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-rw-r--r--kernel/rcu/rcutorture.c356
1 files changed, 298 insertions, 58 deletions
diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
index 70ec0f21abc3..7a893d51d02b 100644
--- a/kernel/rcu/rcutorture.c
+++ b/kernel/rcu/rcutorture.c
@@ -55,22 +55,24 @@ MODULE_DESCRIPTION("Read-Copy Update module-based torture test facility");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Paul E. McKenney <paulmck@linux.ibm.com> and Josh Triplett <josh@joshtriplett.org>");
-/* Bits for ->extendables field, extendables param, and related definitions. */
-#define RCUTORTURE_RDR_SHIFT_1 8 /* Put SRCU index in upper bits. */
-#define RCUTORTURE_RDR_MASK_1 (0xff << RCUTORTURE_RDR_SHIFT_1)
-#define RCUTORTURE_RDR_SHIFT_2 16 /* Put SRCU index in upper bits. */
-#define RCUTORTURE_RDR_MASK_2 (0xff << RCUTORTURE_RDR_SHIFT_2)
-#define RCUTORTURE_RDR_BH 0x01 /* Extend readers by disabling bh. */
-#define RCUTORTURE_RDR_IRQ 0x02 /* ... disabling interrupts. */
-#define RCUTORTURE_RDR_PREEMPT 0x04 /* ... disabling preemption. */
-#define RCUTORTURE_RDR_RBH 0x08 /* ... rcu_read_lock_bh(). */
-#define RCUTORTURE_RDR_SCHED 0x10 /* ... rcu_read_lock_sched(). */
-#define RCUTORTURE_RDR_RCU_1 0x20 /* ... entering another RCU reader. */
-#define RCUTORTURE_RDR_RCU_2 0x40 /* ... entering another RCU reader. */
-#define RCUTORTURE_RDR_NBITS 7 /* Number of bits defined above. */
-#define RCUTORTURE_MAX_EXTEND \
+// Bits for ->extendables field, extendables param, and related definitions.
+#define RCUTORTURE_RDR_SHIFT_1 8 // Put SRCU index in upper bits.
+#define RCUTORTURE_RDR_MASK_1 (0xff << RCUTORTURE_RDR_SHIFT_1)
+#define RCUTORTURE_RDR_SHIFT_2 16 // Put SRCU index in upper bits.
+#define RCUTORTURE_RDR_MASK_2 (0xff << RCUTORTURE_RDR_SHIFT_2)
+#define RCUTORTURE_RDR_BH 0x01 // Extend readers by disabling bh.
+#define RCUTORTURE_RDR_IRQ 0x02 // ... disabling interrupts.
+#define RCUTORTURE_RDR_PREEMPT 0x04 // ... disabling preemption.
+#define RCUTORTURE_RDR_RBH 0x08 // ... rcu_read_lock_bh().
+#define RCUTORTURE_RDR_SCHED 0x10 // ... rcu_read_lock_sched().
+#define RCUTORTURE_RDR_RCU_1 0x20 // ... entering another RCU reader.
+#define RCUTORTURE_RDR_RCU_2 0x40 // ... entering another RCU reader.
+#define RCUTORTURE_RDR_UPDOWN 0x80 // ... up-read from task, down-read from timer.
+ // Note: Manual start, automatic end.
+#define RCUTORTURE_RDR_NBITS 8 // Number of bits defined above.
+#define RCUTORTURE_MAX_EXTEND \
(RCUTORTURE_RDR_BH | RCUTORTURE_RDR_IRQ | RCUTORTURE_RDR_PREEMPT | \
- RCUTORTURE_RDR_RBH | RCUTORTURE_RDR_SCHED)
+ RCUTORTURE_RDR_RBH | RCUTORTURE_RDR_SCHED) // Intentionally omit RCUTORTURE_RDR_UPDOWN.
