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2019-12-19libbpf: Fix printing of ulimit valueToke Høiland-Jørgensen1-1/+1
Naresh pointed out that libbpf builds fail on 32-bit architectures because rlimit.rlim_cur is defined as 'unsigned long long' on those architectures. Fix this by using %zu in printf and casting to size_t. Fixes: dc3a2d254782 ("libbpf: Print hint about ulimit when getting permission denied error") Reported-by: Naresh Kamboju <[email protected]> Signed-off-by: Toke Høiland-Jørgensen <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2019-12-19selftests/bpf: Fix test_attach_probeAlexei Starovoitov1-3/+4
Fix two issues in test_attach_probe: 1. it was not able to parse /proc/self/maps beyond the first line, since %s means parse string until white space. 2. offset has to be accounted for otherwise uprobed address is incorrect. Fixes: 1e8611bbdfc9 ("selftests/bpf: add kprobe/uprobe selftests") Signed-off-by: Alexei Starovoitov <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]> Acked-by: Yonghong Song <[email protected]> Acked-by: Andrii Nakryiko <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2019-12-19libbpf: Add missing newline in opts validation macroToke Høiland-Jørgensen1-1/+1
The error log output in the opts validation macro was missing a newline. Fixes: 2ce8450ef5a3 ("libbpf: add bpf_object__open_{file, mem} w/ extensible opts") Signed-off-by: Toke Høiland-Jørgensen <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2019-12-19riscv, bpf: Add missing uapi header for BPF_PROG_TYPE_PERF_EVENT programsBjörn Töpel1-0/+2
Add missing uapi header the BPF_PROG_TYPE_PERF_EVENT programs by exporting struct user_regs_struct instead of struct pt_regs which is in-kernel only. Signed-off-by: Björn Töpel <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2019-12-18libbpf: BTF is required when externs are presentAndrii Nakryiko1-1/+2
BTF is required to get type information about extern variables. Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2019-12-18libbpf: Allow to augment system Kconfig through extra optional configAndrii Nakryiko3-112/+132
Instead of all or nothing approach of overriding Kconfig file location, allow to extend it with extra values and override chosen subset of values though optional user-provided extra config, passed as a string through open options' .kconfig option. If same config key is present in both user-supplied config and Kconfig, user-supplied one wins. This allows applications to more easily test various conditions despite host kernel's real configuration. If all of BPF object's __kconfig externs are satisfied from user-supplied config, system Kconfig won't be read at all. Simplify selftests by not needing to create temporary Kconfig files. Suggested-by: Alexei Starovoitov <[email protected]> Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2019-12-18libbpf: Put Kconfig externs into .kconfig sectionAndrii Nakryiko6-48/+60
Move Kconfig-provided externs into custom .kconfig section. Add __kconfig into bpf_helpers.h for user convenience. Update selftests accordingly. Suggested-by: Daniel Borkmann <[email protected]> Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2019-12-18libbpf: Add bpf_link__disconnect() API to preserve underlying BPF resourceAndrii Nakryiko3-10/+32
There are cases in which BPF resource (program, map, etc) has to outlive userspace program that "installed" it in the system in the first place. When BPF program is attached, libbpf returns bpf_link object, which is supposed to be destroyed after no longer necessary through bpf_link__destroy() API. Currently, bpf_link destruction causes both automatic detachment and frees up any resources allocated to for bpf_link in-memory representation. This is inconvenient for the case described above because of coupling of detachment and resource freeing. This patch introduces bpf_link__disconnect() API call, which marks bpf_link as disconnected from its underlying BPF resouces. This means that when bpf_link is destroyed later, all its memory resources will be freed, but BPF resource itself won't be detached. This design allows to follow strict and resource-leak-free design by default, while giving easy and straightforward way for user code to opt for keeping BPF resource attached beyond lifetime of a bpf_link. For some BPF programs (i.e., FS-based tracepoints, kprobes, raw tracepoint, etc), user has to make sure to pin BPF program to prevent kernel to automatically detach it on process exit. This should typically be achived by pinning BPF program (or map in some cases) in BPF FS. Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Acked-by: Martin KaFai Lau <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2019-12-18Merge tag 'tpmdd-next-20191219' of git://git.infradead.org/users/jjs/linux-tpmddLinus Torvalds3-2/+36
