kernel/git/stable/linux.git/samples/bpf, branch linux-5.16.y

samples/bpf, xdpsock: Fix race when running for fix duration of time

2022-04-08T12:06:17+00:00

[ Upstream commit 8fa42d78f6354bb96ad3a079dcbef528ca9fa9e0 ] When running xdpsock for a fix duration of time before terminating using --duration=, there is a race condition that may cause xdpsock to terminate immediately. When running for a fixed duration of time the check to determine when to terminate execution is in is_benchmark_done() and is being executed in the context of the poller thread, if (opt_duration > 0) { unsigned long dt = (get_nsecs() - start_time); if (dt >= opt_duration) benchmark_done = true; } However start_time is only set after the poller thread have been created. This leaves a small window when the poller thread is starting and calls is_benchmark_done() for the first time that start_time is not yet set. In that case start_time have its initial value of 0 and the duration check fails as it do not correlate correctly for the applications start time and immediately sets benchmark_done which in turn terminates the xdpsock application. Fix this by setting start_time before creating the poller thread. Fixes: d3f11b018f6c ("samples/bpf: xdpsock: Add duration option to specify how long to run") Signed-off-by: Niklas Söderlund Signed-off-by: Simon Horman Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20220315102948.466436-1-niklas.soderlund@corigine.com Signed-off-by: Sasha Levin

samples: bpf: Fix 'unknown warning group' build warning on Clang

2022-01-27T11:01:41+00:00

[ Upstream commit 6f670d06e47c774bc065aaa84a527a4838f34bd8 ] Clang doesn't have 'stringop-truncation' group like GCC does, and complains about it when building samples which use xdp_sample_user infra: samples/bpf/xdp_sample_user.h:48:32: warning: unknown warning group '-Wstringop-truncation', ignored [-Wunknown-warning-option] #pragma GCC diagnostic ignored "-Wstringop-truncation" ^ [ repeat ] Those are harmless, but avoidable when guarding it with ifdef. I could guard push/pop as well, but this would require one more ifdef cruft around a single line which I don't think is reasonable. Fixes: 156f886cf697 ("samples: bpf: Add basic infrastructure for XDP samples") Signed-off-by: Alexander Lobakin Signed-off-by: Andrii Nakryiko Acked-by: Kumar Kartikeya Dwivedi Link: https://lore.kernel.org/bpf/20211203195004.5803-3-alexandr.lobakin@intel.com Signed-off-by: Sasha Levin

samples: bpf: Fix xdp_sample_user.o linking with Clang

2022-01-27T11:01:41+00:00

[ Upstream commit e64fbcaa7a666f16329b1c67af15ea501bc84586 ] Clang (13) doesn't get the jokes about specifying libraries to link in cclags of individual .o objects: clang-13: warning: -lm: 'linker' input unused [-Wunused-command-line-argument] [ ... ] LD samples/bpf/xdp_redirect_cpu LD samples/bpf/xdp_redirect_map_multi LD samples/bpf/xdp_redirect_map LD samples/bpf/xdp_redirect LD samples/bpf/xdp_monitor /usr/bin/ld: samples/bpf/xdp_sample_user.o: in function `sample_summary_print': xdp_sample_user.c:(.text+0x84c): undefined reference to `floor' /usr/bin/ld: xdp_sample_user.c:(.text+0x870): undefined reference to `ceil' /usr/bin/ld: xdp_sample_user.c:(.text+0x8cf): undefined reference to `floor' /usr/bin/ld: xdp_sample_user.c:(.text+0x8f3): undefined reference to `ceil' [ more ] Specify '-lm' as ldflags for all xdp_sample_user.o users in the main Makefile and remove it from ccflags of ^ in Makefile.target -- just like it's done for all other samples. This works with all compilers. Fixes: 6e1051a54e31 ("samples: bpf: Convert xdp_monitor to XDP samples helper") Fixes: b926c55d856c ("samples: bpf: Convert xdp_redirect to XDP samples helper") Fixes: e531a220cc59 ("samples: bpf: Convert xdp_redirect_cpu to XDP samples helper") Fixes: bbe65865aa05 ("samples: bpf: Convert xdp_redirect_map to XDP samples helper") Fixes: 594a116b2aa1 ("samples: bpf: Convert xdp_redirect_map_multi to XDP samples helper") Signed-off-by: Alexander Lobakin Signed-off-by: Andrii Nakryiko Acked-by: Kumar Kartikeya Dwivedi Link: https://lore.kernel.org/bpf/20211203195004.5803-2-alexandr.lobakin@intel.com Signed-off-by: Sasha Levin

