothing is leaked from stack. This is done on first usage of the struct. bpf_net_ctx_set() sets bpf_redirect_info::kern_flags to 0 to note that initialisation is required. First invocation of bpf_net_ctx_get_ri() will memset() the data structure and update bpf_redirect_info::kern_flags. bpf_redirect_info::nh is excluded from memset because it is only used once BPF_F_NEIGH is set which also sets the nh member. The kern_flags is moved past nh to exclude it from memset. The pointer to bpf_net_context is saved task's task_struct. Using always the bpf_net_context approach has the advantage that there is almost zero differences between PREEMPT_RT and non-PREEMPT_RT builds. Cc: Andrii Nakryiko <andrii@kernel.org> Cc: Eduard Zingerman <eddyz87@gmail.com> Cc: Hao Luo <haoluo@google.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: John Fastabend <john.fastabend@gmail.com> Cc: KP Singh <kpsingh@kernel.org> Cc: Martin KaFai Lau <martin.lau@linux.dev> Cc: Song Liu <song@kernel.org> Cc: Stanislav Fomichev <sdf@google.com> Cc: Yonghong Song <yonghong.song@linux.dev> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Jesper Dangaard Brouer <hawk@kernel.org> Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Link: https://patch.msgid.link/20240620132727.660738-15-bigeasy@linutronix.de Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-03-20bpf: report RCU QS in cpumap kthreadYan Zhai
When there are heavy load, cpumap kernel threads can be busy polling packets from redirect queues and block out RCU tasks from reaching quiescent states. It is insufficient to just call cond_resched() in such context. Periodically raise a consolidated RCU QS before cond_resched fixes the problem. Fixes: 6710e1126934 ("bpf: introduce new bpf cpu map type BPF_MAP_TYPE_CPUMAP") Reviewed-by: Jesper Dangaard Brouer <hawk@kernel.org> Signed-off-by: Yan Zhai <yan@cloudflare.com> Acked-by: Paul E. McKenney <paulmck@kernel.org> Acked-by: Jesper Dangaard Brouer <hawk@kernel.org> Link: https://lore.kernel.org/r/c17b9f1517e19d813da3ede5ed33ee18496bb5d8.1710877680.git.yan@cloudflare.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-03-07net: move skbuff_cache(s) to net_hotdataEric Dumazet
skbuff_cache, skbuff_fclone_cache and skb_small_head_cache are used in rx/tx fast paths. Move them to net_hotdata for better cache locality. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20240306160031.874438-11-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-03-05cpumap: Zero-initialise xdp_rxq_info struct before running XDP programToke Høiland-Jørgensen
When running an XDP program that is attached to a cpumap entry, we don't initialise the xdp_rxq_info data structure being used in the xdp_buff that backs the XDP program invocation. Tobias noticed that this leads to random values being returned as the xdp_md->rx_queue_index value for XDP programs running in a cpumap. This means we're basically returning the contents of the uninitialised memory, which is bad. Fix this by zero-initialising the rxq data structure before running the XDP program. Fixes: 9216477449f3 ("bpf: cpumap: Add the possibility to attach an eBPF program to cpumap") Reported-by: Tobias Böhm <tobias@aibor.de> Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://lore.kernel.org/r/20240305213132.11955-1-toke@redhat.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-10-17net, bpf: Add a warning if NAPI cb missed xdp_do_flush().Sebastian Andrzej Siewior
A few drivers were missing a xdp_do_flush() invocation after XDP_REDIRECT. Add three helper functions each for one of the per-CPU lists. Return true if the per-CPU list is non-empty and flush the list. Add xdp_do_check_flushed() which invokes each helper functions and creates a warning if one of the functions had a non-empty list. Hide everything behind CONFIG_DEBUG_NET. Suggested-by: Jesper Dangaard Brouer <hawk@kernel.org> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com> Acked-by: Jakub Kicinski <kuba@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20231016125738.Yt79p1uF@linutronix.de
2023-08-21bpf, cpumask: Clean up bpf_cpu_map_entry directly in cpu_map_freeHou Tao
After synchronous_rcu(), both the dettached XDP program and xdp_do_flush() are completed, and the only user of bpf_cpu_map_entry will be cpu_map_kthread_run(), so instead of calling __cpu_map_entry_replace() to stop kthread and cleanup entry after a RCU grace period, do these things directly. Signed-off-by: Hou Tao <houtao1@huawei.com> Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://lore.kernel.org/r/20230816045959.358059-3-houtao@huaweicloud.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-08-21bpf, cpumap: Use queue_rcu_work() to remove unnecessary rcu_barrier()Hou Tao
As for now __cpu_map_entry_replace() uses call_rcu() to wait for the inflight xdp program to exit the RCU read critical section, and then launch kworker cpu_map_kthread_stop() to call kthread_stop() to flush all pending xdp frames or skbs. But it is unnecessary to use rcu_barrier() in cpu_map_kthread_stop() to wait for the completion of __cpu_map_entry_free(), because rcu_barrier() will wait for all pending RCU callbacks and cpu_map_kthread_stop() only needs to wait for the completion of a specific __cpu_map_entry_free(). So use queue_rcu_work() to replace call_rcu(), schedule_work() and rcu_barrier(). queue_rcu_work() will queue a __cpu_map_entry_free() kworker after a RCU grace period. Because __cpu_map_entry_free() is running in a kworker context, so it is OK to do all of these freeing procedures include kthread_stop() in it. After the update, there is no need to do reference-counting for bpf_cpu_map_entry, because bpf_cpu_map_entry is freed directly in __cpu_map_entry_free(), so just remove it. Signed-off-by: Hou Tao <houtao1@huawei.com> Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://lore.kernel.org/r/20230816045959.358059-2-houtao@huaweicloud.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-08-03Merge tag 'for-netdev' of ↵Jakub Kicinski
