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2019-04-10bpf, libbpf: add support for BTF Var and DataSecDaniel Borkmann5-20/+235
This adds libbpf support for BTF Var and DataSec kinds. Main point here is that libbpf needs to do some preparatory work before the whole BTF object can be loaded into the kernel, that is, fixing up of DataSec size taken from the ELF section size and non-static variable offset which needs to be taken from the ELF's string section. Upstream LLVM doesn't fix these up since at time of BTF emission it is too early in the compilation process thus this information isn't available yet, hence loader needs to take care of it. Note, deduplication handling has not been in the scope of this work and needs to be addressed in a future commit. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://reviews.llvm.org/D59441 Acked-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-04-10bpf, libbpf: support global data/bss/rodata sectionsDaniel Borkmann6-48/+314
This work adds BPF loader support for global data sections to libbpf. This allows to write BPF programs in more natural C-like way by being able to define global variables and const data. Back at LPC 2018 [0] we presented a first prototype which implemented support for global data sections by extending BPF syscall where union bpf_attr would get additional memory/size pair for each section passed during prog load in order to later add this base address into the ldimm64 instruction along with the user provided offset when accessing a variable. Consensus from LPC was that for proper upstream support, it would be more desirable to use maps instead of bpf_attr extension as this would allow for introspection of these sections as well as potential live updates of their content. This work follows this path by taking the following steps from loader side: 1) In bpf_object__elf_collect() step we pick up ".data", ".rodata", and ".bss" section information. 2) If present, in bpf_object__init_internal_map() we add maps to the obj's map array that corresponds to each of the present sections. Given section size and access properties can differ, a single entry array map is created with value size that is corresponding to the ELF section size of .data, .bss or .rodata. These internal maps are integrated into the normal map handling of libbpf such that when user traverses all obj maps, they can be differentiated from user-created ones via bpf_map__is_internal(). In later steps when we actually create these maps in the kernel via bpf_object__create_maps(), then for .data and .rodata sections their content is copied into the map through bpf_map_update_elem(). For .bss this is not necessary since array map is already zero-initialized by default. Additionally, for .rodata the map is frozen as read-only after setup, such that neither from program nor syscall side writes would be possible. 3) In bpf_program__collect_reloc() step, we record the corresponding map, insn index, and relocation type for the global data. 4) And last but not least in the actual relocation step in bpf_program__relocate(), we mark the ldimm64 instruction with src_reg = BPF_PSEUDO_MAP_VALUE where in the first imm field the map's file descriptor is stored as similarly done as in BPF_PSEUDO_MAP_FD, and in the second imm field (as ldimm64 is 2-insn wide) we store the access offset into the section. Given these maps have only single element ldimm64's off remains zero in both parts. 5) On kernel side, this special marked BPF_PSEUDO_MAP_VALUE load will then store the actual target address in order to have a 'map-lookup'-free access. That is, the actual map value base address + offset. The destination register in the verifier will then be marked as PTR_TO_MAP_VALUE, containing the fixed offset as reg->off and backing BPF map as reg->map_ptr. Meaning, it's treated as any other normal map value from verification side, only with efficient, direct value access instead of actual call to map lookup helper as in the typical case. Currently, only support for static global variables has been added, and libbpf rejects non-static global variables from loading. This can be lifted until we have proper semantics for how BPF will treat multi-object BPF loads. From BTF side, libbpf will set the value type id of the types corresponding to the ".bss", ".data" and ".rodata" names which LLVM will emit without the object name prefix. The key type will be left as zero, thus making use of the key-less BTF option in array maps. Simple example dump of program using globals vars in each section: # bpftool prog [...] 6784: sched_cls name load_static_dat tag a7e1291567277844 gpl loaded_at 2019-03-11T15:39:34+0000 uid 0 xlated 1776B jited 993B memlock 4096B map_ids 2238,2237,2235,2236,2239,2240 # bpftool map show id 2237 2237: array name test_glo.bss flags 0x0 key 4B value 64B max_entries 1 memlock 4096B # bpftool map show id 2235 2235: array name test_glo.data flags 0x0 key 4B value 64B max_entries 1 memlock 4096B # bpftool map show id 2236 2236: array name test_glo.rodata flags 0x80 key 4B value 96B max_entries 1 memlock 4096B # bpftool prog dump xlated id 6784 int load_static_data(struct __sk_buff * skb): ; int load_static_data(struct __sk_buff *skb) 0: (b7) r6 = 0 ; test_reloc(number, 0, &num0); 1: (63) *(u32 *)(r10 -4) = r6 2: (bf) r2 = r10 ; int load_static_data(struct __sk_buff *skb) 3: (07) r2 += -4 ; test_reloc(number, 0, &num0); 4: (18) r1 = map[id:2238] 6: (18) r3 = map[id:2237][0]+0 <-- direct addr in .bss area 8: (b7) r4 = 0 9: (85) call array_map_update_elem#100464 10: (b7) r1 = 1 ; test_reloc(number, 1, &num1); [...] ; test_reloc(string, 2, str2); 120: (18) r8 = map[id:2237][0]+16 <-- same here at offset +16 122: (18) r1 = map[id:2239] 124: (18) r3 = map[id:2237][0]+16 126: (b7) r4 = 0 127: (85) call array_map_update_elem#100464 128: (b7) r1 = 120 ; str1[5] = 'x'; 129: (73) *(u8 *)(r9 +5) = r1 ; test_reloc(string, 3, str1); 130: (b7) r1 = 3 131: (63) *(u32 *)(r10 -4) = r1 132: (b7) r9 = 3 133: (bf) r2 = r10 ; int load_static_data(struct __sk_buff *skb) 134: (07) r2 += -4 ; test_reloc(string, 3, str1); 135: (18) r1 = map[id:2239] 137: (18) r3 = map[id:2235][0]+16 <-- direct addr in .data area 139: (b7) r4 = 0 140: (85) call array_map_update_elem#100464 141: (b7) r1 = 111 ; __builtin_memcpy(&str2[2], "hello", sizeof("hello")); 142: (73) *(u8 *)(r8 +6) = r1 <-- further access based on .bss data 143: (b7) r1 = 108 144: (73) *(u8 *)(r8 +5) = r1 [...] For Cilium use-case in particular, this enables migrating configuration constants from Cilium daemon's generated header defines into global data sections such that expensive runtime recompilations with LLVM can be avoided altogether. Instead, the ELF file becomes effectively a "template", meaning, it is compiled only once (!) and the Cilium daemon will then rewrite relevant configuration data from the ELF's .data or .rodata sections directly instead of recompiling the program. The updated ELF is then loaded into the kernel and atomically replaces the existing program in the networking datapath. More info in [0]. Based upon recent fix in LLVM, commit c0db6b6bd444 ("[BPF] Don't fail for static variables"). [0] LPC 2018, BPF track, "ELF relocation for static data in BPF", http://vger.kernel.org/lpc-bpf2018.html#session-3 Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Andrii Nakryiko <andriin@fb.com> Acked-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-04-10bpf, libbpf: refactor relocation handlingJoe Stringer1-30/+32
Adjust the code for relocations slightly with no functional changes, so that upcoming patches that will introduce support for relocations into the .data, .rodata and .bss sections can be added independent of these changes. Signed-off-by: Joe Stringer <joe@wand.net.nz> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Andrii Nakryiko <andriin@fb.com> Acked-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-04-07libbpf: Ignore -Wformat-nonliteral warningAndrey Ignatov1-0/+5
vsprintf() in __base_pr() uses nonliteral format string and it breaks compilation for those who provide corresponding extra CFLAGS, e.g.: https://github.com/libbpf/libbpf/issues/27 If libbpf is built with the flags from PR: libbpf.c:68:26: error: format string is not a string literal [-Werror,-Wformat-nonliteral] return vfprintf(stderr, format, args); ^~~~~~ 1 error generated. Ignore this warning since the use case in libbpf.c is legit. Signed-off-by: Andrey Ignatov <rdna@fb.com> Acked-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-04-04libbpf: teach libbpf about log_level bit 2Alexei Starovoitov4-4/+17
Allow bpf_prog_load_xattr() to specify log_level for program loading. Teach libbpf to accept log_level with bit 2 set. Increase default BPF_LOG_BUF_SIZE from 256k to 16M. There is no downside to increase it to a maximum allowed by old kernels. Existing 256k limit caused ENOSPC errors and users were not able to see verifier error which is printed at the end of the verifier log. If ENOSPC is hit, double the verifier log and try again to capture the verifier error. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-03-28tools/bpf: generate pkg-config file for libbpfLuca Boccassi3-3/+28
Generate a libbpf.pc file at build time so that users can rely on pkg-config to find the library, its CFLAGS and LDFLAGS. Signed-off-by: Luca Boccassi <bluca@debian.org> Acked-by: Andrey Ignatov <rdna@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-03-27Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds5-34/+88
Pull networking fixes from David Miller: "Fixes here and there, a couple new device IDs, as usual: 1) Fix BQL race in dpaa2-eth driver, from Ioana Ciornei. 2) Fix 64-bit division in iwlwifi, from Arnd Bergmann. 3) Fix documentation for some eBPF helpers, from Quentin Monnet. 4) Some UAPI bpf header sync with tools, also from Quentin Monnet. 5) Set descriptor ownership bit at the right time for jumbo frames in stmmac driver, from Aaro Koskinen. 6) Set IFF_UP properly in tun driver, from Eric Dumazet. 7) Fix load/store doubleword instruction generation in powerpc eBPF JIT, from Naveen N. Rao. 8) nla_nest_start() return value checks all over, from Kangjie Lu. 9) Fix asoc_id handling in SCTP after the SCTP_*_ASSOC changes this merge window. From Marcelo Ricardo Leitner and Xin Long. 10) Fix memory corruption with large MTUs in stmmac, from Aaro Koskinen. 11) Do not use ipv4 header for ipv6 flows in TCP and DCCP, from Eric Dumazet. 12) Fix topology subscription cancellation in tipc, from Erik Hugne. 13) Memory leak in genetlink error path, from Yue Haibing. 14) Valid control actions properly in packet scheduler, from Davide Caratti. 15) Even if we get EEXIST, we still need to rehash if a shrink was delayed. From Herbert Xu. 16) Fix interrupt mask handling in interrupt handler of r8169, from Heiner Kallweit. 17) Fix leak in ehea driver, from Wen Yang" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (168 commits) dpaa2-eth: fix race condition with bql frame accounting chelsio: use BUG() instead of BUG_ON(1) net: devlink: skip info_get op call if it is not defined in dumpit net: phy: bcm54xx: Encode link speed and activity into LEDs tipc: change to check tipc_own_id to return in tipc_net_stop net: usb: aqc111: Extend HWID table by QNAP device net: sched: Kconfig: update reference link for PIE net: dsa: qca8k: extend slave-bus implementations net: dsa: qca8k: remove leftover phy accessors dt-bindings: net: dsa: qca8k: support internal mdio-bus dt-bindings: net: dsa: qca8k: fix example net: phy: don't clear BMCR in genphy_soft_reset bpf, libbpf: clarify bump in libbpf version info bpf, libbpf: fix version info and add it to shared object rxrpc: avoid clang -Wuninitialized warning tipc: tipc clang warning net: sched: fix cleanup NULL pointer exception in act_mirr r8169: fix cable re-plugging issue net: ethernet: ti: fix possible object reference leak net: ibm: fix possible object reference leak ...
