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2021-05-25bpftool: Add sock_release help info for cgroup attach/prog load commandLiu Jian
The help information was not added at the time when the function got added. Fix this and add the missing information to its cli, documentation and bash completion. Fixes: db94cc0b4805 ("bpftool: Add support for BPF_CGROUP_INET_SOCK_RELEASE") Signed-off-by: Liu Jian <liujian56@huawei.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Quentin Monnet <quentin@isovalent.com> Link: https://lore.kernel.org/bpf/20210525014139.323859-1-liujian56@huawei.com
2021-04-23bpftool: Dump more info about DATASEC membersAndrii Nakryiko
Dump succinct information for each member of DATASEC: its kinds and name. This is extremely helpful to see at a quick glance what is inside each DATASEC of a given BTF. Without this, one has to jump around BTF data to just find out the name of a VAR or FUNC. DATASEC's var_secinfo member is special in that regard because it doesn't itself contain the name of the member, delegating that to the referenced VAR and FUNC kinds. Other kinds, like STRUCT/UNION/FUNC/ENUM, encode member names directly and thus are clearly identifiable in BTF dump. The new output looks like this: [35] DATASEC '.bss' size=0 vlen=6 type_id=8 offset=0 size=4 (VAR 'input_bss1') type_id=13 offset=0 size=4 (VAR 'input_bss_weak') type_id=16 offset=0 size=4 (VAR 'output_bss1') type_id=17 offset=0 size=4 (VAR 'output_data1') type_id=18 offset=0 size=4 (VAR 'output_rodata1') type_id=20 offset=0 size=8 (VAR 'output_sink1') [36] DATASEC '.data' size=0 vlen=2 type_id=9 offset=0 size=4 (VAR 'input_data1') type_id=14 offset=0 size=4 (VAR 'input_data_weak') [37] DATASEC '.kconfig' size=0 vlen=2 type_id=25 offset=0 size=4 (VAR 'LINUX_KERNEL_VERSION') type_id=28 offset=0 size=1 (VAR 'CONFIG_BPF_SYSCALL') [38] DATASEC '.ksyms' size=0 vlen=1 type_id=30 offset=0 size=1 (VAR 'bpf_link_fops') [39] DATASEC '.rodata' size=0 vlen=2 type_id=12 offset=0 size=4 (VAR 'input_rodata1') type_id=15 offset=0 size=4 (VAR 'input_rodata_weak') [40] DATASEC 'license' size=0 vlen=1 type_id=24 offset=0 size=4 (VAR 'LICENSE') Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20210423181348.1801389-3-andrii@kernel.org
2021-04-23bpftool: Support dumping BTF VAR's "extern" linkageAndrii Nakryiko
Add dumping of "extern" linkage for BTF VAR kind. Also shorten "global-allocated" to "global" to be in line with FUNC's "global". Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20210423181348.1801389-2-andrii@kernel.org
2021-04-15bpftool: Fix a clang compilation warningYonghong Song
With clang compiler: make -j60 LLVM=1 LLVM_IAS=1 <=== compile kernel # build selftests/bpf or bpftool make -j60 -C tools/testing/selftests/bpf LLVM=1 LLVM_IAS=1 make -j60 -C tools/bpf/bpftool LLVM=1 LLVM_IAS=1 the following compilation warning showed up, net.c:160:37: warning: comparison of integers of different signs: '__u32' (aka 'unsigned int') and 'int' [-Wsign-compare] for (nh = (struct nlmsghdr *)buf; NLMSG_OK(nh, len); ^~~~~~~~~~~~~~~~~ .../tools/include/uapi/linux/netlink.h:99:24: note: expanded from macro 'NLMSG_OK' (nlh)->nlmsg_len <= (len)) ~~~~~~~~~~~~~~~~ ^ ~~~ In this particular case, "len" is defined as "int" and (nlh)->nlmsg_len is "unsigned int". The macro NLMSG_OK is defined as below in uapi/linux/netlink.h. #define NLMSG_OK(nlh,len) ((len) >= (int)sizeof(struct nlmsghdr) && \ (nlh)->nlmsg_len >= sizeof(struct nlmsghdr) && \ (nlh)->nlmsg_len <= (len)) The clang compiler complains the comparision "(nlh)->nlmsg_len <= (len))", but in bpftool/net.c, it is already ensured that "len > 0" must be true. So theoretically the compiler could deduce that comparison of "(nlh)->nlmsg_len" and "len" is okay, but this really depends on compiler internals. Let us add an explicit type conversion (from "int" to "unsigned int") for "len" in NLMSG_OK to silence this warning right now. Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20210413153435.3029635-1-yhs@fb.com
2021-04-01sock_map: Introduce BPF_SK_SKB_VERDICTCong Wang
Reusing BPF_SK_SKB_STREAM_VERDICT is possible but its name is confusing and more importantly we still want to distinguish them from user-space. So we can just reuse the stream verdict code but introduce a new type of eBPF program, skb_verdict. Users are not allowed to attach stream_verdict and skb_verdict programs to the same map. Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20210331023237.41094-10-xiyou.wangcong@gmail.com
2021-03-18bpftool: Add `gen object` command to perform BPF static linkingAndrii Nakryiko