#define RCUTORTURE_RDR_ALLBITS \
(RCUTORTURE_MAX_EXTEND | RCUTORTURE_RDR_RCU_1 | RCUTORTURE_RDR_RCU_2 | \
RCUTORTURE_RDR_MASK_1 | RCUTORTURE_RDR_MASK_2)
@@ -110,6 +112,7 @@ torture_param(bool, gp_sync, false, "Use synchronous GP wait primitives");
torture_param(int, irqreader, 1, "Allow RCU readers from irq handlers");
torture_param(int, leakpointer, 0, "Leak pointer dereferences from readers");
torture_param(int, n_barrier_cbs, 0, "# of callbacks/kthreads for barrier testing");
+torture_param(int, n_up_down, 32, "# of concurrent up/down hrtimer-based RCU readers");
torture_param(int, nfakewriters, 4, "Number of RCU fake writer threads");
torture_param(int, nreaders, -1, "Number of RCU reader threads");
torture_param(int, object_debug, 0, "Enable debug-object double call_rcu() testing");
@@ -156,6 +159,7 @@ static int nrealfakewriters;
static struct task_struct *writer_task;
static struct task_struct **fakewriter_tasks;
static struct task_struct **reader_tasks;
+static struct task_struct *updown_task;
static struct task_struct **nocb_tasks;
static struct task_struct *stats_task;
static struct task_struct *fqs_task;
@@ -378,6 +382,8 @@ struct rcu_torture_ops {
void (*readunlock)(int idx);
int (*readlock_held)(void); // lockdep.
int (*readlock_nesting)(void); // actual nesting, if available, -1 if not.
+ int (*down_read)(void);
+ void (*up_read)(int idx);
unsigned long (*get_gp_seq)(void);
unsigned long (*gp_diff)(unsigned long new, unsigned long old);
void (*deferred_free)(struct rcu_torture *p);
@@ -427,6 +433,7 @@ struct rcu_torture_ops {
int no_pi_lock;
int debug_objects;
int start_poll_irqsoff;
+ int have_up_down;
const char *name;
};
@@ -464,7 +471,7 @@ rcu_read_delay(struct torture_random_state *rrsp, struct rt_read_seg *rtrsp)
!(torture_random(rrsp) % (nrealreaders * 2000 * longdelay_ms))) {
started = cur_ops->get_gp_seq();
ts = rcu_trace_clock_local();
- if (preempt_count() & (SOFTIRQ_MASK | HARDIRQ_MASK))
+ if ((preempt_count() & HARDIRQ_MASK) || softirq_count())
longdelay_ms = 5; /* Avoid triggering BH limits. */
mdelay(longdelay_ms);
rtrsp->rt_delay_ms = longdelay_ms;
@@ -711,11 +718,6 @@ static int srcu_torture_read_lock(void)
WARN_ON_ONCE(idx & ~0x1);
ret += idx << 1;
}
- if (reader_flavor & SRCU_READ_FLAVOR_LITE) {
- idx = srcu_read_lock_lite(srcu_ctlp);
- WARN_ON_ONCE(idx & ~0x1);
- ret += idx << 2;
- }
if (reader_flavor & SRCU_READ_FLAVOR_FAST) {
scp = srcu_read_lock_fast(srcu_ctlp);
idx = __srcu_ptr_to_ctr(srcu_ctlp, scp);
@@ -749,8 +751,6 @@ static void srcu_torture_read_unlock(int idx)
WARN_ON_ONCE((reader_flavor && (idx & ~reader_flavor)) || (!reader_flavor && (idx & ~0x1)));
if (reader_flavor & SRCU_READ_FLAVOR_FAST)
srcu_read_unlock_fast(srcu_ctlp, __srcu_ctr_to_ptr(srcu_ctlp, (idx & 0x8) >> 3));
- if (reader_flavor & SRCU_READ_FLAVOR_LITE)
- srcu_read_unlock_lite(srcu_ctlp, (idx & 0x4) >> 2);
if (reader_flavor & SRCU_READ_FLAVOR_NMI)
