- 21 Jul, 2020 5 commits
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Ilya Leoshkevich authored
"BPF_MAXINSNS: Maximum possible literals" test causes panic with bpf_jit_harden = 2. The reason is that BPF_JMP | BPF_EXIT is always emitted as brc, however, after removal of JITed image size limitations, brcl might be required. Fix by using brcl when necessary. Fixes: 4e9b4a68 ("s390/bpf: Use relative long branches") Signed-off-by:
Ilya Leoshkevich <iii@linux.ibm.com> Signed-off-by:
Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200717165326.6786-4-iii@linux.ibm.com
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Ilya Leoshkevich authored
Both signed and unsigned variants of BPF_JMP | BPF_K require sign-extending the immediate. JIT emits cgfi for the signed case, which is correct, and clgfi for the unsigned case, which is not correct: clgfi zero-extends the immediate. s390 does not provide an instruction that does sign-extension and unsigned comparison at the same time. Therefore, fix by first loading the sign-extended immediate into work register REG_1 and proceeding as if it's BPF_X. Fixes: 4e9b4a68 ("s390/bpf: Use relative long branches") Reported-by:
Seth Forshee <seth.forshee@canonical.com> Signed-off-by:
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Ilya Leoshkevich authored
When running out of srctree, relative path to lib/test_bpf.ko is different than when running in srctree. Check $building_out_of_srctree environment variable and use a different relative path if needed. Signed-off-by:
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Lorenzo Bianconi authored
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-ge57892f5 #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: 92164774 ("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:
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Jakub Sitnicki authored
When CONFIG_NET is set but CONFIG_INET isn't, build fails with: ld: kernel/bpf/net_namespace.o: in function `netns_bpf_attach_type_unneed': kernel/bpf/net_namespace.c:32: undefined reference to `bpf_sk_lookup_enabled' ld: kernel/bpf/net_namespace.o: in function `netns_bpf_attach_type_need': kernel/bpf/net_namespace.c:43: undefined reference to `bpf_sk_lookup_enabled' This is because without CONFIG_INET bpf_sk_lookup_enabled symbol is not available. Wrap references to bpf_sk_lookup_enabled with preprocessor conditionals. Fixes: 1559b4aa ("inet: Run SK_LOOKUP BPF program on socket lookup") Reported-by:
Randy Dunlap <rdunlap@infradead.org> Reported-by:
Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by:
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- 18 Jul, 2020 16 commits
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Alexei Starovoitov authored
Jakub Sitnicki says: ==================== Changelog ========= v4 -> v5: - Enforce BPF prog return value to be SK_DROP or SK_PASS. (Andrii) - Simplify prog runners now that only SK_DROP/PASS can be returned. - Enable bpf_perf_event_output from the start. (Andrii) - Drop patch "selftests/bpf: Rename test_sk_lookup_kern.c to test_ref_track_kern.c" - Remove tests for narrow loads from context at an offset wider in size than target field, while we are discussing how to fix it: https://lore.kernel.org/bpf/20200710173123.427983-1-jakub@cloudflare.com/ - Rebase onto recent bpf-next (bfdfa517) - Other minor changes called out in per-patch changelogs, see patches: 2, 4, 6, 13-15 - Carried over Andrii's Acks where nothing changed. v3 -> v4: - Reduce BPF prog return codes to SK_DROP/SK_PASS (Lorenz) - Default to drop on illegal return value from BPF prog (Lorenz) - Extend bpf_sk_assign to accept NULL socket pointer. - Switch to saner return values and add docs for new prog_array API (Andrii) - Add support for narrow loads from BPF context fields (Yonghong) - Fix broken build when IPv6 is compiled as a module (kernel test robot) - Fix null/wild-ptr-deref on BPF context access - Rebase to recent bpf-next (eef8a42d) - Other minor changes called out in per-patch changelogs, see patches 1-2, 4, 6, 8, 10-12, 14, 16 v2 -> v3: - Switch to link-based program attachment - Support for multi-prog attachment - Ability to skip reuseport socket selection - Code on RX path is guarded by a static key - struct in6_addr's are no longer copied into BPF prog context - BPF prog context is initialized as late as possible - Changes called out in patches 1-2, 4, 6, 8, 10-14, 16 - Patches dropped: 01/17 flow_dissector: Extract attach/detach/query helpers 03/17 