Add `bpftool gen object <output-file> <input_file>...` command to statically link multiple BPF ELF object files into a single output BPF ELF object file. This patch also updates bash completions and man page. Man page gets a short section on `gen object` command, but also updates the skeleton example to show off workflow for BPF application with two .bpf.c files, compiled individually with Clang, then resulting object files are linked together with `gen object`, and then final object file is used to generate usable BPF skeleton. This should help new users understand realistic workflow w.r.t. compiling mutli-file BPF application. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Reviewed-by: Quentin Monnet <quentin@isovalent.com> Link: https://lore.kernel.org/bpf/20210318194036.3521577-10-andrii@kernel.org
2021-03-18bpftool: Add ability to specify custom skeleton object nameAndrii Nakryiko
Add optional name OBJECT_NAME parameter to `gen skeleton` command to override default object name, normally derived from input file name. This allows much more flexibility during build time. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20210318194036.3521577-9-andrii@kernel.org
2021-03-16bpftool: Fix maybe-uninitialized warningsAndrii Nakryiko
Somehow when bpftool is compiled in -Og mode, compiler produces new warnings about possibly uninitialized variables. Fix all the reported problems. Fixes: 2119f2189df1 ("bpftool: add C output format option to btf dump subcommand") Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20210313210920.1959628-3-andrii@kernel.org
2021-03-09Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextDavid S. Miller
Alexei Starovoitov says: ==================== pull-request: bpf-next 2021-03-09 The following pull-request contains BPF updates for your *net-next* tree. We've added 90 non-merge commits during the last 17 day(s) which contain a total of 114 files changed, 5158 insertions(+), 1288 deletions(-). The main changes are: 1) Faster bpf_redirect_map(), from Björn. 2) skmsg cleanup, from Cong. 3) Support for floating point types in BTF, from Ilya. 4) Documentation for sys_bpf commands, from Joe. 5) Support for sk_lookup in bpf_prog_test_run, form Lorenz. 6) Enable task local storage for tracing programs, from Song. 7) bpf_for_each_map_elem() helper, from Yonghong. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-04tools/bpf: Remove bpf-helpers from bpftool docsJoe Stringer
This logic is used for validating the manual pages from selftests, so move the infra under tools/testing/selftests/bpf/ and rely on selftests for validation rather than tying it into the bpftool build. Signed-off-by: Joe Stringer <joe@cilium.io> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Reviewed-by: Quentin Monnet <quentin@isovalent.com> Acked-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://lore.kernel.org/bpf/20210302171947.2268128-12-joe@cilium.io
2021-03-04tools/bpftool: Add BTF_KIND_FLOAT supportIlya Leoshkevich
Only dumping support needs to be adjusted, the code structure follows that of BTF_KIND_INT. Example plain and JSON outputs: [4] FLOAT 'float' size=4 {"id":4,"kind":"FLOAT","name":"float","size":4} Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20210226202256.116518-5-iii@linux.ibm.com
2021-02-26bpftool: Print subprog address properlyYonghong Song
With later hashmap example, using bpftool xlated output may look like: int dump_task(struct bpf_iter__task * ctx): ; struct task_struct *task = ctx->task; 0: (79) r2 = *(u64 *)(r1 +8) ; if (task == (void *)0 || called > 0) ... 19: (18) r2 = subprog[+17] 30: (18) r2 = subprog[+25] ... 36: (95) exit __u64 check_hash_elem(struct bpf_map * map, __u32 * key, __u64 * val, struct callback_ctx * data): ; struct bpf_iter__task *ctx = data->ctx; 37: (79) r5 = *(u64 *)(r4 +0) ... 55: (95) exit __u64 check_percpu_elem(struct bpf_map * map, __u32 * key, __u64 * val, void * unused): ; check_percpu_elem(struct bpf_map *map, __u32 *key, __u64 *val, void *unused) 56: (bf) r6 = r3 ... 83: (18) r2 = subprog[-47] Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20210226204931.3885458-1-yhs@fb.com
2021-02-24bpf: Add kernel/modules BTF presence checks to bpftool feature commandGrant Seltzer
This adds both the CONFIG_DEBUG_INFO_BTF and CONFIG_DEBUG_INFO_BTF_MODULES kernel compile option to output of the bpftool feature command. This is relevant for developers that want to account for data structure definition differences between kernels. Signed-off-by: Grant Seltzer <grantseltzer@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/bpf/20210222195846.155483-1-grantseltzer@gmail.com