samples/bpf: Clean up samples/bpf build failes

2022-01-27T11:01:41+00:00

[ Upstream commit 527024f7aeb683ce7ef49b07ef7ce9ecf015288d ] Remove xdp_samples_user.o rule redefinition which generates Makefile warning and instead override TPROGS_CFLAGS. This seems to work fine when building inside selftests/bpf. That was one big head-scratcher before I found that generic Makefile.target hid this surprising specialization for for xdp_samples_user.o. Main change is to use actual locally installed libbpf headers. Also drop printk macro re-definition (not even used!). Signed-off-by: Andrii Nakryiko Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20211201232824.3166325-8-andrii@kernel.org Signed-off-by: Sasha Levin

samples/bpf: Fix build error due to -isystem removal

2021-11-16T04:37:20+00:00

Since recent Kbuild updates we no longer include files from compiler directories. However, samples/bpf/hbm_kern.h hasn't been tuned for this (LLVM 13): CLANG-bpf samples/bpf/hbm_out_kern.o In file included from samples/bpf/hbm_out_kern.c:55: samples/bpf/hbm_kern.h:12:10: fatal error: 'stddef.h' file not found ^~~~~~~~~~ 1 error generated. CLANG-bpf samples/bpf/hbm_edt_kern.o In file included from samples/bpf/hbm_edt_kern.c:53: samples/bpf/hbm_kern.h:12:10: fatal error: 'stddef.h' file not found ^~~~~~~~~~ 1 error generated. It is enough to just drop both stdbool.h and stddef.h from includes to fix those. Fixes: 04e85bbf71c9 ("isystem: delete global -isystem compile option") Signed-off-by: Alexander Lobakin Signed-off-by: Daniel Borkmann Reviewed-by: Michal Swiatkowski Link: https://lore.kernel.org/bpf/20211115130741.3584-1-alexandr.lobakin@intel.com Signed-off-by: Alexei Starovoitov

samples/bpf: Fix incorrect use of strlen in xdp_redirect_cpu

2021-11-13T01:23:16+00:00

Commit b599015f044d ("samples/bpf: Fix application of sizeof to pointer") tried to fix a bug where sizeof was incorrectly applied to a pointer instead of the array string was being copied to, to find the destination buffer size, but ended up using strlen, which is still incorrect. However, on closer look ifname_buf has no other use, hence directly use optarg. Fixes: b599015f044d ("samples/bpf: Fix application of sizeof to pointer") Fixes: e531a220cc59 ("samples: bpf: Convert xdp_redirect_cpu to XDP samples helper") Signed-off-by: Kumar Kartikeya Dwivedi Signed-off-by: Daniel Borkmann Reviewed-by: Alexander Lobakin Tested-by: Alexander Lobakin Link: https://lore.kernel.org/bpf/20211112020301.528357-1-memxor@gmail.com Signed-off-by: Alexei Starovoitov

samples/bpf: Fix summary per-sec stats in xdp_sample_user

2021-11-13T01:23:16+00:00

sample_summary_print() uses accumulated period to calculate and display per-sec averages. This period gets incremented by sampling interval each time a new sample is formed, and thus equals to the number of samples collected multiplied by this interval. However, the totals are being calculated differently, they receive current sample statistics already divided by the interval gotten as a difference between sample timestamps for better precision -- in other words, they are being incremented by the per-sec values each sample. This leads to the excessive division of summary per-secs when interval != 1 sec. It is obvious pps couldn't become two times lower just from picking a different sampling interval value: $ samples/bpf/xdp_redirect_cpu -p xdp_prognum_n1_inverse_qnum -c all -s -d 6 -i 1 < snip > Packets received : 2,197,230,321 Average packets/s : 22,887,816 Packets redirected : 2,197,230,472 Average redir/s : 22,887,817 $ samples/bpf/xdp_redirect_cpu -p xdp_prognum_n1_inverse_qnum -c all -s -d 6 -i 2 < snip > Packets received : 159,566,498 Average packets/s : 11,397,607 Packets redirected : 159,566,995 Average redir/s : 11,397,642 This can be easily fixed by treating the divisor not as a period, but rather as a total number of samples, and thus incrementing it by 1 instead of interval. As a nice side effect, we can now remove so-named argument from a couple of functions. Let us also create an "alias" for sample_output::rx_cnt::pps named 'num' using a union since this field is used to store this number (period previously) as well, and the resulting counter-intuitive code might've been a reason for this bug. Fixes: 156f886cf697 ("samples: bpf: Add basic infrastructure for XDP samples") Signed-off-by: Alexander Lobakin Signed-off-by: Daniel Borkmann Reviewed-by: Jesse Brandeburg Reviewed-by: Kumar Kartikeya Dwivedi Link: https://lore.kernel.org/bpf/20211111215703.690-1-alexandr.lobakin@intel.com Signed-off-by: Alexei Starovoitov

Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

2021-11-02T02:59:46+00:00

Alexei Starovoitov says: ==================== pull-request: bpf-next 2021-11-01 We've added 181 non-merge commits during the last 28 day(s) which contain a total of 280 files changed, 11791 insertions(+), 5879 deletions(-). The main changes are: 1) Fix bpf verifier propagation of 64-bit bounds, from Alexei. 2) Parallelize bpf test_progs, from Yucong and Andrii. 3) Deprecate various libbpf apis including af_xdp, from Andrii, Hengqi, Magnus. 4) Improve bpf selftests on s390, from Ilya. 5) bloomfilter bpf map type, from Joanne. 6) Big improvements to JIT tests especially on Mips, from Johan. 7) Support kernel module function calls from bpf, from Kumar. 8) Support typeless and weak ksym in light skeleton, from Kumar. 9) Disallow unprivileged bpf by default, from Pawan. 10) BTF_KIND_DECL_TAG support, from Yonghong. 11) Various bpftool cleanups, from Quentin. * https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (181 commits) libbpf: Deprecate AF_XDP support kbuild: Unify options for BTF generation for vmlinux and modules selftests/bpf: Add a testcase for 64-bit bounds propagation issue. bpf: Fix propagation of signed bounds from 64-bit min/max into 32-bit. bpf: Fix propagation of bounds from 64-bit min/max into 32-bit and var_off. selftests/bpf: Fix also no-alu32 strobemeta selftest bpf: Add missing map_delete_elem method to bloom filter map selftests/bpf: Add bloom map success test for userspace calls bpf: Add alignment padding for "map_extra" + consolidate holes bpf: Bloom filter map naming fixups selftests/bpf: Add test cases for struct_ops prog bpf: Add dummy BPF STRUCT_OPS for test purpose bpf: Factor out helpers for ctx access checking bpf: Factor out a helper to prepare trampoline for struct_ops prog selftests, bpf: Fix broken riscv build riscv, libbpf: Add RISC-V (RV64) support to bpf_tracing.h tools, build: Add RISC-V to HOSTARCH parsing riscv, bpf: Increase the maximum number of iterations selftests, bpf: Add one test for sockmap with strparser selftests, bpf: Fix test_txmsg_ingress_parser error ... ==================== Link: https://lore.kernel.org/r/20211102013123.9005-1-alexei.starovoitov@gmail.com Signed-off-by: Jakub Kicinski

samples: bpf: Suppress readelf stderr when probing for BTF support

2021-10-21T22:09:23+00:00

When compiling bpf samples, the following warning appears: readelf: Error: Missing knowledge of 32-bit reloc types used in DWARF sections of machine number 247 readelf: Warning: unable to apply unsupported reloc type 10 to section .debug_info readelf: Warning: unable to apply unsupported reloc type 1 to section .debug_info readelf: Warning: unable to apply unsupported reloc type 10 to section .debug_info Same problem was mentioned in commit 2f0921262ba9 ("selftests/bpf: suppress readelf stderr when probing for BTF support"), let's use readelf that supports btf. Signed-off-by: Pu Lehui Signed-off-by: Alexei Starovoitov Acked-by: John Fastabend Link: https://lore.kernel.org/bpf/20211021123913.48833-1-pulehui@huawei.com

samples/bpf: Fix application of sizeof to pointer

2021-10-20T17:55:33+00:00

The coccinelle check report: "./samples/bpf/xdp_redirect_cpu_user.c:397:32-38: ERROR: application of sizeof to pointer" Using the "strlen" to fix it. Reported-by: Zeal Robot Signed-off-by: David Yang Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20211012111649.983253-1-davidcomponentone@gmail.com