inet: Store layer 4 protocol in inet_hashinfo 08/17 udp: Store layer 4 protocol in udp_table v1 -> v2: - Changes called out in patches 2, 13-15, 17 - Rebase to recent bpf-next (b4563fac) RFCv2 -> v1: - Switch to fetching a socket from a map and selecting a socket with bpf_sk_assign, instead of having a dedicated helper that does both. - Run reuseport logic on sockets selected by BPF sk_lookup. - Allow BPF sk_lookup to fail the lookup with no match. - Go back to having just 2 hash table lookups in UDP. RFCv1 -> RFCv2: - Make socket lookup redirection map-based. BPF program now uses a dedicated helper and a SOCKARRAY map to select the socket to redirect to. A consequence of this change is that bpf_inet_lookup context is now read-only. - Look for connected UDP sockets before allowing redirection from BPF. This makes connected UDP socket work as expected in the presence of inet_lookup prog. - Share the code for BPF_PROG_{ATTACH,DETACH,QUERY} with flow_dissector, the only other per-netns BPF prog type. Overview ======== This series proposes a new BPF program type named BPF_PROG_TYPE_SK_LOOKUP, or BPF sk_lookup for short. BPF sk_lookup program runs when transport layer is looking up a listening socket for a new connection request (TCP), or when looking up an unconnected socket for a packet (UDP). This serves as a mechanism to overcome the limits of what bind() API allows to express. Two use-cases driving this work are: (1) steer packets destined to an IP range, fixed port to a single socket 192.0.2.0/24, port 80 -> NGINX socket (2) steer packets destined to an IP address, any port to a single socket 198.51.100.1, any port -> L7 proxy socket In its context, program receives information about the packet that triggered the socket lookup. Namely IP version, L4 protocol identifier, and address 4-tuple. To select a socket BPF program fetches it from a map holding socket references, like SOCKMAP or SOCKHASH, calls bpf_sk_assign(ctx, sk, ...) helper to record the selection, and returns SK_PASS code. Transport layer then uses the selected socket as a result of socket lookup. Alternatively, program can also fail the lookup (SK_DROP), or let the lookup continue as usual (SK_PASS without selecting a socket). This lets the user match packets with listening (TCP) or receiving (UDP) sockets freely at the last possible point on the receive path, where we know that packets are destined for local delivery after undergoing policing, filtering, and routing. Program is attached to a network namespace, similar to BPF flow_dissector. We add a new attach type, BPF_SK_LOOKUP, for this. Multiple programs can be attached at the same time, in which case their return values are aggregated according the rules outlined in patch #4 description. Series structure ================ Patches are organized as so: 1: enables multiple link-based prog attachments for bpf-netns 2: introduces sk_lookup program type 3-4: hook up the program to run on ipv4/tcp socket lookup 5-6: hook up the program to run on ipv6/tcp socket lookup 7-8: hook up the program to run on ipv4/udp socket lookup 9-10: hook up the program to run on ipv6/udp socket lookup 11-13: libbpf & bpftool support for sk_lookup 14-15: verifier and selftests for sk_lookup Patches are also available on GH: https://github.com/jsitnicki/linux/commits/bpf-inet-lookup-v5 Follow-up work ============== I'll follow up with below items, which IMHO don't block the review: - benchmark results for udp6 small packet flood scenario, - user docs for new BPF prog type, Documentation/bpf/prog_sk_lookup.rst, - timeout for accept() in tests after extending network_helper.[ch]. Thanks to the reviewers for their feedback to this patch series: Cc: Alexei Starovoitov <ast@kernel.org> Cc: Andrii Nakryiko <andriin@fb.com> Cc: Lorenz Bauer <lmb@cloudflare.com> Cc: Marek Majkowski <marek@cloudflare.com> Cc: Martin KaFai Lau <kafai@fb.com> Cc: Yonghong Song <yhs@fb.com> -jkbs [RFCv1] https://lore.kernel.org/bpf/20190618130050.8344-1-jakub@cloudflare.com/ [RFCv2] https://lore.kernel.org/bpf/20190828072250.29828-1-jakub@cloudflare.com/ [v1] https://lore.kernel.org/bpf/20200511185218.1422406-18-jakub@cloudflare.com/ [v2] https://lore.kernel.org/bpf/20200506125514.1020829-1-jakub@cloudflare.com/ [v3] https://lore.kernel.org/bpf/20200702092416.11961-1-jakub@cloudflare.com/ [v4] https://lore.kernel.org/bpf/20200713174654.642628-1-jakub@cloudflare.com/ ==================== Reviewed-by:
Lorenz Bauer <lmb@cloudflare.com> Signed-off-by:
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Jakub Sitnicki authored
Add tests to test_progs that exercise: - attaching/detaching/querying programs to BPF_SK_LOOKUP hook, - redirecting socket lookup to a socket selected by BPF program, - failing a socket lookup on BPF program's request, - error scenarios for selecting a socket from BPF program, - accessing BPF program context, - attaching and running multiple BPF programs. Run log: bash-5.0# ./test_progs -n 70 #70/1 query lookup prog:OK #70/2 TCP IPv4 redir port:OK #70/3 TCP IPv4 redir addr:OK #70/4 TCP IPv4 redir with reuseport:OK #70/5 TCP IPv4 redir skip reuseport:OK #70/6 TCP IPv6 redir port:OK #70/7 TCP IPv6 redir addr:OK #70/8 TCP IPv4->IPv6 redir port:OK #70/9 TCP IPv6 redir with reuseport:OK #70/10 TCP IPv6 redir skip reuseport:OK #70/11 UDP IPv4 redir port:OK #70/12 UDP IPv4 redir addr:OK #70/13 UDP IPv4 redir with reuseport:OK #70/14 UDP IPv4 redir skip reuseport:OK #70/15 UDP IPv6 redir port:OK #70/16 UDP IPv6 redir addr:OK #70/17 UDP IPv4->IPv6 redir port:OK #70/18 UDP IPv6 redir and reuseport:OK #70/19 UDP IPv6 redir skip reuseport:OK #70/20 TCP IPv4 drop on lookup:OK #70/21 TCP IPv6 drop on lookup:OK #70/22 UDP IPv4 drop on lookup:OK #70/23 UDP IPv6 drop on lookup:OK #70/24 TCP IPv4 drop on reuseport:OK #70/25 TCP IPv6 drop on reuseport:OK #70/26 UDP IPv4 drop on reuseport:OK #70/27 TCP IPv6 drop on reuseport:OK #70/28 sk_assign returns EEXIST:OK #70/29 sk_assign honors F_REPLACE:OK #70/30 sk_assign accepts NULL socket:OK #70/31 access ctx->sk:OK #70/32 narrow access to ctx v4:OK #70/33 narrow access to ctx v6:OK #70/34 sk_assign rejects TCP established:OK #70/35 sk_assign rejects UDP connected:OK #70/36 multi prog - pass, pass:OK #70/37 multi prog - drop, drop:OK #70/38 multi prog - pass, drop:OK #70/39 multi prog - drop, pass:OK #70/40 multi prog - pass, redir:OK #70/41 multi prog - redir, pass:OK #70/42 multi prog - drop, redir:OK #70/43 multi prog - redir, drop:OK #70/44 multi prog - redir, redir:OK #70 sk_lookup:OK Summary: 1/44 PASSED, 0 SKIPPED, 0 FAILED Signed-off-by:
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Jakub Sitnicki authored
Exercise verifier access checks for bpf_sk_lookup context fields. Signed-off-by:
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Jakub Sitnicki authored
Make bpftool show human-friendly identifiers for newly introduced program and attach type, BPF_PROG_TYPE_SK_LOOKUP and BPF_SK_LOOKUP, respectively. Also, add the new prog type bash-completion, man page and help message. Signed-off-by:
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Jakub Sitnicki authored
Make libbpf aware of the newly added program type, and assign it a section name. Signed-off-by:
Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200717103536.397595-13-jakub@cloudflare.com
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Jakub Sitnicki authored
Newly added program, context type and helper is used by tests in a subsequent patch. Synchronize the header file. Signed-off-by:
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Jakub Sitnicki authored
Same as for udp4, let BPF program override the socket lookup result, by selecting a receiving socket of its choice or failing the lookup, if no connected UDP socket matched packet 4-tuple. Suggested-by:
Marek Majkowski <marek@cloudflare.com> Signed-off-by:
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Jakub Sitnicki authored
Prepare for calling into reuseport from __udp6_lib_lookup as well. Signed-off-by:
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Jakub Sitnicki authored
Following INET/TCP socket lookup changes, modify UDP socket lookup to let BPF program select a receiving socket before searching for a socket by destination address and port as usual. Lookup of connected sockets that match packet 4-tuple is unaffected by this change. BPF program runs, and potentially overrides the lookup result, only if a 4-tuple match was not found. Suggested-by:
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Jakub Sitnicki authored
Prepare for calling into reuseport from __udp4_lib_lookup as well. Signed-off-by:
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Jakub Sitnicki authored
Following ipv4 stack changes, run a BPF program attached to netns before looking up a listening socket. Program can return a listening socket to use as result of socket lookup, fail the lookup, or take no action. Suggested-by:
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Jakub Sitnicki authored
