- 15 Dec, 2019 11 commits
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Andrii Nakryiko authored
Expose BTF API that calculates type alignment requirements. Signed-off-by:
Andrii Nakryiko <andriin@fb.com> Signed-off-by:
Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20191214014341.3442258-7-andriin@fb.com
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Andrii Nakryiko authored
LIBBPF_API and DECLARE_LIBBPF_OPTS are needed in many public libbpf API headers. Extract them into libbpf_common.h to avoid unnecessary interdependency between btf.h, libbpf.h, and bpf.h or code duplication. Signed-off-by:
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Andrii Nakryiko authored
Add a convenience macro BPF_EMBED_OBJ, which allows to embed other files (typically used to embed BPF .o files) into a hosting userspace programs. To C program it is exposed as struct bpf_embed_data, containing a pointer to raw data and its size in bytes. Signed-off-by:
Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/bpf/20191214014341.3442258-5-andriin@fb.com
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Andrii Nakryiko authored
Few libbpf APIs are not public but currently exposed through libbpf.h to be used by bpftool. Move them to libbpf_internal.h, where intent of being non-stable and non-public is much more obvious. Signed-off-by:
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Andrii Nakryiko authored
Generalize BPF program attaching and allow libbpf to auto-detect type (and extra parameters, where applicable) and attach supported BPF program types based on program sections. Currently this is supported for: - kprobe/kretprobe; - tracepoint; - raw tracepoint; - tracing programs (typed raw TP/fentry/fexit). More types support can be trivially added within this framework. Signed-off-by:
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Andrii Nakryiko authored
Reorganize bpf_object__open and bpf_object__load steps such that bpf_object__open doesn't need root access. This was previously done for feature probing and BTF sanitization. This doesn't have to happen on open, though, so move all those steps into the load phase. This is important, because it makes it possible for tools like bpftool, to just open BPF object file and inspect their contents: programs, maps, BTF, etc. For such operations it is prohibitive to require root access. On the other hand, there is a lot of custom libbpf logic in those steps, so its best avoided for tools to reimplement all that on their own. Signed-off-by:
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Thadeu Lima de Souza Cascardo authored
Fedora binutils has been patched to show "other info" for a symbol at the end of the line. This was done in order to support unmaintained scripts that would break with the extra info. [1] [1] https://src.fedoraproject.org/rpms/binutils/c/b8265c46f7ddae23a792ee8306fbaaeacba83bf8 This in turn has been done to fix the build of ruby, because of checksec. [2] Thanks Michael Ellerman for the pointer. [2] https://bugzilla.redhat.com/show_bug.cgi?id=1479302 As libbpf Makefile is not unmaintained, we can simply deal with either output format, by just removing the "other info" field, as it always comes inside brackets. Fixes: 3464afdf (libbpf: Fix readelf output parsing on powerpc with recent binutils) Reported-by:
Justin Forbes <jmforbes@linuxtx.org> Signed-off-by:
Thadeu Lima de Souza Cascardo <cascardo@canonical.com> Signed-off-by:
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Alexei Starovoitov authored
Paul Chaignon says: ==================== When working with frequently modified BPF programs, both the ID and the tag may change. bpftool currently doesn't provide a "stable" way to match such programs. This patchset allows bpftool to match programs and maps by name. When given a tag that matches several programs, bpftool currently only considers the first match. The first patch changes that behavior to either process all matching programs (for the show and dump commands) or error out. The second patch implements program lookup by name, with the same behavior as for tags in case of ambiguity. The last patch implements map lookup by name. Changelogs: Changes in v2: - Fix buffer overflow after realloc. - Add example output to commit message. - Properly close JSON arrays on errors. - Fix style errors (line breaks, for loops, exit labels, type for tagname). - Move do_show code for argc == 2 to do_show_subset functions. - Rebase. ==================== Signed-off-by: -
