Re: [PATCH v2 perf,bpf 05/11] perf, bpf: save bpf_prog_info in a rbtree in perf_env

From: Song Liu
Date: Fri Feb 15 2019 - 12:05:06 EST

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In reply to: Arnaldo Carvalho de Melo: "Re: [PATCH v2 perf,bpf 05/11] perf, bpf: save bpf_prog_info in a rbtree in perf_env"
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> On Feb 15, 2019, at 6:21 AM, Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> wrote:
>
> Em Thu, Feb 14, 2019 at 04:00:06PM -0800, Song Liu escreveu:
>> bpf_prog_info contains information necessary to annotate bpf programs.
>> This patch saves bpf_prog_info for bpf programs loaded in the system.
>>
>> Signed-off-by: Song Liu <songliubraving@xxxxxx>
>> ---
>> tools/perf/builtin-record.c | 2 +-
>> tools/perf/builtin-top.c | 2 +-
>> tools/perf/util/bpf-event.c | 39 +++++++++++++----
>> tools/perf/util/bpf-event.h | 15 +++++--
>> tools/perf/util/env.c | 83 +++++++++++++++++++++++++++++++++++++
>> tools/perf/util/env.h | 14 +++++++
>> 6 files changed, 142 insertions(+), 13 deletions(-)
>>
>> diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
>> index 88ea11d57c6f..2355e0a9eda0 100644
>> --- a/tools/perf/builtin-record.c
>> +++ b/tools/perf/builtin-record.c
>> @@ -1083,7 +1083,7 @@ static int record__synthesize(struct record *rec, bool tail)
>> return err;
>> }
>>
>> - err = perf_event__synthesize_bpf_events(tool, process_synthesized_event,
>> + err = perf_event__synthesize_bpf_events(session, process_synthesized_event,
>> machine, opts);
>> if (err < 0)
>> pr_warning("Couldn't synthesize bpf events.\n");
>> diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
>> index 5a486d4de56e..27d8d42e0a4d 100644
>> --- a/tools/perf/builtin-top.c
>> +++ b/tools/perf/builtin-top.c
>> @@ -1216,7 +1216,7 @@ static int __cmd_top(struct perf_top *top)
>>
>> init_process_thread(top);
>>
>> - ret = perf_event__synthesize_bpf_events(&top->tool, perf_event__process,
>> + ret = perf_event__synthesize_bpf_events(top->session, perf_event__process,
>> &top->session->machines.host,
>> &top->record_opts);
>> if (ret < 0)
>> diff --git a/tools/perf/util/bpf-event.c b/tools/perf/util/bpf-event.c
>> index e6dfb95029e5..ead599bc4f4e 100644
>> --- a/tools/perf/util/bpf-event.c
>> +++ b/tools/perf/util/bpf-event.c
>> @@ -1,15 +1,13 @@
>> // SPDX-License-Identifier: GPL-2.0
>> #include <errno.h>
>> #include <stdlib.h>
>> -#include <bpf/bpf.h>
>> -#include <bpf/btf.h>
>> -#include <bpf/libbpf.h>
>> -#include <linux/btf.h>
>
> I think you need these here, since in this C file you will use the
> definitions for these structs, see further comments below.
>
>> #include <linux/err.h>
>> #include "bpf-event.h"
>> #include "debug.h"
>> #include "symbol.h"
>> #include "machine.h"
>> +#include "env.h"
>> +#include "session.h"
>>
>> #define ptr_to_u64(ptr) ((__u64)(unsigned long)(ptr))
>>
>> @@ -42,7 +40,7 @@ int machine__process_bpf_event(struct machine *machine __maybe_unused,
>> * -1 for failures;
>> * -2 for lack of kernel support.
>> */
>> -static int perf_event__synthesize_one_bpf_prog(struct perf_tool *tool,
>> +static int perf_event__synthesize_one_bpf_prog(struct perf_session *session,
>> perf_event__handler_t process,
>> struct machine *machine,
>> int fd,
>> @@ -52,17 +50,29 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_tool *tool,
>> struct ksymbol_event *ksymbol_event = &event->ksymbol_event;
>> struct bpf_event *bpf_event = &event->bpf_event;
>> struct bpf_prog_info_linear *info_linear;