Pull tpm fixes from Jarkko Sakkinen: "Bunch of fixes for rc3" * tag 'tpmdd-next-20191219' of git://git.infradead.org/users/jjs/linux-tpmdd: tpm/tpm_ftpm_tee: add shutdown call back tpm: selftest: cleanup after unseal with wrong auth/policy test tpm: selftest: add test covering async mode tpm: fix invalid locking in NONBLOCKING mode security: keys: trusted: fix lost handle flush tpm_tis: reserve chip for duration of tpm_tis_core_init KEYS: asymmetric: return ENOMEM if akcipher_request_alloc() fails KEYS: remove CONFIG_KEYS_COMPAT
2019-12-18bpf: Allow to change skb mark in test_runNikita V. Shirokov2-0/+6
allow to pass skb's mark field into bpf_prog_test_run ctx for BPF_PROG_TYPE_SCHED_CLS prog type. that would allow to test bpf programs which are doing decision based on this field Signed-off-by: Nikita V. Shirokov <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]>
2019-12-18bpftool: Work-around rst2man conversion bugAndrii Nakryiko1-7/+8
Work-around what appears to be a bug in rst2man convertion tool, used to create man pages out of reStructureText-formatted documents. If text line starts with dot, rst2man will put it in resulting man file verbatim. This seems to cause man tool to interpret it as a directive/command (e.g., `.bs`), and subsequently not render entire line because it's unrecognized one. Enclose '.xxx' words in extra formatting to work around. Fixes: cb21ac588546 ("bpftool: Add gen subcommand manpage") Reported-by: Alexei Starovoitov <[email protected]> Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Acked-by: Yonghong Song <[email protected] Link: https://lore.kernel.org/bpf/[email protected]
2019-12-18bpftool: Simplify format string to not use positional argsAndrii Nakryiko1-2/+2
Change format string referring to just single argument out of two available. Some versions of libc can reject such format string. Reported-by: Nikita Shirokov <[email protected]> Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Acked-by: Yonghong Song <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2019-12-18selftests: qdiscs: Add test coverage for ETS QdiscPetr Machata1-0/+940
Add TDC coverage for the new ETS Qdisc. Signed-off-by: Petr Machata <[email protected]> Reviewed-by: Ido Schimmel <[email protected]> Signed-off-by: David S. Miller <[email protected]>
2019-12-18selftests: forwarding: sch_ets: Add test coverage for ETS QdiscPetr Machata5-0/+666
This tests the newly-added ETS Qdisc. It runs two to three streams of traffic, each with a different priority. ETS Qdisc is supposed to allocate bandwidth according to the DRR algorithm and given weights. After running the traffic for a while, counters are compared for each stream to check that the expected ratio is in fact observed. In order for the DRR process to kick in, a traffic bottleneck must exist in the first place. In slow path, such bottleneck can be implemented by wrapping the ETS Qdisc inside a TBF or other shaper. This might however make the configuration unoffloadable. Instead, on HW datapath, the bottleneck would be set up by lowering port speed and configuring shared buffer suitably. Therefore the test is structured as a core component that implements the testing, with two wrapper scripts that implement the details of slow path resp. fast path configuration. Signed-off-by: Petr Machata <[email protected]> Reviewed-by: Ido Schimmel <[email protected]> Acked-by: Jiri Pirko <[email protected]> Signed-off-by: David S. Miller <[email protected]>
2019-12-18selftests: forwarding: Move start_/stop_traffic from mlxsw to lib.shPetr Machata2-18/+18
These two functions are used for starting several streams of traffic, and then stopping them later. They will be handy for the test coverage of ETS Qdisc. Move them from mlxsw-specific qos_lib.sh to the generic lib.sh. Signed-off-by: Petr Machata <[email protected]> Reviewed-by: Ido Schimmel <[email protected]> Acked-by: Jiri Pirko <[email protected]> Signed-off-by: David S. Miller <[email protected]>
2019-12-17bpftool: Add gen subcommand manpageAndrii Nakryiko2-1/+306
Add bpftool-gen.rst describing skeleton on the high level. Also include a small, but complete, example BPF app (BPF side, userspace side, generated skeleton) in example section to demonstrate skeleton API and its usage. Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Acked-by: Yonghong Song <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2019-12-17libbpf: Remove BPF_EMBED_OBJ macro from libbpf.hAndrii Nakryiko1-35/+0
