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	perf tools: Synthesize PERF_RECORD_* for loaded BPF programs
This patch synthesize PERF_RECORD_KSYMBOL and PERF_RECORD_BPF_EVENT for
BPF programs loaded before perf-record. This is achieved by gathering
information about all BPF programs via sys_bpf.
Committer notes:
Fix the build on some older systems such as amazonlinux:1 where it was
breaking with:
  util/bpf-event.c: In function 'perf_event__synthesize_one_bpf_prog':
  util/bpf-event.c:52:9: error: missing initializer for field 'type' of 'struct bpf_prog_info' [-Werror=missing-field-initializers]
    struct bpf_prog_info info = {};
           ^
  In file included from /git/linux/tools/lib/bpf/bpf.h:26:0,
                   from util/bpf-event.c:3:
  /git/linux/tools/include/uapi/linux/bpf.h:2699:8: note: 'type' declared here
    __u32 type;
          ^
  cc1: all warnings being treated as errors
Further fix on a centos:6 system:
  cc1: warnings being treated as errors
  util/bpf-event.c: In function 'perf_event__synthesize_one_bpf_prog':
  util/bpf-event.c:50: error: 'func_info_rec_size' may be used uninitialized in this function
The compiler is wrong, but to silence it, initialize that variable to
zero.
One more fix, this time for debian:experimental-x-mips, x-mips64 and
x-mipsel:
  util/bpf-event.c: In function 'perf_event__synthesize_one_bpf_prog':
  util/bpf-event.c:93:16: error: implicit declaration of function 'calloc' [-Werror=implicit-function-declaration]
     func_infos = calloc(sub_prog_cnt, func_info_rec_size);
                  ^~~~~~
  util/bpf-event.c:93:16: error: incompatible implicit declaration of built-in function 'calloc' [-Werror]
  util/bpf-event.c:93:16: note: include '<stdlib.h>' or provide a declaration of 'calloc'
Add the missing header.
Committer testing:
  # perf record --bpf-event sleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.021 MB perf.data (7 samples) ]
  # perf report -D | grep PERF_RECORD_BPF_EVENT | nl
     1	0 0x4b10 [0x18]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 13
     2	0 0x4c60 [0x18]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 14
     3	0 0x4db0 [0x18]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 15
     4	0 0x4f00 [0x18]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 16
     5	0 0x5050 [0x18]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 17
     6	0 0x51a0 [0x18]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 18
     7	0 0x52f0 [0x18]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 21
     8	0 0x5440 [0x18]: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 22
  # bpftool prog
  13: cgroup_skb  tag 7be49e3934a125ba  gpl
	loaded_at 2019-01-19T09:09:43-0300  uid 0
	xlated 296B  jited 229B  memlock 4096B  map_ids 13,14
  14: cgroup_skb  tag 2a142ef67aaad174  gpl
	loaded_at 2019-01-19T09:09:43-0300  uid 0
	xlated 296B  jited 229B  memlock 4096B  map_ids 13,14
  15: cgroup_skb  tag 7be49e3934a125ba  gpl
	loaded_at 2019-01-19T09:09:43-0300  uid 0
	xlated 296B  jited 229B  memlock 4096B  map_ids 15,16
  16: cgroup_skb  tag 2a142ef67aaad174  gpl
	loaded_at 2019-01-19T09:09:43-0300  uid 0
	xlated 296B  jited 229B  memlock 4096B  map_ids 15,16
  17: cgroup_skb  tag 7be49e3934a125ba  gpl
	loaded_at 2019-01-19T09:09:44-0300  uid 0