>> + struct perf_tool *tool = session->tool;
>> + struct bpf_prog_info_node *info_node;
>> struct bpf_prog_info *info;
>> struct btf *btf = NULL;
>> bool has_btf = false;
>> + struct perf_env *env;
>> u32 sub_prog_cnt, i;
>> int err = 0;
>> u64 arrays;
>>
>> + /*
>> + * for perf-record and perf-report use header.env;
>> + * otherwise, use global perf_env.
>> + */
>> + env = session->data ? &session->header.env : &perf_env;
>> +
>> arrays = 1UL << BPF_PROG_INFO_JITED_KSYMS;
>> arrays |= 1UL << BPF_PROG_INFO_JITED_FUNC_LENS;
>> arrays |= 1UL << BPF_PROG_INFO_FUNC_INFO;
>> arrays |= 1UL << BPF_PROG_INFO_PROG_TAGS;
>> + arrays |= 1UL << BPF_PROG_INFO_JITED_INSNS;
>> + arrays |= 1UL << BPF_PROG_INFO_LINE_INFO;
>> + arrays |= 1UL << BPF_PROG_INFO_JITED_LINE_INFO;
>>
>> info_linear = bpf_program__get_prog_info_linear(fd, arrays);
>> if (IS_ERR_OR_NULL(info_linear)) {
>> @@ -151,8 +161,8 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_tool *tool,
>> machine, process);
>> }
>>
>> - /* Synthesize PERF_RECORD_BPF_EVENT */
>> if (opts->bpf_event) {
>> + /* Synthesize PERF_RECORD_BPF_EVENT */
>> *bpf_event = (struct bpf_event){
>> .header = {
>> .type = PERF_RECORD_BPF_EVENT,
>> @@ -165,6 +175,19 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_tool *tool,
>> memcpy(bpf_event->tag, info->tag, BPF_TAG_SIZE);
>> memset((void *)event + event->header.size, 0, machine->id_hdr_size);
>> event->header.size += machine->id_hdr_size;
>> +
>> + /* save bpf_prog_info to env */
>> + info_node = malloc(sizeof(struct bpf_prog_info_node));
>> + if (info_node) {
>> + info_node->info_linear = info_linear;
>> + perf_env__insert_bpf_prog_info(env, info_node);
>> + info_linear = NULL;
>> + }
>> +
>> + /*
>> + * process after saving bpf_prog_info to env, so that
>> + * required information is ready for look up
>> + */
>> err = perf_tool__process_synth_event(tool, event,
>> machine, process);
>> }
>> @@ -175,7 +198,7 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_tool *tool,
>> return err ? -1 : 0;
>> }
>>
>> -int perf_event__synthesize_bpf_events(struct perf_tool *tool,
>> +int perf_event__synthesize_bpf_events(struct perf_session *session,
>> perf_event__handler_t process,
>> struct machine *machine,
>> struct record_opts *opts)
>> @@ -209,7 +232,7 @@ int perf_event__synthesize_bpf_events(struct perf_tool *tool,
>> continue;
>> }
>>
>> - err = perf_event__synthesize_one_bpf_prog(tool, process,
>> + err = perf_event__synthesize_one_bpf_prog(session, process,
>> machine, fd,
>> event, opts);
>> close(fd);
>> diff --git a/tools/perf/util/bpf-event.h b/tools/perf/util/bpf-event.h
>> index 7890067e1a37..11e6730b6105 100644
>> --- a/tools/perf/util/bpf-event.h
>> +++ b/tools/perf/util/bpf-event.h
>> @@ -3,19 +3,28 @@
>> #define __PERF_BPF_EVENT_H
>>
>> #include <linux/compiler.h>
>> +#include <bpf/bpf.h>
>> +#include <bpf/btf.h>
>> +#include <bpf/libbpf.h>
>> +#include <linux/btf.h>
>
> Are you sure you'll need all of these headers here? Perhaps just some
> forward declarations will do?
>
> In fact the only bpf or btf structure here seems to be
> bpf_prog_info_linear, which needs ust a forward declaration.
>
> Avoiding these includes reduces the build time, and since the build-test
> target does many builds and I want to build this in many containers, we
> should try to reduce the build time by using just what is needed in each
> header and C file. Also during development it helps with not rebuilding
> tons of things when something unrelated changes in a header, etc.