https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Martin KaFai Lau says: ==================== pull-request: bpf-next 2023-08-03 We've added 54 non-merge commits during the last 10 day(s) which contain a total of 84 files changed, 4026 insertions(+), 562 deletions(-). The main changes are: 1) Add SO_REUSEPORT support for TC bpf_sk_assign from Lorenz Bauer, Daniel Borkmann 2) Support new insns from cpu v4 from Yonghong Song 3) Non-atomically allocate freelist during prefill from YiFei Zhu 4) Support defragmenting IPv(4|6) packets in BPF from Daniel Xu 5) Add tracepoint to xdp attaching failure from Leon Hwang 6) struct netdev_rx_queue and xdp.h reshuffling to reduce rebuild time from Jakub Kicinski * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (54 commits) net: invert the netdevice.h vs xdp.h dependency net: move struct netdev_rx_queue out of netdevice.h eth: add missing xdp.h includes in drivers selftests/bpf: Add testcase for xdp attaching failure tracepoint bpf, xdp: Add tracepoint to xdp attaching failure selftests/bpf: fix static assert compilation issue for test_cls_*.c bpf: fix bpf_probe_read_kernel prototype mismatch riscv, bpf: Adapt bpf trampoline to optimized riscv ftrace framework libbpf: fix typos in Makefile tracing: bpf: use struct trace_entry in struct syscall_tp_t bpf, devmap: Remove unused dtab field from bpf_dtab_netdev bpf, cpumap: Remove unused cmap field from bpf_cpu_map_entry netfilter: bpf: Only define get_proto_defrag_hook() if necessary bpf: Fix an array-index-out-of-bounds issue in disasm.c net: remove duplicate INDIRECT_CALLABLE_DECLARE of udp[6]_ehashfn docs/bpf: Fix malformed documentation bpf: selftests: Add defrag selftests bpf: selftests: Support custom type and proto for client sockets bpf: selftests: Support not connecting client socket netfilter: bpf: Support BPF_F_NETFILTER_IP_DEFRAG in netfilter link ... ==================== Link: https://lore.kernel.org/r/20230803174845.825419-1-martin.lau@linux.dev Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-07-31bpf, cpumap: Remove unused cmap field from bpf_cpu_map_entryHou Tao
Since commit cdfafe98cabe ("xdp: Make cpumap flush_list common for all map instances"), cmap is no longer used, so just remove it. Signed-off-by: Hou Tao <houtao1@huawei.com> Acked-by: Jesper Dangaard Brouer <hawk@kernel.org> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/r/20230728014942.892272-2-houtao@huaweicloud.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-07-31bpf, cpumap: Handle skb as well when clean up ptr_ringHou Tao
The following warning was reported when running xdp_redirect_cpu with both skb-mode and stress-mode enabled: ------------[ cut here ]------------ Incorrect XDP memory type (-2128176192) usage WARNING: CPU: 7 PID: 1442 at net/core/xdp.c:405 Modules linked in: CPU: 7 PID: 1442 Comm: kworker/7:0 Tainted: G 6.5.0-rc2+ #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) Workqueue: events __cpu_map_entry_free RIP: 0010:__xdp_return+0x1e4/0x4a0 ...... Call Trace: <TASK> ? show_regs+0x65/0x70 ? __warn+0xa5/0x240 ? __xdp_return+0x1e4/0x4a0 ...... xdp_return_frame+0x4d/0x150 __cpu_map_entry_free+0xf9/0x230 process_one_work+0x6b0/0xb80 worker_thread+0x96/0x720 kthread+0x1a5/0x1f0 ret_from_fork+0x3a/0x70 ret_from_fork_asm+0x1b/0x30 </TASK> The reason for the warning is twofold. One is due to the kthread cpu_map_kthread_run() is stopped prematurely. Another one is __cpu_map_ring_cleanup() doesn't handle skb mode and treats skbs in ptr_ring as XDP frames. Prematurely-stopped kthread will be fixed by the preceding patch and ptr_ring will be empty when __cpu_map_ring_cleanup() is called. But as the comments in __cpu_map_ring_cleanup() said, handling and freeing skbs in ptr_ring as well to "catch any broken behaviour gracefully". Fixes: 11941f8a8536 ("bpf: cpumap: Implement generic cpumap") Signed-off-by: Hou Tao <houtao1@huawei.com> Acked-by: Jesper Dangaard Brouer <hawk@kernel.org> Link: https://lore.kernel.org/r/20230729095107.1722450-3-houtao@huaweicloud.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-07-31bpf, cpumap: Make sure kthread is running before map update returnsHou Tao