	xlated 296B  jited 229B  memlock 4096B  map_ids 17,18
  18: cgroup_skb  tag 2a142ef67aaad174  gpl
	loaded_at 2019-01-19T09:09:44-0300  uid 0
	xlated 296B  jited 229B  memlock 4096B  map_ids 17,18
  21: cgroup_skb  tag 7be49e3934a125ba  gpl
	loaded_at 2019-01-19T09:09:45-0300  uid 0
	xlated 296B  jited 229B  memlock 4096B  map_ids 21,22
  22: cgroup_skb  tag 2a142ef67aaad174  gpl
	loaded_at 2019-01-19T09:09:45-0300  uid 0
	xlated 296B  jited 229B  memlock 4096B  map_ids 21,22
  #
  # perf report -D | grep -B22 PERF_RECORD_KSYMBOL
  . ... raw event: size 312 bytes
  .  0000:  11 00 00 00 00 00 38 01 ff 44 06 c0 ff ff ff ff  ......8..D......
  .  0010:  e5 00 00 00 01 00 00 00 62 70 66 5f 70 72 6f 67  ........bpf_prog
  .  0020:  5f 37 62 65 34 39 65 33 39 33 34 61 31 32 35 62  _7be49e3934a125b
  .  0030:  61 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  a...............
   <SNIP zeroes>
  .  0110:  00 00 00 00 00 00 00 00 21 00 00 00 00 00 00 00  ........!.......
  .  0120:  7b e4 9e 39 34 a1 25 ba 00 00 00 00 00 00 00 00  {..94.%.........
  .  0130:  00 00 00 00 00 00 00 00                          ........
  0 0x49d8 [0x138]: PERF_RECORD_KSYMBOL ksymbol event with addr ffffffffc00644ff len 229 type 1 flags 0x0 name bpf_prog_7be49e3934a125ba
  --
  . ... raw event: size 312 bytes
  .  0000:  11 00 00 00 00 00 38 01 48 6d 06 c0 ff ff ff ff  ......8.Hm......
  .  0010:  e5 00 00 00 01 00 00 00 62 70 66 5f 70 72 6f 67  ........bpf_prog
  .  0020:  5f 32 61 31 34 32 65 66 36 37 61 61 61 64 31 37  _2a142ef67aaad17
  .  0030:  34 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  4...............
   <SNIP zeroes>
  .  0110:  00 00 00 00 00 00 00 00 21 00 00 00 00 00 00 00  ........!.......
  .  0120:  2a 14 2e f6 7a aa d1 74 00 00 00 00 00 00 00 00  *...z..t........
  .  0130:  00 00 00 00 00 00 00 00                          ........
  0 0x4b28 [0x138]: PERF_RECORD_KSYMBOL ksymbol event with addr ffffffffc0066d48 len 229 type 1 flags 0x0 name bpf_prog_2a142ef67aaad174
  --
  . ... raw event: size 312 bytes
  .  0000:  11 00 00 00 00 00 38 01 04 cf 03 c0 ff ff ff ff  ......8.........
  .  0010:  e5 00 00 00 01 00 00 00 62 70 66 5f 70 72 6f 67  ........bpf_prog
  .  0020:  5f 37 62 65 34 39 65 33 39 33 34 61 31 32 35 62  _7be49e3934a125b
  .  0030:  61 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  a...............
   <SNIP zeroes>
  .  0110:  00 00 00 00 00 00 00 00 21 00 00 00 00 00 00 00  ........!.......
  .  0120:  7b e4 9e 39 34 a1 25 ba 00 00 00 00 00 00 00 00  {..94.%.........
  .  0130:  00 00 00 00 00 00 00 00                          ........
  0 0x4c78 [0x138]: PERF_RECORD_KSYMBOL ksymbol event with addr ffffffffc003cf04 len 229 type 1 flags 0x0 name bpf_prog_7be49e3934a125ba
  --
  . ... raw event: size 312 bytes
  .  0000:  11 00 00 00 00 00 38 01 96 28 04 c0 ff ff ff ff  ......8..(......
  .  0010:  e5 00 00 00 01 00 00 00 62 70 66 5f 70 72 6f 67  ........bpf_prog
  .  0020:  5f 32 61 31 34 32 65 66 36 37 61 61 61 64 31 37  _2a142ef67aaad17
  .  0030:  34 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  4...............
   <SNIP zeroes>
  .  0110:  00 00 00 00 00 00 00 00 21 00 00 00 00 00 00 00  ........!.......
  .  0120:  2a 14 2e f6 7a aa d1 74 00 00 00 00 00 00 00 00  *...z..t........
  .  0130:  00 00 00 00 00 00 00 00                          ........