srcu_read_unlock_nmisafe(srcu_ctlp, (idx & 0x2) >> 1);
if ((reader_flavor & SRCU_READ_FLAVOR_NORMAL) || !(reader_flavor & SRCU_READ_FLAVOR_ALL))
@@ -762,6 +762,50 @@ static int torture_srcu_read_lock_held(void)
return srcu_read_lock_held(srcu_ctlp);
}
+static bool srcu_torture_have_up_down(void)
+{
+ int rf = reader_flavor;
+
+ if (!rf)
+ rf = SRCU_READ_FLAVOR_NORMAL;
+ return !!(cur_ops->have_up_down & rf);
+}
+
+static int srcu_torture_down_read(void)
+{
+ int idx;
+ struct srcu_ctr __percpu *scp;
+
+ WARN_ON_ONCE(reader_flavor & ~SRCU_READ_FLAVOR_ALL);
+ WARN_ON_ONCE(reader_flavor & (reader_flavor - 1));
+
+ if ((reader_flavor & SRCU_READ_FLAVOR_NORMAL) || !(reader_flavor & SRCU_READ_FLAVOR_ALL)) {
+ idx = srcu_down_read(srcu_ctlp);
+ WARN_ON_ONCE(idx & ~0x1);
+ return idx;
+ }
+ if (reader_flavor & SRCU_READ_FLAVOR_FAST) {
+ scp = srcu_down_read_fast(srcu_ctlp);
+ idx = __srcu_ptr_to_ctr(srcu_ctlp, scp);
+ WARN_ON_ONCE(idx & ~0x1);
+ return idx << 3;
+ }
+ WARN_ON_ONCE(1);
+ return 0;
+}
+
+static void srcu_torture_up_read(int idx)
+{
+ WARN_ON_ONCE((reader_flavor && (idx & ~reader_flavor)) || (!reader_flavor && (idx & ~0x1)));
+ if (reader_flavor & SRCU_READ_FLAVOR_FAST)
+ srcu_up_read_fast(srcu_ctlp, __srcu_ctr_to_ptr(srcu_ctlp, (idx & 0x8) >> 3));
+ else if ((reader_flavor & SRCU_READ_FLAVOR_NORMAL) ||
+ !(reader_flavor & SRCU_READ_FLAVOR_ALL))
+ srcu_up_read(srcu_ctlp, idx & 0x1);
+ else
+ WARN_ON_ONCE(1);
+}
+
static unsigned long srcu_torture_completed(void)
{
return srcu_batches_completed(srcu_ctlp);
@@ -819,6 +863,8 @@ static struct rcu_torture_ops srcu_ops = {
.readlock = srcu_torture_read_lock,
.read_delay = srcu_read_delay,
.readunlock = srcu_torture_read_unlock,
+ .down_read = srcu_torture_down_read,
+ .up_read = srcu_torture_up_read,
.readlock_held = torture_srcu_read_lock_held,
.get_gp_seq = srcu_torture_completed,
.gp_diff = rcu_seq_diff,
@@ -839,6 +885,8 @@ static struct rcu_torture_ops srcu_ops = {
.irq_capable = 1,
.no_pi_lock = IS_ENABLED(CONFIG_TINY_SRCU),
.debug_objects = 1,
+ .have_up_down = IS_ENABLED(CONFIG_TINY_SRCU)
+ ? 0 : SRCU_READ_FLAVOR_NORMAL | SRCU_READ_FLAVOR_FAST,
.name = "srcu"
};
@@ -864,6 +912,8 @@ static struct rcu_torture_ops srcud_ops = {
.read_delay = srcu_read_delay,
.readunlock = srcu_torture_read_unlock,
.readlock_held = torture_srcu_read_lock_held,
+ .down_read = srcu_torture_down_read,
+ .up_read = srcu_torture_up_read,
.get_gp_seq = srcu_torture_completed,
.gp_diff = rcu_seq_diff,
.deferred_free = srcu_torture_deferred_free,
@@ -883,6 +933,8 @@ static struct rcu_torture_ops srcud_ops = {
.irq_capable = 1,
.no_pi_lock = IS_ENABLED(CONFIG_TINY_SRCU),
.debug_objects = 1,
+ .have_up_down = IS_ENABLED(CONFIG_TINY_SRCU)
+ ? 0 : SRCU_READ_FLAVOR_NORMAL | SRCU_READ_FLAVOR_FAST,
.name = "srcud"
};
@@ -910,7 +962,8 @@ static struct rcu_torture_ops busted_srcud_ops = {
/*
* Definitions for trivial CONFIG_PREEMPT=n-only torture testing.