Paul Chaignon authored
This patch implements lookup by name for maps and changes the behavior of lookups by tag to be consistent with prog subcommands. Similarly to program subcommands, the show and dump commands will return all maps with the given name (or tag), whereas other commands will error out if several maps have the same name (resp. tag). When a map has BTF info, it is dumped in JSON with available BTF info. This patch requires that all matched maps have BTF info before switching the output format to JSON. Signed-off-by:
Paul Chaignon <paul.chaignon@orange.com> Signed-off-by:
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Paul Chaignon authored
When working with frequently modified BPF programs, both the ID and the tag may change. bpftool currently doesn't provide a "stable" way to match such programs. This patch implements lookup by name for programs. The show and dump commands will return all programs with the given name, whereas other commands will error out if several programs have the same name. Signed-off-by:
Quentin Monnet <quentin.monnet@netronome.com> Link: https://lore.kernel.org/bpf/b5fc1a5dcfaeb5f16fc80295cdaa606dd2d91534.1576263640.git.paul.chaignon@gmail.com
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Paul Chaignon authored
When several BPF programs have the same tag, bpftool matches only the first (in ID order). This patch changes that behavior such that dump and show commands return all matched programs. Commands that require a single program (e.g., pin and attach) will error out if given a tag that matches several. bpftool prog dump will also error out if file or visual are given and several programs have the given tag. In the case of the dump command, a program header is added before each dump only if the tag matches several programs; this patch doesn't change the output if a single program matches. The output when several programs match thus looks as follows. $ ./bpftool prog dump xlated tag 6deef7357e7b4530 3: cgroup_skb tag 6deef7357e7b4530 gpl 0: (bf) r6 = r1 [...] 7: (95) exit 4: cgroup_skb tag 6deef7357e7b4530 gpl 0: (bf) r6 = r1 [...] 7: (95) exit Signed-off-by:
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- 13 Dec, 2019 24 commits
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Stanislav Fomichev authored
Make sure we can pass arbitrary data in wire_len/gso_segs. Signed-off-by:
Stanislav Fomichev <sdf@google.com> Signed-off-by:
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Stanislav Fomichev authored
wire_len should not be less than real len and is capped by GSO_MAX_SIZE. gso_segs is capped by GSO_MAX_SEGS. v2: * set wire_len to skb->len when passed wire_len is 0 (Alexei Starovoitov) Signed-off-by:
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Alexei Starovoitov authored
Björn Töpel says: ==================== Overview ======== This is the 6th iteration of the series that introduces the BPF dispatcher, which is a mechanism to avoid indirect calls. The BPF dispatcher is a multi-way branch code generator, targeted for BPF programs. E.g. when an XDP program is executed via the bpf_prog_run_xdp(), it is invoked via an indirect call. With retpolines enabled, the indirect call has a substantial performance impact. The dispatcher is a mechanism that transform indirect calls to direct calls, and therefore avoids the retpoline. The dispatcher is generated using the BPF JIT, and relies on text poking provided by bpf_arch_text_poke(). The dispatcher hijacks a trampoline function it via the __fentry__ nop of the trampoline. One dispatcher instance currently supports up to 48 dispatch points. This can be extended in the future. In