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author | Linus Torvalds <torvalds@linux-foundation.org> | 2016-07-25 13:20:41 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-07-25 13:20:41 -0700 |
commit | 7e4dc77b2869a683fc43c0394fca5441816390ba (patch) | |
tree | 62e734c599bc1da2712fdb63be996622c415a83a /tools/lib/bpf/libbpf.c | |
parent | 89e7eb098adfe342bc036f00201eb579d448f033 (diff) | |
parent | 5048c2af078d5976895d521262a8802ea791f3b0 (diff) | |
download | lwn-7e4dc77b2869a683fc43c0394fca5441816390ba.tar.gz lwn-7e4dc77b2869a683fc43c0394fca5441816390ba.zip |
Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates from Ingo Molnar:
"With over 300 commits it's been a busy cycle - with most of the work
concentrated on the tooling side (as it should).
The main kernel side enhancements were:
- Add per event callchain limit: Recently we introduced a sysctl to
tune the max-stack for all events for which callchains were
requested:
$ sysctl kernel.perf_event_max_stack
kernel.perf_event_max_stack = 127
Now this patch introduces a way to configure this per event, i.e.
this becomes possible:
$ perf record -e sched:*/max-stack=2/ -e block:*/max-stack=10/ -a
allowing finer tuning of how much buffer space callchains use.
This uses an u16 from the reserved space at the end, leaving
another u16 for future use.
There has been interest in even finer tuning, namely to control the
max stack for kernel and userspace callchains separately. Further
discussion is needed, we may for instance use the remaining u16 for
that and when it is present, assume that the sample_max_stack
introduced in this patch applies for the kernel, and the u16 left
is used for limiting the userspace callchain (Arnaldo Carvalho de
Melo)
- Optimize AUX event (hardware assisted side-band event) delivery
(Kan Liang)
- Rework Intel family name macro usage (this is partially x86 arch
work) (Dave Hansen)
- Refine and fix Intel LBR support (David Carrillo-Cisneros)
- Add support for Intel 'TopDown' events (Andi Kleen)
- Intel uncore PMU driver fixes and enhancements (Kan Liang)
- ... other misc changes.
Here's an incomplete list of the tooling enhancements (but there's
much more, see the shortlog and the git log for details):
- Support cross unwinding, i.e. collecting '--call-graph dwarf'
perf.data files in one machine and then doing analysis in another
machine of a different hardware architecture. This enables, for
instance, to do:
$ perf record -a --call-graph dwarf
on a x86-32 or aarch64 system and then do 'perf report' on it on a
x86_64 workstation (He Kuang)
- Allow reading from a backward ring buffer (one setup via
sys_perf_event_open() with perf_event_attr.write_backward = 1)
(Wang Nan)
- Finish merging initial SDT (Statically Defined Traces) support, see
cset comments for details about how it all works (Masami Hiramatsu)
- Support attaching eBPF programs to tracepoints (Wang Nan)
- Add demangling of symbols in programs written in the Rust language
(David Tolnay)
- Add support for tracepoints in the python binding, including an
example, that sets up and parses sched:sched_switch events,
tools/perf/python/tracepoint.py (Jiri Olsa)
- Introduce --stdio-color to set up the color output mode selection
in 'annotate' and 'report', allowing emit color escape sequences
when redirecting the output of these tools (Arnaldo Carvalho de
Melo)
- Add 'callindent' option to 'perf script -F', to indent the Intel PT
call stack, making this output more ftrace-like (Adrian Hunter,
Andi Kleen)
- Allow dumping the object files generated by llvm when processing
eBPF scriptlet events (Wang Nan)
- Add stackcollapse.py script to help generating flame graphs (Paolo
Bonzini)
- Add --ldlat option to 'perf mem' to specify load latency for loads
event (e.g. cpu/mem-loads/ ) (Jiri Olsa)
- Tooling support for Intel TopDown counters, recently added to the
kernel (Andi Kleen)"
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (303 commits)
perf tests: Add is_printable_array test
perf tools: Make is_printable_array global
perf script python: Fix string vs byte array resolving
perf probe: Warn unmatched function filter correctly
perf cpu_map: Add more helpers
perf stat: Balance opening and reading events
tools: Copy linux/{hash,poison}.h and check for drift
perf tools: Remove include/linux/list.h from perf's MANIFEST
tools: Copy the bitops files accessed from the kernel and check for drift
Remove: kernel unistd*h files from perf's MANIFEST, not used
perf tools: Remove tools/perf/util/include/linux/const.h
perf tools: Remove tools/perf/util/include/asm/byteorder.h
perf tools: Add missing linux/compiler.h include to perf-sys.h
perf jit: Remove some no-op error handling
perf jit: Add missing curly braces
objtool: Initialize variable to silence old compiler
objtool: Add -I$(srctree)/tools/arch/$(ARCH)/include/uapi
perf record: Add --tail-synthesize option
perf session: Don't warn about out of order event if write_backward is used
perf tools: Enable overwrite settings
...