I see. I will fix this in next version.

>
> - Arnaldo
>
>> +#include <linux/rbtree.h>
>> #include "event.h"
>>
>> struct machine;
>> union perf_event;
>> struct perf_sample;
>> -struct perf_tool;
>> struct record_opts;
>>
>> +struct bpf_prog_info_node {
>> + struct bpf_prog_info_linear *info_linear;
>> + struct rb_node rb_node;
>> +};
>> +
>> #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,
>> +int perf_event__synthesize_bpf_events(struct perf_session *session,
>> perf_event__handler_t process,
>> struct machine *machine,
>> struct record_opts *opts);
>> @@ -27,7 +36,7 @@ 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,
>> +static inline int perf_event__synthesize_bpf_events(struct perf_session *session __maybe_unused,
>> perf_event__handler_t process __maybe_unused,
>> struct machine *machine __maybe_unused,
>> struct record_opts *opts __maybe_unused)
>> diff --git a/tools/perf/util/env.c b/tools/perf/util/env.c
>> index 4c23779e271a..665b6fe3c7b2 100644
>> --- a/tools/perf/util/env.c
>> +++ b/tools/perf/util/env.c
>> @@ -8,10 +8,86 @@
>>
>> struct perf_env perf_env;
>>
>> +void perf_env__insert_bpf_prog_info(struct perf_env *env,
>> + struct bpf_prog_info_node *info_node)
>> +{
>> + __u32 prog_id = info_node->info_linear->info.id;
>> + struct bpf_prog_info_node *node;
>> + struct rb_node *parent = NULL;
>> + struct rb_node **p;
>> +
>> + down_write(&env->bpf_info_lock);
>> + p = &env->bpf_prog_infos.rb_node;
>> +
>> + while (*p != NULL) {
>> + parent = *p;
>> + node = rb_entry(parent, struct bpf_prog_info_node, rb_node);
>> + if (prog_id < node->info_linear->info.id) {
>> + p = &(*p)->rb_left;
>> + } else if (prog_id > node->info_linear->info.id) {
>> + p = &(*p)->rb_right;
>> + } else {
>> + pr_debug("duplicated bpf prog info %u\n", prog_id);
>> + up_write(&env->bpf_info_lock);
>> + return;
>> + }
>> + }
>> +
>> + rb_link_node(&info_node->rb_node, parent, p);
>> + rb_insert_color(&info_node->rb_node, &env->bpf_prog_infos);
>> + up_write(&env->bpf_info_lock);
>> +}
>> +
>> +struct bpf_prog_info_node *perf_env__find_bpf_prog_info(struct perf_env *env,
>> + __u32 prog_id)
>> +{
>> + struct bpf_prog_info_node *node = NULL;
>> + struct rb_node *n;
>> +
>> + down_read(&env->bpf_info_lock);
>> + n = env->bpf_prog_infos.rb_node;
>> +
>> + while (n) {
>> + node = rb_entry(n, struct bpf_prog_info_node, rb_node);
>> + if (prog_id < node->info_linear->info.id)
>> + n = n->rb_left;
>> + else if (prog_id > node->info_linear->info.id)
>> + n = n->rb_right;
>> + else
>> + break;
>> + }
>> +
>> + up_read(&env->bpf_info_lock);
>> + return node;
>> +}
>> +
>> +/* purge data in bpf_prog_infos tree */
>> +static void purge_bpf_info(struct perf_env *env)
>> +{
>> + struct rb_root *root;
>> + struct rb_node *next;
>> +
>> + down_write(&env->bpf_info_lock);
>> +
>> + root = &env->bpf_prog_infos;
>> + next = rb_first(root);
>> +
>> + while (next) {
