blob: 7d180bdaedbc9ec374e251e5a69229b03033c8d6 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/*
* dlfilter.c: Interface to perf script --dlfilter shared object
* Copyright (c) 2021, Intel Corporation.
*/
#include <dlfcn.h>
#include <stdlib.h>
#include <string.h>
#include <dirent.h>
#include <subcmd/exec-cmd.h>
#include <linux/zalloc.h>
#include <linux/build_bug.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include "debug.h"
#include "event.h"
#include "evsel.h"
#include "dso.h"
#include "map.h"
#include "thread.h"
#include "trace-event.h"
#include "symbol.h"
#include "srcline.h"
#include "dlfilter.h"
#include "../include/perf/perf_dlfilter.h"
static void al_to_d_al(struct addr_location *al, struct perf_dlfilter_al *d_al)
{
struct symbol *sym = al->sym;
d_al->size = sizeof(*d_al);
if (al->map) {
struct dso *dso = map__dso(al->map);
if (symbol_conf.show_kernel_path && dso__long_name(dso))
d_al->dso = dso__long_name(dso);
else
d_al->dso = dso__name(dso);
d_al->is_64_bit = dso__is_64_bit(dso);
d_al->buildid_size = dso__bid(dso)->size;
d_al->buildid = dso__bid(dso)->data;
} else {
d_al->dso = NULL;
d_al->is_64_bit = 0;
d_al->buildid_size = 0;
d_al->buildid = NULL;
}
if (sym) {
d_al->sym = sym->name;
d_al->sym_start = sym->start;
d_al->sym_end = sym->end;
if (al->addr < sym->end)
d_al->symoff = al->addr - sym->start;
else if (al->map)
d_al->symoff = al->addr - map__start(al->map) - sym->start;
else
d_al->symoff = 0;
d_al->sym_binding = sym->binding;
} else {
d_al->sym = NULL;
d_al->sym_start = 0;
d_al->sym_end = 0;
d_al->symoff = 0;
d_al->sym_binding = 0;
}
d_al->addr = al->addr;
d_al->comm = NULL;
d_al->filtered = 0;
d_al->priv = NULL;
}
static struct addr_location *get_al(struct dlfilter *d)
{
struct addr_location *al = d->al;
if (!al->thread && machine__resolve(d->machine, al, d->sample) < 0)
return NULL;
return al;
}
static struct thread *get_thread(struct dlfilter *d)
{
struct addr_location *al = get_al(d);
return al ? al->thread : NULL;
}
static const struct perf_dlfilter_al *dlfilter__resolve_ip(void *ctx)
{
struct dlfilter *d = (struct dlfilter *)ctx;
struct perf_dlfilter_al *d_al = d->d_ip_al;
struct addr_location *al;
if (!d->ctx_valid)
return NULL;
/* 'size' is also used to indicate already initialized */
if (d_al->size)
return d_al;
al = get_al(d);
if (!al)
return NULL;
al_to_d_al(al, d_al);
d_al->is_kernel_ip = machine__kernel_ip(d->machine, d->sample->ip);
d_al->comm = al->thread ? thread__comm_str(al->thread) : ":-1";
d_al->filtered = al->filtered;
return d_al;
}
static const struct perf_dlfilter_al *dlfilter__resolve_addr(void *ctx)
{
struct dlfilter *d = (struct dlfilter *)ctx;
struct perf_dlfilter_al *d_addr_al = d->d_addr_al;
struct addr_location *addr_al = d->addr_al;
if (!d->ctx_valid || !d->d_sample->addr_correlates_sym)
return NULL;
/* 'size' is also used to indicate already initialized */
if (d_addr_al->size)
return d_addr_al;
if (!addr_al->thread) {
struct thread *thread = get_thread(d);
if (!thread)
return NULL;
thread__resolve(thread, addr_al, d->sample);
}
al_to_d_al(addr_al, d_addr_al);
d_addr_al->is_kernel_ip = machine__kernel_ip(d->machine, d->sample->addr);
return d_addr_al;
}
static char **dlfilter__args(void *ctx, int *dlargc)
{
struct dlfilter *d = (struct dlfilter *)ctx;
if (dlargc)
*dlargc = 0;
else
return NULL;
if (!d->ctx_valid && !d->in_start && !d->in_stop)
return NULL;
*dlargc = d->dlargc;
return d->dlargv;
}
static bool has_priv(struct perf_dlfilter_al *d_al_p)
{
return d_al_p->size >= offsetof(struct perf_dlfilter_al, priv) + sizeof(d_al_p->priv);
}
static __s32 dlfilter__resolve_address(void *ctx, __u64 address, struct perf_dlfilter_al *d_al_p)