- * This implementation does not necessarily work well with CPU hotplug.
+ * This implementation does not work well with CPU hotplug nor
+ * with rcutorture's shuffling.
*/
static void synchronize_rcu_trivial(void)
@@ -923,6 +976,16 @@ static void synchronize_rcu_trivial(void)
}
}
+static void rcu_sync_torture_init_trivial(void)
+{
+ rcu_sync_torture_init();
+ // if (onoff_interval || shuffle_interval) {
+ if (WARN_ONCE(onoff_interval || shuffle_interval, "%s: Non-zero onoff_interval (%d) or shuffle_interval (%d) breaks trivial RCU, resetting to zero", __func__, onoff_interval, shuffle_interval)) {
+ onoff_interval = 0;
+ shuffle_interval = 0;
+ }
+}
+
static int rcu_torture_read_lock_trivial(void)
{
preempt_disable();
@@ -936,7 +999,7 @@ static void rcu_torture_read_unlock_trivial(int idx)
static struct rcu_torture_ops trivial_ops = {
.ttype = RCU_TRIVIAL_FLAVOR,
- .init = rcu_sync_torture_init,
+ .init = rcu_sync_torture_init_trivial,
.readlock = rcu_torture_read_lock_trivial,
.read_delay = rcu_read_delay, /* just reuse rcu's version. */
.readunlock = rcu_torture_read_unlock_trivial,
@@ -1722,6 +1785,7 @@ rcu_torture_writer(void *arg)
cur_ops->gp_kthread_dbg();
WARN(1, "%s: rtort_pipe_count: %d\n", __func__, rcu_tortures[i].rtort_pipe_count);
rcu_ftrace_dump(DUMP_ALL);
+ break;
}
if (stutter_waited)
sched_set_normal(current, oldnice);
@@ -1915,14 +1979,14 @@ static void rcu_torture_reader_do_mbchk(long myid, struct rcu_torture *rtp,
// Verify the specified RCUTORTURE_RDR* state.
#define ROEC_ARGS "%s %s: Current %#x To add %#x To remove %#x preempt_count() %#x\n", __func__, s, curstate, new, old, preempt_count()
-static void rcutorture_one_extend_check(char *s, int curstate, int new, int old, bool insoftirq)
+static void rcutorture_one_extend_check(char *s, int curstate, int new, int old)
{
int mask;
- if (!IS_ENABLED(CONFIG_RCU_TORTURE_TEST_CHK_RDR_STATE))
+ if (!IS_ENABLED(CONFIG_RCU_TORTURE_TEST_CHK_RDR_STATE) || in_nmi())
return;
- WARN_ONCE(!(curstate & RCUTORTURE_RDR_IRQ) && irqs_disabled(), ROEC_ARGS);
+ WARN_ONCE(!(curstate & RCUTORTURE_RDR_IRQ) && irqs_disabled() && !in_hardirq(), ROEC_ARGS);
WARN_ONCE((curstate & RCUTORTURE_RDR_IRQ) && !irqs_disabled(), ROEC_ARGS);
// If CONFIG_PREEMPT_COUNT=n, further checks are unreliable.
@@ -1930,21 +1994,21 @@ static void rcutorture_one_extend_check(char *s, int curstate, int new, int old,
return;
WARN_ONCE((curstate & (RCUTORTURE_RDR_BH | RCUTORTURE_RDR_RBH)) &&
- !(preempt_count() & SOFTIRQ_MASK), ROEC_ARGS);
+ !softirq_count(), ROEC_ARGS);
WARN_ONCE((curstate & (RCUTORTURE_RDR_PREEMPT | RCUTORTURE_RDR_SCHED)) &&
!(preempt_count() & PREEMPT_MASK), ROEC_ARGS);
WARN_ONCE(cur_ops->readlock_nesting &&
(curstate & (RCUTORTURE_RDR_RCU_1 | RCUTORTURE_RDR_RCU_2)) &&
cur_ops->readlock_nesting() == 0, ROEC_ARGS);
- // Timer handlers have all sorts of stuff disabled, so ignore
+ // Interrupt handlers have all sorts of stuff disabled, so ignore
// unintended disabling.