2021-02-22Merge tag 'perf-tools-for-v5.12-2020-02-19' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux Pull perf tool updates from Arnaldo Carvalho de Melo: "New features: - Support instruction latency in 'perf report', with both memory latency (weight) and instruction latency information, users can locate expensive load instructions and understand time spent in different stages. - Extend 'perf c2c' to display the number of loads which were blocked by data or address conflict. - Add 'perf stat' support for L2 topdown events in systems such as Intel's Sapphire rapids server. - Add support for PERF_SAMPLE_CODE_PAGE_SIZE in various tools, as a sort key, for instance: perf report --stdio --sort=comm,symbol,code_page_size - New 'perf daemon' command to run long running sessions while providing a way to control the enablement of events without restarting a traditional 'perf record' session. - Enable counting events for BPF programs in 'perf stat' just like for other targets (tid, cgroup, cpu, etc), e.g.: # perf stat -e ref-cycles,cycles -b 254 -I 1000 1.487903822 115,200 ref-cycles 1.487903822 86,012 cycles 2.489147029 80,560 ref-cycles 2.489147029 73,784 cycles ^C The example above counts 'cycles' and 'ref-cycles' of BPF program of id 254. It is similar to bpftool-prog-profile command, but more flexible. - Support the new layout for PERF_RECORD_MMAP2 to carry the DSO build-id using infrastructure generalised from the eBPF subsystem, removing the need for traversing the perf.data file to collect build-ids at the end of 'perf record' sessions and helping with long running sessions where binaries can get replaced in updates, leading to possible mis-resolution of symbols. - Support filtering by hex address in 'perf script'. - Support DSO filter in 'perf script', like in other perf tools. - Add namespaces support to 'perf inject' - Add support for SDT (Dtrace Style Markers) events on ARM64. perf record: - Fix handling of eventfd() when draining a buffer in 'perf record'. - Improvements to the generation of metadata events for pre-existing threads (mmaps, comm, etc), speeding up the work done at the start of system wide or per CPU 'perf record' sessions. Hardware tracing: - Initial support for tracing KVM with Intel PT. - Intel PT fixes for IPC - Support Intel PT PSB (synchronization packets) events. - Automatically group aux-output events to overcome --filter syntax. - Enable PERF_SAMPLE_DATA_SRC on ARMs SPE. - Update ARM's CoreSight hardware tracing OpenCSD library to v1.0.0. perf annotate TUI: - Fix handling of 'k' ("show line number") hotkey - Fix jump parsing for C++ code. perf probe: - Add protection to avoid endless loop. cgroups: - Avoid reading cgroup mountpoint multiple times, caching it. - Fix handling of cgroup v1/v2 in mixed hierarchy. Symbol resolving: - Add OCaml symbol demangling. - Further fixes for handling PE executables when using perf with Wine and .exe/.dll files. - Fix 'perf unwind' DSO handling. - Resolve symbols against debug file first, to deal with artifacts related to LTO. - Fix gap between kernel end and module start on powerpc. Reporting tools: - The DSO filter shouldn't show samples in unresolved maps. - Improve debuginfod support in various tools. build ids: - Fix 16-byte build ids in 'perf buildid-cache', add a 'perf test' entry for that case. perf test: - Support for PERF_SAMPLE_WEIGHT_STRUCT. - Add test case for PERF_SAMPLE_CODE_PAGE_SIZE. - Shell based tests for 'perf daemon's commands ('start', 'stop, 'reconfig', 'list', etc). - ARM cs-etm 'perf test' fixes. - Add parse-metric memory bandwidth testcase. Compiler related: - Fix 'perf probe' kretprobe issue caused by gcc 11 bug when used with -fpatchable-function-entry. - Fix ARM64 build with gcc 11's -Wformat-overflow. - Fix unaligned access in sample parsing test. - Fix printf conversion specifier for IP addresses on arm64, s390 and powerpc. Arch specific: - Support exposing Performance Monitor Counter SPRs as part of extended regs on powerpc. - Add JSON 'perf stat' metrics for ARM64's imx8mp, imx8mq and imx8mn DDR, fix imx8mm ones. - Fix common and uarch events for ARM64's A76 and Ampere eMag" * tag 'perf-tools-for-v5.12-2020-02-19' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux: (148 commits) perf buildid-cache: Don't skip 16-byte build-ids perf buildid-cache: Add test for 16-byte build-id perf symbol: Remove redundant libbfd checks perf test: Output the sub testing result in cs-etm perf test: Suppress logs in cs-etm testing perf tools: Fix arm64 build error with gcc-11 perf intel-pt: Add documentation for tracing virtual machines perf intel-pt: Split VM-Entry and VM-Exit branches perf intel-pt: Adjust sample flags for VM-Exit perf intel-pt: Allow for a guest kernel address filter perf intel-pt: Support decoding of guest kernel perf machine: Factor out machine__idle_thread() perf machine: Factor out machines__find_guest() perf intel-pt: Amend decoder to track the NR flag perf intel-pt: Retain the last PIP packet payload as is perf intel_pt: Add vmlaunch and vmresume as branches perf script: Add branch types for VM-Entry and VM-Exit perf auxtrace: Automatically group aux-output events perf test: Fix unaligned access in sample parsing test perf tools: Support arch specific PERF_SAMPLE_WEIGHT_STRUCT processing ...