2019-03-25bpf, libbpf: clarify bump in libbpf version infoDaniel Borkmann1-0/+1
The current documentation suggests that we would need to bump the libbpf version on every change. Lets clarify this a bit more and reflect what we do today in practice, that is, bumping it once per development cycle. Fixes: 76d1b894c515 ("libbpf: Document API and ABI conventions") Reported-by: Stanislav Fomichev <sdf@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-03-25bpf, libbpf: fix version info and add it to shared objectDaniel Borkmann1-14/+28
Even though libbpf's versioning script for the linker (libbpf.map) is pointing to 0.0.2, the BPF_EXTRAVERSION in the Makefile has not been updated along with it and is therefore still on 0.0.1. While fixing up, I also noticed that the generated shared object versioning information is missing, typical convention is to have a linker name (libbpf.so), soname (libbpf.so.0) and real name (libbpf.so.0.0.2) for library management. This is based upon the LIBBPF_VERSION as well. The build will then produce the following bpf libraries: # ll libbpf* libbpf.a libbpf.so -> libbpf.so.0.0.2 libbpf.so.0 -> libbpf.so.0.0.2 libbpf.so.0.0.2 # readelf -d libbpf.so.0.0.2 | grep SONAME 0x000000000000000e (SONAME) Library soname: [libbpf.so.0] And install them accordingly: # rm -rf /tmp/bld; mkdir /tmp/bld; make -j$(nproc) O=/tmp/bld install Auto-detecting system features: ... libelf: [ on ] ... bpf: [ on ] CC /tmp/bld/libbpf.o CC /tmp/bld/bpf.o CC /tmp/bld/nlattr.o CC /tmp/bld/btf.o CC /tmp/bld/libbpf_errno.o CC /tmp/bld/str_error.o CC /tmp/bld/netlink.o CC /tmp/bld/bpf_prog_linfo.o CC /tmp/bld/libbpf_probes.o CC /tmp/bld/xsk.o LD /tmp/bld/libbpf-in.o LINK /tmp/bld/libbpf.a LINK /tmp/bld/libbpf.so.0.0.2 LINK /tmp/bld/test_libbpf INSTALL /tmp/bld/libbpf.a INSTALL /tmp/bld/libbpf.so.0.0.2 # ll /usr/local/lib64/libbpf.* /usr/local/lib64/libbpf.a /usr/local/lib64/libbpf.so -> libbpf.so.0.0.2 /usr/local/lib64/libbpf.so.0 -> libbpf.so.0.0.2 /usr/local/lib64/libbpf.so.0.0.2 Fixes: 1bf4b05810fe ("tools: bpftool: add probes for eBPF program types") Fixes: 1b76c13e4b36 ("bpf tools: Introduce 'bpf' library and add bpf feature check") Reported-by: Stanislav Fomichev <sdf@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-03-23Merge tag 'perf-core-for-mingo-5.1-20190321' of ↵Thomas Gleixner3-1/+318
git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent Pull perf/core improvements and fixes from Arnaldo: BPF: Song Liu: - Add support for annotating BPF programs, using the PERF_RECORD_BPF_EVENT and PERF_RECORD_KSYMBOL recently added to the kernel and plugging binutils's libopcodes disassembly of BPF programs with the existing annotation interfaces in 'perf annotate', 'perf report' and 'perf top' various output formats (--stdio, --stdio2, --tui). perf list: Andi Kleen: - Filter metrics when using substring search. perf record: Andi Kleen: - Allow to limit number of reported perf.data files - Clarify help for --switch-output. perf report: Andi Kleen - Indicate JITed code better. - Show all sort keys in help output. perf script: Andi Kleen: - Support relative time. perf stat: Andi Kleen: - Improve scaling. General: Changbin Du: - Fix some mostly error path memory and reference count leaks found using gcc's ASan and UBSan. Vendor events: Mamatha Inamdar: - Remove P8 HW events which are not supported. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2019-03-23Merge tag 'perf-core-for-mingo-5.1-20190311' of ↵Thomas Gleixner1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent Pull perf/core improvements and fixes from Arnaldo: kernel: Stephane Eranian : - Restore mmap record type correctly when handling PERF_RECORD_MMAP2 events, as the same template is used for all the threads interested in mmap events, some may want just PERF_RECORD_MMAP, while some may want the extra info in MMAP2 records. perf probe: Adrian Hunter: - Fix getting the kernel map, because since changes related to x86 PTI entry trampolines handling, there are more than one kernel map. perf script: Andi Kleen: - Support insn output for normal samples, i.e.: perf script -F ip,sym,insn --xed Will fetch the sample IP from the thread address space and feed it to Intel's XED disassembler, producing lines such as: ffffffffa4068804 native_write_msr wrmsr ffffffffa415b95e __hrtimer_next_event_base movq 0x18(%rax), %rdx That match 'perf annotate's output. - Make the --cpu filter apply to PERF_RECORD_COMM/FORK/... events, in addition to PERF_RECORD_SAMPLE. perf report: - Add a new --samples option to save a small random number of samples per hist entry, using a reservoir technique to select a representative number of samples. Then allow browsing the samples using 'perf script' as part of the hist entry context menu. This automatically adds the right filters, so only the thread or CPU of the sample is displayed. Then we use less' search functionality to directly jump to the time stamp of the selected sample. It uses different menus for assembler and source display. Assembler needs xed installed and source needs debuginfo. - Fix the UI browser scripts pop up menu when there are many scripts available. perf report: Andi Kleen: - Add 'time' sort option. E.g.: % perf report --sort time,overhead,symbol --time-quantum 1ms --stdio ... 0.67% 277061.87300 [.] _dl_start 0.50% 277061.87300 [.] f1 0.50% 277061.87300 [.] f2 0.33% 277061.87300 [.] main 0.29% 277061.87300 [.] _dl_lookup_symbol_x 0.29% 277061.87300 [.] dl_main 0.29% 277061.87300 [.] do_lookup_x 0.17% 277061.87300 [.] _dl_debug_initialize 0.17% 277061.87300 [.] _dl_init_paths 0.08% 277061.87300 [.] check_match 0.04% 277061.87300 [.] _dl_count_modids 1.33% 277061.87400 [.] f1 1.33% 277061.87400 [.] f2 1.33% 277061.87400 [.] main 1.17% 277061.87500 [.] main 1.08% 277061.87500 [.] f1 1.08% 277061.87500 [.] f2 1.00% 277061.87600 [.] main 0.83% 277061.87600 [.] f1 0.83% 277061.87600 [.] f2 1.00% 277061.87700 [.] main tools headers: Arnaldo Carvalho de Melo: - Update x86's syscall_64.tbl, no change in tools/perf behaviour. - Sync copies asm-generic/unistd.h and linux/in with the kernel sources. perf data: Jiri Olsa: - Prep work to support having perf.data stored as a directory, with one file per CPU, that ultimately will allow having one ring buffer reading thread per CPU. Vendor events: Martin Liška: - perf PMU events for AMD Family 17h. perf script python: Tony Jones: - Add python3 support for the remaining Intel PT related scripts, with these we should have a clean build of perf with python3 while still supporting the build with python2. libbpf: Arnaldo Carvalho de Melo: - Fix the build on uCLibc, adding the missing stdarg.h since we use va_list in one typedef. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-03-19tools lib bpf: Introduce bpf_program__get_prog_info_linear()Song Liu3-0/+317