- if (insoftirq)
+ if (in_serving_softirq() || in_hardirq())
return;
WARN_ONCE(cur_ops->extendables &&
!(curstate & (RCUTORTURE_RDR_BH | RCUTORTURE_RDR_RBH)) &&
- (preempt_count() & SOFTIRQ_MASK), ROEC_ARGS);
+ softirq_count(), ROEC_ARGS);
/*
* non-preemptible RCU in a preemptible kernel uses preempt_disable()
@@ -1965,6 +2029,9 @@ static void rcutorture_one_extend_check(char *s, int curstate, int new, int old,
if (!IS_ENABLED(CONFIG_PREEMPT_RCU))
mask |= RCUTORTURE_RDR_PREEMPT | RCUTORTURE_RDR_SCHED;
+ if (IS_ENABLED(CONFIG_PREEMPT_RT) && softirq_count())
+ mask |= RCUTORTURE_RDR_BH | RCUTORTURE_RDR_RBH;
+
WARN_ONCE(cur_ops->readlock_nesting && !(curstate & mask) &&
cur_ops->readlock_nesting() > 0, ROEC_ARGS);
}
@@ -1978,8 +2045,7 @@ static void rcutorture_one_extend_check(char *s, int curstate, int new, int old,
* beginning or end of the critical section and if there was actually a
* change, do a ->read_delay().
*/
-static void rcutorture_one_extend(int *readstate, int newstate, bool insoftirq,
- struct torture_random_state *trsp,
+static void rcutorture_one_extend(int *readstate, int newstate, struct torture_random_state *trsp,
struct rt_read_seg *rtrsp)
{
bool first;
@@ -1993,8 +2059,8 @@ static void rcutorture_one_extend(int *readstate, int newstate, bool insoftirq,
first = idxold1 == 0;
WARN_ON_ONCE(idxold2 < 0);
- WARN_ON_ONCE(idxold2 & ~RCUTORTURE_RDR_ALLBITS);
- rcutorture_one_extend_check("before change", idxold1, statesnew, statesold, insoftirq);
+ WARN_ON_ONCE(idxold2 & ~(RCUTORTURE_RDR_ALLBITS | RCUTORTURE_RDR_UPDOWN));
+ rcutorture_one_extend_check("before change", idxold1, statesnew, statesold);
rtrsp->rt_readstate = newstate;
/* First, put new protection in place to avoid critical-section gap. */
@@ -2014,8 +2080,7 @@ static void rcutorture_one_extend(int *readstate, int newstate, bool insoftirq,
idxnew2 = (cur_ops->readlock() << RCUTORTURE_RDR_SHIFT_2) & RCUTORTURE_RDR_MASK_2;
// Complain unless both the old and the new protection is in place.
- rcutorture_one_extend_check("during change",
- idxold1 | statesnew, statesnew, statesold, insoftirq);
+ rcutorture_one_extend_check("during change", idxold1 | statesnew, statesnew, statesold);
// Sample CPU under both sets of protections to reduce confusion.