  0 0x4dc8 [0x138]: PERF_RECORD_KSYMBOL ksymbol event with addr ffffffffc0042896 len 229 type 1 flags 0x0 name bpf_prog_2a142ef67aaad174
  --
  . ... raw event: size 312 bytes
  .  0000:  11 00 00 00 00 00 38 01 05 13 17 c0 ff ff ff ff  ......8.........
  .  0010:  e5 00 00 00 01 00 00 00 62 70 66 5f 70 72 6f 67  ........bpf_prog
  .  0020:  5f 37 62 65 34 39 65 33 39 33 34 61 31 32 35 62  _7be49e3934a125b
  .  0030:  61 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  a...............
   <SNIP zeroes>
  .  0110:  00 00 00 00 00 00 00 00 21 00 00 00 00 00 00 00  ........!.......
  .  0120:  7b e4 9e 39 34 a1 25 ba 00 00 00 00 00 00 00 00  {..94.%.........
  .  0130:  00 00 00 00 00 00 00 00                          ........
  0 0x4f18 [0x138]: PERF_RECORD_KSYMBOL ksymbol event with addr ffffffffc0171305 len 229 type 1 flags 0x0 name bpf_prog_7be49e3934a125ba
  --
  . ... raw event: size 312 bytes
  .  0000:  11 00 00 00 00 00 38 01 0a 8c 23 c0 ff ff ff ff  ......8...#.....
  .  0010:  e5 00 00 00 01 00 00 00 62 70 66 5f 70 72 6f 67  ........bpf_prog
  .  0020:  5f 32 61 31 34 32 65 66 36 37 61 61 61 64 31 37  _2a142ef67aaad17
  .  0030:  34 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  4...............
   <SNIP zeroes>
  .  0110:  00 00 00 00 00 00 00 00 21 00 00 00 00 00 00 00  ........!.......
  .  0120:  2a 14 2e f6 7a aa d1 74 00 00 00 00 00 00 00 00  *...z..t........
  .  0130:  00 00 00 00 00 00 00 00                          ........
  0 0x5068 [0x138]: PERF_RECORD_KSYMBOL ksymbol event with addr ffffffffc0238c0a len 229 type 1 flags 0x0 name bpf_prog_2a142ef67aaad174
  --
  . ... raw event: size 312 bytes
  .  0000:  11 00 00 00 00 00 38 01 2a a5 a4 c0 ff ff ff ff  ......8.*.......
  .  0010:  e5 00 00 00 01 00 00 00 62 70 66 5f 70 72 6f 67  ........bpf_prog
  .  0020:  5f 37 62 65 34 39 65 33 39 33 34 61 31 32 35 62  _7be49e3934a125b
  .  0030:  61 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  a...............
   <SNIP zeroes>
  .  0110:  00 00 00 00 00 00 00 00 21 00 00 00 00 00 00 00  ........!.......
  .  0120:  7b e4 9e 39 34 a1 25 ba 00 00 00 00 00 00 00 00  {..94.%.........
  .  0130:  00 00 00 00 00 00 00 00                          ........
  0 0x51b8 [0x138]: PERF_RECORD_KSYMBOL ksymbol event with addr ffffffffc0a4a52a len 229 type 1 flags 0x0 name bpf_prog_7be49e3934a125ba
  --
  . ... raw event: size 312 bytes
  .  0000:  11 00 00 00 00 00 38 01 9b c9 a4 c0 ff ff ff ff  ......8.........
  .  0010:  e5 00 00 00 01 00 00 00 62 70 66 5f 70 72 6f 67  ........bpf_prog
  .  0020:  5f 32 61 31 34 32 65 66 36 37 61 61 61 64 31 37  _2a142ef67aaad17
  .  0030:  34 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  4...............
   <SNIP zeroes>
  .  0110:  00 00 00 00 00 00 00 00 21 00 00 00 00 00 00 00  ........!.......
  .  0120:  2a 14 2e f6 7a aa d1 74 00 00 00 00 00 00 00 00  *...z..t........
  .  0130:  00 00 00 00 00 00 00 00                          ........
  0 0x5308 [0x138]: PERF_RECORD_KSYMBOL ksymbol event with addr ffffffffc0a4c99b len 229 type 1 flags 0x0 name bpf_prog_2a142ef67aaad174
Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: kernel-team@fb.com
Cc: netdev@vger.kernel.org
Link: http://lkml.kernel.org/r/20190117161521.1341602-8-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
			