Currently, bpf_prog_info includes 9 arrays. The user has the option to fetch any combination of these arrays. However, this requires a lot of handling. This work becomes more tricky when we need to store bpf_prog_info to a file, because these arrays are allocated independently. This patch introduces 'struct bpf_prog_info_linear', which stores arrays of bpf_prog_info in continuous memory. Helper functions are introduced to unify the work to get different sets of bpf_prog_info. Specifically, bpf_program__get_prog_info_linear() allows the user to select which arrays to fetch, and handles details for the user. Please see the comments right before 'enum bpf_prog_info_array' for more details and examples. Signed-off-by: Song Liu <songliubraving@fb.com> Reviewed-by: Jiri Olsa <jolsa@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lkml.kernel.org/r/ce92c091-e80d-a0c1-4aa0-987706c42b20@iogearbox.net Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: kernel-team@fb.com Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stanislav Fomichev <sdf@google.com> Link: http://lkml.kernel.org/r/20190312053051.2690567-3-songliubraving@fb.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-03-19perf tools: Fix errors under optimization level '-Og'Changbin Du1-1/+1
Optimization level '-Og' offers a reasonable level of optimization while maintaining fast compilation and a good debugging experience. This patch tries to make it work. $ make DEBUG=1 EXTRA_CFLAGS='-Og' bench/epoll-ctl.c: In function ‘do_threads’: bench/epoll-ctl.c:274:9: error: ‘ret’ may be used uninitialized in this function [-Werror=maybe-uninitialized] return ret; ^~~ ... Signed-off-by: Changbin Du <changbin.du@gmail.com> Reviewed-by: Jiri Olsa <jolsa@kernel.org> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt (VMware) <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/20190316080556.3075-4-changbin.du@gmail.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-03-14btf: resolve enum fwds in btf_dedupAndrii Nakryiko1-13/+38
GCC and clang support enum forward declarations as an extension. Such forward-declared enums will be represented as normal BTF_KIND_ENUM types with vlen=0. This patch adds ability to resolve such enums to their corresponding fully defined enums. This helps to avoid duplicated BTF type graphs which only differ by some types referencing forward-declared enum vs full enum. One such example in kernel is enum irqchip_irq_state, defined in include/linux/interrupt.h and forward-declared in include/linux/irq.h. This causes entire struct task_struct and all referenced types to be duplicated in btf_dedup output. This patch eliminates such duplication cases. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-03-12libbpf: fix to reject unknown flags in xsk_socket__create()Magnus Karlsson1-4/+11
In xsk_socket__create(), the libbpf_flags field was not checked for setting currently unused/unknown flags. This patch fixes that by returning -EINVAL if the user has set any flag that is not in use at this point in time. Fixes: 1cad07884239 ("libbpf: add support for using AF_XDP sockets") Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com> Reviewed-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-03-11tools lib bpf: Fix the build by adding a missing stdarg.h includeArnaldo Carvalho de Melo1-0/+1
The libbpf_print_fn_t typedef uses va_list without including the header where that type is defined, stdarg.h, breaking in places where we're unlucky for that type not to be already defined by some previously included header. Noticed while building on fedora 24 cross building tools/perf to the ARC architecture using the uClibc C library: 28 fedora:24-x-ARC-uClibc : FAIL arc-linux-gcc (ARCompact ISA Linux uClibc toolchain 2017.09-rc2) 7.1.1 20170710 CC /tmp/build/perf/tests/llvm.o In file included from tests/llvm.c:3:0: /git/linux/tools/lib/bpf/libbpf.h:57:20: error: unknown type name 'va_list' const char *, va_list ap); ^~~~~~~ /git/linux/tools/lib/bpf/libbpf.h:59:34: error: unknown type name 'libbpf_print_fn_t' LIBBPF_API void libbpf_set_print(libbpf_print_fn_t fn); ^~~~~~~~~~~~~~~~~ mv: cannot stat '/tmp/build/perf/tests/.llvm.o.tmp': No such file or directory Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Jakub Kicinski <jakub.kicinski@netronome.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Quentin Monnet <quentin.monnet@netronome.com> Cc: Stanislav Fomichev <sdf@google.com> Cc: Yonghong Song <yhs@fb.com> Fixes: a8a1f7d09cfc ("libbpf: fix libbpf_print") Link: https://lkml.kernel.org/n/tip-5270n2quu2gqz22o7itfdx00@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-03-11libbpf: handle BTF parsing and loading properlyAndrii Nakryiko1-3/+10
This patch splits and cleans up error handling logic for loading BTF data. Previously, if BTF data was parsed successfully, but failed to load into kernel, we'd report nonsensical error code, instead of error returned from btf__load(). Now btf__new() and btf__load() are handled separately with proper cleanup and warning reporting. Fixes: d29d87f7e612 ("btf: separate btf creation and loading") Reported-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Andrii Nakryiko <andriin@fb.com> Acked-by: Martin KaFai Lau <kafai@fb.com> Acked-by: Yonghong Song <yhs@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-03-08bpf, libbpf: fixing leak when kernel does not support btfNikita V. Shirokov1-0/+2