if (IS_ENABLED(CONFIG_RCU_TORTURE_TEST_LOG_CPU)) {
@@ -2069,6 +2134,11 @@ static void rcutorture_one_extend(int *readstate, int newstate, bool insoftirq,
if (lockit)
raw_spin_unlock_irqrestore(&current->pi_lock, flags);
}
+ if (statesold & RCUTORTURE_RDR_UPDOWN) {
+ cur_ops->up_read((idxold1 & RCUTORTURE_RDR_MASK_1) >> RCUTORTURE_RDR_SHIFT_1);
+ WARN_ON_ONCE(idxnew1 != -1);
+ idxold1 = 0;
+ }
/* Delay if neither beginning nor end and there was a change. */
if ((statesnew || statesold) && *readstate && newstate)
@@ -2085,7 +2155,7 @@ static void rcutorture_one_extend(int *readstate, int newstate, bool insoftirq,
WARN_ON_ONCE(*readstate < 0);
if (WARN_ON_ONCE(*readstate & ~RCUTORTURE_RDR_ALLBITS))
pr_info("Unexpected readstate value of %#x\n", *readstate);
- rcutorture_one_extend_check("after change", *readstate, statesnew, statesold, insoftirq);
+ rcutorture_one_extend_check("after change", *readstate, statesnew, statesold);
}
/* Return the biggest extendables mask given current RCU and boot parameters. */
@@ -2152,8 +2222,7 @@ rcutorture_extend_mask(int oldmask, struct torture_random_state *trsp)
* critical section.
*/
static struct rt_read_seg *
-rcutorture_loop_extend(int *readstate, bool insoftirq, struct torture_random_state *trsp,
- struct rt_read_seg *rtrsp)
+rcutorture_loop_extend(int *readstate, struct torture_random_state *trsp, struct rt_read_seg *rtrsp)
{
int i;
int j;
@@ -2167,7 +2236,8 @@ rcutorture_loop_extend(int *readstate, bool insoftirq, struct torture_random_sta
i = ((i | (i >> 3)) & RCUTORTURE_RDR_MAX_LOOPS) + 1;
for (j = 0; j < i; j++) {
mask = rcutorture_extend_mask(*readstate, trsp);
- rcutorture_one_extend(readstate, mask, insoftirq, trsp, &rtrsp[j]);
+ WARN_ON_ONCE(mask & RCUTORTURE_RDR_UPDOWN);
+ rcutorture_one_extend(readstate, mask, trsp, &rtrsp[j]);
}
return &rtrsp[j];
}
@@ -2209,10 +2279,11 @@ static bool rcu_torture_one_read_start(struct rcu_torture_one_read_state *rtorsp
rtorsp->started = cur_ops->get_gp_seq();
rtorsp->ts = rcu_trace_clock_local();
rtorsp->p = rcu_dereference_check(rcu_torture_current,
- !cur_ops->readlock_held || cur_ops->readlock_held());
+ !cur_ops->readlock_held || cur_ops->readlock_held() ||
+ (rtorsp->readstate & RCUTORTURE_RDR_UPDOWN));
if (rtorsp->p == NULL) {
/* Wait for rcu_torture_writer to get underway */
- rcutorture_one_extend(&rtorsp->readstate, 0, myid < 0, trsp, rtorsp->rtrsp);
+ rcutorture_one_extend(&rtorsp->readstate, 0, trsp, rtorsp->rtrsp);
return false;
}
if (rtorsp->p->rtort_mbtest == 0)
@@ -2226,7 +2297,7 @@ static bool rcu_torture_one_read_start(struct rcu_torture_one_read_state *rtorsp
* critical sections and check for errors.
*/
static void rcu_torture_one_read_end(struct rcu_torture_one_read_state *rtorsp,
- struct torture_random_state *trsp, long myid)
+ struct torture_random_state *trsp)
{
int i;
unsigned long completed;
@@ -2273,7 +2344,7 @@ static void rcu_torture_one_read_end(struct rcu_torture_one_read_state *rtorsp,
}
if (cur_ops->reader_blocked)
preempted = cur_ops->reader_blocked();
- rcutorture_one_extend(&rtorsp->readstate, 0, myid < 0, trsp, rtorsp->rtrsp);
+ rcutorture_one_extend(&rtorsp->readstate, 0, trsp, rtorsp->rtrsp);
WARN_ON_ONCE(rtorsp->readstate);
// This next splat is expected behavior if leakpointer, especially
// for CONFIG_RCU_STRICT_GRACE_PERIOD=y kernels.