			
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					 3 changed files with 264 additions and 0 deletions
				
			
		| 
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			@ -41,6 +41,7 @@
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#include "util/perf-hooks.h"
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#include "util/time-utils.h"
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#include "util/units.h"
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#include "util/bpf-event.h"
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#include "asm/bug.h"
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#include <errno.h>
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			@ -1082,6 +1083,11 @@ static int record__synthesize(struct record *rec, bool tail)
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		return err;
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	}
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	err = perf_event__synthesize_bpf_events(tool, process_synthesized_event,
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						machine, opts);
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	if (err < 0)
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		pr_warning("Couldn't synthesize bpf events.\n");
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	err = __machine__synthesize_threads(machine, tool, &opts->target, rec->evlist->threads,
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					    process_synthesized_event, opts->sample_address,
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					    1);
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						 | 
				
			
			
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			@ -1,10 +1,25 @@
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// SPDX-License-Identifier: GPL-2.0
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#include <errno.h>
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#include <stdlib.h>
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#include <bpf/bpf.h>
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#include <bpf/btf.h>
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#include <linux/btf.h>
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#include "bpf-event.h"
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#include "debug.h"
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#include "symbol.h"
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#define ptr_to_u64(ptr)    ((__u64)(unsigned long)(ptr))
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static int snprintf_hex(char *buf, size_t size, unsigned char *data, size_t len)
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{
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	int ret = 0;
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	size_t i;
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	for (i = 0; i < len; i++)
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		ret += snprintf(buf + ret, size - ret, "%02x", data[i]);
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	return ret;
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}
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int machine__process_bpf_event(struct machine *machine __maybe_unused,
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			       union perf_event *event,
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			       struct perf_sample *sample __maybe_unused)
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			@ -13,3 +28,230 @@ int machine__process_bpf_event(struct machine *machine __maybe_unused,
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		perf_event__fprintf_bpf_event(event, stdout);
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	return 0;
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}
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/*
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 * Synthesize PERF_RECORD_KSYMBOL and PERF_RECORD_BPF_EVENT for one bpf
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 * program. One PERF_RECORD_BPF_EVENT is generated for the program. And
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 * one PERF_RECORD_KSYMBOL is generated for each sub program.
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 *
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 * Returns:
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 *    0 for success;
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 *   -1 for failures;
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 *   -2 for lack of kernel support.
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 */
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static int perf_event__synthesize_one_bpf_prog(struct perf_tool *tool,
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					       perf_event__handler_t process,
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					       struct machine *machine,
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					       int fd,
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					       union perf_event *event,
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					       struct record_opts *opts)
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{
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	struct ksymbol_event *ksymbol_event = &event->ksymbol_event;
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	struct bpf_event *bpf_event = &event->bpf_event;
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	u32 sub_prog_cnt, i, func_info_rec_size = 0;
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	u8 (*prog_tags)[BPF_TAG_SIZE] = NULL;
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	struct bpf_prog_info info = { .type = 0, };
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	u32 info_len = sizeof(info);
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	void *func_infos = NULL;
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	u64 *prog_addrs = NULL;
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	struct btf *btf = NULL;
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	u32 *prog_lens = NULL;
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	bool has_btf = false;
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	char errbuf[512];