We could end up in situation when we have object file w/ all btf info, but kernel does not support btf yet. In this situation currently libbpf just set obj->btf to NULL w/o freeing it first. This patch is fixing it by making sure to run btf__free first. Fixes: d29d87f7e612 ("btf: separate btf creation and loading") Signed-off-by: Nikita V. Shirokov <tehnerd@tehnerd.com> Acked-by: Yonghong Song <yhs@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-03-07libbpf: force fixdep compilation at the start of the buildStanislav Fomichev1-1/+2
libbpf targets don't explicitly depend on fixdep target, so when we do 'make -j$(nproc)', there is a high probability, that some objects will be built before fixdep binary is available. Fix this by running sub-make; this makes sure that fixdep dependency is properly accounted for. For the same issue in perf, see commit abb26210a395 ("perf tools: Force fixdep compilation at the start of the build"). Before: $ rm -rf /tmp/bld; mkdir /tmp/bld; make -j$(nproc) O=/tmp/bld -C tools/lib/bpf/ Auto-detecting system features: ... libelf: [ on ] ... bpf: [ on ] HOSTCC /tmp/bld/fixdep.o CC /tmp/bld/libbpf.o CC /tmp/bld/bpf.o CC /tmp/bld/btf.o CC /tmp/bld/nlattr.o CC /tmp/bld/libbpf_errno.o CC /tmp/bld/str_error.o CC /tmp/bld/netlink.o CC /tmp/bld/bpf_prog_linfo.o CC /tmp/bld/libbpf_probes.o CC /tmp/bld/xsk.o HOSTLD /tmp/bld/fixdep-in.o LINK /tmp/bld/fixdep LD /tmp/bld/libbpf-in.o LINK /tmp/bld/libbpf.a LINK /tmp/bld/libbpf.so LINK /tmp/bld/test_libbpf $ head /tmp/bld/.libbpf.o.cmd # cannot find fixdep (/usr/local/google/home/sdf/src/linux/xxx//fixdep) # using basic dep data /tmp/bld/libbpf.o: libbpf.c /usr/include/stdc-predef.h \ /usr/include/stdlib.h /usr/include/features.h \ /usr/include/x86_64-linux-gnu/sys/cdefs.h \ /usr/include/x86_64-linux-gnu/bits/wordsize.h \ /usr/include/x86_64-linux-gnu/gnu/stubs.h \ /usr/include/x86_64-linux-gnu/gnu/stubs-64.h \ /usr/lib/gcc/x86_64-linux-gnu/7/include/stddef.h \ After: $ rm -rf /tmp/bld; mkdir /tmp/bld; make -j$(nproc) O=/tmp/bld -C tools/lib/bpf/ Auto-detecting system features: ... libelf: [ on ] ... bpf: [ on ] HOSTCC /tmp/bld/fixdep.o HOSTLD /tmp/bld/fixdep-in.o LINK /tmp/bld/fixdep CC /tmp/bld/libbpf.o CC /tmp/bld/bpf.o CC /tmp/bld/nlattr.o CC /tmp/bld/btf.o CC /tmp/bld/libbpf_errno.o CC /tmp/bld/str_error.o CC /tmp/bld/netlink.o CC /tmp/bld/bpf_prog_linfo.o CC /tmp/bld/libbpf_probes.o CC /tmp/bld/xsk.o LD /tmp/bld/libbpf-in.o LINK /tmp/bld/libbpf.a LINK /tmp/bld/libbpf.so LINK /tmp/bld/test_libbpf $ head /tmp/bld/.libbpf.o.cmd cmd_/tmp/bld/libbpf.o := gcc -Wp,-MD,/tmp/bld/.libbpf.o.d -Wp,-MT,/tmp/bld/libbpf.o -g -Wall -DHAVE_LIBELF_MMAP_SUPPORT -DCOMPAT_NEED_REALLOCARRAY -Wbad-function-cast -Wdeclaration-after-statement -Wformat-security -Wformat-y2k -Winit-self -Wmissing-declarations -Wmissing-prototypes -Wnested-externs -Wno-system-headers -Wold-style-definition -Wpacked -Wredundant-decls -Wshadow -Wstrict-prototypes -Wswitch-default -Wswitch-enum -Wundef -Wwrite-strings -Wformat -Wstrict-aliasing=3 -Werror -Wall -fPIC -I. -I/usr/local/google/home/sdf/src/linux/tools/include -I/usr/local/google/home/sdf/src/linux/tools/arch/x86/include/uapi -I/usr/local/google/home/sdf/src/linux/tools/include/uapi -fvisibility=hidden -D"BUILD_STR(s)=$(pound)s" -c -o /tmp/bld/libbpf.o libbpf.c source_/tmp/bld/libbpf.o := libbpf.c deps_/tmp/bld/libbpf.o := \ /usr/include/stdc-predef.h \ /usr/include/stdlib.h \ /usr/include/features.h \ /usr/include/x86_64-linux-gnu/sys/cdefs.h \ /usr/include/x86_64-linux-gnu/bits/wordsize.h \ Fixes: 7c422f557266 ("tools build: Build fixdep helper from perf and basic libs") Reported-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Stanislav Fomichev <sdf@google.com> Acked-by: Yonghong Song <yhs@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-03-01btf: fix bug with resolving STRUCT/UNION into corresponding FWDAndrii Nakryiko1-3/+17
When checking available canonical candidates for struct/union algorithm utilizes btf_dedup_is_equiv to determine if candidate is suitable. This check is not enough when candidate is corresponding FWD for that struct/union, because according to equivalence logic they are equivalent. When it so happens that FWD and STRUCT/UNION end in hashing to the same bucket, it's possible to create remapping loop from FWD to STRUCT and STRUCT to same FWD, which will cause btf_dedup() to loop forever. This patch fixes the issue by additionally checking that type and canonical candidate are strictly equal (utilizing btf_equal_struct). Fixes: d5caef5b5655 ("btf: add BTF types deduplication algorithm") Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Andrii Nakryiko <andriin@fb.com> Acked-by: Song Liu <songliubraving@fb.com> Acked-by: Yonghong Song <yhs@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-03-01btf: allow to customize dedup hash table sizeAndrii Nakryiko2-17/+37
Default size of dedup table (16k) is good enough for most binaries, even typical vmlinux images. But there are cases of binaries with huge amount of BTF types (e.g., allyesconfig variants of kernel), which benefit from having bigger dedup table size to lower amount of unnecessary hash collisions. Tools like pahole, thus, can tune this parameter to reach optimal performance. This change also serves double purpose of allowing tests to force hash collisions to test some corner cases, used in follow up patch. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Acked-by: Yonghong Song <yhs@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-03-01libbpf: fix formatting for btf_ext__get_raw_dataAndrii Nakryiko1-1/+1
Fix invalid formatting of pointer arg. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-03-01tools/libbpf: signedness bug in btf_dedup_ref_type()Dan Carpenter1-1/+2