The following warning was reported when running stress-mode enabled xdp_redirect_cpu with some RT threads: ------------[ cut here ]------------ WARNING: CPU: 4 PID: 65 at kernel/bpf/cpumap.c:135 CPU: 4 PID: 65 Comm: kworker/4:1 Not tainted 6.5.0-rc2+ #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) Workqueue: events cpu_map_kthread_stop RIP: 0010:put_cpu_map_entry+0xda/0x220 ...... Call Trace: <TASK> ? show_regs+0x65/0x70 ? __warn+0xa5/0x240 ...... ? put_cpu_map_entry+0xda/0x220 cpu_map_kthread_stop+0x41/0x60 process_one_work+0x6b0/0xb80 worker_thread+0x96/0x720 kthread+0x1a5/0x1f0 ret_from_fork+0x3a/0x70 ret_from_fork_asm+0x1b/0x30 </TASK> The root cause is the same as commit 436901649731 ("bpf: cpumap: Fix memory leak in cpu_map_update_elem"). The kthread is stopped prematurely by kthread_stop() in cpu_map_kthread_stop(), and kthread() doesn't call cpu_map_kthread_run() at all but XDP program has already queued some frames or skbs into ptr_ring. So when __cpu_map_ring_cleanup() checks the ptr_ring, it will find it was not emptied and report a warning. An alternative fix is to use __cpu_map_ring_cleanup() to drop these pending frames or skbs when kthread_stop() returns -EINTR, but it may confuse the user, because these frames or skbs have been handled correctly by XDP program. So instead of dropping these frames or skbs, just make sure the per-cpu kthread is running before __cpu_map_entry_alloc() returns. After apply the fix, the error handle for kthread_stop() will be unnecessary because it will always return 0, so just remove it. Fixes: 6710e1126934 ("bpf: introduce new bpf cpu map type BPF_MAP_TYPE_CPUMAP") Signed-off-by: Hou Tao <houtao1@huawei.com> Reviewed-by: Pu Lehui <pulehui@huawei.com> Acked-by: Jesper Dangaard Brouer <hawk@kernel.org> Link: https://lore.kernel.org/r/20230729095107.1722450-2-houtao@huaweicloud.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-07-11bpf: cpumap: Fix memory leak in cpu_map_update_elemPu Lehui
Syzkaller reported a memory leak as follows: BUG: memory leak unreferenced object 0xff110001198ef748 (size 192): comm "syz-executor.3", pid 17672, jiffies 4298118891 (age 9.906s) hex dump (first 32 bytes): 00 00 00 00 4a 19 00 00 80 ad e3 e4 fe ff c0 00 ....J........... 00 b2 d3 0c 01 00 11 ff 28 f5 8e 19 01 00 11 ff ........(....... backtrace: [<ffffffffadd28087>] __cpu_map_entry_alloc+0xf7/0xb00 [<ffffffffadd28d8e>] cpu_map_update_elem+0x2fe/0x3d0 [<ffffffffadc6d0fd>] bpf_map_update_value.isra.0+0x2bd/0x520 [<ffffffffadc7349b>] map_update_elem+0x4cb/0x720 [<ffffffffadc7d983>] __se_sys_bpf+0x8c3/0xb90 [<ffffffffb029cc80>] do_syscall_64+0x30/0x40 [<ffffffffb0400099>] entry_SYSCALL_64_after_hwframe+0x61/0xc6 BUG: memory leak unreferenced object 0xff110001198ef528 (size 192): comm "syz-executor.3", pid 17672, jiffies 4298118891 (age 9.906s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffffffadd281f0>] __cpu_map_entry_alloc+0x260/0xb00 [<ffffffffadd28d8e>] cpu_map_update_elem+0x2fe/0x3d0 [<ffffffffadc6d0fd>] bpf_map_update_value.isra.0+0x2bd/0x520 [<ffffffffadc7349b>] map_update_elem+0x4cb/0x720 [<ffffffffadc7d983>] __se_sys_bpf+0x8c3/0xb90 [<ffffffffb029cc80>] do_syscall_64+0x30/0x40 [<ffffffffb0400099>] entry_SYSCALL_64_after_hwframe+0x61/0xc6 BUG: memory leak unreferenced object 0xff1100010fd93d68 (size 8): comm "syz-executor.3", pid 17672, jiffies 4298118891 (age 9.906s) hex dump (first 8 bytes): 00 00 00 00 00 00 00 00 ........ backtrace: [<ffffffffade5db3e>] kvmalloc_node+0x11e/0x170 [<ffffffffadd28280>] __cpu_map_entry_alloc+0x2f0/0xb00 [<ffffffffadd28d8e>] cpu_map_update_elem+0x2fe/0x3d0 [<ffffffffadc6d0fd>] bpf_map_update_value.isra.0+0x2bd/0x520 [<ffffffffadc7349b>] map_update_elem+0x4cb/0x720 [<ffffffffadc7d983>] __se_sys_bpf+0x8c3/0xb90 [<ffffffffb029cc80>] do_syscall_64+0x30/0x40 [<ffffffffb0400099>] entry_SYSCALL_64_after_hwframe+0x61/0xc6 In the cpu_map_update_elem flow, when kthread_stop is called before calling the threadfn of rcpu->kthread, since the KTHREAD_SHOULD_STOP bit of kthread has been set by kthread_stop, the threadfn of rcpu->kthread will never be executed, and rcpu->refcnt will never be 0, which will lead to the allocated rcpu, rcpu->queue and rcpu->queue->queue cannot be released. Calling kthread_stop before executing kthread's threadfn will return -EINTR. We can complete the release of memory resources in this state. Fixes: 6710e1126934 ("bpf: introduce new bpf cpu map type BPF_MAP_TYPE_CPUMAP") Signed-off-by: Pu Lehui <pulehui@huawei.com> Acked-by: Jesper Dangaard Brouer <hawk@kernel.org> Acked-by: Hou Tao <houtao1@huawei.com> Link: https://lore.kernel.org/r/20230711115848.2701559-1-pulehui@huaweicloud.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-06-19bpf: Centralize permissions checks for all BPF map typesAndrii Nakryiko
This allows to do more centralized decisions later on, and generally makes it very explicit which maps are privileged and which are not (e.g., LRU_HASH and LRU_PERCPU_HASH, which are privileged HASH variants, as opposed to unprivileged HASH and HASH_PERCPU; now this is explicit and easy to verify). Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Stanislav Fomichev <sdf@google.com> Link: https://lore.kernel.org/bpf/20230613223533.3689589-4-andrii@kernel.org
2023-03-22bpf: return long from bpf_map_ops funcsJP Kobryn