Drop BPF_EMBED_OBJ and struct bpf_embed_data now that skeleton automatically embeds contents of its source object file. While BPF_EMBED_OBJ is useful independently of skeleton, we are currently don't have any use cases utilizing it, so let's remove them until/if we need it. Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Acked-by: Yonghong Song <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2019-12-17bpftool, selftests/bpf: Embed object file inside skeletonAndrii Nakryiko9-119/+154
Embed contents of BPF object file used for BPF skeleton generation inside skeleton itself. This allows to keep BPF object file and its skeleton in sync at all times, and simpifies skeleton instantiation. Also switch existing selftests to not require BPF_EMBED_OBJ anymore. Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Acked-by: Yonghong Song <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2019-12-17libbpf: Reduce log level for custom section namesAndrii Nakryiko1-3/+3
Libbpf is trying to recognize BPF program type based on its section name during bpf_object__open() phase. This is not strictly enforced and user code has ability to specify/override correct BPF program type after open. But if BPF program is using custom section name, libbpf will still emit warnings, which can be quite annoying to users. This patch reduces log level of information messages emitted by libbpf if section name is not canonical. User can still get a list of all supported section names as debug-level message. Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2019-12-18libbpf: Fix libbpf_common.h when installing libbpf through 'make install'Toke Høiland-Jørgensen2-0/+3
This fixes two issues with the newly introduced libbpf_common.h file: - The header failed to include <string.h> for the definition of memset() - The new file was not included in the install_headers rule in the Makefile Both of these issues cause breakage when installing libbpf with 'make install' and trying to use it in applications. Fixes: 544402d4b493 ("libbpf: Extract common user-facing helpers") Signed-off-by: Toke Høiland-Jørgensen <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]> Acked-by: Yonghong Song <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2019-12-18selftests/bpf: More succinct Makefile outputAndrii Nakryiko1-0/+36
Similarly to bpftool/libbpf output, make selftests/bpf output succinct per-item output line. Output is roughly as follows: $ make ... CLANG-LLC [test_maps] pyperf600.o CLANG-LLC [test_maps] strobemeta.o CLANG-LLC [test_maps] pyperf100.o EXTRA-OBJ [test_progs] cgroup_helpers.o EXTRA-OBJ [test_progs] trace_helpers.o BINARY test_align BINARY test_verifier_log GEN-SKEL [test_progs] fexit_bpf2bpf.skel.h GEN-SKEL [test_progs] test_global_data.skel.h GEN-SKEL [test_progs] sendmsg6_prog.skel.h ... To see the actual command invocation, verbose mode can be turned on with V=1 argument: $ make V=1 ... very verbose output ... Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]> Acked-by: Yonghong Song <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2019-12-17Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds65-289/+976
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf tooling fixes from Ingo Molnar: "These are all perf tooling changes: most of them are fixes. Note that the large CPU count related fixes go beyond regression fixes, but the IPI-flood symptoms are severe enough that I think justifies their inclusion" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (38 commits) perf vendor events s390: Remove name from L1D_RO_EXCL_WRITES description perf vendor events s390: Fix counter long description for DTLB1_GPAGE_WRITES libtraceevent: Allow custom libdir path perf header: Fix false warning when there are no duplicate cache entries perf metricgroup: Fix printing event names of metric group with multiple events perf/x86/pmu-events: Fix Kernel_Utilization metric perf top: Do not bail out when perf_env__read_cpuid() returns ENOSYS perf arch: Make the default get_cpuid() return compatible error tools headers kvm: Sync linux/kvm.h with the kernel sources tools headers UAPI: Update tools's copy of drm.h headers tools headers UAPI: Sync drm/i915_drm.h with the kernel sources perf inject: Fix processing of ID index for injected instruction tracing perf report: Bail out --mem-mode if mem info is not available perf report: Make -F more strict like -s perf report/top TUI: Replace pr_err() with ui__error() libtraceevent: Copy pkg-config file to output folder when using O= libtraceevent: Fix lib installation with O= perf kvm: Clarify the 'perf kvm' -i and -o command line options tools arch x86: Sync asm/cpufeatures.h with the kernel sources perf beauty: Add CLEAR_SIGHAND support for clone's flags arg ...