The "ref_type_id" variable needs to be signed for the error handling to work. Fixes: d5caef5b5655 ("btf: add BTF types deduplication algorithm") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Andrii Nakryiko <andriin@fb.com> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-03-01tools: libbpf: make sure readelf shows full names in build checksJakub Kicinski1-2/+2
readelf truncates its output by default to attempt to make it more readable. This can lead to function names getting aliased if they differ late in the string. Use --wide parameter to avoid truncation. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Acked-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-03-01tools: libbpf: add a correctly named define for map iterationJakub Kicinski2-5/+6
For historical reasons the helper to loop over maps in an object is called bpf_map__for_each while it really should be called bpf_object__for_each_map. Rename and add a correctly named define for backward compatibility. Switch all in-tree users to the correct name (Quentin). Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-02-26libbpf: add support for using AF_XDP socketsMagnus Karlsson6-3/+951
This commit adds AF_XDP support to libbpf. The main reason for this is to facilitate writing applications that use AF_XDP by offering higher-level APIs that hide many of the details of the AF_XDP uapi. This is in the same vein as libbpf facilitates XDP adoption by offering easy-to-use higher level interfaces of XDP functionality. Hopefully this will facilitate adoption of AF_XDP, make applications using it simpler and smaller, and finally also make it possible for applications to benefit from optimizations in the AF_XDP user space access code. Previously, people just copied and pasted the code from the sample application into their application, which is not desirable. The interface is composed of two parts: * Low-level access interface to the four rings and the packet * High-level control plane interface for creating and setting up umems and af_xdp sockets as well as a simple XDP program. Tested-by: Björn Töpel <bjorn.topel@intel.com> Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-02-17tools/libbpf: support bigger BTF data sizesAndrii Nakryiko1-7/+8
While it's understandable why kernel limits number of BTF types to 65535 and size of string section to 64KB, in libbpf as user-space library it's too restrictive. E.g., pahole converting DWARF to BTF type information for Linux kernel generates more than 3 million BTF types and more than 3MB of strings, before deduplication. So to allow btf__dedup() to do its work, we need to be able to load bigger BTF sections using btf__new(). Singed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-02-15libbpf: Introduce bpf_object__btfAndrey Ignatov3-0/+9
Add new accessor for bpf_object to get opaque struct btf * from it. struct btf * is needed for all operations with BTF and it's present in bpf_object. The only thing missing is a way to get it. Example use-case is to get BTF key_type_id and value_type_id for a map in bpf_object. It can be done with btf__get_map_kv_tids() but that function requires struct btf *. Similar API can be added for struct btf_ext but no use-case for it yet. Signed-off-by: Andrey Ignatov <rdna@fb.com> Acked-by: Yonghong Song <yhs@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-02-15libbpf: Introduce bpf_map__resizeAndrey Ignatov3-0/+16
Add bpf_map__resize() to change max_entries for a map. Quite often necessary map size is unknown at compile time and can be calculated only at run time. Currently the following approach is used to do so: * bpf_object__open_buffer() to open Elf file from a buffer; * bpf_object__find_map_by_name() to find relevant map; * bpf_map__def() to get map attributes and create struct bpf_create_map_attr from them; * update max_entries in bpf_create_map_attr; * bpf_create_map_xattr() to create new map with updated max_entries; * bpf_map__reuse_fd() to replace the map in bpf_object with newly created one. And after all this bpf_object can finally be loaded. The map will have new size. It 1) is quite a lot of steps; 2) doesn't take BTF into account. For "2)" even more steps should be made and some of them require changes to libbpf (e.g. to get struct btf * from bpf_object). Instead the whole problem can be solved by introducing simple bpf_map__resize() API that checks the map and sets new max_entries if the map is not loaded yet. So the new steps are: * bpf_object__open_buffer() to open Elf file from a buffer; * bpf_object__find_map_by_name() to find relevant map; * bpf_map__resize() to update max_entries. That's much simpler and works with BTF. Signed-off-by: Andrey Ignatov <rdna@fb.com> Acked-by: Yonghong Song <yhs@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-02-15tools/bpf: replace bzero with memsetAndrii Nakryiko3-30/+28
bzero() call is deprecated and superseded by memset(). Signed-off-by: Andrii Nakryiko <andriin@fb.com> Reported-by: David Laight <david.laight@aculab.com> Acked-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-02-08tools/bpf: remove btf__get_strings() superseded by raw data APIAndrii Nakryiko3-10/+0
Now that we have btf__get_raw_data() it's trivial for tests to iterate over all strings for testing purposes, which eliminates the need for btf__get_strings() API. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Acked-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-02-08btf: expose API to work with raw btf_ext dataAndrii Nakryiko3-48/+57
This patch changes struct btf_ext to retain original data in sequential block of memory, which makes it possible to expose btf_ext__get_raw_data() interface similar to btf__get_raw_data(), allowing users of libbpf to get access to raw representation of .BTF.ext section. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Acked-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-02-08btf: expose API to work with raw btf dataAndrii Nakryiko3-0/+8