{
struct dlfilter *d = (struct dlfilter *)ctx;
struct perf_dlfilter_al d_al;
struct addr_location al;
struct thread *thread;
__u32 sz;
if (!d->ctx_valid || !d_al_p)
return -1;
thread = get_thread(d);
if (!thread)
return -1;
addr_location__init(&al);
thread__find_symbol_fb(thread, d->sample->cpumode, address, &al);
al_to_d_al(&al, &d_al);
d_al.is_kernel_ip = machine__kernel_ip(d->machine, address);
sz = d_al_p->size;
memcpy(d_al_p, &d_al, min((size_t)sz, sizeof(d_al)));
d_al_p->size = sz;
if (has_priv(d_al_p))
d_al_p->priv = memdup(&al, sizeof(al));
else /* Avoid leak for v0 API */
addr_location__exit(&al);
return 0;
}
static void dlfilter__al_cleanup(void *ctx __maybe_unused, struct perf_dlfilter_al *d_al_p)
{
struct addr_location *al;
/* Ensure backward compatibility */
if (!has_priv(d_al_p) || !d_al_p->priv)
return;
al = d_al_p->priv;
d_al_p->priv = NULL;
addr_location__exit(al);
free(al);
}
static const __u8 *dlfilter__insn(void *ctx, __u32 *len)
{
struct dlfilter *d = (struct dlfilter *)ctx;
if (!len)
return NULL;
*len = 0;
if (!d->ctx_valid)
return NULL;
if (d->sample->ip && !d->sample->insn_len) {
struct addr_location *al = d->al;
if (!al->thread && machine__resolve(d->machine, al, d->sample) < 0)
return NULL;
if (thread__maps(al->thread)) {
struct machine *machine = maps__machine(thread__maps(al->thread));
if (machine)
script_fetch_insn(d->sample, al->thread, machine);
}
}
if (!d->sample->insn_len)
return NULL;
*len = d->sample->insn_len;
return (__u8 *)d->sample->insn;
}
static const char *dlfilter__srcline(void *ctx, __u32 *line_no)
{
struct dlfilter *d = (struct dlfilter *)ctx;
struct addr_location *al;
unsigned int line = 0;
char *srcfile = NULL;
struct map *map;
struct dso *dso;
u64 addr;
if (!d->ctx_valid || !line_no)
return NULL;
al = get_al(d);
if (!al)
return NULL;
map = al->map;
addr = al->addr;
dso = map ? map__dso(map) : NULL;
if (dso)
srcfile = get_srcline_split(dso, map__rip_2objdump(map, addr), &line);
*line_no = line;
return srcfile;
}
static struct perf_event_attr *dlfilter__attr(void *ctx)
{
struct dlfilter *d = (struct dlfilter *)ctx;
if (!d->ctx_valid)
return NULL;
return &d->evsel->core.attr;
}
static __s32 code_read(__u64 ip, struct map *map, struct machine *machine, void *buf, __u32 len)
{
u64 offset = map__map_ip(map, ip);
if (ip + len >= map__end(map))
len = map__end(map) - ip;
return dso__data_read_offset(map__dso(map), machine, offset, buf, len);
}
static __s32 dlfilter__object_code(void *ctx, __u64 ip, void *buf, __u32 len)
{
struct dlfilter *d = (struct dlfilter *)ctx;
struct addr_location *al;
struct addr_location a;
__s32 ret;
if (!d->ctx_valid)
return -1;
al = get_al(d);
if (!al)
return -1;
if (al->map && ip >= map__start(al->map) && ip < map__end(al->map) &&
machine__kernel_ip(d->machine, ip) == machine__kernel_ip(d->machine, d->sample->ip))
return code_read(ip, al->map, d->machine, buf, len);
addr_location__init(&a);
thread__find_map_fb(al->thread, d->sample->cpumode, ip, &a);
ret = a.map ? code_read(ip, a.map, d->machine, buf, len) : -1;
addr_location__exit(&a);
return ret;
}
static const struct perf_dlfilter_fns perf_dlfilter_fns = {
.resolve_ip = dlfilter__resolve_ip,
.resolve_addr = dlfilter__resolve_addr,
.args = dlfilter__args,
.resolve_address = dlfilter__resolve_address,
.al_cleanup = dlfilter__al_cleanup,
.insn = dlfilter__insn,
.srcline = dlfilter__srcline,
.attr = dlfilter__attr,
.object_code = dlfilter__object_code,
};
static char *find_dlfilter(const char *file)
{
char path[PATH_MAX];
char *exec_path;
if (strchr(file, '/'))
goto out;
if (!access(file, R_OK)) {
/*
* Prepend "./" so that dlopen will find the file in the
* current directory.