2021-02-11bpf: Count the number of times recursion was preventedAlexei Starovoitov
Add per-program counter for number of times recursion prevention mechanism was triggered and expose it via show_fdinfo and bpf_prog_info. Teach bpftool to print it. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20210210033634.62081-7-alexei.starovoitov@gmail.com
2021-01-29tools: Factor Clang, LLC and LLVM utils definitionsSedat Dilek
When dealing with BPF/BTF/pahole and DWARF v5 I wanted to build bpftool. While looking into the source code I found duplicate assignments in misc tools for the LLVM eco system, e.g. clang and llvm-objcopy. Move the Clang, LLC and/or LLVM utils definitions to tools/scripts/Makefile.include file and add missing includes where needed. Honestly, I was inspired by the commit c8a950d0d3b9 ("tools: Factor HOSTCC, HOSTLD, HOSTAR definitions"). I tested with bpftool and perf on Debian/testing AMD64 and LLVM/Clang v11.1.0-rc1. Build instructions: [ make and make-options ] MAKE="make V=1" MAKE_OPTS="HOSTCC=clang HOSTCXX=clang++ HOSTLD=ld.lld CC=clang LD=ld.lld LLVM=1 LLVM_IAS=1" MAKE_OPTS="$MAKE_OPTS PAHOLE=/opt/pahole/bin/pahole" [ clean-up ] $MAKE $MAKE_OPTS -C tools/ clean [ bpftool ] $MAKE $MAKE_OPTS -C tools/bpf/bpftool/ [ perf ] PYTHON=python3 $MAKE $MAKE_OPTS -C tools/perf/ I was careful with respecting the user's wish to override custom compiler, linker, GNU/binutils and/or LLVM utils settings. Signed-off-by: Sedat Dilek <sedat.dilek@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Jiri Olsa <jolsa@redhat.com> # tools/build and tools/perf Link: https://lore.kernel.org/bpf/20210128015117.20515-1-sedat.dilek@gmail.com
2021-01-20Merge remote-tracking branch 'torvalds/master' into perf/coreArnaldo Carvalho de Melo
To pick up fixes. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2021-01-15bpftool: Add Makefile target bootstrapSong Liu
This target is used to only build the bootstrap bpftool, which will be used to generate bpf skeletons for other tools, like perf. Signed-off-by: Song Liu <songliubraving@fb.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: kernel-team@fb.com Link: http://lore.kernel.org/lkml/20201228174054.907740-2-songliubraving@fb.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2021-01-13tools/bpftool: Add -Wall when building BPF programsIan Rogers
No additional warnings are generated by enabling this, but having it enabled will help avoid regressions. Signed-off-by: Ian Rogers <irogers@google.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20210113223609.3358812-2-irogers@google.com
2021-01-06bpftool: Fix compilation failure for net.o with older glibcAlan Maguire
For older glibc ~2.17, #include'ing both linux/if.h and net/if.h fails due to complaints about redefinition of interface flags: CC net.o In file included from net.c:13:0: /usr/include/linux/if.h:71:2: error: redeclaration of enumerator ‘IFF_UP’ IFF_UP = 1<<0, /* sysfs */ ^ /usr/include/net/if.h:44:5: note: previous definition of ‘IFF_UP’ was here IFF_UP = 0x1, /* Interface is up. */ The issue was fixed in kernel headers in [1], but since compilation of net.c picks up system headers the problem can recur. Dropping #include <linux/if.h> resolves the issue and it is not needed for compilation anyhow. [1] https://lore.kernel.org/netdev/1461512707-23058-1-git-send-email-mikko.rapeli__34748.27880641$1462831734$gmane$org@iki.fi/ Fixes: f6f3bac08ff9 ("tools/bpf: bpftool: add net support") Signed-off-by: Alan Maguire <alan.maguire@oracle.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/bpf/1609948746-15369-1-git-send-email-alan.maguire@oracle.com
2020-12-11Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
xdp_return_frame_bulk() needs to pass a xdp_buff to __xdp_return(). strlcpy got converted to strscpy but here it makes no functional difference, so just keep the right code. Conflicts: net/netfilter/nf_tables_api.c Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-12-08tools/bpftool: Fix PID fetching with a lot of resultsAndrii Nakryiko
In case of having so many PID results that they don't fit into a singe page (4096) bytes, bpftool will erroneously conclude that it got corrupted data due to 4096 not being a multiple of struct pid_iter_entry, so the last entry will be partially truncated. Fix this by sizing the buffer to fit exactly N entries with no truncation in the middle of record. Fixes: d53dee3fe013 ("tools/bpftool: Show info for processes holding BPF map/prog/link/btf FDs") Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20201204232002.3589803-1-andrii@kernel.org
2020-12-04Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextJakub Kicinski