2019-12-17tpm: selftest: cleanup after unseal with wrong auth/policy testTadeusz Struk1-0/+5
Unseal with wrong auth or wrong policy test affects DA lockout and eventually causes the tests to fail with: "ProtocolError: TPM_RC_LOCKOUT: rc=0x00000921" when the tests run multiple times. Send tpm clear command after the test to reset the DA counters. Signed-off-by: Tadeusz Struk <[email protected]> Reviewed-by: Jarkko Sakkinen <[email protected]> Signed-off-by: Jarkko Sakkinen <[email protected]>
2019-12-17tpm: selftest: add test covering async modeTadeusz Struk3-2/+31
Add a test that sends a tpm cmd in an async mode. Currently there is a gap in test coverage with regards to this functionality. Signed-off-by: Tadeusz Struk <[email protected]> Reviewed-by: Jarkko Sakkinen <[email protected]> Signed-off-by: Jarkko Sakkinen <[email protected]>
2019-12-16wireguard: selftests: import harness makefile for test suiteJason A. Donenfeld18-0/+947
WireGuard has been using this on build.wireguard.com for the last several years with considerable success. It allows for very quick and iterative development cycles, and supports several platforms. To run the test suite on your current platform in QEMU: $ make -C tools/testing/selftests/wireguard/qemu -j$(nproc) To run it with KASAN and such turned on: $ DEBUG_KERNEL=yes make -C tools/testing/selftests/wireguard/qemu -j$(nproc) To run it emulated for another platform in QEMU: $ ARCH=arm make -C tools/testing/selftests/wireguard/qemu -j$(nproc) At the moment, we support aarch64_be, aarch64, arm, armeb, i686, m68k, mips64, mips64el, mips, mipsel, powerpc64le, powerpc, and x86_64. The system supports incremental rebuilding, so it should be very fast to change a single file and then test it out and have immediate feedback. This requires for the right toolchain and qemu to be installed prior. I've had success with those from musl.cc. This is tailored for WireGuard at the moment, though later projects might generalize it for other network testing. Signed-off-by: Jason A. Donenfeld <[email protected]> Signed-off-by: David S. Miller <[email protected]>
2019-12-16libbpf: Add zlib as a dependency in pkg-config templateAndrii Nakryiko1-1/+1
List zlib as another dependency of libbpf in pkg-config template. Verified it is correctly resolved to proper -lz flag: $ make DESTDIR=/tmp/libbpf-install install $ pkg-config --libs /tmp/libbpf-install/usr/local/lib64/pkgconfig/libbpf.pc -L/usr/local/lib64 -lbpf $ pkg-config --libs --static /tmp/libbpf-install/usr/local/lib64/pkgconfig/libbpf.pc -L/usr/local/lib64 -lbpf -lelf -lz Fixes: 166750bc1dd2 ("libbpf: Support libbpf-provided extern variables") Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Acked-by: Yonghong Song <[email protected]> Cc: Luca Boccassi <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2019-12-16libbpf: Print hint about ulimit when getting permission denied errorToke Høiland-Jørgensen1-0/+29
Probably the single most common error newcomers to XDP are stumped by is the 'permission denied' error they get when trying to load their program and 'ulimit -l' is set too low. For examples, see [0], [1]. Since the error code is UAPI, we can't change that. Instead, this patch adds a few heuristics in libbpf and outputs an additional hint if they are met: If an EPERM is returned on map create or program load, and geteuid() shows we are root, and the current RLIMIT_MEMLOCK is not infinity, we output a hint about raising 'ulimit -l' as an additional log line. [0] https://marc.info/?l=xdp-newbies&m=157043612505624&w=2 [1] https://github.com/xdp-project/xdp-tutorial/issues/86 Signed-off-by: Toke Høiland-Jørgensen <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Acked-by: Jesper Dangaard Brouer <[email protected]> Acked-by: Yonghong Song <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2019-12-16perf vendor events s390: Remove name from L1D_RO_EXCL_WRITES descriptionEd Maste1-1/+1
In 7fcfa9a2d9 an unintended prefix "Counter:18 Name:" was removed from the description for L1D_RO_EXCL_WRITES, but the extra name remained in the description. Remove it too. Fixes: 7fcfa9a2d9a7 ("perf list: Fix s390 counter long description for L1D_RO_EXCL_WRITES") Signed-off-by: Ed Maste <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Greentime Hu <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Nick Hu <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Richter <[email protected]> Cc: Vincent Chen <[email protected]> Link: http://lore.kernel.org/lkml/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2019-12-16perf vendor events s390: Fix counter long description for DTLB1_GPAGE_WRITESEd Maste1-1/+1