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	int err = 0;
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	/* Call bpf_obj_get_info_by_fd() to get sizes of arrays */
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	err = bpf_obj_get_info_by_fd(fd, &info, &info_len);
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	if (err) {
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		pr_debug("%s: failed to get BPF program info: %s, aborting\n",
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			 __func__, str_error_r(errno, errbuf, sizeof(errbuf)));
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		return -1;
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	}
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	if (info_len < offsetof(struct bpf_prog_info, prog_tags)) {
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		pr_debug("%s: the kernel is too old, aborting\n", __func__);
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		return -2;
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	}
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	/* number of ksyms, func_lengths, and tags should match */
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	sub_prog_cnt = info.nr_jited_ksyms;
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	if (sub_prog_cnt != info.nr_prog_tags ||
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	    sub_prog_cnt != info.nr_jited_func_lens)
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		return -1;
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	/* check BTF func info support */
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	if (info.btf_id && info.nr_func_info && info.func_info_rec_size) {
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		/* btf func info number should be same as sub_prog_cnt */
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		if (sub_prog_cnt != info.nr_func_info) {
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			pr_debug("%s: mismatch in BPF sub program count and BTF function info count, aborting\n", __func__);
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			return -1;
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		}
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		if (btf__get_from_id(info.btf_id, &btf)) {
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			pr_debug("%s: failed to get BTF of id %u, aborting\n", __func__, info.btf_id);
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			return -1;
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		}
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		func_info_rec_size = info.func_info_rec_size;
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		func_infos = calloc(sub_prog_cnt, func_info_rec_size);
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		if (!func_infos) {
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			pr_debug("%s: failed to allocate memory for func_infos, aborting\n", __func__);
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			return -1;
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		}
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		has_btf = true;
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	}
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	/*
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	 * We need address, length, and tag for each sub program.
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	 * Allocate memory and call bpf_obj_get_info_by_fd() again
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	 */
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	prog_addrs = calloc(sub_prog_cnt, sizeof(u64));
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	if (!prog_addrs) {
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		pr_debug("%s: failed to allocate memory for prog_addrs, aborting\n", __func__);
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		goto out;
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	}
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	prog_lens = calloc(sub_prog_cnt, sizeof(u32));
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	if (!prog_lens) {
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		pr_debug("%s: failed to allocate memory for prog_lens, aborting\n", __func__);
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		goto out;
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	}
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	prog_tags = calloc(sub_prog_cnt, BPF_TAG_SIZE);
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	if (!prog_tags) {
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		pr_debug("%s: failed to allocate memory for prog_tags, aborting\n", __func__);
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		goto out;
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	}
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	memset(&info, 0, sizeof(info));
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	info.nr_jited_ksyms = sub_prog_cnt;
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	info.nr_jited_func_lens = sub_prog_cnt;
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	info.nr_prog_tags = sub_prog_cnt;
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	info.jited_ksyms = ptr_to_u64(prog_addrs);
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	info.jited_func_lens = ptr_to_u64(prog_lens);
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	info.prog_tags = ptr_to_u64(prog_tags);
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	info_len = sizeof(info);
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	if (has_btf) {
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		info.nr_func_info = sub_prog_cnt;
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		info.func_info_rec_size = func_info_rec_size;
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		info.func_info = ptr_to_u64(func_infos);
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	}
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	err = bpf_obj_get_info_by_fd(fd, &info, &info_len);
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	if (err) {
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		||||
		pr_debug("%s: failed to get BPF program info, aborting\n", __func__);
 | 
			