This patch changes the return types of bpf_map_ops functions to long, where previously int was returned. Using long allows for bpf programs to maintain the sign bit in the absence of sign extension during situations where inlined bpf helper funcs make calls to the bpf_map_ops funcs and a negative error is returned. The definitions of the helper funcs are generated from comments in the bpf uapi header at `include/uapi/linux/bpf.h`. The return type of these helpers was previously changed from int to long in commit bdb7b79b4ce8. For any case where one of the map helpers call the bpf_map_ops funcs that are still returning 32-bit int, a compiler might not include sign extension instructions to properly convert the 32-bit negative value a 64-bit negative value. For example: bpf assembly excerpt of an inlined helper calling a kernel function and checking for a specific error: ; err = bpf_map_update_elem(&mymap, &key, &val, BPF_NOEXIST); ... 46: call 0xffffffffe103291c ; htab_map_update_elem ; if (err && err != -EEXIST) { 4b: cmp $0xffffffffffffffef,%rax ; cmp -EEXIST,%rax kernel function assembly excerpt of return value from `htab_map_update_elem` returning 32-bit int: movl $0xffffffef, %r9d ... movl %r9d, %eax ...results in the comparison: cmp $0xffffffffffffffef, $0x00000000ffffffef Fixes: bdb7b79b4ce8 ("bpf: Switch most helper return values from 32-bit int to 64-bit long") Tested-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: JP Kobryn <inwardvessel@gmail.com> Link: https://lore.kernel.org/r/20230322194754.185781-3-inwardvessel@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-07bpf: cpumap memory usageYafang Shao
A new helper is introduced to calculate cpumap memory usage. The size of cpu_entries can be dynamically changed when we update or delete a cpumap element, but this patch doesn't include the memory size of cpu_entry yet. We can dynamically calculate the memory usage when we alloc or free a cpu_entry, but it will take extra runtime overhead, so let just put it aside currently. Note that the size of different cpu_entry may be different as well. The result as follows, - before 48: cpumap name count_map flags 0x4 key 4B value 4B max_entries 64 memlock 4096B - after 48: cpumap name count_map flags 0x4 key 4B value 4B max_entries 64 memlock 832B Signed-off-by: Yafang Shao <laoar.shao@gmail.com> Link: https://lore.kernel.org/r/20230305124615.12358-10-laoar.shao@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-02-10net: skbuff: drop the word head from skb cacheJakub Kicinski
skbuff_head_cache is misnamed (perhaps for historical reasons?) because it does not hold heads. Head is the buffer which skb->data points to, and also where shinfo lives. struct sk_buff is a metadata structure, not the head. Eric recently added skb_small_head_cache (which allocates actual head buffers), let that serve as an excuse to finally clean this up :) Leave the user-space visible name intact, it could possibly be uAPI. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-11-15bpf: Expand map key argument of bpf_redirect_map to u64Toke Høiland-Jørgensen
For queueing packets in XDP we want to add a new redirect map type with support for 64-bit indexes. To prepare fore this, expand the width of the 'key' argument to the bpf_redirect_map() helper. Since BPF registers are always 64-bit, this should be safe to do after the fact. Acked-by: Song Liu <song@kernel.org> Reviewed-by: Stanislav Fomichev <sdf@google.com> Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://lore.kernel.org/r/20221108140601.149971-3-toke@redhat.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-11-11docs/bpf: Document BPF_MAP_TYPE_CPUMAP mapMaryam Tahhan
Add documentation for BPF_MAP_TYPE_CPUMAP including kernel version introduced, usage and examples. Co-developed-by: Lorenzo Bianconi <lorenzo@kernel.org> Signed-off-by: Maryam Tahhan <mtahhan@redhat.com> Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20221107165207.2682075-2-mtahhan@redhat.com
2022-10-28bpf: check max_entries before allocating memoryFlorian Lehner
For maps of type BPF_MAP_TYPE_CPUMAP memory is allocated first before checking the max_entries argument. If then max_entries is greater than NR_CPUS additional work needs to be done to free allocated memory before an error is returned. This changes moves the check on max_entries before the allocation happens. Signed-off-by: Florian Lehner <dev@der-flo.net> Link: https://lore.kernel.org/r/20221028183405.59554-1-dev@der-flo.net Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2022-08-10bpf: Use bpf_map_area_alloc consistently on bpf map creationYafang Shao
Let's use the generic helper bpf_map_area_alloc() instead of the open-coded kzalloc helpers in bpf maps creation path. Signed-off-by: Yafang Shao <laoar.shao@gmail.com> Link: https://lore.kernel.org/r/20220810151840.16394-5-laoar.shao@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-08-10bpf: Make __GFP_NOWARN consistent in bpf map creationYafang Shao
Some of the bpf maps are created with __GFP_NOWARN, i.e. arraymap, bloom_filter, bpf_local_storage, bpf_struct_ops, lpm_trie, queue_stack_maps, reuseport_array, stackmap and xskmap, while others are created without __GFP_NOWARN, i.e. cpumap, devmap, hashtab, local_storage, offload, ringbuf and sock_map. But there are not key differences between the creation of these maps. So let make this allocation flag consistent in all bpf maps creation. Then we can use a generic helper to alloc all bpf maps. Signed-off-by: Yafang Shao <laoar.shao@gmail.com> Link: https://lore.kernel.org/r/20220810151840.16394-4-laoar.shao@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-04-26bpf: Compute map_btf_id during build timeMenglong Dong
For now, the field 'map_btf_id' in 'struct bpf_map_ops' for all map types are computed during vmlinux-btf init: btf_parse_vmlinux() -> btf_vmlinux_map_ids_init() It will lookup the btf_type according to the 'map_btf_name' field in 'struct bpf_map_ops'. This process can be done during build time, thanks to Jiri's resolve_btfids. selftest of map_ptr has passed: $96 map_ptr:OK Summary: 1/0 PASSED, 0 SKIPPED, 0 FAILED Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Menglong Dong <imagedong@tencent.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-01-21bpf: generalise tail call map compatibility checkToke Hoiland-Jorgensen