The cf_z13 counter DTLB1_GPAGE_WRITES included a prefix 'Counter:132\tName:'. This is incorrect; remove the prefix as with 7fcfa9a2d9 for cf_z14. Signed-off-by: Ed Maste <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Greentime Hu <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Nick Hu <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Richter <[email protected]> Cc: Vincent Chen <[email protected]> Link: http://lore.kernel.org/lkml/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2019-12-16libtraceevent: Allow custom libdir pathSudip Mukherjee2-4/+6
When I use prefix=/usr and try to install libtraceevent in my laptop it tries to install in /usr/lib64. I am not having any folder as /usr/lib64 and also the debian policy doesnot allow installing in /usr/lib64. It should be in /usr/lib/x86_64-linux-gnu/. Quote: No package for a 64 bit architecture may install files in /usr/lib64/ or in a subdirectory of it. ref: https://www.debian.org/doc/debian-policy/ch-opersys.html Make it more flexible by allowing to mention libdir_relative while installing so that distros can mention the path according to their policy or use the default one. Signed-off-by: Sudipm Mukherjee <[email protected]> Reviewed-by: Steven Rostedt (VMware) <[email protected]> Cc: Sudipm Mukherjee <[email protected]> Cc: [email protected] Link: http://lore.kernel.org/lkml/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2019-12-16bpftool: Fix compilation warning on shadowed variablePaul Chaignon1-1/+1
The ident variable has already been declared at the top of the function and doesn't need to be re-declared. Fixes: 985ead416df39 ("bpftool: Add skeleton codegen command") Signed-off-by: Paul Chaignon <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]> Link: https://lore.kernel.org/bpf/20191216112733.GA28366@Omicron
2019-12-16libbpf: Fix build by renaming variablesPrashant Bhole1-6/+6
In btf__align_of() variable name 't' is shadowed by inner block declaration of another variable with same name. Patch renames variables in order to fix it. CC sharedobjs/btf.o btf.c: In function ‘btf__align_of’: btf.c:303:21: error: declaration of ‘t’ shadows a previous local [-Werror=shadow] 303 | int i, align = 1, t; | ^ btf.c:283:25: note: shadowed declaration is here 283 | const struct btf_type *t = btf__type_by_id(btf, id); | Fixes: 3d208f4ca111 ("libbpf: Expose btf__align_of() API") Signed-off-by: Prashant Bhole <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]> Tested-by: Toke Høiland-Jørgensen <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2019-12-15selftests/bpf: Add flexible array relocation testsAndrii Nakryiko6-4/+56
Add few tests validation CO-RE relocation handling of flexible array accesses. Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2019-12-15libbpf: Support flexible arrays in CO-REAndrii Nakryiko1-5/+29
Some data stuctures in kernel are defined with either zero-sized array or flexible (dimensionless) array at the end of a struct. Actual data of such array follows in memory immediately after the end of that struct, forming its variable-sized "body" of elements. Support such access pattern in CO-RE relocation handling. Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2019-12-15selftests/bpf: Add tests for libbpf-provided externsAndrii Nakryiko4-1/+283
Add a set of tests validating libbpf-provided extern variables. One crucial feature that's tested is dead code elimination together with using invalid BPF helper. CONFIG_MISSING is not supposed to exist and should always be specified by libbpf as zero, which allows BPF verifier to correctly do branch pruning and not fail validation, when invalid BPF helper is called from dead if branch. Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2019-12-15bpftool: Generate externs datasec in BPF skeletonAndrii Nakryiko2-5/+9