Alexei Starovoitov says: ==================== pull-request: bpf-next 2020-12-03 The main changes are: 1) Support BTF in kernel modules, from Andrii. 2) Introduce preferred busy-polling, from Björn. 3) bpf_ima_inode_hash() and bpf_bprm_opts_set() helpers, from KP Singh. 4) Memcg-based memory accounting for bpf objects, from Roman. 5) Allow bpf_{s,g}etsockopt from cgroup bind{4,6} hooks, from Stanislav. * https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (118 commits) selftests/bpf: Fix invalid use of strncat in test_sockmap libbpf: Use memcpy instead of strncpy to please GCC selftests/bpf: Add fentry/fexit/fmod_ret selftest for kernel module selftests/bpf: Add tp_btf CO-RE reloc test for modules libbpf: Support attachment of BPF tracing programs to kernel modules libbpf: Factor out low-level BPF program loading helper bpf: Allow to specify kernel module BTFs when attaching BPF programs bpf: Remove hard-coded btf_vmlinux assumption from BPF verifier selftests/bpf: Add CO-RE relocs selftest relying on kernel module BTF selftests/bpf: Add support for marking sub-tests as skipped selftests/bpf: Add bpf_testmod kernel module for testing libbpf: Add kernel module BTF support for CO-RE relocations libbpf: Refactor CO-RE relocs to not assume a single BTF object libbpf: Add internal helper to load BTF data by FD bpf: Keep module's btf_data_size intact after load bpf: Fix bpf_put_raw_tracepoint()'s use of __module_address() selftests/bpf: Add Userspace tests for TCP_WINDOW_CLAMP bpf: Adds support for setting window clamp samples/bpf: Fix spelling mistake "recieving" -> "receiving" bpf: Fix cold build of test_progs-no_alu32 ... ==================== Link: https://lore.kernel.org/r/20201204021936.85653-1-alexei.starovoitov@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-12-03Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Conflicts: drivers/net/ethernet/ibm/ibmvnic.c Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-12-03tools/bpftool: Auto-detect split BTFs in common casesAndrii Nakryiko
In case of working with module's split BTF from /sys/kernel/btf/*, auto-substitute /sys/kernel/btf/vmlinux as the base BTF. This makes using bpftool with module BTFs faster and simpler. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20201202065244.530571-4-andrii@kernel.org
2020-12-03tools/bpftool: Emit name <anon> for anonymous BTFsAndrii Nakryiko
For consistency of output, emit "name <anon>" for BTFs without the name. This keeps output more consistent and obvious. Suggested-by: Song Liu <songliubraving@fb.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20201202065244.530571-2-andrii@kernel.org
2020-11-24bpftool: Fix error return value in build_btf_type_tableZhen Lei
An appropriate return value should be set on the failed path. Fixes: 4d374ba0bf30 ("tools: bpftool: implement "bpftool btf show|list"") Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20201124104100.491-1-thunder.leizhen@huawei.com
2020-11-20bpftool: Add {i,d}tlb_misses support for bpftool profileYonghong Song
Commit 47c09d6a9f67("bpftool: Introduce "prog profile" command") introduced "bpftool prog profile" command which can be used to profile bpf program with metrics like # of instructions, This patch added support for itlb_misses and dtlb_misses. During an internal bpf program performance evaluation, I found these two metrics are also very useful. The following is an example output: $ bpftool prog profile id 324 duration 3 cycles itlb_misses 1885029 run_cnt 5134686073 cycles 306893 itlb_misses $ bpftool prog profile id 324 duration 3 cycles dtlb_misses 1827382 run_cnt 4943593648 cycles 5975636 dtlb_misses $ bpftool prog profile id 324 duration 3 cycles llc_misses 1836527 run_cnt 5019612972 cycles 4161041 llc_misses From the above, we can see quite some dtlb misses, 3 dtlb misses perf prog run. This might be something worth further investigation. Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20201119073039.4060095-1-yhs@fb.com
2020-11-19Merge https://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-14Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextJakub Kicinski
Daniel Borkmann says: ==================== pull-request: bpf-next 2020-11-14 1) Add BTF generation for kernel modules and extend BTF infra in kernel e.g. support for split BTF loading and validation, from Andrii Nakryiko. 2) Support for pointers beyond pkt_end to recognize LLVM generated patterns on inlined branch conditions, from Alexei Starovoitov. 3) Implements bpf_local_storage for task_struct for BPF LSM, from KP Singh. 4) Enable FENTRY/FEXIT/RAW_TP tracing program to use the bpf_sk_storage infra, from Martin KaFai Lau. 5) Add XDP bulk APIs that introduce a defer/flush mechanism to optimize the XDP_REDIRECT path, from Lorenzo Bianconi. 6) Fix a potential (although rather theoretical) deadlock of hashtab in NMI context, from Song Liu. 7) Fixes for cross and out-of-tree build of bpftool and runqslower allowing build for different target archs on same source tree, from Jean-Philippe Brucker. 8) Fix error path in htab_map_alloc() triggered from syzbot, from Eric Dumazet. 9) Move functionality from test_tcpbpf_user into the test_progs framework so it can run in BPF CI, from Alexander Duyck. 10) Lift hashtab key_size limit to be larger than MAX_BPF_STACK, from Florian Lehner. Note that for the fix from Song we have seen a sparse report on context imbalance which requires changes in sparse itself for proper annotation detection where this is currently being discussed on linux-sparse among developers [0]. Once we have more clarification/guidance after their fix, Song will follow-up. [0] https://lore.kernel.org/linux-sparse/CAHk-=wh4bx8A8dHnX612MsDO13st6uzAz1mJ1PaHHVevJx_ZCw@mail.gmail.com/T/ https://lore.kernel.org/linux-sparse/20201109221345.uklbp3lzgq6g42zb@ltop.local/T/ * git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (66 commits) net: mlx5: Add xdp tx return bulking support net: mvpp2: Add xdp tx return bulking support net: mvneta: Add xdp tx return bulking support net: page_pool: Add bulk support for ptr_ring net: xdp: Introduce bulking for xdp tx return path bpf: Expose bpf_d_path helper to sleepable LSM hooks bpf: Augment the set of sleepable LSM hooks bpf: selftest: Use bpf_sk_storage in FENTRY/FEXIT/RAW_TP bpf: Allow using bpf_sk_storage in FENTRY/FEXIT/RAW_TP bpf: Rename some functions in bpf_sk_storage bpf: Folding omem_charge() into sk_storage_charge() selftests/bpf: Add asm tests for pkt vs pkt_end comparison. selftests/bpf: Add skb_pkt_end test bpf: Support for pointers beyond pkt_end. tools/bpf: Always run the *-clean recipes tools/bpf: Add bootstrap/ to .gitignore bpf: Fix NULL dereference in bpf_task_storage tools/bpftool: Fix build slowdown tools/runqslower: Build bpftool using HOSTCC tools/runqslower: Enable out-of-tree build ... ==================== Link: https://lore.kernel.org/r/20201114020819.29584-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-13tools, bpftool: Add missing close before bpftool net attach exitWang Hai