		||||
		goto out;
 | 
			
		||||
	}
 | 
			
		||||
 | 
			
		||||
	/* Synthesize PERF_RECORD_KSYMBOL */
 | 
			
		||||
	for (i = 0; i < sub_prog_cnt; i++) {
 | 
			
		||||
		const struct bpf_func_info *finfo;
 | 
			
		||||
		const char *short_name = NULL;
 | 
			
		||||
		const struct btf_type *t;
 | 
			
		||||
		int name_len;
 | 
			
		||||
 | 
			
		||||
		*ksymbol_event = (struct ksymbol_event){
 | 
			
		||||
			.header = {
 | 
			
		||||
				.type = PERF_RECORD_KSYMBOL,
 | 
			
		||||
				.size = sizeof(struct ksymbol_event),
 | 
			
		||||
			},
 | 
			
		||||
			.addr = prog_addrs[i],
 | 
			
		||||
			.len = prog_lens[i],
 | 
			
		||||
			.ksym_type = PERF_RECORD_KSYMBOL_TYPE_BPF,
 | 
			
		||||
			.flags = 0,
 | 
			
		||||
		};
 | 
			
		||||
		name_len = snprintf(ksymbol_event->name, KSYM_NAME_LEN,
 | 
			
		||||
				    "bpf_prog_");
 | 
			
		||||
		name_len += snprintf_hex(ksymbol_event->name + name_len,
 | 
			
		||||
					 KSYM_NAME_LEN - name_len,
 | 
			
		||||
					 prog_tags[i], BPF_TAG_SIZE);
 | 
			
		||||
		if (has_btf) {
 | 
			
		||||
			finfo = func_infos + i * info.func_info_rec_size;
 | 
			
		||||
			t = btf__type_by_id(btf, finfo->type_id);
 | 
			
		||||
			short_name = btf__name_by_offset(btf, t->name_off);
 | 
			
		||||
		} else if (i == 0 && sub_prog_cnt == 1) {
 | 
			
		||||
			/* no subprog */
 | 
			
		||||
			if (info.name[0])
 | 
			
		||||
				short_name = info.name;
 | 
			
		||||
		} else
 | 
			
		||||
			short_name = "F";
 | 
			
		||||
		if (short_name)
 | 
			
		||||
			name_len += snprintf(ksymbol_event->name + name_len,
 | 
			
		||||
					     KSYM_NAME_LEN - name_len,
 | 
			
		||||
					     "_%s", short_name);
 | 
			
		||||
 | 
			
		||||
		ksymbol_event->header.size += PERF_ALIGN(name_len + 1,
 | 
			
		||||
							 sizeof(u64));
 | 
			
		||||
		err = perf_tool__process_synth_event(tool, event,
 | 
			
		||||
						     machine, process);
 | 
			
		||||
	}
 | 
			
		||||
 | 
			
		||||
	/* Synthesize PERF_RECORD_BPF_EVENT */
 | 
			
		||||
	if (opts->bpf_event) {
 | 
			
		||||
		*bpf_event = (struct bpf_event){
 | 
			
		||||
			.header = {
 | 
			
		||||
				.type = PERF_RECORD_BPF_EVENT,
 | 
			
		||||
				.size = sizeof(struct bpf_event),
 | 
			
		||||
			},
 | 
			
		||||
			.type = PERF_BPF_EVENT_PROG_LOAD,
 | 
			
		||||
			.flags = 0,
 | 
			
		||||
			.id = info.id,
 | 
			
		||||
		};
 | 
			
		||||
		memcpy(bpf_event->tag, prog_tags[i], BPF_TAG_SIZE);
 | 
			
		||||
		err = perf_tool__process_synth_event(tool, event,
 | 
			
		||||
						     machine, process);
 | 
			
		||||
	}
 | 
			
		||||
 | 
			
		||||
out:
 | 
			
		||||
	free(prog_tags);
 | 
			
		||||
	free(prog_lens);
 | 
			
		||||
	free(prog_addrs);
 | 
			
		||||
	free(func_infos);
 | 
			
		||||
	free(btf);
 | 
			
		||||
	return err ? -1 : 0;
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
int perf_event__synthesize_bpf_events(struct perf_tool *tool,
 | 
			
