 d75e6097ef
			
		
	
	
	d75e6097ef
	
	
	
		
			
			Forcing the code to always search thread by pid/tid pair. The PID value will be needed in future to determine the process thread leader for map groups sharing. Signed-off-by: Jiri Olsa <jolsa@redhat.com> Acked-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: David Ahern <dsahern@gmail.com> Cc: Don Zickus <dzickus@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1394805606-25883-3-git-send-email-jolsa@redhat.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
		
			
				
	
	
		
			144 lines
		
	
	
	
		
			3 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			144 lines
		
	
	
	
		
			3 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| #include <linux/compiler.h>
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| #include <sys/types.h>
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| #include <unistd.h>
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| #include "tests.h"
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| #include "debug.h"
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| #include "machine.h"
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| #include "event.h"
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| #include "unwind.h"
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| #include "perf_regs.h"
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| #include "map.h"
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| #include "thread.h"
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| 
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| static int mmap_handler(struct perf_tool *tool __maybe_unused,
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| 			union perf_event *event,
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| 			struct perf_sample *sample __maybe_unused,
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| 			struct machine *machine)
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| {
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| 	return machine__process_mmap_event(machine, event, NULL);
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| }
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| 
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| static int init_live_machine(struct machine *machine)
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| {
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| 	union perf_event event;
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| 	pid_t pid = getpid();
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| 
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| 	return perf_event__synthesize_mmap_events(NULL, &event, pid, pid,
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| 						  mmap_handler, machine, true);
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| }
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| 
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| #define MAX_STACK 6
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| 
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| static int unwind_entry(struct unwind_entry *entry, void *arg)
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| {
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| 	unsigned long *cnt = (unsigned long *) arg;
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| 	char *symbol = entry->sym ? entry->sym->name : NULL;
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| 	static const char *funcs[MAX_STACK] = {
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| 		"test__arch_unwind_sample",
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| 		"unwind_thread",
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| 		"krava_3",
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| 		"krava_2",
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| 		"krava_1",
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| 		"test__dwarf_unwind"
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| 	};
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| 
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| 	if (*cnt >= MAX_STACK) {
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| 		pr_debug("failed: crossed the max stack value %d\n", MAX_STACK);
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| 		return -1;
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| 	}
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| 
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| 	if (!symbol) {
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| 		pr_debug("failed: got unresolved address 0x%" PRIx64 "\n",
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| 			 entry->ip);
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| 		return -1;
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| 	}
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| 
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| 	pr_debug("got: %s 0x%" PRIx64 "\n", symbol, entry->ip);
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| 	return strcmp((const char *) symbol, funcs[(*cnt)++]);
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| }
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| 
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| __attribute__ ((noinline))
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| static int unwind_thread(struct thread *thread, struct machine *machine)
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| {
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| 	struct perf_sample sample;
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| 	unsigned long cnt = 0;
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| 	int err = -1;
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| 
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| 	memset(&sample, 0, sizeof(sample));
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| 
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| 	if (test__arch_unwind_sample(&sample, thread)) {
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| 		pr_debug("failed to get unwind sample\n");
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| 		goto out;
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| 	}
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| 
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| 	err = unwind__get_entries(unwind_entry, &cnt, machine, thread,
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| 				  &sample, MAX_STACK);
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| 	if (err)
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| 		pr_debug("unwind failed\n");
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| 	else if (cnt != MAX_STACK) {
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| 		pr_debug("got wrong number of stack entries %lu != %d\n",
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| 			 cnt, MAX_STACK);
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| 		err = -1;
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| 	}
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| 
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|  out:
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| 	free(sample.user_stack.data);
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| 	free(sample.user_regs.regs);
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| 	return err;
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| }
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| 
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| __attribute__ ((noinline))
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| static int krava_3(struct thread *thread, struct machine *machine)
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| {
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| 	return unwind_thread(thread, machine);
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| }
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| 
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| __attribute__ ((noinline))
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| static int krava_2(struct thread *thread, struct machine *machine)
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| {
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| 	return krava_3(thread, machine);
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| }
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| 
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| __attribute__ ((noinline))
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| static int krava_1(struct thread *thread, struct machine *machine)
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| {
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| 	return krava_2(thread, machine);
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| }
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| 
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| int test__dwarf_unwind(void)
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| {
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| 	struct machines machines;
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| 	struct machine *machine;
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| 	struct thread *thread;
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| 	int err = -1;
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| 
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| 	machines__init(&machines);
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| 
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| 	machine = machines__find(&machines, HOST_KERNEL_ID);
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| 	if (!machine) {
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| 		pr_err("Could not get machine\n");
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| 		return -1;
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| 	}
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| 
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| 	if (init_live_machine(machine)) {
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| 		pr_err("Could not init machine\n");
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| 		goto out;
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| 	}
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| 
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| 	if (verbose > 1)
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| 		machine__fprintf(machine, stderr);
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| 
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| 	thread = machine__find_thread(machine, getpid(), getpid());
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| 	if (!thread) {
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| 		pr_err("Could not get thread\n");
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| 		goto out;
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| 	}
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| 
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| 	err = krava_1(thread, machine);
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| 
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|  out:
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| 	machine__delete_threads(machine);
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| 	machine__exit(machine);
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| 	machines__exit(&machines);
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| 	return err;
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| }
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