@@ -2302,13 +2373,14 @@ static bool rcu_torture_one_read(struct torture_random_state *trsp, long myid)
WARN_ON_ONCE(!rcu_is_watching());
init_rcu_torture_one_read_state(&rtors, trsp);
newstate = rcutorture_extend_mask(rtors.readstate, trsp);
- rcutorture_one_extend(&rtors.readstate, newstate, myid < 0, trsp, rtors.rtrsp++);
+ WARN_ON_ONCE(newstate & RCUTORTURE_RDR_UPDOWN);
+ rcutorture_one_extend(&rtors.readstate, newstate, trsp, rtors.rtrsp++);
if (!rcu_torture_one_read_start(&rtors, trsp, myid)) {
- rcutorture_one_extend(&rtors.readstate, 0, myid < 0, trsp, rtors.rtrsp);
+ rcutorture_one_extend(&rtors.readstate, 0, trsp, rtors.rtrsp);
return false;
}
- rtors.rtrsp = rcutorture_loop_extend(&rtors.readstate, myid < 0, trsp, rtors.rtrsp);
- rcu_torture_one_read_end(&rtors, trsp, myid);
+ rtors.rtrsp = rcutorture_loop_extend(&rtors.readstate, trsp, rtors.rtrsp);
+ rcu_torture_one_read_end(&rtors, trsp);
return true;
}
@@ -2378,6 +2450,152 @@ rcu_torture_reader(void *arg)
return 0;
}
+struct rcu_torture_one_read_state_updown {
+ struct hrtimer rtorsu_hrt;
+ bool rtorsu_inuse;
+ ktime_t rtorsu_kt;
+ int rtorsu_cpu;
+ unsigned long rtorsu_j;
+ unsigned long rtorsu_ndowns;
+ unsigned long rtorsu_nups;
+ unsigned long rtorsu_nmigrates;
+ struct torture_random_state rtorsu_trs;
+ struct rcu_torture_one_read_state rtorsu_rtors;
+};
+
+static struct rcu_torture_one_read_state_updown *updownreaders;
+static DEFINE_TORTURE_RANDOM(rcu_torture_updown_rand);
+static int rcu_torture_updown(void *arg);
+
+static enum hrtimer_restart rcu_torture_updown_hrt(struct hrtimer *hrtp)
+{
+ int cpu = raw_smp_processor_id();
+ struct rcu_torture_one_read_state_updown *rtorsup;
+
+ rtorsup = container_of(hrtp, struct rcu_torture_one_read_state_updown, rtorsu_hrt);
+ rcu_torture_one_read_end(&rtorsup->rtorsu_rtors, &rtorsup->rtorsu_trs);
+ WARN_ONCE(rtorsup->rtorsu_nups >= rtorsup->rtorsu_ndowns, "%s: Up without matching down #%zu.\n", __func__, rtorsup - updownreaders);
+ WRITE_ONCE(rtorsup->rtorsu_nups, rtorsup->rtorsu_nups + 1);
+ WRITE_ONCE(rtorsup->rtorsu_nmigrates,
+ rtorsup->rtorsu_nmigrates + (cpu != rtorsup->rtorsu_cpu));
+ smp_store_release(&rtorsup->rtorsu_inuse, false);
+ return HRTIMER_NORESTART;
+}
+
+static int rcu_torture_updown_init(void)
+{
+ int i;
+ struct torture_random_state *rand = &rcu_torture_updown_rand;
+ int ret;
+
+ if (n_up_down < 0)
+ return 0;
+ if (!srcu_torture_have_up_down()) {
+ VERBOSE_TOROUT_STRING("rcu_torture_updown_init: Disabling up/down reader tests due to lack of primitives");
+ return 0;
+ }
+ updownreaders = kcalloc(n_up_down, sizeof(*updownreaders), GFP_KERNEL);
+ if (!updownreaders) {
+ VERBOSE_TOROUT_STRING("rcu_torture_updown_init: Out of memory, disabling up/down reader tests");
+ return -ENOMEM;
+ }
