Commit f8619c30 authored by Paul E. McKenney's avatar Paul E. McKenney
Browse files

locktorture: Add long_hold to adjust lock-hold delays 



This commit adds a long_hold module parameter to allow testing diagnostics
for excessive lock-hold times.  Also adjust torture_param() invocations
for longer line length while in the area.

Signed-off-by: default avatarPaul E. McKenney <paulmck@kernel.org>
Reviewed-by: default avatarJoel Fernandes (Google) <joel@joelfernandes.org>
parent ac9a7868

kernel/locking/locktorture.c

+22 −29
Original line number Diff line number Diff line
@@ -33,24 +33,19 @@ 
MODULE_LICENSE("GPL");

MODULE_AUTHOR("Paul E. McKenney <paulmck@linux.ibm.com>");



torture_param(int, nwriters_stress, -1,

	     "Number of write-locking stress-test threads");

torture_param(int, nreaders_stress, -1,

	     "Number of read-locking stress-test threads");

torture_param(int, nwriters_stress, -1, "Number of write-locking stress-test threads");

torture_param(int, nreaders_stress, -1, "Number of read-locking stress-test threads");

torture_param(int, long_hold, 100, "Do occasional long hold of lock (ms), 0=disable");

torture_param(int, onoff_holdoff, 0, "Time after boot before CPU hotplugs (s)");

torture_param(int, onoff_interval, 0,

	     "Time between CPU hotplugs (s), 0=disable");

torture_param(int, shuffle_interval, 3,

	     "Number of jiffies between shuffles, 0=disable");

torture_param(int, onoff_interval, 0, "Time between CPU hotplugs (s), 0=disable");

torture_param(int, shuffle_interval, 3, "Number of jiffies between shuffles, 0=disable");

torture_param(int, shutdown_secs, 0, "Shutdown time (j), <= zero to disable.");

torture_param(int, stat_interval, 60,

	     "Number of seconds between stats printk()s");

torture_param(int, stat_interval, 60, "Number of seconds between stats printk()s");

torture_param(int, stutter, 5, "Number of jiffies to run/halt test, 0=disable");

torture_param(int, rt_boost, 2,

		   "Do periodic rt-boost. 0=Disable, 1=Only for rt_mutex, 2=For all lock types.");

torture_param(int, rt_boost_factor, 50, "A factor determining how often rt-boost happens.");

torture_param(int, verbose, 1,

	     "Enable verbose debugging printk()s");

torture_param(int, verbose, 1, "Enable verbose debugging printk()s");

torture_param(int, nested_locks, 0, "Number of nested locks (max = 8)");

/* Going much higher trips "BUG: MAX_LOCKDEP_CHAIN_HLOCKS too low!" errors */

#define MAX_NESTED_LOCKS 8
@@ -120,7 +115,7 @@ static int torture_lock_busted_write_lock(int tid __maybe_unused) 


static void torture_lock_busted_write_delay(struct torture_random_state *trsp)

{

	const unsigned long longdelay_ms = 100;

	const unsigned long longdelay_ms = long_hold ? long_hold : ULONG_MAX;



	/* We want a long delay occasionally to force massive contention.  */

	if (!(torture_random(trsp) %
@@ -198,16 +193,18 @@ __acquires(torture_spinlock) 
static void torture_spin_lock_write_delay(struct torture_random_state *trsp)

{

	const unsigned long shortdelay_us = 2;

	const unsigned long longdelay_ms = 100;

	const unsigned long longdelay_ms = long_hold ? long_hold : ULONG_MAX;

	unsigned long j;



	/* We want a short delay mostly to emulate likely code, and

	 * we want a long delay occasionally to force massive contention.

	 */

	if (!(torture_random(trsp) %

	      (cxt.nrealwriters_stress * 2000 * longdelay_ms)))

	if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 2000 * longdelay_ms))) {

		j = jiffies;

		mdelay(longdelay_ms);

	if (!(torture_random(trsp) %

	      (cxt.nrealwriters_stress * 2 * shortdelay_us)))

		pr_alert("%s: delay = %lu jiffies.\n", __func__, jiffies - j);

	}

	if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 200 * shortdelay_us)))

		udelay(shortdelay_us);

	if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 20000)))

		torture_preempt_schedule();  /* Allow test to be preempted. */
@@ -322,7 +319,7 @@ __acquires(torture_rwlock) 
static void torture_rwlock_write_delay(struct torture_random_state *trsp)

{

	const unsigned long shortdelay_us = 2;

	const unsigned long longdelay_ms = 100;

	const unsigned long longdelay_ms = long_hold ? long_hold : ULONG_MAX;



	/* We want a short delay mostly to emulate likely code, and

	 * we want a long delay occasionally to force massive contention.
@@ -455,14 +452,12 @@ __acquires(torture_mutex) 


static void torture_mutex_delay(struct torture_random_state *trsp)

{

	const unsigned long longdelay_ms = 100;

	const unsigned long longdelay_ms = long_hold ? long_hold : ULONG_MAX;



	/* We want a long delay occasionally to force massive contention.  */

	if (!(torture_random(trsp) %

	      (cxt.nrealwriters_stress * 2000 * longdelay_ms)))

		mdelay(longdelay_ms * 5);

	else

		mdelay(longdelay_ms / 5);

	if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 20000)))

		torture_preempt_schedule();  /* Allow test to be preempted. */

}
@@ -630,7 +625,7 @@ __acquires(torture_rtmutex) 
static void torture_rtmutex_delay(struct torture_random_state *trsp)

{

	const unsigned long shortdelay_us = 2;

	const unsigned long longdelay_ms = 100;

	const unsigned long longdelay_ms = long_hold ? long_hold : ULONG_MAX;



	/*

	 * We want a short delay mostly to emulate likely code, and
@@ -640,7 +635,7 @@ static void torture_rtmutex_delay(struct torture_random_state *trsp) 
	      (cxt.nrealwriters_stress * 2000 * longdelay_ms)))

		mdelay(longdelay_ms);

	if (!(torture_random(trsp) %

	      (cxt.nrealwriters_stress * 2 * shortdelay_us)))

	      (cxt.nrealwriters_stress * 200 * shortdelay_us)))

		udelay(shortdelay_us);

	if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 20000)))

		torture_preempt_schedule();  /* Allow test to be preempted. */
@@ -695,14 +690,12 @@ __acquires(torture_rwsem) 


static void torture_rwsem_write_delay(struct torture_random_state *trsp)

{

	const unsigned long longdelay_ms = 100;

	const unsigned long longdelay_ms = long_hold ? long_hold : ULONG_MAX;



	/* We want a long delay occasionally to force massive contention.  */

	if (!(torture_random(trsp) %

	      (cxt.nrealwriters_stress * 2000 * longdelay_ms)))

		mdelay(longdelay_ms * 10);

	else

		mdelay(longdelay_ms / 10);

	if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 20000)))

		torture_preempt_schedule();  /* Allow test to be preempted. */

}
@@ -848,8 +841,8 @@ static int lock_torture_writer(void *arg) 


			lwsp->n_lock_acquired++;

		}

		cxt.cur_ops->write_delay(&rand);

		if (!skip_main_lock) {

			cxt.cur_ops->write_delay(&rand);

			lock_is_write_held = false;

			WRITE_ONCE(last_lock_release, jiffies);

			cxt.cur_ops->writeunlock(tid);