*/
snprintf(path, sizeof(path), "./%s", file);
file = path;
goto out;
}
exec_path = get_argv_exec_path();
if (!exec_path)
goto out;
snprintf(path, sizeof(path), "%s/dlfilters/%s", exec_path, file);
free(exec_path);
if (!access(path, R_OK))
file = path;
out:
return strdup(file);
}
#define CHECK_FLAG(x) BUILD_BUG_ON((u64)PERF_DLFILTER_FLAG_ ## x != (u64)PERF_IP_FLAG_ ## x)
static int dlfilter__init(struct dlfilter *d, const char *file, int dlargc, char **dlargv)
{
CHECK_FLAG(BRANCH);
CHECK_FLAG(CALL);
CHECK_FLAG(RETURN);
CHECK_FLAG(CONDITIONAL);
CHECK_FLAG(SYSCALLRET);
CHECK_FLAG(ASYNC);
CHECK_FLAG(INTERRUPT);
CHECK_FLAG(TX_ABORT);
CHECK_FLAG(TRACE_BEGIN);
CHECK_FLAG(TRACE_END);
CHECK_FLAG(IN_TX);
CHECK_FLAG(VMENTRY);
CHECK_FLAG(VMEXIT);
memset(d, 0, sizeof(*d));
d->file = find_dlfilter(file);
if (!d->file)
return -1;
d->dlargc = dlargc;
d->dlargv = dlargv;
return 0;
}
static void dlfilter__exit(struct dlfilter *d)
{
zfree(&d->file);
}
static int dlfilter__open(struct dlfilter *d)
{
d->handle = dlopen(d->file, RTLD_NOW);
if (!d->handle) {
pr_err("dlopen failed for: '%s'\n", d->file);
return -1;
}
d->start = dlsym(d->handle, "start");
d->filter_event = dlsym(d->handle, "filter_event");
d->filter_event_early = dlsym(d->handle, "filter_event_early");
d->stop = dlsym(d->handle, "stop");
d->fns = dlsym(d->handle, "perf_dlfilter_fns");
if (d->fns)
memcpy(d->fns, &perf_dlfilter_fns, sizeof(struct perf_dlfilter_fns));
return 0;
}
static int dlfilter__close(struct dlfilter *d)
{
return dlclose(d->handle);
}
struct dlfilter *dlfilter__new(const char *file, int dlargc, char **dlargv)
{
struct dlfilter *d = malloc(sizeof(*d));
if (!d)
return NULL;
if (dlfilter__init(d, file, dlargc, dlargv))
goto err_free;
if (dlfilter__open(d))
goto err_exit;
return d;
err_exit:
dlfilter__exit(d);
err_free:
free(d);
return NULL;
}
static void dlfilter__free(struct dlfilter *d)
{
if (d) {
dlfilter__exit(d);
free(d);
}
}
int dlfilter__start(struct dlfilter *d, struct perf_session *session)
{
if (d) {
d->session = session;
if (d->start) {
int ret;
d->in_start = true;
ret = d->start(&d->data, d);
d->in_start = false;
return ret;
}
}
return 0;
}
static int dlfilter__stop(struct dlfilter *d)
{
if (d && d->stop) {
int ret;
d->in_stop = true;
ret = d->stop(d->data, d);
d->in_stop = false;
return ret;
}
return 0;
}
void dlfilter__cleanup(struct dlfilter *d)
{
if (d) {
dlfilter__stop(d);
dlfilter__close(d);
dlfilter__free(d);
}
}
#define ASSIGN(x) d_sample.x = sample->x
int dlfilter__do_filter_event(struct dlfilter *d,
union perf_event *event,
struct perf_sample *sample,
struct evsel *evsel,
struct machine *machine,
struct addr_location *al,
struct addr_location *addr_al,
bool early)
{
struct perf_dlfilter_sample d_sample;
struct perf_dlfilter_al d_ip_al;
struct perf_dlfilter_al d_addr_al;
int ret;
d->event = event;
d->sample = sample;
d->evsel = evsel;
d->machine = machine;
d->al = al;
d->addr_al = addr_al;
d->d_sample = &d_sample;
d->d_ip_al = &d_ip_al;
d->d_addr_al = &d_addr_al;