The check for tail call map compatibility ensures that tail calls only happen between maps of the same type. To ensure backwards compatibility for XDP frags we need a similar type of check for cpumap and devmap programs, so move the state from bpf_array_aux into bpf_map, add xdp_has_frags to the check, and apply the same check to cpumap and devmap. Acked-by: John Fastabend <john.fastabend@gmail.com> Co-developed-by: Lorenzo Bianconi <lorenzo@kernel.org> Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> Signed-off-by: Toke Hoiland-Jorgensen <toke@redhat.com> Link: https://lore.kernel.org/r/f19fd97c0328a39927f3ad03e1ca6b43fd53cdfd.1642758637.git.lorenzo@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-01-05xdp: Move conversion to xdp_frame out of map functionsToke Høiland-Jørgensen
All map redirect functions except XSK maps convert xdp_buff to xdp_frame before enqueueing it. So move this conversion of out the map functions and into xdp_do_redirect(). This removes a bit of duplicated code, but more importantly it makes it possible to support caller-allocated xdp_frame structures, which will be added in a subsequent commit. Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20220103150812.87914-5-toke@redhat.com
2021-12-13bpf: Let bpf_warn_invalid_xdp_action() report more infoPaolo Abeni
In non trivial scenarios, the action id alone is not sufficient to identify the program causing the warning. Before the previous patch, the generated stack-trace pointed out at least the involved device driver. Let's additionally include the program name and id, and the relevant device name. If the user needs additional infos, he can fetch them via a kernel probe, leveraging the arguments added here. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://lore.kernel.org/bpf/ddb96bb975cbfddb1546cf5da60e77d5100b533c.1638189075.git.pabeni@redhat.com
2021-07-07bpf: cpumap: Implement generic cpumapKumar Kartikeya Dwivedi
This change implements CPUMAP redirect support for generic XDP programs. The idea is to reuse the cpu map entry's queue that is used to push native xdp frames for redirecting skb to a different CPU. This will match native XDP behavior (in that RPS is invoked again for packet reinjected into networking stack). To be able to determine whether the incoming skb is from the driver or cpumap, we reuse skb->redirected bit that skips generic XDP processing when it is set. To always make use of this, CONFIG_NET_REDIRECT guard on it has been lifted and it is always available. >From the redirect side, we add the skb to ptr_ring with its lowest bit set to 1. This should be safe as skb is not 1-byte aligned. This allows kthread to discern between xdp_frames and sk_buff. On consumption of the ptr_ring item, the lowest bit is unset. In the end, the skb is simply added to the list that kthread is anyway going to maintain for xdp_frames converted to skb, and then received again by using netif_receive_skb_list. Bulking optimization for generic cpumap is left as an exercise for a future patch for now. Since cpumap entry progs are now supported, also remove check in generic_xdp_install for the cpumap. Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Link: https://lore.kernel.org/bpf/20210702111825.491065-4-memxor@gmail.com
2021-06-24xdp: Add proper __rcu annotations to redirect map entriesToke Høiland-Jørgensen
XDP_REDIRECT works by a three-step process: the bpf_redirect() and bpf_redirect_map() helpers will lookup the target of the redirect and store it (along with some other metadata) in a per-CPU struct bpf_redirect_info. Next, when the program returns the XDP_REDIRECT return code, the driver will call xdp_do_redirect() which will use the information thus stored to actually enqueue the frame into a bulk queue structure (that differs slightly by map type, but shares the same principle). Finally, before exiting its NAPI poll loop, the driver will call xdp_do_flush(), which will flush all the different bulk queues, thus completing the redirect. Pointers to the map entries will be kept around for this whole sequence of steps, protected by RCU. However, there is no top-level rcu_read_lock() in the core code; instead drivers add their own rcu_read_lock() around the XDP portions of the code, but somewhat inconsistently as Martin discovered[0]. However, things still work because everything happens inside a single NAPI poll sequence, which means it's between a pair of calls to local_bh_disable()/local_bh_enable(). So Paul suggested[1] that we could document this intention by using rcu_dereference_check() with rcu_read_lock_bh_held() as a second parameter, thus allowing sparse and lockdep to verify that everything is done correctly. This patch does just that: we add an __rcu annotation to the map entry pointers and remove the various comments explaining the NAPI poll assurance strewn through devmap.c in favour of a longer explanation in filter.c. The goal is to have one coherent documentation of the entire flow, and rely on the RCU annotations as a "standard" way of communicating the flow in the map code (which can additionally be understood by sparse and lockdep). The RCU annotation replacements result in a fairly straight-forward replacement where READ_ONCE() becomes rcu_dereference_check(), WRITE_ONCE() becomes