Prepare for calling into reuseport from inet6_lookup_listener as well. Signed-off-by:
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Jakub Sitnicki authored
Run a BPF program before looking up a listening socket on the receive path. Program selects a listening socket to yield as result of socket lookup by calling bpf_sk_assign() helper and returning SK_PASS code. Program can revert its decision by assigning a NULL socket with bpf_sk_assign(). Alternatively, BPF program can also fail the lookup by returning with SK_DROP, or let the lookup continue as usual with SK_PASS on return, when no socket has been selected with bpf_sk_assign(). This lets the user match packets with listening sockets freely at the last possible point on the receive path, where we know that packets are destined for local delivery after undergoing policing, filtering, and routing. With BPF code selecting the socket, directing packets destined to an IP range or to a port range to a single socket becomes possible. In case multiple programs are attached, they are run in series in the order in which they were attached. The end result is determined from return codes of all the programs according to following rules: 1. If any program returned SK_PASS and selected a valid socket, the socket is used as result of socket lookup. 2. If more than one program returned SK_PASS and selected a socket, last selection takes effect. 3. If any program returned SK_DROP, and no program returned SK_PASS and selected a socket, socket lookup fails with -ECONNREFUSED. 4. If all programs returned SK_PASS and none of them selected a socket, socket lookup continues to htable-based lookup. Suggested-by: -
Jakub Sitnicki authored
Prepare for calling into reuseport from __inet_lookup_listener as well. Signed-off-by:
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Jakub Sitnicki authored
Add a new program type BPF_PROG_TYPE_SK_LOOKUP with a dedicated attach type BPF_SK_LOOKUP. The new program kind is to be invoked by the transport layer when looking up a listening socket for a new connection request for connection oriented protocols, or when looking up an unconnected socket for a packet for connection-less protocols. When called, SK_LOOKUP BPF program can select a socket that will receive the packet. This serves as a mechanism to overcome the limits of what bind() API allows to express. Two use-cases driving this work are: (1) steer packets destined to an IP range, on fixed port to a socket 192.0.2.0/24, port 80 -> NGINX socket (2) steer packets destined to an IP address, on any port to a socket 198.51.100.1, any port -> L7 proxy socket In its run-time context program receives information about the packet that triggered the socket lookup. Namely IP version, L4 protocol identifier, and address 4-tuple. Context can be further extended to include ingress interface identifier. To select a socket BPF program fetches it from a map holding socket references, like SOCKMAP or SOCKHASH, and calls bpf_sk_assign(ctx, sk, ...) helper to record the selection. Transport layer then uses the selected socket as a result of socket lookup. In its basic form, SK_LOOKUP acts as a filter and hence must return either SK_PASS or SK_DROP. If the program returns with SK_PASS, transport should look for a socket to receive the packet, or use the one selected by the program if available, while SK_DROP informs the transport layer that the lookup should fail. This patch only enables the user to attach an SK_LOOKUP program to a network namespace. Subsequent patches hook it up to run on local delivery path in ipv4 and ipv6 stacks. Suggested-by: -
Jakub Sitnicki authored
Extend the BPF netns link callbacks to rebuild (grow/shrink) or update the prog_array at given position when link gets attached/updated/released. This let's us lift the limit of having just one link attached for the new attach type introduced by subsequent patch. No functional changes intended. Signed-off-by:
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- 16 Jul, 2020 19 commits
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Randy Dunlap authored
Drop doubled words "will" and "attach". Signed-off-by:
Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/6b9f71ae-4f8e-0259-2c5d-187ddaefe6eb@infradead.org
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Stanislav Fomichev authored