this series, only one dispatcher instance is supported, and the only user is XDP. The dispatcher is updated when an XDP program is attached/detached to/from a netdev. An alternative to this could have been to update the dispatcher at program load point, but as there are usually more XDP programs loaded than attached, so the latter was picked. The XDP dispatcher is always enabled, if available, because it helps even when retpolines are disabled. Please refer to the "Performance" section below. The first patch refactors the image allocation from the BPF trampoline code. Patch two introduces the dispatcher, and patch three adds a dispatcher for XDP, and wires up the XDP control-/ fast-path. Patch four adds the dispatcher to BPF_TEST_RUN. Patch five adds a simple selftest, and the last adds alignment to jump targets. I have rebased the series on commit 679152d3 ("libbpf: Fix printf compilation warnings on ppc64le arch"). Generated code, x86-64 ====================== The dispatcher currently has a maximum of 48 entries, where one entry is a unique BPF program. Multiple users of a dispatcher instance using the same BPF program will share that entry. The program/slot lookup is performed by a binary search, O(log n). Let's have a look at the generated code. The trampoline function has the following signature: unsigned int tramp(const void *ctx, const struct bpf_insn *insnsi, unsigned int (*bpf_func)(const void *, const struct bpf_insn *)) On Intel x86-64 this means that rdx will contain the bpf_func. To, make it easier to read, I've let the BPF programs have the following range: 0xffffffffffffffff (-1) to 0xfffffffffffffff0 (-16). 0xffffffff81c00f10 is the retpoline thunk, in this case __x86_indirect_thunk_rdx. If retpolines are disabled the thunk will be a regular indirect call. The minimal dispatcher will then look like this: ffffffffc0002000: cmp rdx,0xffffffffffffffff ffffffffc0002007: je 0xffffffffffffffff ; -1 ffffffffc000200d: jmp 0xffffffff81c00f10 A 16 entry dispatcher looks like this: ffffffffc0020000: cmp rdx,0xfffffffffffffff7 ; -9 ffffffffc0020007: jg 0xffffffffc0020130 ffffffffc002000d: cmp rdx,0xfffffffffffffff3 ; -13 ffffffffc0020014: jg 0xffffffffc00200a0 ffffffffc002001a: cmp rdx,0xfffffffffffffff1 ; -15 ffffffffc0020021: jg 0xffffffffc0020060 ffffffffc0020023: cmp rdx,0xfffffffffffffff0 ; -16 ffffffffc002002a: jg 0xffffffffc0020040 ffffffffc002002c: cmp rdx,0xfffffffffffffff0 ; -16 ffffffffc0020033: je 0xfffffffffffffff0 ; -16 ffffffffc0020039: jmp 0xffffffff81c00f10 ffffffffc002003e: xchg ax,ax ffffffffc0020040: cmp rdx,0xfffffffffffffff1 ; -15 ffffffffc0020047: je 0xfffffffffffffff1 ; -15 ffffffffc002004d: jmp 0xffffffff81c00f10 ffffffffc0020052: nop DWORD PTR [rax+rax*1+0x0] ffffffffc002005a: nop WORD PTR [rax+rax*1+0x0] ffffffffc0020060: cmp rdx,0xfffffffffffffff2 ; -14 ffffffffc0020067: jg 0xffffffffc0020080 ffffffffc0020069: cmp rdx,0xfffffffffffffff2 ; -14 ffffffffc0020070: je 0xfffffffffffffff2 ; -14 ffffffffc0020076: jmp 0xffffffff81c00f10 ffffffffc002007b: nop DWORD PTR [rax+rax*1+0x0] ffffffffc0020080: cmp rdx,0xfffffffffffffff3 ; -13 ffffffffc0020087: je 0xfffffffffffffff3 ; -13 ffffffffc002008d: jmp 0xffffffff81c00f10 ffffffffc0020092: nop DWORD PTR [rax+rax*1+0x0] ffffffffc002009a: nop WORD PTR [rax+rax*1+0x0] ffffffffc00200a0: cmp rdx,0xfffffffffffffff5 ; -11 ffffffffc00200a7: jg 0xffffffffc00200f0 ffffffffc00200a9: cmp rdx,0xfffffffffffffff4 ; -12 ffffffffc00200b0: jg 0xffffffffc00200d0 ffffffffc00200b2: cmp rdx,0xfffffffffffffff4 ; -12 ffffffffc00200b9: je 0xfffffffffffffff4 ; -12 ffffffffc00200bf: jmp 0xffffffff81c00f10 ffffffffc00200c4: nop DWORD PTR [rax+rax*1+0x0] ffffffffc00200cc: nop DWORD PTR [rax+0x0] ffffffffc00200d0: cmp rdx,0xfffffffffffffff5 ; -11 ffffffffc00200d7: je 0xfffffffffffffff5 ; -11 ffffffffc00200dd: jmp 0xffffffff81c00f10 ffffffffc00200e2: nop DWORD PTR [rax+rax*1+0x0] ffffffffc00200ea: nop WORD PTR [rax+rax*1+0x0] ffffffffc00200f0: cmp rdx,0xfffffffffffffff6 ; -10 ffffffffc00200f7: jg 0xffffffffc0020110 ffffffffc00200f9: cmp rdx,0xfffffffffffffff6 ; -10 ffffffffc0020100: je 0xfffffffffffffff6 ; -10 ffffffffc0020106: jmp 0xffffffff81c00f10 ffffffffc002010b: nop DWORD PTR [rax+rax*1+0x0] ffffffffc0020110: cmp rdx,0xfffffffffffffff7 ; -9 ffffffffc0020117: je 0xfffffffffffffff7 ; -9 ffffffffc002011d: jmp 0xffffffff81c00f10 ffffffffc0020122: nop DWORD PTR [rax+rax*1+0x0] ffffffffc002012a: nop WORD PTR [rax+rax*1+0x0] ffffffffc0020130: cmp rdx,0xfffffffffffffffb ; -5 ffffffffc0020137: jg 0xffffffffc00201d0 ffffffffc002013d: cmp rdx,0xfffffffffffffff9 ; -7 ffffffffc0020144: jg 0xffffffffc0020190 ffffffffc0020146: cmp rdx,0xfffffffffffffff8 ; -8 ffffffffc002014d: jg 0xffffffffc0020170 ffffffffc002014f: cmp rdx,0xfffffffffffffff8 ; -8 ffffffffc0020156: je 0xfffffffffffffff8 ; -8 ffffffffc002015c: jmp 0xffffffff81c00f10 ffffffffc0020161: nop DWORD PTR [rax+rax*1+0x0] ffffffffc0020169: nop DWORD PTR [rax+0x0] ffffffffc0020170: cmp rdx,0xfffffffffffffff9 ; -7 ffffffffc0020177: je 0xfffffffffffffff9 ; -7 ffffffffc002017d: jmp 0xffffffff81c00f10 ffffffffc0020182: nop DWORD PTR [rax+rax*1+0x0] ffffffffc002018a: nop WORD PTR [rax+rax*1+0x0] ffffffffc0020190: cmp rdx,0xfffffffffffffffa ; -6 ffffffffc0020197: jg 0xffffffffc00201b0 ffffffffc0020199: cmp rdx,0xfffffffffffffffa ; -6 ffffffffc00201a0: je 0xfffffffffffffffa ; -6 ffffffffc00201a6: jmp 0xffffffff81c00f10 ffffffffc00201ab: nop DWORD PTR [rax+rax*1+0x0] ffffffffc00201b0: cmp rdx,0xfffffffffffffffb ; -5 ffffffffc00201b7: je 0xfffffffffffffffb ; -5 ffffffffc00201bd: jmp 0xffffffff81c00f10 ffffffffc00201c2: nop DWORD PTR [rax+rax*1+0x0] ffffffffc00201ca: nop WORD PTR [rax+rax*1+0x0] ffffffffc00201d0: cmp rdx,0xfffffffffffffffd ; -3 ffffffffc00201d7: jg 0xffffffffc0020220 ffffffffc00201d9: cmp rdx,0xfffffffffffffffc ; -4 ffffffffc00201e0: jg 0xffffffffc0020200 ffffffffc00201e2: cmp rdx,0xfffffffffffffffc ; -4 ffffffffc00201e9: je 0xfffffffffffffffc ; -4 ffffffffc00201ef: jmp 0xffffffff81c00f10 ffffffffc00201f4: nop DWORD PTR [rax+rax*1+0x0] ffffffffc00201fc: nop DWORD PTR [rax+0x0] ffffffffc0020200: cmp rdx,0xfffffffffffffffd ; -3 ffffffffc0020207: je 0xfffffffffffffffd ; -3 ffffffffc002020d: jmp 0xffffffff81c00f10 ffffffffc0020212: nop DWORD PTR [rax+rax*1+0x0] ffffffffc002021a: nop WORD PTR [rax+rax*1+0x0] ffffffffc0020220: cmp rdx,0xfffffffffffffffe ; -2 ffffffffc0020227: jg 0xffffffffc0020240 ffffffffc0020229: cmp rdx,0xfffffffffffffffe ; -2 ffffffffc0020230: je 0xfffffffffffffffe ; -2 ffffffffc0020236: jmp 0xffffffff81c00f10 ffffffffc002023b: nop DWORD PTR [rax+rax*1+0x0] ffffffffc0020240: cmp rdx,0xffffffffffffffff ; -1 ffffffffc0020247: je 0xffffffffffffffff ; -1 ffffffffc002024d: jmp 0xffffffff81c00f10 The nops are there to align jump targets to 16 B. Performance =========== The tests were performed using the xdp_rxq_info sample program with the following command-line: 1. XDP_DRV: # xdp_rxq_info --dev eth0 --action XDP_DROP 2. XDP_SKB: # xdp_rxq_info --dev eth0 -S --action XDP_DROP 3. xdp-perf, from selftests/bpf: # test_progs -v -t xdp_perf Run with mitigations=auto ------------------------- Baseline: 1. 21.7 Mpps (21736190) 2. 3.8 Mpps (3837582) 3. 15 ns Dispatcher: 1. 30.2 Mpps (30176320) 2. 4.0 Mpps (4015579) 3. 5 ns Dispatcher (full; walk all entries, and fallback): 1. 22.0 Mpps (21986704) 2. 3.8 Mpps (3831298) 3. 17 ns Run with mitigations=off ------------------------ Baseline: 1. 29.9 Mpps (29875135) 2. 4.1 Mpps (4100179) 3. 4 ns Dispatcher: 1. 30.4 Mpps (30439241) 2. 4.1 Mpps (4109350) 1. 4 ns Dispatcher (full; walk all entries, and fallback): 1. 28.9 Mpps (28903269) 2. 4.1 Mpps (4080078) 3. 