		||||
				      perf_event__handler_t process,
 | 
			
		||||
				      struct machine *machine,
 | 
			
		||||
				      struct record_opts *opts)
 | 
			
		||||
{
 | 
			
		||||
	union perf_event *event;
 | 
			
		||||
	__u32 id = 0;
 | 
			
		||||
	int err;
 | 
			
		||||
	int fd;
 | 
			
		||||
 | 
			
		||||
	event = malloc(sizeof(event->bpf_event) + KSYM_NAME_LEN);
 | 
			
		||||
	if (!event)
 | 
			
		||||
		return -1;
 | 
			
		||||
	while (true) {
 | 
			
		||||
		err = bpf_prog_get_next_id(id, &id);
 | 
			
		||||
		if (err) {
 | 
			
		||||
			if (errno == ENOENT) {
 | 
			
		||||
				err = 0;
 | 
			
		||||
				break;
 | 
			
		||||
			}
 | 
			
		||||
			pr_debug("%s: can't get next program: %s%s",
 | 
			
		||||
				 __func__, strerror(errno),
 | 
			
		||||
				 errno == EINVAL ? " -- kernel too old?" : "");
 | 
			
		||||
			/* don't report error on old kernel */
 | 
			
		||||
			err = (errno == EINVAL) ? 0 : -1;
 | 
			
		||||
			break;
 | 
			
		||||
		}
 | 
			
		||||
		fd = bpf_prog_get_fd_by_id(id);
 | 
			
		||||
		if (fd < 0) {
 | 
			
		||||
			pr_debug("%s: failed to get fd for prog_id %u\n",
 | 
			
		||||
				 __func__, id);
 | 
			
		||||
			continue;
 | 
			
		||||
		}
 | 
			
		||||
 | 
			
		||||
		err = perf_event__synthesize_one_bpf_prog(tool, process,
 | 
			
		||||
							  machine, fd,
 | 
			
		||||
							  event, opts);
 | 
			
		||||
		close(fd);
 | 
			
		||||
		if (err) {
 | 
			
		||||
			/* do not return error for old kernel */
 | 
			
		||||
			if (err == -2)
 | 
			
		||||
				err = 0;
 | 
			
		||||
			break;
 | 
			
		||||
		}
 | 
			
		||||
	}
 | 
			
		||||
	free(event);
 | 
			
		||||
	return err;
 | 
			
		||||
}
 | 
			
		||||
| 
						 | 
				
			
			
 | 
			
		|||
| 
						 | 
				
			
			@ -3,14 +3,22 @@
 | 
			
		|||
#define __PERF_BPF_EVENT_H
 | 
			
		||||
 | 
			
		||||
#include <linux/compiler.h>
 | 
			
		||||
#include "event.h"
 | 
			
		||||
 | 
			
		||||
struct machine;
 | 
			
		||||
union perf_event;
 | 
			
		||||
struct perf_sample;
 | 
			
		||||
struct perf_tool;
 | 
			
		||||
struct record_opts;
 | 
			
		||||
 | 
			
		||||
#ifdef HAVE_LIBBPF_SUPPORT
 | 
			
		||||
int machine__process_bpf_event(struct machine *machine, union perf_event *event,
 | 
			
		||||
			       struct perf_sample *sample);
 | 
			
		||||
 | 
			
		||||
int perf_event__synthesize_bpf_events(struct perf_tool *tool,
 | 
			
		||||
				      perf_event__handler_t process,
 | 
			
		||||
				      struct machine *machine,
 | 
			
		||||
				      struct record_opts *opts);
 | 
			
		||||
#else
 | 
			
		||||
static inline int machine__process_bpf_event(struct machine *machine __maybe_unused,
 | 
			
		||||
					     union perf_event *event __maybe_unused,
 | 
			
		||||
| 
						 | 
				
			
			@ -18,5 +26,13 @@ static inline int machine__process_bpf_event(struct machine *machine __maybe_unu
 | 
			
		|||
{
 | 
			
		||||
	return 0;
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
static inline int perf_event__synthesize_bpf_events(struct perf_tool *tool __maybe_unused,
 | 
			
		||||
						    perf_event__handler_t process __maybe_unused,
 | 
			
		||||
						    struct machine *machine __maybe_unused,
 | 
			
		||||
						    struct record_opts *opts __maybe_unused)
 | 
			
		||||
{
 | 
			
		||||
	return 0;
 | 
			
		||||
}
 | 
			
		||||
#endif // HAVE_LIBBPF_SUPPORT
 | 
			
		||||
#endif
 | 
			
		||||
| 
						 | 
				
			
			
 | 
			
		|||
		Loading…
	
		Reference in a new issue