progfd is created by prog_parse_fd() in do_attach() and before the latter returns in case of success, the file descriptor should be closed. Fixes: 04949ccc273e ("tools: bpftool: add net attach command to attach XDP on interface") Signed-off-by: Wang Hai <wanghai38@huawei.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20201113115152.53178-1-wanghai38@huawei.com
2020-11-12tools/bpf: Always run the *-clean recipesJean-Philippe Brucker
Make $(LIBBPF)-clean and $(LIBBPF_BOOTSTRAP)-clean .PHONY targets, in case those files exist. And keep consistency within the Makefile by making the directory dependencies order-only. Suggested-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20201112091049.3159055-2-jean-philippe@linaro.org
2020-11-12tools/bpf: Add bootstrap/ to .gitignoreJean-Philippe Brucker
Commit 8859b0da5aac ("tools/bpftool: Fix cross-build") added a build-time bootstrap/ directory for bpftool, and removed bpftool-bootstrap. Update .gitignore accordingly. Reported-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20201112091049.3159055-1-jean-philippe@linaro.org
2020-11-11tools/bpftool: Fix build slowdownJean-Philippe Brucker
Commit ba2fd563b740 ("tools/bpftool: Support passing BPFTOOL_VERSION to make") changed BPFTOOL_VERSION to a recursively expanded variable, forcing it to be recomputed on every expansion of CFLAGS and dramatically slowing down the bpftool build. Restore BPFTOOL_VERSION as a simply expanded variable, guarded by an ifeq(). Fixes: ba2fd563b740 ("tools/bpftool: Support passing BPFTOOL_VERSION to make") Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20201110164310.2600671-8-jean-philippe@linaro.org
2020-11-11tools/bpftool: Fix cross-buildJean-Philippe Brucker
The bpftool build first creates an intermediate binary, executed on the host, to generate skeletons required by the final build. When cross-building bpftool for an architecture different from the host, the intermediate binary should be built using the host compiler (gcc) and the final bpftool using the cross compiler (e.g. aarch64-linux-gnu-gcc). Generate the intermediate objects into the bootstrap/ directory using the host toolchain. Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20201110164310.2600671-4-jean-philippe@linaro.org
2020-11-11tools/bpftool: Force clean of out-of-tree buildJean-Philippe Brucker
Cleaning a partial build can fail if the output directory for libbpf wasn't created: $ make -C tools/bpf/bpftool O=/tmp/bpf clean /bin/sh: line 0: cd: /tmp/bpf/libbpf/: No such file or directory tools/scripts/Makefile.include:17: *** output directory "/tmp/bpf/libbpf/" does not exist. Stop. make: *** [Makefile:36: /tmp/bpf/libbpf/libbpf.a-clean] Error 2 As a result make never gets around to clearing the leftover objects. Add the libbpf output directory as clean dependency to ensure clean always succeeds (similarly to the "descend" macro). The directory is later removed by the clean recipe. Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20201110164310.2600671-3-jean-philippe@linaro.org
2020-11-10tools/bpftool: Add support for in-kernel and named BTF in `btf show`Andrii Nakryiko
Display vmlinux BTF name and kernel module names when listing available BTFs on the system. In human-readable output mode, module BTFs are reported with "name [module-name]", while vmlinux BTF will be reported as "name [vmlinux]". Square brackets are added by bpftool and follow kernel convention when displaying modules in human-readable text outputs. [vmuser@archvm bpf]$ sudo ../../../bpf/bpftool/bpftool btf s 1: name [vmlinux] size 4082281B 6: size 2365B prog_ids 8,6 map_ids 3 7: name [button] size 46895B 8: name [pcspkr] size 42328B 9: name [serio_raw] size 39375B 10: name [floppy] size 57185B 11: name [i2c_core] size 76186B 12: name [crc32c_intel] size 16036B 13: name [i2c_piix4] size 50497B 14: name [irqbypass] size 14124B 15: name [kvm] size 197985B 16: name [kvm_intel] size 123564B 17: name [cryptd] size 42466B 18: name [crypto_simd] size 17187B 19: name [glue_helper] size 39205B 20: name [aesni_intel] size 41034B 25: size 36150B pids bpftool(2519) In JSON mode, two fields (boolean "kernel" and string "name") are reported for each BTF object. vmlinux BTF is reported with name "vmlinux" (kernel itself returns and empty name for vmlinux BTF). [vmuser@archvm bpf]$ sudo ../../../bpf/bpftool/bpftool btf s -jp [{ "id": 1, "size": 4082281, "prog_ids": [], "map_ids": [], "kernel": true, "name": "vmlinux" },{ "id": 6, "size": 2365, "prog_ids": [8,6 ], "map_ids": [3 ], "kernel": false },{ "id": 7, "size": 46895, "prog_ids": [], "map_ids": [], "kernel": true, "name": "button" },{ ... Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Tested-by: Alan Maguire <alan.maguire@oracle.com> Link: https://lore.kernel.org/bpf/20201110011932.3201430-6-andrii@kernel.org