Add support for generation of mmap()-ed read-only view of libbpf-provided extern variables. As externs are not supposed to be provided by user code (that's what .data, .bss, and .rodata is for), don't mmap() it initially. Only after skeleton load is performed, map .extern contents as read-only memory. Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2019-12-15libbpf: Support libbpf-provided extern variablesAndrii Nakryiko7-65/+727
Add support for extern variables, provided to BPF program by libbpf. Currently the following extern variables are supported: - LINUX_KERNEL_VERSION; version of a kernel in which BPF program is executing, follows KERNEL_VERSION() macro convention, can be 4- and 8-byte long; - CONFIG_xxx values; a set of values of actual kernel config. Tristate, boolean, strings, and integer values are supported. Set of possible values is determined by declared type of extern variable. Supported types of variables are: - Tristate values. Are represented as `enum libbpf_tristate`. Accepted values are **strictly** 'y', 'n', or 'm', which are represented as TRI_YES, TRI_NO, or TRI_MODULE, respectively. - Boolean values. Are represented as bool (_Bool) types. Accepted values are 'y' and 'n' only, turning into true/false values, respectively. - Single-character values. Can be used both as a substritute for bool/tristate, or as a small-range integer: - 'y'/'n'/'m' are represented as is, as characters 'y', 'n', or 'm'; - integers in a range [-128, 127] or [0, 255] (depending on signedness of char in target architecture) are recognized and represented with respective values of char type. - Strings. String values are declared as fixed-length char arrays. String of up to that length will be accepted and put in first N bytes of char array, with the rest of bytes zeroed out. If config string value is longer than space alloted, it will be truncated and warning message emitted. Char array is always zero terminated. String literals in config have to be enclosed in double quotes, just like C-style string literals. - Integers. 8-, 16-, 32-, and 64-bit integers are supported, both signed and unsigned variants. Libbpf enforces parsed config value to be in the supported range of corresponding integer type. Integers values in config can be: - decimal integers, with optional + and - signs; - hexadecimal integers, prefixed with 0x or 0X; - octal integers, starting with 0. Config file itself is searched in /boot/config-$(uname -r) location with fallback to /proc/config.gz, unless config path is specified explicitly through bpf_object_open_opts' kernel_config_path option. Both gzipped and plain text formats are supported. Libbpf adds explicit dependency on zlib because of this, but this shouldn't be a problem, given libelf already depends on zlib. All detected extern variables, are put into a separate .extern internal map. It, similarly to .rodata map, is marked as read-only from BPF program side, as well as is frozen on load. This allows BPF verifier to track extern values as constants and perform enhanced branch prediction and dead code elimination. This can be relied upon for doing kernel version/feature detection and using potentially unsupported field relocations or BPF helpers in a CO-RE-based BPF program, while still having a single version of BPF program running on old and new kernels. Selftests are validating this explicitly for unexisting BPF helper. Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2019-12-15libbpf: Extract internal map names into constantsAndrii Nakryiko1-9/+14
Instead of duplicating string literals, keep them in one place and consistent. Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2019-12-15bpftool: Add `gen skeleton` BASH completionsAndrii Nakryiko1-0/+11
Add BASH completions for gen sub-command. Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Acked-by: Martin KaFai Lau <[email protected]> Cc: Quentin Monnet <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2019-12-15selftests/bpf: Add test validating data section to struct convertion layoutAndrii Nakryiko2-0/+88
Add a simple selftests validating datasection-to-struct layour dumping. Global variables are constructed in such a way as to cause both natural and artificial padding (through custom alignment requirement). Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Acked-by: Martin KaFai Lau <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2019-12-15selftests/bpf: Convert few more selftest to skeletonsAndrii Nakryiko5-249/+149