5 ns xdp-perf runs, aliged vs non-aligned jump targets ------------------------------------------------- In this test dispatchers of different sizes, with and without jump target alignment, were exercised. As outlined above the function lookup is performed via binary search. This means that depending on the pointer value of the function, it can reside in the upper or lower part of the search table. The performed tests were: 1. aligned, mititations=auto, function entry < other entries 2. aligned, mititations=auto, function entry > other entries 3. non-aligned, mititations=auto, function entry < other entries 4. non-aligned, mititations=auto, function entry > other entries 5. aligned, mititations=off, function entry < other entries 6. aligned, mititations=off, function entry > other entries 7. non-aligned, mititations=off, function entry < other entries 8. non-aligned, mititations=off, function entry > other entries The micro benchmarks showed that alignment of jump target has some positive impact. A reply to this cover letter will contain complete data for all runs. Multiple xdp-perf baseline with mitigations=auto ------------------------------------------------ Performance counter stats for './test_progs -v -t xdp_perf' (1024 runs): 16.69 msec task-clock # 0.984 CPUs utilized ( +- 0.08% ) 2 context-switches # 0.123 K/sec ( +- 1.11% ) 0 cpu-migrations # 0.000 K/sec ( +- 70.68% ) 97 page-faults # 0.006 M/sec ( +- 0.05% ) 49,254,635 cycles # 2.951 GHz ( +- 0.09% ) (12.28%) 42,138,558 instructions # 0.86 insn per cycle ( +- 0.02% ) (36.15%) 7,315,291 branches # 438.300 M/sec ( +- 0.01% ) (59.43%) 1,011,201 branch-misses # 13.82% of all branches ( +- 0.01% ) (83.31%) 15,440,788 L1-dcache-loads # 925.143 M/sec ( +- 0.00% ) (99.40%) 39,067 L1-dcache-load-misses # 0.25% of all L1-dcache hits ( +- 0.04% ) 6,531 LLC-loads # 0.391 M/sec ( +- 0.05% ) 442 LLC-load-misses # 6.76% of all LL-cache hits ( +- 0.77% ) <not supported> L1-icache-loads 57,964 L1-icache-load-misses ( +- 0.06% ) 15,442,496 dTLB-loads # 925.246 M/sec ( +- 0.00% ) 514 dTLB-load-misses # 0.00% of all dTLB cache hits ( +- 0.73% ) (40.57%) 130 iTLB-loads # 0.008 M/sec ( +- 2.75% ) (16.69%) <not counted> iTLB-load-misses ( +- 8.71% ) (0.60%) <not supported> L1-dcache-prefetches <not supported> L1-dcache-prefetch-misses 0.0169558 +- 0.0000127 seconds time elapsed ( +- 0.07% ) Multiple xdp-perf dispatcher with mitigations=auto -------------------------------------------------- Note that this includes generating the dispatcher. Performance counter stats for './test_progs -v -t xdp_perf' (1024 runs): 4.80 msec task-clock # 0.953 CPUs utilized ( +- 0.06% ) 1 context-switches # 0.258 K/sec ( +- 1.57% ) 0 cpu-migrations # 0.000 K/sec 97 page-faults # 0.020 M/sec ( +- 0.05% ) 14,185,861 cycles # 2.955 GHz ( +- 0.17% ) (50.49%) 45,691,935 instructions # 3.22 insn per cycle ( +- 0.01% ) (99.19%) 8,346,008 branches # 1738.709 M/sec ( +- 0.00% ) 13,046 branch-misses # 0.16% of all branches ( +- 0.10% ) 15,443,735 L1-dcache-loads # 3217.365 M/sec ( +- 0.00% ) 39,585 L1-dcache-load-misses # 0.26% of all L1-dcache hits ( +- 0.05% ) 7,138 LLC-loads # 1.487 M/sec ( +- 0.06% ) 671 LLC-load-misses # 9.40% of all LL-cache hits ( +- 0.73% ) <not supported> L1-icache-loads 56,213 L1-icache-load-misses ( +- 0.08% ) 15,443,735 dTLB-loads # 3217.365 M/sec ( +- 0.00% ) <not counted> dTLB-load-misses (0.00%) <not counted> iTLB-loads (0.00%) <not counted> iTLB-load-misses (0.00%) <not supported> L1-dcache-prefetches <not supported> L1-dcache-prefetch-misses 0.00503705 +- 0.00000546 seconds time elapsed ( +- 0.11% ) Revisions ========= v4->v5: [1] * Fixed s/xdp_ctx/ctx/ type-o (Toke) * Marked dispatcher trampoline with noinline attribute (Alexei) v3->v4: [2] * Moved away from doing dispatcher lookup based on the trampoline function, to a model where the dispatcher instance is explicitly passed to the bpf_dispatcher_change_prog() (Alexei) v2->v3: [3] * Removed xdp_call, and instead make the dispatcher available to all XDP users via bpf_prog_run_xdp() and dev_xdp_install(). (Toke) * Always enable the dispatcher, if available (Alexei) * Reuse BPF trampoline image allocator (Alexei) * Make sure the dispatcher is exercised in selftests (Alexei) * Only allow one dispatcher, and wire it to XDP v1->v2: [4] * Fixed i386 build warning (kbuild robot) * Made bpf_dispatcher_lookup() static (kbuild robot) * Make sure xdp_call.h is only enabled for builtins * Add xdp_call() to ixgbe, mlx4, and mlx5 RFC->v1: [5] * Improved error handling (Edward and Andrii) * Explicit cleanup (Andrii) * Use 32B with sext cmp (Alexei) * Align jump targets to 16B (Alexei) * 4 to 16 entries (Toke) * Added stats to xdp_call_run() [1] https://lore.kernel.org/bpf/20191211123017.13212-1-bjorn.topel@gmail.com/ [2] https://lore.kernel.org/bpf/20191209135522.16576-1-bjorn.topel@gmail.com/ [3] https://lore.kernel.org/bpf/20191123071226.6501-1-bjorn.topel@gmail.com/ [4] https://lore.kernel.org/bpf/20191119160757.27714-1-bjorn.topel@gmail.com/ [5] https://lore.kernel.org/bpf/20191113204737.31623-1-bjorn.topel@gmail.com/ ==================== Signed-off-by:
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Björn Töpel authored
>From Intel 64 and IA-32 Architectures Optimization Reference Manual, 3.4.1.4 Code Alignment, Assembly/Compiler Coding Rule 11: All branch targets should be 16-byte aligned. This commits aligns branch targets according to the Intel manual. The nops used to align branch targets make the dispatcher larger, and therefore the number of supported dispatch points/programs are descreased from 64 to 48. Signed-off-by:
Björn Töpel <bjorn.topel@intel.com> Signed-off-by:
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Björn Töpel authored
The xdp_perf is a dummy XDP test, only used to measure the the cost of jumping into a naive XDP program one million times. To build and run the program: $ cd tools/testing/selftests/bpf $ make $ ./test_progs -v -t xdp_perf Signed-off-by:
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Björn Töpel authored
In order to properly exercise the BPF dispatcher, this commit adds BPF dispatcher usage to BPF_TEST_RUN when executing XDP programs. Signed-off-by:
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Björn Töpel authored
This commit adds a BPF dispatcher for XDP. The dispatcher is updated from the XDP control-path, dev_xdp_install(), and used when an XDP program is run via bpf_prog_run_xdp(). Signed-off-by:
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Björn Töpel authored
The BPF dispatcher is a multi-way branch code generator, mainly targeted for XDP programs. When an XDP program is executed via the bpf_prog_run_xdp(), it is invoked via an indirect call. The indirect call has a substantial performance impact, when retpolines are enabled. The dispatcher transform indirect calls to direct calls, and therefore avoids the retpoline. The dispatcher is generated using the BPF JIT, and relies on text poking provided by bpf_arch_text_poke(). The dispatcher hijacks a trampoline function it via the __fentry__ nop of the trampoline. One dispatcher instance currently supports up to 64 dispatch points. A user creates a dispatcher with its corresponding trampoline with the DEFINE_BPF_DISPATCHER macro. Signed-off-by:
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Björn Töpel authored
Refactor the image allocation in the BPF trampoline code into a separate function, so it can be shared with the BPF dispatcher in upcoming commits. Signed-off-by:
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Andrii Nakryiko authored
Fix up perf_buffer.c selftest to take into account offline/missing CPUs. Fixes: ee5cf82c ("selftests/bpf: test perf buffer API") Signed-off-by:
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Andrii Nakryiko authored
It's quite common on some systems to have more CPUs enlisted as "possible", than there are (and could ever be) present/online CPUs. In such cases, perf_buffer creationg will fail due to inability to create perf event on missing CPU with error like this: libbpf: failed to open perf buffer event on cpu #16: No such device This patch fixes the logic of perf_buffer__new() to ignore CPUs that are missing or currently offline. In rare cases where user explicitly listed specific CPUs to connect to, behavior is unchanged: libbpf will try to open perf event buffer on specified CPU(s) anyways. Fixes: fb84b822 ("libbpf: add perf buffer API") Signed-off-by:
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Andrii Nakryiko authored
Add a bunch of test validating CPU mask parsing logic and error handling. Signed-off-by:
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Andrii Nakryiko authored