rcu_assign_pointer() and xchg() and cmpxchg() gets wrapped in the proper constructs to cast the pointer back and forth between __rcu and __kernel address space (for the benefit of sparse). The one complication is that xskmap has a few constructions where double-pointers are passed back and forth; these simply all gain __rcu annotations, and only the final reference/dereference to the inner-most pointer gets changed. With this, everything can be run through sparse without eliciting complaints, and lockdep can verify correctness even without the use of rcu_read_lock() in the drivers. Subsequent patches will clean these up from the drivers. [0] https://lore.kernel.org/bpf/20210415173551.7ma4slcbqeyiba2r@kafai-mbp.dhcp.thefacebook.com/ [1] https://lore.kernel.org/bpf/20210419165837.GA975577@paulmck-ThinkPad-P17-Gen-1/ Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20210624160609.292325-6-toke@redhat.com
2021-05-26xdp: Extend xdp_redirect_map with broadcast supportHangbin Liu
This patch adds two flags BPF_F_BROADCAST and BPF_F_EXCLUDE_INGRESS to extend xdp_redirect_map for broadcast support. With BPF_F_BROADCAST the packet will be broadcasted to all the interfaces in the map. with BPF_F_EXCLUDE_INGRESS the ingress interface will be excluded when do broadcasting. When getting the devices in dev hash map via dev_map_hash_get_next_key(), there is a possibility that we fall back to the first key when a device was removed. This will duplicate packets on some interfaces. So just walk the whole buckets to avoid this issue. For dev array map, we also walk the whole map to find valid interfaces. Function bpf_clear_redirect_map() was removed in commit ee75aef23afe ("bpf, xdp: Restructure redirect actions"). Add it back as we need to use ri->map again. With test topology: +-------------------+ +-------------------+ | Host A (i40e 10G) | ---------- | eno1(i40e 10G) | +-------------------+ | | | Host B | +-------------------+ | | | Host C (i40e 10G) | ---------- | eno2(i40e 10G) | +-------------------+ | | | +------+ | | veth0 -- | Peer | | | veth1 -- | | | | veth2 -- | NS | | | +------+ | +-------------------+ On Host A: # pktgen/pktgen_sample03_burst_single_flow.sh -i eno1 -d $dst_ip -m $dst_mac -s 64 On Host B(Intel(R) Xeon(R) CPU E5-2690 v3 @ 2.60GHz, 128G Memory): Use xdp_redirect_map and xdp_redirect_map_multi in samples/bpf for testing. All the veth peers in the NS have a XDP_DROP program loaded. The forward_map max_entries in xdp_redirect_map_multi is modify to 4. Testing the performance impact on the regular xdp_redirect path with and without patch (to check impact of additional check for broadcast mode): 5.12 rc4 | redirect_map i40e->i40e | 2.0M | 9.7M 5.12 rc4 | redirect_map i40e->veth | 1.7M | 11.8M 5.12 rc4 + patch | redirect_map i40e->i40e | 2.0M | 9.6M 5.12 rc4 + patch | redirect_map i40e->veth | 1.7M | 11.7M Testing the performance when cloning packets with the redirect_map_multi test, using a redirect map size of 4, filled with 1-3 devices: 5.12 rc4 + patch | redirect_map multi i40e->veth (x1) | 1.7M | 11.4M 5.12 rc4 + patch | redirect_map multi i40e->veth (x2) | 1.1M | 4.3M 5.12 rc4 + patch | redirect_map multi i40e->veth (x3) | 0.8M | 2.6M Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Toke Høiland-Jørgensen <toke@redhat.com> Acked-by: Martin KaFai Lau <kafai@fb.com> Acked-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Link: https://lore.kernel.org/bpf/20210519090747.1655268-3-liuhangbin@gmail.com
2021-04-27bpf, cpumap: Bulk skb using netif_receive_skb_listLorenzo Bianconi
Rely on netif_receive_skb_list routine to send skbs converted from xdp_frames in cpu_map_kthread_run in order to improve i-cache usage. The proposed patch has been tested running xdp_redirect_cpu bpf sample available in the kernel tree that is used to redirect UDP frames from ixgbe driver to a cpumap entry and then to the networking stack. UDP frames are generated using pktgen. Packets are discarded by the UDP layer. $ xdp_redirect_cpu --cpu <cpu> --progname xdp_cpu_map0 --dev <eth> bpf-next: ~2.35Mpps bpf-next + cpumap skb-list: ~2.72Mpps Rename drops counter in kmem_alloc_drops since now it reports just kmem_cache_alloc_bulk failures Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Link: https://lore.kernel.org/bpf/c729f83e5d7482d9329e0f165bdbe5adcefd1510.1619169700.git.lorenzo@kernel.org
2021-03-10bpf, xdp: Restructure redirect actionsBjörn Töpel
The XDP_REDIRECT implementations for maps and non-maps are fairly similar, but obviously need to take different code paths depending on if the target is using a map or not. Today, the redirect targets for XDP either uses a map, or is based on ifindex. Here, the map type and id are added to bpf_redirect_info, instead of the actual map. Map type, map item/ifindex, and the map_id (if any) is passed to xdp_do_redirect(). For ifindex-based redirect, used by the bpf_redirect() XDP BFP helper, a special map type/id are used. Map type of UNSPEC together with map id equal to INT_MAX has the special meaning of an ifindex based redirect. Note that valid map ids are 1 inclusive, INT_MAX exclusive ([1,INT_MAX[). In addition to making the code easier to follow, using explicit type and id in bpf_redirect_info has a slight positive performance impact by avoiding a pointer indirection for the map type lookup, and instead use the cacheline for bpf_redirect_info. Since the actual map is not passed via bpf_redirect_info anymore, the map lookup is only done in the BPF helper. This means that the bpf_clear_redirect_map() function can be removed. The actual map item is RCU protected. The bpf_redirect_info flags member is not used by XDP, and not read/written any more. The map member is only written to when required/used, and not unconditionally. Signed-off-by: Björn Töpel <bjorn.topel@intel.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Acked-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://lore.kernel.org/bpf/20210308112907.559576-3-bjorn.topel@gmail.com