Convert few more selftests to use generated BPF skeletons as a demonstration on how to use it. Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Acked-by: Martin KaFai Lau <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2019-12-15selftests/bpf: Add BPF skeletons selftests and convert attach_probe.cAndrii Nakryiko4-133/+74
Add BPF skeleton generation to selftest/bpf's Makefile. Convert attach_probe.c to use skeleton. Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Acked-by: Martin KaFai Lau <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2019-12-15bpftool: Add skeleton codegen commandAndrii Nakryiko3-1/+554
Add `bpftool gen skeleton` command, which takes in compiled BPF .o object file and dumps a BPF skeleton struct and related code to work with that skeleton. Skeleton itself is tailored to a specific structure of provided BPF object file, containing accessors (just plain struct fields) for every map and program, as well as dedicated space for bpf_links. If BPF program is using global variables, corresponding structure definitions of compatible memory layout are emitted as well, making it possible to initialize and subsequently read/update global variables values using simple and clear C syntax for accessing fields. This skeleton majorly improves usability of opening/loading/attaching of BPF object, as well as interacting with it throughout the lifetime of loaded BPF object. Generated skeleton struct has the following structure: struct <object-name> { /* used by libbpf's skeleton API */ struct bpf_object_skeleton *skeleton; /* bpf_object for libbpf APIs */ struct bpf_object *obj; struct { /* for every defined map in BPF object: */ struct bpf_map *<map-name>; } maps; struct { /* for every program in BPF object: */ struct bpf_program *<program-name>; } progs; struct { /* for every program in BPF object: */ struct bpf_link *<program-name>; } links; /* for every present global data section: */ struct <object-name>__<one of bss, data, or rodata> { /* memory layout of corresponding data section, * with every defined variable represented as a struct field * with exactly the same type, but without const/volatile * modifiers, e.g.: */ int *my_var_1; ... } *<one of bss, data, or rodata>; }; This provides great usability improvements: - no need to look up maps and programs by name, instead just my_obj->maps.my_map or my_obj->progs.my_prog would give necessary bpf_map/bpf_program pointers, which user can pass to existing libbpf APIs; - pre-defined places for bpf_links, which will be automatically populated for program types that libbpf knows how to attach automatically (currently tracepoints, kprobe/kretprobe, raw tracepoint and tracing programs). On tearing down skeleton, all active bpf_links will be destroyed (meaning BPF programs will be detached, if they are attached). For cases in which libbpf doesn't know how to auto-attach BPF program, user can manually create link after loading skeleton and they will be auto-detached on skeleton destruction: my_obj->links.my_fancy_prog = bpf_program__attach_cgroup_whatever( my_obj->progs.my_fancy_prog, <whatever extra param); - it's extremely easy and convenient to work with global data from userspace now. Both for read-only and read/write variables, it's possible to pre-initialize them before skeleton is loaded: skel = my_obj__open(raw_embed_data); my_obj->rodata->my_var = 123; my_obj__load(skel); /* 123 will be initialization value for my_var */ After load, if kernel supports mmap() for BPF arrays, user can still read (and write for .bss and .data) variables values, but at that point it will be directly mmap()-ed to BPF array, backing global variables. This allows to seamlessly exchange data with BPF side. From userspace program's POV, all the pointers and memory contents stay the same, but mapped kernel memory changes to point to created map. If kernel doesn't yet support mmap() for BPF arrays, it's still possible to use those data section structs to pre-initialize .bss, .data, and .rodata, but after load their pointers will be reset to NULL, allowing user code to gracefully handle this condition, if necessary. Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Acked-by: Martin KaFai Lau <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2019-12-15libbpf: Add BPF object skeleton supportAndrii Nakryiko3-0/+205
