forked from Minki/linux
eb9f03231b
It _will_ be used, no sense in receiving it and nor fowarding it along. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Hemant Kumar <hemant@linux.vnet.ibm.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Cc: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-ht8v5et209wuoh5o6nh9pzyq@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
202 lines
4.4 KiB
C
202 lines
4.4 KiB
C
#include <linux/compiler.h>
|
|
#include <linux/types.h>
|
|
#include <unistd.h>
|
|
#include "tests.h"
|
|
#include "debug.h"
|
|
#include "machine.h"
|
|
#include "event.h"
|
|
#include "unwind.h"
|
|
#include "perf_regs.h"
|
|
#include "map.h"
|
|
#include "thread.h"
|
|
#include "callchain.h"
|
|
|
|
#if defined (__x86_64__) || defined (__i386__)
|
|
#include "arch-tests.h"
|
|
#endif
|
|
|
|
/* For bsearch. We try to unwind functions in shared object. */
|
|
#include <stdlib.h>
|
|
|
|
static int mmap_handler(struct perf_tool *tool __maybe_unused,
|
|
union perf_event *event,
|
|
struct perf_sample *sample,
|
|
struct machine *machine)
|
|
{
|
|
return machine__process_mmap2_event(machine, event, sample);
|
|
}
|
|
|
|
static int init_live_machine(struct machine *machine)
|
|
{
|
|
union perf_event event;
|
|
pid_t pid = getpid();
|
|
|
|
return perf_event__synthesize_mmap_events(NULL, &event, pid, pid,
|
|
mmap_handler, machine, true, 500);
|
|
}
|
|
|
|
#define MAX_STACK 8
|
|
|
|
static int unwind_entry(struct unwind_entry *entry, void *arg)
|
|
{
|
|
unsigned long *cnt = (unsigned long *) arg;
|
|
char *symbol = entry->sym ? entry->sym->name : NULL;
|
|
static const char *funcs[MAX_STACK] = {
|
|
"test__arch_unwind_sample",
|
|
"unwind_thread",
|
|
"compare",
|
|
"bsearch",
|
|
"krava_3",
|
|
"krava_2",
|
|
"krava_1",
|
|
"test__dwarf_unwind"
|
|
};
|
|
/*
|
|
* The funcs[MAX_STACK] array index, based on the
|
|
* callchain order setup.
|
|
*/
|
|
int idx = callchain_param.order == ORDER_CALLER ?
|
|
MAX_STACK - *cnt - 1 : *cnt;
|
|
|
|
if (*cnt >= MAX_STACK) {
|
|
pr_debug("failed: crossed the max stack value %d\n", MAX_STACK);
|
|
return -1;
|
|
}
|
|
|
|
if (!symbol) {
|
|
pr_debug("failed: got unresolved address 0x%" PRIx64 "\n",
|
|
entry->ip);
|
|
return -1;
|
|
}
|
|
|
|
(*cnt)++;
|
|
pr_debug("got: %s 0x%" PRIx64 ", expecting %s\n",
|
|
symbol, entry->ip, funcs[idx]);
|
|
return strcmp((const char *) symbol, funcs[idx]);
|
|
}
|
|
|
|
__attribute__ ((noinline))
|
|
static int unwind_thread(struct thread *thread)
|
|
{
|
|
struct perf_sample sample;
|
|
unsigned long cnt = 0;
|
|
int err = -1;
|
|
|
|
memset(&sample, 0, sizeof(sample));
|
|
|
|
if (test__arch_unwind_sample(&sample, thread)) {
|
|
pr_debug("failed to get unwind sample\n");
|
|
goto out;
|
|
}
|
|
|
|
err = unwind__get_entries(unwind_entry, &cnt, thread,
|
|
&sample, MAX_STACK);
|
|
if (err)
|
|
pr_debug("unwind failed\n");
|
|
else if (cnt != MAX_STACK) {
|
|
pr_debug("got wrong number of stack entries %lu != %d\n",
|
|
cnt, MAX_STACK);
|
|
err = -1;
|
|
}
|
|
|
|
out:
|
|
free(sample.user_stack.data);
|
|
free(sample.user_regs.regs);
|
|
return err;
|
|
}
|
|
|
|
static int global_unwind_retval = -INT_MAX;
|
|
|
|
__attribute__ ((noinline))
|
|
static int compare(void *p1, void *p2)
|
|
{
|
|
/* Any possible value should be 'thread' */
|
|
struct thread *thread = *(struct thread **)p1;
|
|
|
|
if (global_unwind_retval == -INT_MAX) {
|
|
/* Call unwinder twice for both callchain orders. */
|
|
callchain_param.order = ORDER_CALLER;
|
|
|
|
global_unwind_retval = unwind_thread(thread);
|
|
if (!global_unwind_retval) {
|
|
callchain_param.order = ORDER_CALLEE;
|
|
global_unwind_retval = unwind_thread(thread);
|
|
}
|
|
}
|
|
|
|
return p1 - p2;
|
|
}
|
|
|
|
__attribute__ ((noinline))
|
|
static int krava_3(struct thread *thread)
|
|
{
|
|
struct thread *array[2] = {thread, thread};
|
|
void *fp = &bsearch;
|
|
/*
|
|
* make _bsearch a volatile function pointer to
|
|
* prevent potential optimization, which may expand
|
|
* bsearch and call compare directly from this function,
|
|
* instead of libc shared object.
|
|
*/
|
|
void *(*volatile _bsearch)(void *, void *, size_t,
|
|
size_t, int (*)(void *, void *));
|
|
|
|
_bsearch = fp;
|
|
_bsearch(array, &thread, 2, sizeof(struct thread **), compare);
|
|
return global_unwind_retval;
|
|
}
|
|
|
|
__attribute__ ((noinline))
|
|
static int krava_2(struct thread *thread)
|
|
{
|
|
return krava_3(thread);
|
|
}
|
|
|
|
__attribute__ ((noinline))
|
|
static int krava_1(struct thread *thread)
|
|
{
|
|
return krava_2(thread);
|
|
}
|
|
|
|
int test__dwarf_unwind(int subtest __maybe_unused)
|
|
{
|
|
struct machine *machine;
|
|
struct thread *thread;
|
|
int err = -1;
|
|
|
|
machine = machine__new_host();
|
|
if (!machine) {
|
|
pr_err("Could not get machine\n");
|
|
return -1;
|
|
}
|
|
|
|
if (machine__create_kernel_maps(machine)) {
|
|
pr_err("Failed to create kernel maps\n");
|
|
return -1;
|
|
}
|
|
|
|
callchain_param.record_mode = CALLCHAIN_DWARF;
|
|
|
|
if (init_live_machine(machine)) {
|
|
pr_err("Could not init machine\n");
|
|
goto out;
|
|
}
|
|
|
|
if (verbose > 1)
|
|
machine__fprintf(machine, stderr);
|
|
|
|
thread = machine__find_thread(machine, getpid(), getpid());
|
|
if (!thread) {
|
|
pr_err("Could not get thread\n");
|
|
goto out;
|
|
}
|
|
|
|
err = krava_1(thread);
|
|
thread__put(thread);
|
|
|
|
out:
|
|
machine__delete_threads(machine);
|
|
machine__delete(machine);
|
|
return err;
|
|
}
|