2021-03-10bpf, xdp: Make bpf_redirect_map() a map operationBjörn Töpel
Currently the bpf_redirect_map() implementation dispatches to the correct map-lookup function via a switch-statement. To avoid the dispatching, this change adds bpf_redirect_map() as a map operation. Each map provides its bpf_redirect_map() version, and correct function is automatically selected by the BPF verifier. A nice side-effect of the code movement is that the map lookup functions are now local to the map implementation files, which removes one additional function call. Signed-off-by: Björn Töpel <bjorn.topel@intel.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Acked-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://lore.kernel.org/bpf/20210308112907.559576-2-bjorn.topel@gmail.com
2021-01-20net, xdp: Introduce __xdp_build_skb_from_frame utility routineLorenzo Bianconi
Introduce __xdp_build_skb_from_frame utility routine to build the skb from xdp_frame. Rely on __xdp_build_skb_from_frame in cpumap code. Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Link: https://lore.kernel.org/bpf/4f9f4c6b3dd3933770c617eb6689dbc0c6e25863.1610475660.git.lorenzo@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2020-12-02bpf: Eliminate rlimit-based memory accounting for cpumap mapsRoman Gushchin
Do not use rlimit-based memory accounting for cpumap maps. It has been replaced with the memcg-based memory accounting. Signed-off-by: Roman Gushchin <guro@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20201201215900.3569844-21-guro@fb.com
2020-12-02bpf: Refine memcg-based memory accounting for cpumap mapsRoman Gushchin
Include metadata and percpu data into the memcg-based memory accounting. Signed-off-by: Roman Gushchin <guro@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20201201215900.3569844-10-guro@fb.com
2020-09-28bpf, cpumap: Remove rcpu pointer from cpu_map_build_skb signatureLorenzo Bianconi
Get rid of bpf_cpu_map_entry pointer in cpu_map_build_skb routine signature since it is no longer needed. Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/33cb9b7dc447de3ea6fd6ce713ac41bca8794423.1601292015.git.lorenzo@kernel.org
2020-09-04Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
We got slightly different patches removing a double word in a comment in net/ipv4/raw.c - picked the version from net. Simple conflict in drivers/net/ethernet/ibm/ibmvnic.c. Use cached values instead of VNIC login response buffer (following what commit 507ebe6444a4 ("ibmvnic: Fix use-after-free of VNIC login response buffer") did). Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-09-01bpf: {cpu,dev}map: Change various functions return type from int to voidBjörn Töpel
The functions bq_enqueue(), bq_flush_to_queue(), and bq_xmit_all() in {cpu,dev}map.c always return zero. Changing the return type from int to void makes the code easier to follow. Suggested-by: David Ahern <dsahern@gmail.com> Signed-off-by: Björn Töpel <bjorn.topel@intel.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Acked-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://lore.kernel.org/bpf/20200901083928.6199-1-bjorn.topel@gmail.com
2020-08-28bpf: Add map_meta_equal map opsMartin KaFai Lau
Some properties of the inner map is used in the verification time. When an inner map is inserted to an outer map at runtime, bpf_map_meta_equal() is currently used to ensure those properties of the inserting inner map stays the same as the verification time. In particular, the current bpf_map_meta_equal() checks max_entries which turns out to be too restrictive for most of the maps which do not use max_entries during the verification time. It limits the use case that wants to replace a smaller inner map with a larger inner map. There are some maps do use max_entries during verification though. For example, the map_gen_lookup in array_map_ops uses the max_entries to generate the inline lookup code. To accommodate differences between maps, the map_meta_equal is added to bpf_map_ops. Each map-type can decide what to check when its map is used as an inner map during runtime. Also, some map types cannot be used as an inner map and they are currently black listed in bpf_map_meta_alloc() in map_in_map.c. It is not unusual that the new map types may not aware that such blacklist exists. This patch enforces an explicit opt-in and only allows a map to be used as an inner map if it has implemented the map_meta_equal ops. It is based on the discussion in [1]. All maps that support inner map has its map_meta_equal points to bpf_map_meta_equal in this patch. A later patch will relax the max_entries check for most maps. bpf_types.h counts 28 map types. This patch adds 23 ".map_meta_equal" by using coccinelle. -5 for BPF_MAP_TYPE_PROG_ARRAY BPF_MAP_TYPE_(PERCPU)_CGROUP_STORAGE BPF_MAP_TYPE_STRUCT_OPS BPF_MAP_TYPE_ARRAY_OF_MAPS BPF_MAP_TYPE_HASH_OF_MAPS The "if (inner_map->inner_map_meta)" check in bpf_map_meta_alloc() is moved such that the same error is returned. [1]: https://lore.kernel.org/bpf/20200522022342.899756-1-kafai@fb.com/ Signed-off-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20200828011806.1970400-1-kafai@fb.com