Add new set of APIs, allowing to open/load/attach BPF object through BPF object skeleton, generated by bpftool for a specific BPF object file. All the xxx_skeleton() APIs wrap up corresponding bpf_object_xxx() APIs, but additionally also automate map/program lookups by name, global data initialization and mmap()-ing, etc. All this greatly improves and simplifies userspace usability of working with BPF programs. See follow up patches for examples. Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Acked-by: Martin KaFai Lau <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2019-12-15libbpf: Reduce log level of supported section names dumpAndrii Nakryiko1-1/+1
It's quite spammy. And now that bpf_object__open() is trying to determine program type from its section name, we are getting these verbose messages all the time. Reduce their log level to DEBUG. Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Acked-by: Martin KaFai Lau <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2019-12-15libbpf: Postpone BTF ID finding for TRACING programs to load phaseAndrii Nakryiko1-19/+18
Move BTF ID determination for BPF_PROG_TYPE_TRACING programs to a load phase. Performing it at open step is inconvenient, because it prevents BPF skeleton generation on older host kernel, which doesn't contain BTF_KIND_FUNCs information in vmlinux BTF. This is a common set up, though, when, e.g., selftests are compiled on older host kernel, but the test program itself is executed in qemu VM with bleeding edge kernel. Having this BTF searching performed at load time allows to successfully use bpf_object__open() for codegen and inspection of BPF object file. Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Acked-by: Martin KaFai Lau <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2019-12-15libbpf: Refactor global data map initializationAndrii Nakryiko1-38/+59
Refactor global data map initialization to use anonymous mmap()-ed memory instead of malloc()-ed one. This allows to do a transparent re-mmap()-ing of already existing memory address to point to BPF map's memory after bpf_object__load() step (done in follow up patch). This choreographed setup allows to have a nice and unsurprising way to pre-initialize read-only (and r/w as well) maps by user and after BPF map creation keep working with mmap()-ed contents of this map. All in a way that doesn't require user code to update any pointers: the illusion of working with memory contents is preserved before and after actual BPF map instantiation. Selftests and runqslower example demonstrate this feature in follow up patches. Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Acked-by: Martin KaFai Lau <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2019-12-15libbpf: Expose BPF program's function nameAndrii Nakryiko4-14/+36
Add APIs to get BPF program function name, as opposed to bpf_program__title(), which returns BPF program function's section name. Function name has a benefit of being a valid C identifier and uniquely identifies a specific BPF program, while section name can be duplicated across multiple independent BPF programs. Add also bpf_object__find_program_by_name(), similar to bpf_object__find_program_by_title(), to facilitate looking up BPF programs by their C function names. Convert one of selftests to new API for look up. Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Acked-by: Martin KaFai Lau <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2019-12-15libbpf: Expose BTF-to-C type declaration emitting APIAndrii Nakryiko3-26/+65
Expose API that allows to emit type declaration and field/variable definition (if optional field name is specified) in valid C syntax for any provided BTF type. This is going to be used by bpftool when emitting data section layout as a struct. As part of making this API useful in a stand-alone fashion, move initialization of some of the internal btf_dump state to earlier phase. Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Acked-by: Martin KaFai Lau <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2019-12-15libbpf: Expose btf__align_of() APIAndrii Nakryiko4-41/+47
Expose BTF API that calculates type alignment requirements. Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]