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Commit 3a68eef9 authored by Markus Metzger's avatar Markus Metzger Committed by Ingo Molnar
Browse files

x86, ds: add task tracing selftest 



Add selftests to cover per-task branch tracing.

Signed-off-by: default avatarMarkus Metzger <markus.t.metzger@intel.com>
Cc: roland@redhat.com
Cc: eranian@googlemail.com
Cc: oleg@redhat.com
Cc: juan.villacis@intel.com
Cc: ak@linux.jf.intel.com
LKML-Reference: <20090403144600.329346000@intel.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 01f6569e

arch/x86/kernel/ds_selftest.c

+71 −0
Original line number Diff line number Diff line
@@ -280,10 +280,51 @@ static int ds_selftest_bts_bad_release_noirq(int cpu, 
	return error ? 0 : -1;

}



static int ds_selftest_bts_bad_request_cpu(int cpu, void *buffer)

{

	struct bts_tracer *tracer;

	int error;



	/* Try to request cpu tracing while task tracing is active. */

	tracer = ds_request_bts_cpu(cpu, buffer, BUFFER_SIZE, NULL,

				    (size_t)-1, BTS_KERNEL);

	error = PTR_ERR(tracer);

	if (!IS_ERR(tracer)) {

		ds_release_bts(tracer);

		error = 0;

	}



	if (error != -EPERM)

		printk(KERN_CONT "cpu/task tracing overlap...");



	return error ? 0 : -1;

}



static int ds_selftest_bts_bad_request_task(void *buffer)

{

	struct bts_tracer *tracer;

	int error;



	/* Try to request cpu tracing while task tracing is active. */

	tracer = ds_request_bts_task(current, buffer, BUFFER_SIZE, NULL,

				    (size_t)-1, BTS_KERNEL);

	error = PTR_ERR(tracer);

	if (!IS_ERR(tracer)) {

		error = 0;

		ds_release_bts(tracer);

	}



	if (error != -EPERM)

		printk(KERN_CONT "task/cpu tracing overlap...");



	return error ? 0 : -1;

}



int ds_selftest_bts(void)

{

	struct ds_selftest_bts_conf conf;

	unsigned char buffer[BUFFER_SIZE];

	unsigned long irq;

	int cpu;



	printk(KERN_INFO "[ds] bts selftest...");
@@ -297,6 +338,8 @@ int ds_selftest_bts(void) 
			ds_request_bts_cpu(cpu, buffer, BUFFER_SIZE,

					   NULL, (size_t)-1, BTS_KERNEL);

		ds_selftest_bts_cpu(&conf);

		if (conf.error >= 0)

			conf.error = ds_selftest_bts_bad_request_task(buffer);

		ds_release_bts(conf.tracer);

		if (conf.error < 0)

			goto out;
@@ -315,12 +358,40 @@ int ds_selftest_bts(void) 
			if (conf.error < 0)

				conf.tracer = NULL;

		}

		if (conf.error >= 0)

			conf.error = ds_selftest_bts_bad_request_task(buffer);

		smp_call_function_single(cpu, ds_release_bts_noirq_wrap,

					 conf.tracer, 1);

		if (conf.error < 0)

			goto out;

	}



	conf.suspend = ds_suspend_bts_wrap;

	conf.resume = ds_resume_bts_wrap;

	conf.tracer =

		ds_request_bts_task(current, buffer, BUFFER_SIZE,

				    NULL, (size_t)-1, BTS_KERNEL);

	ds_selftest_bts_cpu(&conf);

	if (conf.error >= 0)

		conf.error = ds_selftest_bts_bad_request_cpu(0, buffer);

	ds_release_bts(conf.tracer);

	if (conf.error < 0)

		goto out;



	conf.suspend = ds_suspend_bts_noirq;

	conf.resume = ds_resume_bts_noirq;

	conf.tracer =

		ds_request_bts_task(current, buffer, BUFFER_SIZE,

				   NULL, (size_t)-1, BTS_KERNEL);

	local_irq_save(irq);

	ds_selftest_bts_cpu(&conf);

	if (conf.error >= 0)

		conf.error = ds_selftest_bts_bad_request_cpu(0, buffer);

	ds_release_bts_noirq(conf.tracer);

	local_irq_restore(irq);

	if (conf.error < 0)

		goto out;



	conf.error = 0;

 out:

	put_online_cpus();