This patch exposes new API btf__get_raw_data() that allows to get a copy of raw BTF data out of struct btf. This is useful for external programs that need to manipulate raw data, e.g., pahole using btf__dedup() to deduplicate BTF type info and then writing it back to file. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-02-08btf: separate btf creation and loadingAndrii Nakryiko4-25/+33
This change splits out previous btf__new functionality of constructing struct btf and loading it into kernel into two: - btf__new() just creates and initializes struct btf - btf__load() attempts to load existing struct btf into kernel btf__free will still close BTF fd, if it was ever loaded successfully into kernel. This change allows users of libbpf to manipulate BTF using its API, without the need to unnecessarily load it into kernel. One of the intended use cases is pahole, which will do DWARF to BTF conversion and then use libbpf to do type deduplication, while then handling ELF sections overwriting and other concerns on its own. Fixes: 2d3feca8c44f ("bpf: btf: print map dump and lookup with btf info") Signed-off-by: Andrii Nakryiko <andriin@fb.com> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-02-08tools/bpf: add log_level to bpf_load_program_attrYonghong Song2-5/+18
The kernel verifier has three levels of logs: 0: no logs 1: logs mostly useful > 1: verbose Current libbpf API functions bpf_load_program_xattr() and bpf_load_program() cannot specify log_level. The bcc, however, provides an interface for user to specify log_level 2 for verbose output. This patch added log_level into structure bpf_load_program_attr, so users, including bcc, can use bpf_load_program_xattr() to change log_level. The supported log_level is 0, 1, and 2. The bpf selftest test_sock.c is modified to enable log_level = 2. If the "verbose" in test_sock.c is changed to true, the test will output logs like below: $ ./test_sock func#0 @0 0: R1=ctx(id=0,off=0,imm=0) R10=fp0,call_-1 0: (bf) r6 = r1 1: R1=ctx(id=0,off=0,imm=0) R6_w=ctx(id=0,off=0,imm=0) R10=fp0,call_-1 1: (61) r7 = *(u32 *)(r6 +28) invalid bpf_context access off=28 size=4 Test case: bind4 load with invalid access: src_ip6 .. [PASS] ... Test case: bind6 allow all .. [PASS] Summary: 16 PASSED, 0 FAILED Some test_sock tests are negative tests and verbose verifier log will be printed out as shown in the above. Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-02-08tools/bpf: add missing strings.h includeAndrii Nakryiko3-0/+3
Few files in libbpf are using bzero() function (defined in strings.h header), but don't include corresponding header. When libbpf is added as a dependency to pahole, this undeterministically causes warnings on some machines: bpf.c:225:2: warning: implicit declaration of function 'bzero' [-Wimplicit-function-declaration] bzero(&attr, sizeof(attr)); ^~~~~ Signed-off-by: Andrii Nakryiko <andriin@fb.com> Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-02-06tools/bpf: silence a libbpf unnecessary warningYonghong Song1-2/+2
Commit 96408c43447a ("tools/bpf: implement libbpf btf__get_map_kv_tids() API function") refactored function bpf_map_find_btf_info() and moved bulk of implementation into btf.c as btf__get_map_kv_tids(). This change introduced a bug such that test_btf will print out the following warning although the test passed: BTF libbpf test[2] (test_btf_nokv.o): libbpf: map:btf_map container_name:____btf_map_btf_map cannot be found in BTF. Missing BPF_ANNOTATE_KV_PAIR? Previously, the error message is guarded with pr_debug(). Commit 96408c43447a changed it to pr_warning() and hence caused the warning. Restoring to pr_debug() for the message fixed the issue. Fixes: 96408c43447a ("tools/bpf: implement libbpf btf__get_map_kv_tids() API function") Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-02-06tools/bpf: add const qualifier to btf__get_map_kv_tids() map_name parameterYonghong Song2-2/+2
Commit 96408c43447a ("tools/bpf: implement libbpf btf__get_map_kv_tids() API function") added the API function btf__get_map_kv_tids(): btf__get_map_kv_tids(const struct btf *btf, char *map_name, ...) The parameter map_name has type "char *". This is okay inside libbpf library since the map_name is from bpf_map->name which also has type "char *". This will be problematic if the caller for map_name already has attribute "const", e.g., from C++ string.c_str(). It will result in either a warning or an error. /home/yhs/work/bcc/src/cc/btf.cc:166:51: error: invalid conversion from ‘const char*’ to ‘char*’ [-fpermissive] return btf__get_map_kv_tids(btf_, map_name.c_str() This patch added "const" attributes to map_name parameter. Fixes: 96408c43447a ("tools/bpf: implement libbpf btf__get_map_kv_tids() API function") Signed-off-by: Yonghong Song <yhs@fb.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-02-05selftests/btf: add initial BTF dedup testsAndrii Nakryiko3-0/+17
This patch sets up a new kind of tests (BTF dedup tests) and tests few aspects of BTF dedup algorithm. More complete set of tests will come in follow up patches. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-02-05btf: add BTF types deduplication algorithmAndrii Nakryiko3-0/+1749
This patch implements BTF types deduplication algorithm. It allows to greatly compress typical output of pahole's DWARF-to-BTF conversion or LLVM's compilation output by detecting and collapsing identical types emitted in isolation per compilation unit. Algorithm also resolves struct/union forward declarations into concrete BTF types representing referenced struct/union. If undesired, this resolution can be disabled through specifying corresponding options. Algorithm itself and its application to Linux kernel's BTF types is described in details at: https://facebookmicrosites.github.io/bpf/blog/2018/11/14/btf-enhancement.html Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-02-05btf: extract BTF type size calculationAndrii Nakryiko1-52/+46
This pre-patch extracts calculation of amount of space taken by BTF type descriptor for later reuse by btf_dedup functionality. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-02-05libbpf: fix libbpf_printStanislav Fomichev2-12/+5