This logic is re-used for parsing a set of online CPUs. Having it as an isolated piece of code working with input string makes it conveninent to test this logic as well. While refactoring, also improve the robustness of original implementation. Signed-off-by:
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Alexei Starovoitov authored
Jakub Sitnicki says: ==================== This change has been suggested by Martin Lau [0] during a review of a related patch set that extends reuseport tests [1]. Patches 1 & 2 address a warning due to unrecognized section name from libbpf when running reuseport tests. We don't want to carry this warning into test_progs. Patches 3-8 massage the reuseport tests to ease the switch to test_progs framework. The intention here is to show the work. Happy to squash these, if needed. Patches 9-10 do the actual move and conversion to test_progs. Output from a test_progs run after changes pasted below. Thanks, Jakub [0] https://lore.kernel.org/bpf/20191123110751.6729-1-jakub@cloudflare.com/T/#m607d822caeb1eb5db101172821a78cc3896ff1c3 [1] https://lore.kernel.org/bpf/20191123110751.6729-1-jakub@cloudflare.com/T/#m55881bae9fb6e34837d07a0c0a7ffbc138f8d06f ==================== Acked-by:
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Jakub Sitnicki authored
The tests were originally written in abort-on-error style. With the switch to test_progs we can no longer do that. So at the risk of not cleaning up some resource on failure, we now return to the caller on error. That said, failure inside one test should not affect others because we run setup/cleanup before/after every test. Signed-off-by:
Jakub Sitnicki <jakub@cloudflare.com> Signed-off-by:
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Jakub Sitnicki authored
Do a pure move the show the actual work needed to adapt the tests in subsequent patch at the cost of breaking test_progs build for the moment. Signed-off-by:
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Jakub Sitnicki authored
Again, prepare for switching reuseport tests to test_progs framework. test_progs framework will print the subtest name for us if we set it. Signed-off-by:
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Jakub Sitnicki authored
Prepare for switching reuseport tests to test_progs framework, where we don't have the luxury to terminate the process on failure. Modify setup helpers to signal failure via the return value with the help of a macro similar to the one currently in use by the tests. Signed-off-by:
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Jakub Sitnicki authored
Prepare for switching reuseport tests to test_progs framework. Loop over the tests and perform setup/cleanup for each test separately, remembering that with test_progs we can select tests to run. Signed-off-by:
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Jakub Sitnicki authored
Prepare for iterating over individual tests without introducing another nested loop in the main test function. Signed-off-by:
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Jakub Sitnicki authored
Having string arrays to map socket family & type to a name prevents us from unrolling the test runner loop in the subsequent patch. Introduce helpers that do the same thing. Signed-off-by:
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Jakub Sitnicki authored
Update the only function that is not using sa_family_t in this source file. Signed-off-by:
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Jakub Sitnicki authored
Now that libbpf can recognize SK_REUSEPORT programs, we no longer have to pass a prog_type hint before loading the object file. Signed-off-by:
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Jakub Sitnicki authored
Allow loading BPF object files that contain SK_REUSEPORT programs without having to manually set the program type before load if the the section name is set to "sk_reuseport". Makes user-space code needed to load SK_REUSEPORT BPF program more concise. Signed-off-by:
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- 12 Dec, 2019 2 commits