Diffstat (limited to 'tools/lib/bpf/libbpf.c')
-rw-r--r-- | tools/lib/bpf/libbpf.c | 149 |
1 files changed, 96 insertions, 53 deletions
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 7e543c3102d4..32e6b6bc6f7d 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -4,6 +4,19 @@ * Copyright (C) 2013-2015 Alexei Starovoitov <ast@kernel.org> * Copyright (C) 2015 Wang Nan <wangnan0@huawei.com> * Copyright (C) 2015 Huawei Inc. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; + * version 2.1 of the License (not later!) + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this program; if not, see <http://www.gnu.org/licenses> */ #include <stdlib.h> @@ -71,12 +84,13 @@ static const char *libbpf_strerror_table[NR_ERRNO] = { [ERRCODE_OFFSET(LIBELF)] = "Something wrong in libelf", [ERRCODE_OFFSET(FORMAT)] = "BPF object format invalid", [ERRCODE_OFFSET(KVERSION)] = "'version' section incorrect or lost", - [ERRCODE_OFFSET(ENDIAN)] = "Endian missmatch", + [ERRCODE_OFFSET(ENDIAN)] = "Endian mismatch", [ERRCODE_OFFSET(INTERNAL)] = "Internal error in libbpf", [ERRCODE_OFFSET(RELOC)] = "Relocation failed", [ERRCODE_OFFSET(VERIFY)] = "Kernel verifier blocks program loading", [ERRCODE_OFFSET(PROG2BIG)] = "Program too big", [ERRCODE_OFFSET(KVER)] = "Incorrect kernel version", + [ERRCODE_OFFSET(PROGTYPE)] = "Kernel doesn't support this program type", }; int libbpf_strerror(int err, char *buf, size_t size) @@ -145,6 +159,7 @@ struct bpf_program { char *section_name; struct bpf_insn *insns; size_t insns_cnt; + enum bpf_prog_type type; struct { int insn_idx; @@ -286,6 +301,7 @@ bpf_program__init(void *data, size_t size, char *name, int idx, prog->idx = idx; prog->instances.fds = NULL; prog->instances.nr = -1; + prog->type = BPF_PROG_TYPE_KPROBE; return 0; errout: @@ -881,8 +897,8 @@ static int bpf_object__collect_reloc(struct bpf_object *obj) } static int -load_program(struct bpf_insn *insns, int insns_cnt, - char *license, u32 kern_version, int *pfd) +load_program(enum bpf_prog_type type, struct bpf_insn *insns, + int insns_cnt, char *license, u32 kern_version, int *pfd) { int ret; char *log_buf; @@ -894,9 +910,8 @@ load_program(struct bpf_insn *insns, int insns_cnt, if (!log_buf) pr_warning("Alloc log buffer for bpf loader error, continue without log\n"); - ret = bpf_load_program(BPF_PROG_TYPE_KPROBE, insns, - insns_cnt, license, kern_version, - log_buf, BPF_LOG_BUF_SIZE); + ret = bpf_load_program(type, insns, insns_cnt, license, + kern_version, log_buf, BPF_LOG_BUF_SIZE); if (ret >= 0) { *pfd = ret; @@ -912,15 +927,27 @@ load_program(struct bpf_insn *insns, int insns_cnt, pr_warning("-- BEGIN DUMP LOG ---\n"); pr_warning("\n%s\n", log_buf); pr_warning("-- END LOG --\n"); + } else if (insns_cnt >= BPF_MAXINSNS) { + pr_warning("Program too large (%d insns), at most %d insns\n", + insns_cnt, BPF_MAXINSNS); + ret = -LIBBPF_ERRNO__PROG2BIG; } else { - if (insns_cnt >= BPF_MAXINSNS) { - pr_warning("Program too large (%d insns), at most %d insns\n", - insns_cnt, BPF_MAXINSNS); - ret = -LIBBPF_ERRNO__PROG2BIG; - } else if (log_buf) { - pr_warning("log buffer is empty\n"); - ret = -LIBBPF_ERRNO__KVER; + /* Wrong program type? */ + if (type != BPF_PROG_TYPE_KPROBE) { + int fd; + + fd = bpf_load_program(BPF_PROG_TYPE_KPROBE, insns, + insns_cnt, license, kern_version, + NULL, 0); + if (fd >= 0) { + close(fd); + ret = -LIBBPF_ERRNO__PROGTYPE; + goto out; + } } + + if (log_buf) + ret = -LIBBPF_ERRNO__KVER; } out: @@ -955,7 +982,7 @@ bpf_program__load(struct bpf_program *prog, pr_warning("Program '%s' is inconsistent: nr(%d) != 1\n", prog->section_name, prog->instances.nr); } - err = load_program(prog->insns, prog->insns_cnt, + err = load_program(prog->type, prog->insns, prog->insns_cnt, license, kern_version, &fd); if (!err) prog->instances.fds[0] = fd; @@ -984,7 +1011,7 @@ bpf_program__load(struct bpf_program *prog, continue; } - err = load_program(result.new_insn_ptr, + err = load_program(prog->type, result.new_insn_ptr, result.new_insn_cnt, license, kern_version, &fd); @@ -1186,20 +1213,14 @@ bpf_object__next(struct bpf_object *prev) return next; } -const char * -bpf_object__get_name(struct bpf_object *obj) +const char *bpf_object__name(struct bpf_object *obj) { - if (!obj) - return ERR_PTR(-EINVAL); - return obj->path; + return obj ? obj->path : ERR_PTR(-EINVAL); } -unsigned int -bpf_object__get_kversion(struct bpf_object *obj) +unsigned int bpf_object__kversion(struct bpf_object *obj) { - if (!obj) - return 0; - return obj->kern_version; + return obj ? obj->kern_version : 0; } struct bpf_program * @@ -1224,9 +1245,8 @@ bpf_program__next(struct bpf_program *prev, struct bpf_object *obj) return &obj->programs[idx]; } -int bpf_program__set_private(struct bpf_program *prog, - void *priv, - bpf_program_clear_priv_t clear_priv) +int bpf_program__set_priv(struct bpf_program *prog, void *priv, + bpf_program_clear_priv_t clear_priv) { if (prog->priv && prog->clear_priv) prog->clear_priv(prog, prog->priv); @@ -1236,10 +1256,9 @@ int bpf_program__set_private(struct bpf_program *prog, return 0; } -int bpf_program__get_private(struct bpf_program *prog, void **ppriv) +void *bpf_program__priv(struct bpf_program *prog) { - *ppriv = prog->priv; - return 0; + return prog ? prog->priv : ERR_PTR(-EINVAL); } const char *bpf_program__title(struct bpf_program *prog, bool needs_copy) @@ -1311,32 +1330,61 @@ int bpf_program__nth_fd(struct bpf_program *prog, int n) return fd; } -int bpf_map__get_fd(struct bpf_map *map) +static void bpf_program__set_type(struct bpf_program *prog, + enum bpf_prog_type type) { - if (!map) - return -EINVAL; - - return map->fd; + prog->type = type; } -int bpf_map__get_def(struct bpf_map *map, struct bpf_map_def *pdef) +int bpf_program__set_tracepoint(struct bpf_program *prog) { - if (!map || !pdef) + if (!prog) return -EINVAL; + bpf_program__set_type(prog, BPF_PROG_TYPE_TRACEPOINT); + return 0; +} - *pdef = map->def; +int bpf_program__set_kprobe(struct bpf_program *prog) +{ + if (!prog) + return -EINVAL; + bpf_program__set_type(prog, BPF_PROG_TYPE_KPROBE); return 0; } -const char *bpf_map__get_name(struct bpf_map *map) +static bool bpf_program__is_type(struct bpf_program *prog, + enum bpf_prog_type type) { - if (!map) - return NULL; - return map->name; + return prog ? (prog->type == type) : false; +} + +bool bpf_program__is_tracepoint(struct bpf_program *prog) +{ + return bpf_program__is_type(prog, BPF_PROG_TYPE_TRACEPOINT); +} + +bool bpf_program__is_kprobe(struct bpf_program *prog) +{ + return bpf_program__is_type(prog, BPF_PROG_TYPE_KPROBE); +} + +int bpf_map__fd(struct bpf_map *map) +{ + return map ? map->fd : -EINVAL; } -int bpf_map__set_private(struct bpf_map *map, void *priv, - bpf_map_clear_priv_t clear_priv) +const struct bpf_map_def *bpf_map__def(struct bpf_map *map) +{ + return map ? &map->def : ERR_PTR(-EINVAL); +} + +const char *bpf_map__name(struct bpf_map *map) +{ + return map ? map->name : NULL; +} + +int bpf_map__set_priv(struct bpf_map *map, void *priv, + bpf_map_clear_priv_t clear_priv) { if (!map) return -EINVAL; @@ -1351,14 +1399,9 @@ int bpf_map__set_private(struct bpf_map *map, void *priv, return 0; } -int bpf_map__get_private(struct bpf_map *map, void **ppriv) +void *bpf_map__priv(struct bpf_map *map) { - if (!map) - return -EINVAL; - - if (ppriv) - *ppriv = map->priv; - return 0; + return map ? map->priv : ERR_PTR(-EINVAL); } struct bpf_map * @@ -1389,7 +1432,7 @@ bpf_map__next(struct bpf_map *prev, struct bpf_object *obj) } struct bpf_map * -bpf_object__get_map_by_name(struct bpf_object *obj, const char *name) +bpf_object__find_map_by_name(struct bpf_object *obj, const char *name) { struct bpf_map *pos; |