2020-11-06bpftool: Add support for task local storageKP Singh
Updates the binary to handle the BPF_MAP_TYPE_TASK_STORAGE as "task_storage" for printing and parsing. Also updates the documentation and bash completion Signed-off-by: KP Singh <kpsingh@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Acked-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/bpf/20201106103747.2780972-5-kpsingh@chromium.org
2020-11-05tools/bpftool: Add bpftool support for split BTFAndrii Nakryiko
Add ability to work with split BTF by providing extra -B flag, which allows to specify the path to the base BTF file. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20201105043402.2530976-12-andrii@kernel.org
2020-11-05tools/bpftool: Fix attaching flow dissectorLorenz Bauer
My earlier patch to reject non-zero arguments to flow dissector attach broke attaching via bpftool. Instead of 0 it uses -1 for target_fd. Fix this by passing a zero argument when attaching the flow dissector. Fixes: 1b514239e859 ("bpf: flow_dissector: Check value of unused flags to BPF_PROG_ATTACH") Reported-by: Jiri Benc <jbenc@redhat.com> Signed-off-by: Lorenz Bauer <lmb@cloudflare.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20201105115230.296657-1-lmb@cloudflare.com
2020-10-29tools, bpftool: Remove two unused variables.Ian Rogers
Avoid an unused variable warning. Signed-off-by: Ian Rogers <irogers@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Tobias Klauser <tklauser@distanz.ch> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20201027233646.3434896-2-irogers@google.com
2020-10-29tools, bpftool: Avoid array index warnings.Ian Rogers
The bpf_caps array is shorter without CAP_BPF, avoid out of bounds reads if this isn't defined. Working around this avoids -Wno-array-bounds with clang. Signed-off-by: Ian Rogers <irogers@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Tobias Klauser <tklauser@distanz.ch> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20201027233646.3434896-1-irogers@google.com
2020-10-05Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller
Rejecting non-native endian BTF overlapped with the addition of support for it. The rest were more simple overlapping changes, except the renesas ravb binding update, which had to follow a file move as well as a YAML conversion. Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-19tools/bpftool: Support passing BPFTOOL_VERSION to makeTony Ambardar
This change facilitates out-of-tree builds, packaging, and versioning for test and debug purposes. Defining BPFTOOL_VERSION allows self-contained builds within the tools tree, since it avoids use of the 'kernelversion' target in the top-level makefile, which would otherwise pull in several other includes from outside the tools tree. Signed-off-by: Tony Ambardar <Tony.Ambardar@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Quentin Monnet <quentin@isovalent.com> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20200917115833.1235518-1-Tony.Ambardar@gmail.com
2020-09-15bpftool: Support dumping metadataYiFei Zhu
Dump metadata in the 'bpftool prog' list if it's present. For some formatting some BTF code is put directly in the metadata dumping. Sanity checks on the map and the kind of the btf_type to make sure we are actually dumping what we are expecting. A helper jsonw_reset is added to json writer so we can reuse the same json writer without having extraneous commas. Sample output: $ bpftool prog 6: cgroup_skb name prog tag bcf7977d3b93787c gpl [...] btf_id 4 metadata: a = "foo" b = 1 $ bpftool prog --json --pretty [{ "id": 6, [...] "btf_id": 4, "metadata": { "a": "foo", "b": 1 } } ] Signed-off-by: YiFei Zhu <zhuyifei@google.com> Signed-off-by: Stanislav Fomichev <sdf@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Cc: YiFei Zhu <zhuyifei1999@gmail.com> Link: https://lore.kernel.org/bpf/20200915234543.3220146-5-sdf@google.com
2020-09-14bpftool: Fix build failureYonghong Song
When building bpf selftests like make -C tools/testing/selftests/bpf -j20 I hit the following errors: ... GEN /net-next/tools/testing/selftests/bpf/tools/build/bpftool/Documentation/bpftool-gen.8 <stdin>:75: (WARNING/2) Block quote ends without a blank line; unexpected unindent. <stdin>:71: (WARNING/2) Literal block ends without a blank line; unexpected unindent. <stdin>:85: (WARNING/2) Literal block ends without a blank line; unexpected unindent. <stdin>:57: (WARNING/2) Block quote ends without a blank line; unexpected unindent. <stdin>:66: (WARNING/2) Literal block ends without a blank line; unexpected unindent. <stdin>:109: (WARNING/2) Literal block ends without a blank line; unexpected unindent. <stdin>:175: (WARNING/2) Literal block ends without a blank line; unexpected unindent. <stdin>:273: (WARNING/2) Literal block ends without a blank line; unexpected unindent. make[1]: *** [/net-next/tools/testing/selftests/bpf/tools/build/bpftool/Documentation/bpftool-perf.8] Error 12 make[1]: *** Waiting for unfinished jobs.... make[1]: *** [/net-next/tools/testing/selftests/bpf/tools/build/bpftool/Documentation/bpftool-iter.8] Error 12 make[1]: *** [/net-next/tools/testing/selftests/bpf/tools/build/bpftool/Documentation/bpftool-struct_ops.8] Error 12 ... I am using: -bash-4.4$ rst2man --version rst2man (Docutils 0.11 [repository], Python 2.7.5, on linux2) -bash-4.4$ The Makefile generated final .rst file (e.g., bpftool-cgroup.rst) looks like ... ID AttachType AttachFlags Name \n SEE ALSO\n========\n\t**bpf**\ (2),\n\t**bpf-helpers**\ (7),\n\t**bpftool**\ (8),\n\t**bpftool-btf**\ (8),\n\t**bpftool-feature**\ (8),\n\t**bpftool-gen**\ (8),\n\t**bpftool-iter**\ (8),\n\t**bpftool-link**\ (8),\n\t**bpftool-map**\ (8),\n\t**bpftool-net**\ (8),\n\t**bpftool-perf**\ (8),\n\t**bpftool-prog**\ (8),\n\t**bpftool-struct_ops**\ (8)\n The rst2man generated .8 file looks like Literal block ends without a blank line; unexpected unindent. .sp n SEEALSOn========nt**bpf**(2),nt**bpf\-helpers**(7),nt**bpftool**(8),nt**bpftool\-btf**(8),nt** bpftool\-feature**(8),nt**bpftool\-gen**(8),nt**bpftool\-iter**(8),nt**bpftool\-link**(8),nt** bpftool\-map**(8),nt**bpftool\-net**(8),nt**bpftool\-perf**(8),nt**bpftool\-prog**(8),nt** bpftool\-struct_ops**(8)n Looks like that particular version of rst2man prefers to have actual new line instead of \n. Since `echo -e` may not be available in some environment, let us use `printf`. Format string "%b" is used for `printf` to ensure all escape characters are interpretted properly. Fixes: 18841da98100 ("tools: bpftool: Automate generation for "SEE ALSO" sections in man pages") Suggested-by: Andrii Nakryiko <andrii.nakryiko@gmail.com> Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Acked-by: Andrii Nakryiko <andriin@fb.com> Cc: Quentin Monnet <quentin@isovalent.com> Link: https://lore.kernel.org/bpf/20200914183110.999906-1-yhs@fb.com
2020-09-10tools: bpftool: Automate generation for "SEE ALSO" sections in man pagesQuentin Monnet
The "SEE ALSO" sections of bpftool's manual pages refer to bpf(2), bpf-helpers(7), then all existing bpftool man pages (save the current one). This leads to nearly-identical lists being duplicated in all manual pages. Ideally, when a new page is created, all lists should be updated accordingly, but this has led to omissions and inconsistencies multiple times in the past. Let's take it out of the RST files and generate the "SEE ALSO" sections automatically in the Makefile when generating the man pages. The lists are not really useful in the RST anyway because all other pages are available in the same directory. v3: - Fix conflict with a previous patchset that introduced RST2MAN_OPTS variable passed to rst2man. v2: - Use "echo -n" instead of "printf" in Makefile, to avoid any risk of passing a format string directly to the command. Signed-off-by: Quentin Monnet <quentin@isovalent.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200910203935.25304-1-quentin@isovalent.com
2020-09-10tools: bpftool: Add "inner_map" to "bpftool map create" outer mapsQuentin Monnet
There is no support for creating maps of types array-of-map or hash-of-map in bpftool. This is because the kernel needs an inner_map_fd to collect metadata on the inner maps to be supported by the new map, but bpftool does not provide a way to pass this file descriptor. Add a new optional "inner_map" keyword that can be used to pass a reference to a map, retrieve a fd to that map, and pass it as the inner_map_fd. Add related documentation and bash completion. Note that we can reference the inner map by its name, meaning we can have several times the keyword "name" with different meanings (mandatory outer map name, and possibly a name to use to find the inner_map_fd). The bash completion will offer it just once, and will not suggest "name" on the following command: # bpftool map create /sys/fs/bpf/my_outer_map type hash_of_maps \ inner_map name my_inner_map [TAB] Fixing that specific case seems too convoluted. Completion will work as expected, however, if the outer map name comes first and the "inner_map name ..." is passed second. Signed-off-by: Quentin Monnet <quentin@isovalent.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200910102652.10509-4-quentin@isovalent.com
2020-09-10tools: bpftool: Keep errors for map-of-map dumps if distinct from ENOENTQuentin Monnet
When dumping outer maps or prog_array maps, and on lookup failure, bpftool simply skips the entry with no error message. This is because the kernel returns non-zero when no value is found for the provided key, which frequently happen for those maps if they have not been filled. When such a case occurs, errno is set to ENOENT. It seems unlikely we could receive other error codes at this stage (we successfully retrieved map info just before), but to be on the safe side, let's skip the entry only if errno was ENOENT, and not for the other errors. v3: New patch Signed-off-by: Quentin Monnet <quentin@isovalent.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200910102652.10509-3-quentin@isovalent.com
2020-09-10tools: bpftool: Clean up function to dump map entryQuentin Monnet
The function used to dump a map entry in bpftool is a bit difficult to follow, as a consequence to earlier refactorings. There is a variable ("num_elems") which does not appear to be necessary, and the error handling would look cleaner if moved to its own function. Let's clean it up. No functional change. v2: - v1 was erroneously removing the check on fd maps in an attempt to get support for outer map dumps. This is already working. Instead, v2 focuses on cleaning up the dump_map_elem() function, to avoid similar confusion in the future. Signed-off-by: Quentin Monnet <quentin@isovalent.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200910102652.10509-2-quentin@isovalent.com