2020-08-23treewide: Use fallthrough pseudo-keywordGustavo A. R. Silva
Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-07-21bpf: cpumap: Fix possible rcpu kthread hungLorenzo Bianconi
Fix the following cpumap kthread hung. The issue is currently occurring when __cpu_map_load_bpf_program fails (e.g if the bpf prog has not BPF_XDP_CPUMAP as expected_attach_type) $./test_progs -n 101 101/1 cpumap_with_progs:OK 101 xdp_cpumap_attach:OK Summary: 1/1 PASSED, 0 SKIPPED, 0 FAILED [ 369.996478] INFO: task cpumap/0/map:7:205 blocked for more than 122 seconds. [ 369.998463] Not tainted 5.8.0-rc4-01472-ge57892f50a07 #212 [ 370.000102] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 370.001918] cpumap/0/map:7 D 0 205 2 0x00004000 [ 370.003228] Call Trace: [ 370.003930] __schedule+0x5c7/0xf50 [ 370.004901] ? io_schedule_timeout+0xb0/0xb0 [ 370.005934] ? static_obj+0x31/0x80 [ 370.006788] ? mark_held_locks+0x24/0x90 [ 370.007752] ? cpu_map_bpf_prog_run_xdp+0x6c0/0x6c0 [ 370.008930] schedule+0x6f/0x160 [ 370.009728] schedule_preempt_disabled+0x14/0x20 [ 370.010829] kthread+0x17b/0x240 [ 370.011433] ? kthread_create_worker_on_cpu+0xd0/0xd0 [ 370.011944] ret_from_fork+0x1f/0x30 [ 370.012348] Showing all locks held in the system: [ 370.013025] 1 lock held by khungtaskd/33: [ 370.013432] #0: ffffffff82b24720 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x28/0x1c3 [ 370.014461] ============================================= Fixes: 9216477449f3 ("bpf: cpumap: Add the possibility to attach an eBPF program to cpumap") Reported-by: Jakub Sitnicki <jakub@cloudflare.com> Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Tested-by: Jakub Sitnicki <jakub@cloudflare.com> Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/bpf/e54f2aabf959f298939e5507b09c48f8c2e380be.1595170625.git.lorenzo@kernel.org
2020-07-16bpf: cpumap: Implement XDP_REDIRECT for eBPF programs attached to map entriesLorenzo Bianconi
Introduce XDP_REDIRECT support for eBPF programs attached to cpumap entries. This patch has been tested on Marvell ESPRESSObin using a modified version of xdp_redirect_cpu sample in order to attach a XDP program to CPUMAP entries to perform a redirect on the mvneta interface. In particular the following scenario has been tested: rq (cpu0) --> mvneta - XDP_REDIRECT (cpu0) --> CPUMAP - XDP_REDIRECT (cpu1) --> mvneta $./xdp_redirect_cpu -p xdp_cpu_map0 -d eth0 -c 1 -e xdp_redirect \ -f xdp_redirect_kern.o -m tx_port -r eth0 tx: 285.2 Kpps rx: 285.2 Kpps Attaching a simple XDP program on eth0 to perform XDP_TX gives comparable results: tx: 288.4 Kpps rx: 288.4 Kpps Co-developed-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Link: https://lore.kernel.org/bpf/2cf8373a731867af302b00c4ff16c122630c4980.1594734381.git.lorenzo@kernel.org
2020-07-16bpf: cpumap: Add the possibility to attach an eBPF program to cpumapLorenzo Bianconi
Introduce the capability to attach an eBPF program to cpumap entries. The idea behind this feature is to add the possibility to define on which CPU run the eBPF program if the underlying hw does not support RSS. Current supported verdicts are XDP_DROP and XDP_PASS. This patch has been tested on Marvell ESPRESSObin using xdp_redirect_cpu sample available in the kernel tree to identify possible performance regressions. Results show there are no observable differences in packet-per-second: $./xdp_redirect_cpu --progname xdp_cpu_map0 --dev eth0 --cpu 1 rx: 354.8 Kpps rx: 356.0 Kpps rx: 356.8 Kpps rx: 356.3 Kpps rx: 356.6 Kpps rx: 356.6 Kpps rx: 356.7 Kpps rx: 355.8 Kpps rx: 356.8 Kpps rx: 356.8 Kpps Co-developed-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Link: https://lore.kernel.org/bpf/5c9febdf903d810b3415732e5cd98491d7d9067a.1594734381.git.lorenzo@kernel.org
2020-07-16cpumap: Formalize map value as a named structLorenzo Bianconi
As it has been already done for devmap, introduce 'struct bpf_cpumap_val' to formalize the expected values that can be passed in for a CPUMAP. Update cpumap code to use the struct. Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Link: https://lore.kernel.org/bpf/754f950674665dae6139c061d28c1d982aaf4170.1594734381.git.lorenzo@kernel.org
2020-07-16cpumap: Use non-locked version __ptr_ring_consume_batchedJesper Dangaard Brouer
Commit 77361825bb01 ("bpf: cpumap use ptr_ring_consume_batched") changed away from using single frame ptr_ring dequeue (__ptr_ring_consume) to consume a batched, but it uses a locked version, which as the comment explain isn't needed. Change to use the non-locked version __ptr_ring_consume_batched. Fixes: 77361825bb01 ("bpf: cpumap use ptr_ring_consume_batched") Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/a9c7d06f9a009e282209f0c8c7b2c5d9b9ad60b9.1594734381.git.lorenzo@kernel.org
2020-06-22bpf: Set map_btf_{name, id} for all map typesAndrey Ignatov
Set map_btf_name and map_btf_id for all map types so that map fields can be accessed by bpf programs. Signed-off-by: Andrey Ignatov <rdna@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/bpf/a825f808f22af52b018dbe82f1c7d29dab5fc978.1592600985.git.rdna@fb.com
generated by cgit (git 2.34.1) at 2025-07-26 00:25:55 +0000