With the recent print rework we now have the following problem: pr_{warning,info,debug} expand to __pr which calls libbpf_print. libbpf_print does va_start and calls __libbpf_pr with va_list argument. In __base_pr we again do va_start. Because the next argument is a va_list, we don't get correct pointer to the argument (and print noting in my case, I don't know why it doesn't crash tbh). Fix this by changing libbpf_print_fn_t signature to accept va_list and remove unneeded calls to va_start in the existing users. Alternatively, this can we solved by exporting __libbpf_pr and changing __pr macro to (and killing libbpf_print): { if (__libbpf_pr) __libbpf_pr(level, "libbpf: " fmt, ##__VA_ARGS__) } Signed-off-by: Stanislav Fomichev <sdf@google.com> Acked-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-02-04tools/bpf: implement libbpf btf__get_map_kv_tids() API functionYonghong Song4-63/+87
Currently, to get map key/value type id's, the macro BPF_ANNOTATE_KV_PAIR(<map_name>, <key_type>, <value_type>) needs to be defined in the bpf program for the corresponding map. During program/map loading time, the local static function bpf_map_find_btf_info() in libbpf.c is implemented to retrieve the key/value type ids given the map name. The patch refactored function bpf_map_find_btf_info() to create an API btf__get_map_kv_tids() which includes the bulk of implementation for the original function. The API btf__get_map_kv_tids() can be used by bcc, a JIT based bpf compilation system, which uses the same BPF_ANNOTATE_KV_PAIR to record map key/value types. Acked-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-02-04tools/bpf: expose functions btf_ext__* as API functionsYonghong Song2-12/+18
The following set of functions, which manipulates .BTF.ext section, are exposed as API functions: . btf_ext__new . btf_ext__free . btf_ext__reloc_func_info . btf_ext__reloc_line_info . btf_ext__func_info_rec_size . btf_ext__line_info_rec_size These functions are useful for JIT based bpf codegen, e.g., bcc, to manipulate in-memory .BTF.ext sections. The signature of function btf_ext__reloc_func_info() is also changed to be the same as its definition in btf.c. Acked-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-02-04tools/bpf: simplify libbpf API function libbpf_set_print()Yonghong Song3-32/+17
Currently, the libbpf API function libbpf_set_print() takes three function pointer parameters for warning, info and debug printout respectively. This patch changes the API to have just one function pointer parameter and the function pointer has one additional parameter "debugging level". So if in the future, if the debug level is increased, the function signature won't change. Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-02-04tools/bpf: print out btf log at LIBBPF_WARN levelYonghong Song3-22/+9
Currently, the btf log is allocated and printed out in case of error at LIBBPF_DEBUG level. Such logs from kernel are very important for debugging. For example, bpf syscall BPF_PROG_LOAD command can get verifier logs back to user space. In function load_program() of libbpf.c, the log buffer is allocated unconditionally and printed out at pr_warning() level. Let us do the similar thing here for btf. Allocate buffer unconditionally and print out error logs at pr_warning() level. This can reduce one global function and optimize for common situations where pr_warning() is activated either by default or by user supplied debug output function. Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-02-04tools/bpf: move libbpf pr_* debug print functions to headersYonghong Song6-70/+120
A global function libbpf_print, which is invisible outside the shared library, is defined to print based on levels. The pr_warning, pr_info and pr_debug macros are moved into the newly created header common.h. So any .c file including common.h can use these macros directly. Currently btf__new and btf_ext__new API has an argument getting __pr_debug function pointer into btf.c so the debugging information can be printed there. This patch removed this parameter from btf__new and btf_ext__new and directly using pr_debug in btf.c. Another global function libbpf_print_level_available, also invisible outside the shared library, can test whether a particular level debug printing is available or not. It is used in btf.c to test whether DEBUG level debug printing is availabl or not, based on which the log buffer will be allocated when loading btf to the kernel. Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-02-02libbpf: Add a support for getting xdp prog id on ifindexMaciej Fijalkowski3-0/+87
Since we have a dedicated netlink attributes for xdp setup on a particular interface, it is now possible to retrieve the program id that is currently attached to the interface. The use case is targeted for sample xdp programs, which will store the program id just after loading bpf program onto iface. On shutdown, the sample will make sure that it can unload the program by querying again the iface and verifying that both program id's matches. Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-02-02libbpf: Add a helper for retrieving a map fd for a given nameMaciej Fijalkowski3-0/+10
XDP samples are mostly cooperating with eBPF maps through their file descriptors. In case of a eBPF program that contains multiple maps it might be tiresome to iterate through them and call bpf_map__fd for each one. Add a helper mostly based on bpf_object__find_map_by_name, but instead of returning the struct bpf_map pointer, return map fd. Suggested-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-02-01libbpf: introduce bpf_map_lookup_elem_flags()Alexei Starovoitov3-0/+16
Introduce int bpf_map_lookup_elem_flags(int fd, const void *key, void *value, __u64 flags) helper to lookup array/hash/cgroup_local_storage elements with BPF_F_LOCK flag. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>