d_sample.size = sizeof(d_sample);
d_ip_al.size = 0; /* To indicate d_ip_al is not initialized */
d_addr_al.size = 0; /* To indicate d_addr_al is not initialized */
ASSIGN(ip);
ASSIGN(pid);
ASSIGN(tid);
ASSIGN(time);
ASSIGN(addr);
ASSIGN(id);
ASSIGN(stream_id);
ASSIGN(period);
ASSIGN(weight);
ASSIGN(ins_lat);
ASSIGN(p_stage_cyc);
ASSIGN(transaction);
ASSIGN(insn_cnt);
ASSIGN(cyc_cnt);
ASSIGN(cpu);
ASSIGN(flags);
ASSIGN(data_src);
ASSIGN(phys_addr);
ASSIGN(data_page_size);
ASSIGN(code_page_size);
ASSIGN(cgroup);
ASSIGN(cpumode);
ASSIGN(misc);
ASSIGN(raw_size);
ASSIGN(raw_data);
ASSIGN(machine_pid);
ASSIGN(vcpu);
if (sample->branch_stack) {
d_sample.brstack_nr = sample->branch_stack->nr;
d_sample.brstack = (struct perf_branch_entry *)perf_sample__branch_entries(sample);
} else {
d_sample.brstack_nr = 0;
d_sample.brstack = NULL;
}
if (sample->callchain) {
d_sample.raw_callchain_nr = sample->callchain->nr;
d_sample.raw_callchain = (__u64 *)sample->callchain->ips;
} else {
d_sample.raw_callchain_nr = 0;
d_sample.raw_callchain = NULL;
}
d_sample.addr_correlates_sym =
(evsel->core.attr.sample_type & PERF_SAMPLE_ADDR) &&
sample_addr_correlates_sym(&evsel->core.attr);
d_sample.event = evsel__name(evsel);
d->ctx_valid = true;
if (early)
ret = d->filter_event_early(d->data, &d_sample, d);
else
ret = d->filter_event(d->data, &d_sample, d);
d->ctx_valid = false;
return ret;
}
bool get_filter_desc(const char *dirname, const char *name, char **desc,
char **long_desc)
{
char path[PATH_MAX];
void *handle;
const char *(*desc_fn)(const char **long_description);
snprintf(path, sizeof(path), "%s/%s", dirname, name);
handle = dlopen(path, RTLD_NOW);
if (!handle || !(dlsym(handle, "filter_event") || dlsym(handle, "filter_event_early")))
return false;
desc_fn = dlsym(handle, "filter_description");
if (desc_fn) {
const char *dsc;
const char *long_dsc;
dsc = desc_fn(&long_dsc);
if (dsc)
*desc = strdup(dsc);
if (long_dsc)
*long_desc = strdup(long_dsc);
}
dlclose(handle);
return true;
}
static void list_filters(const char *dirname)
{
struct dirent *entry;
DIR *dir;
dir = opendir(dirname);
if (!dir)
return;
while ((entry = readdir(dir)) != NULL)
{
size_t n = strlen(entry->d_name);
char *long_desc = NULL;
char *desc = NULL;
if (entry->d_type == DT_DIR || n < 4 ||
strcmp(".so", entry->d_name + n - 3))
continue;
if (!get_filter_desc(dirname, entry->d_name, &desc, &long_desc))
continue;
printf(" %-36s %s\n", entry->d_name, desc ? desc : "");
if (verbose > 0) {
char *p = long_desc;
char *line;
while ((line = strsep(&p, "\n")) != NULL)
printf("%39s%s\n", "", line);
}
free(long_desc);
free(desc);
}
closedir(dir);
}
int list_available_dlfilters(const struct option *opt __maybe_unused,
const char *s __maybe_unused,
int unset __maybe_unused)
{
char path[PATH_MAX];
char *exec_path;
printf("List of available dlfilters:\n");
list_filters(".");
exec_path = get_argv_exec_path();
if (!exec_path)
goto out;
snprintf(path, sizeof(path), "%s/dlfilters", exec_path);
list_filters(path);
free(exec_path);
out:
exit(0);
}