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Andrii Nakryiko authored
On ppc64le __u64 and __s64 are defined as long int and unsigned long int, respectively. This causes compiler to emit warning when %lld/%llu are used to printf 64-bit numbers. Fix this by casting to size_t/ssize_t with %zu and %zd format specifiers, respectively. v1->v2: - use size_t/ssize_t instead of custom typedefs (Martin). Fixes: 1f8e2bcb ("libbpf: Refactor relocation handling") Fixes: abd29c93 ("libbpf: allow specifying map definitions using BTF") Signed-off-by:
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Daniel Borkmann authored
After Spectre 2 fix via 290af866 ("bpf: introduce BPF_JIT_ALWAYS_ON config") most major distros use BPF_JIT_ALWAYS_ON configuration these days which compiles out the BPF interpreter entirely and always enables the JIT. Also given recent fix in e1608f3f ("bpf: Avoid setting bpf insns pages read-only when prog is jited"), we additionally avoid fragmenting the direct map for the BPF insns pages sitting in the general data heap since they are not used during execution. Latter is only needed when run through the interpreter. Since both x86 and arm64 JITs have seen a lot of exposure over the years, are generally most up to date and maintained, there is more downside in !BPF_JIT_ALWAYS_ON configurations to have the interpreter enabled by default rather than the JIT. Add a ARCH_WANT_DEFAULT_BPF_JIT config which archs can use to set the bpf_jit_{enable,kallsyms} to 1. Back in the days the bpf_jit_kallsyms knob was set to 0 by default since major distros still had /proc/kallsyms addresses exposed to unprivileged user space which is not the case anymore. Hence both knobs are set via BPF_JIT_DEFAULT_ON which is set to 'y' in case of BPF_JIT_ALWAYS_ON or ARCH_WANT_DEFAULT_BPF_JIT. Signed-off-by:
Daniel Borkmann <daniel@iogearbox.net> Signed-off-by:
Will Deacon <will@kernel.org> Acked-by:
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- 11 Dec, 2019 3 commits
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Daniel Borkmann authored
Allow for audit messages to be emitted upon BPF program load and unload for having a timeline of events. The load itself is in syscall context, so additional info about the process initiating the BPF prog creation can be logged and later directly correlated to the unload event. The only info really needed from BPF side is the globally unique prog ID where then audit user space tooling can query / dump all info needed about the specific BPF program right upon load event and enrich the record, thus these changes needed here can be kept small and non-intrusive to the core. Raw example output: # auditctl -D # auditctl -a always,exit -F arch=x86_64 -S bpf # ausearch --start recent -m 1334 ... ---- time->Wed Nov 27 16:04:13 2019 type=PROCTITLE msg=audit(1574867053.120:84664): proctitle="./bpf" type=SYSCALL msg=audit(1574867053.120:84664): arch=c000003e syscall=321 \ success=yes exit=3 a0=5 a1=7ffea484fbe0 a2=70 a3=0 items=0 ppid=7477 \ pid=12698 auid=1001 uid=1001 gid=1001 euid=1001 suid=1001 fsuid=1001 \ egid=1001 sgid=1001 fsgid=1001 tty=pts2 ses=4 comm="bpf" \ exe="/home/jolsa/auditd/audit-testsuite/tests/bpf/bpf" \ subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 key=(null) type=UNKNOWN[1334] msg=audit(1574867053.120:84664): prog-id=76 op=LOAD ---- time->Wed Nov 27 16:04:13 2019 type=UNKNOWN[1334] msg=audit(1574867053.120:84665): prog-id=76 op=UNLOAD ... Signed-off-by:Jiri Olsa <jolsa@kernel.org> Signed-off-by:
Paul Moore <paul@paul-moore.com> Link: https://lore.kernel.org/bpf/20191206214934.11319-1-jolsa@kernel.org
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Stanislav Fomichev authored
Switch existing pattern of "offsetof(..., member) + FIELD_SIZEOF(..., member)' to "offsetofend(..., member)" which does exactly what we need without all the copy-paste. Suggested-by:
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Andrii Nakryiko authored
New development cycles starts, bump to v0.0.7 proactively. Signed-off-by:
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