>> + struct bpf_prog_info_node *node;
>> +
>> + node = rb_entry(next, struct bpf_prog_info_node, rb_node);
>> + next = rb_next(&node->rb_node);
>> + rb_erase_init(&node->rb_node, root);
>> + free(node);
>> + }
>> + up_write(&env->bpf_info_lock);
>> +}
>> +
>> void perf_env__exit(struct perf_env *env)
>> {
>> int i;
>>
>> + purge_bpf_info(env);
>> zfree(&env->hostname);
>> zfree(&env->os_release);
>> zfree(&env->version);
>> @@ -38,6 +114,12 @@ void perf_env__exit(struct perf_env *env)
>> zfree(&env->memory_nodes);
>> }
>>
>> +static void init_bpf_rb_trees(struct perf_env *env)
>> +{
>> + env->bpf_prog_infos = RB_ROOT;
>> + init_rwsem(&env->bpf_info_lock);
>> +}
>> +
>> int perf_env__set_cmdline(struct perf_env *env, int argc, const char *argv[])
>> {
>> int i;
>> @@ -59,6 +141,7 @@ int perf_env__set_cmdline(struct perf_env *env, int argc, const char *argv[])
>>
>> env->nr_cmdline = argc;
>>
>> + init_bpf_rb_trees(env);
>> return 0;
>> out_free:
>> zfree(&env->cmdline_argv);
>> diff --git a/tools/perf/util/env.h b/tools/perf/util/env.h
>> index d01b8355f4ca..a6d25e91bc98 100644
>> --- a/tools/perf/util/env.h
>> +++ b/tools/perf/util/env.h
>> @@ -3,7 +3,10 @@
>> #define __PERF_ENV_H
>>
>> #include <linux/types.h>
>> +#include <linux/rbtree.h>
>> #include "cpumap.h"
>> +#include "rwsem.h"
>
> You don't need the following header, just use a forward declaration for
> the sole struct you use with a pointer:
>
> struct bpf_prog_info_node;
>
>> +#include "bpf-event.h"
>>
>> struct cpu_topology_map {
>> int socket_id;
>> @@ -64,6 +67,13 @@ struct perf_env {
>> struct memory_node *memory_nodes;
>> unsigned long long memory_bsize;
>> u64 clockid_res_ns;
>> +
>> + /*
>> + * bpf_info_lock protects bpf rbtrees. This is needed because the
>> + * trees are accessed by different threads in perf-top
>> + */
>> + struct rw_semaphore bpf_info_lock;
>> + struct rb_root bpf_prog_infos;
>
> Please group this into a structure, i.e.:
>
> struct {
> struct rw_semaphore lock;
> struct rb_root infos;
> } bpf_progs;

Will fix this in next version.

>
>> };
>>
>> extern struct perf_env perf_env;
>> @@ -80,4 +90,8 @@ const char *perf_env__arch(struct perf_env *env);
>> const char *perf_env__raw_arch(struct perf_env *env);
>> int perf_env__nr_cpus_avail(struct perf_env *env);
>>
>> +void perf_env__insert_bpf_prog_info(struct perf_env *env,
>> + struct bpf_prog_info_node *info_node);
>> +struct bpf_prog_info_node *perf_env__find_bpf_prog_info(struct perf_env *env,
>> + __u32 prog_id);
>> #endif /* __PERF_ENV_H */
>> --
>> 2.17.1

Next message: Gustavo A. R. Silva: "[PATCH] drm/drm_vm: Mark expected switch fall-throughs"
Previous message: Steven Price: "[PATCH 05/13] mm: pagewalk: Allow walking without vma"
In reply to: Arnaldo Carvalho de Melo: "Re: [PATCH v2 perf,bpf 05/11] perf, bpf: save bpf_prog_info in a rbtree in perf_env"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]