Andrii reported that sockopt_inherit occasionally hangs up on 5.5 kernel [0]. This can happen if server_thread runs faster than the main thread. In that case, pthread_cond_wait will wait forever because pthread_cond_signal was executed before the main thread was blocking. Let's move pthread_mutex_lock up a bit to make sure server_thread runs strictly after the main thread goes to sleep. (Not sure why this is 5.5 specific, maybe scheduling is less deterministic? But I was able to confirm that it does indeed happen in a VM.) [0] https://lore.kernel.org/bpf/CAEf4BzY0-bVNHmCkMFPgObs=isUAyg-dFzGDY7QWYkmm7rmTSg@mail.gmail.com/Reported-by:
Stanislav Fomichev <sdf@google.com> Signed-off-by:
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Seth Forshee authored
This reverts commit 3203c901 ("test_bpf: flag tests that cannot be jited on s390"). The s390 bpf JIT previously had a restriction on the maximum program size, which required some tests in test_bpf to be flagged as expected failures. The program size limitation has been removed, and the tests now pass, so these tests should no longer be flagged. Fixes: d1242b10 ("s390/bpf: Remove JITed image size limitations") Signed-off-by:
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Lorenzo Bianconi authored
Similar to what have been done for DEVMAP, introduce tests to verify ability to add a XDP program to an entry in a CPUMAP. Verify CPUMAP programs can not be attached to devices as a normal XDP program, and only programs with BPF_XDP_CPUMAP attach type can be loaded in a CPUMAP. Signed-off-by:
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Lorenzo Bianconi authored
Extend xdp_redirect_cpu_{usr,kern}.c adding the possibility to load a XDP program on cpumap entries. The following options have been added: - mprog-name: cpumap entry program name - mprog-filename: cpumap entry program filename - redirect-device: output interface if the cpumap program performs a XDP_REDIRECT to an egress interface - redirect-map: bpf map used to perform XDP_REDIRECT to an egress interface - mprog-disable: disable loading XDP program on cpumap entries Add xdp_pass, xdp_drop, xdp_redirect stats accounting Co-developed-by:Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by:
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Lorenzo Bianconi authored
As for DEVMAP, support SEC("xdp_cpumap/") as a short cut for loading the program with type BPF_PROG_TYPE_XDP and expected attach type BPF_XDP_CPUMAP. Signed-off-by: -
Lorenzo Bianconi authored
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:
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Lorenzo Bianconi authored
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:
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Lorenzo Bianconi authored
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:
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Lorenzo Bianconi authored
Do not update xdp_redirect_cpu maps running while option loop but defer it after all available options have been parsed. This is a preliminary patch to pass the program name we want to attach to the map entries as a user option Signed-off-by:
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David Ahern authored
Move the guts of xdp_convert_buff_to_frame to a new helper, xdp_update_frame_from_buff so it can be reused removing code duplication Suggested-by:
David Ahern <dsahern@kernel.org> Signed-off-by:
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Jesper Dangaard Brouer authored
Commit 77361825 ("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: 77361825 ("bpf: cpumap use ptr_ring_consume_batched") Signed-off-by:
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Randy Dunlap authored
Drop the doubled word "by" in a comment. Signed-off-by:
Jakub Kicinski <kuba@kernel.org>
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Randy Dunlap authored
Drop doubled words in several comments. Signed-off-by:
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Randy Dunlap authored
Drop doubled word "the" in a comment. Signed-off-by:
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Randy Dunlap authored
Drop doubled word "to" in a comment. Signed-off-by:
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Randy Dunlap authored
Drop doubled words "or" and "the" in several comments. Signed-off-by:
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Randy Dunlap authored
Drop doubled word "not" in a comment. Signed-off-by:
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Randy Dunlap authored
Drop doubled words in two comments. Fix a spello/typo. Signed-off-by:
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