+ for (i = 0; i < n_up_down; i++) {
+ init_rcu_torture_one_read_state(&updownreaders[i].rtorsu_rtors, rand);
+ hrtimer_setup(&updownreaders[i].rtorsu_hrt, rcu_torture_updown_hrt, CLOCK_MONOTONIC,
+ HRTIMER_MODE_REL | HRTIMER_MODE_HARD);
+ torture_random_init(&updownreaders[i].rtorsu_trs);
+ init_rcu_torture_one_read_state(&updownreaders[i].rtorsu_rtors,
+ &updownreaders[i].rtorsu_trs);
+ }
+ ret = torture_create_kthread(rcu_torture_updown, rand, updown_task);
+ if (ret) {
+ kfree(updownreaders);
+ updownreaders = NULL;
+ }
+ return ret;
+}
+
+static void rcu_torture_updown_cleanup(void)
+{
+ struct rcu_torture_one_read_state_updown *rtorsup;
+
+ for (rtorsup = updownreaders; rtorsup < &updownreaders[n_up_down]; rtorsup++) {
+ if (!smp_load_acquire(&rtorsup->rtorsu_inuse))
+ continue;
+ if (hrtimer_cancel(&rtorsup->rtorsu_hrt) || WARN_ON_ONCE(rtorsup->rtorsu_inuse)) {
+ rcu_torture_one_read_end(&rtorsup->rtorsu_rtors, &rtorsup->rtorsu_trs);
+ WARN_ONCE(rtorsup->rtorsu_nups >= rtorsup->rtorsu_ndowns, "%s: Up without matching down #%zu.\n", __func__, rtorsup - updownreaders);
+ WRITE_ONCE(rtorsup->rtorsu_nups, rtorsup->rtorsu_nups + 1);
+ smp_store_release(&rtorsup->rtorsu_inuse, false);
+ }
+
+ }
+ kfree(updownreaders);
+ updownreaders = NULL;
+}
+
+// Do one reader for rcu_torture_updown().
+static void rcu_torture_updown_one(struct rcu_torture_one_read_state_updown *rtorsup)
+{
+ int idx;
+ int rawidx;
+ ktime_t t;
+
+ init_rcu_torture_one_read_state(&rtorsup->rtorsu_rtors, &rtorsup->rtorsu_trs);
+ rawidx = cur_ops->down_read();
+ WRITE_ONCE(rtorsup->rtorsu_ndowns, rtorsup->rtorsu_ndowns + 1);
+ idx = (rawidx << RCUTORTURE_RDR_SHIFT_1) & RCUTORTURE_RDR_MASK_1;
+ rtorsup->rtorsu_rtors.readstate = idx | RCUTORTURE_RDR_UPDOWN;
+ rtorsup->rtorsu_rtors.rtrsp++;
+ rtorsup->rtorsu_cpu = raw_smp_processor_id();
+ if (!rcu_torture_one_read_start(&rtorsup->rtorsu_rtors, &rtorsup->rtorsu_trs, -1)) {
+ WARN_ONCE(rtorsup->rtorsu_nups >= rtorsup->rtorsu_ndowns, "%s: Up without matching down #%zu.\n", __func__, rtorsup - updownreaders);
+ WRITE_ONCE(rtorsup->rtorsu_nups, rtorsup->rtorsu_nups + 1);
+ schedule_timeout_idle(HZ);
+ return;
+ }
+ smp_store_release(&rtorsup->rtorsu_inuse, true);
+ t = torture_random(&rtorsup->rtorsu_trs) & 0xfffff; // One per million.
+ if (t < 10 * 1000)
+ t = 200 * 1000 * 1000;
+ hrtimer_start(&rtorsup->rtorsu_hrt, t, HRTIMER_MODE_REL | HRTIMER_MODE_HARD);
+ smp_mb(); // Sample jiffies after posting hrtimer.
+ rtorsup->rtorsu_j = jiffies; // Not used by hrtimer handler.
+ rtorsup->rtorsu_kt = t;
+}
+
+/*
+ * RCU torture up/down reader kthread, starting RCU readers in kthread
+ * context and ending them in hrtimer handlers. Otherwise similar to
+ * rcu_torture_reader().
+ */
+static int
+rcu_torture_updown(void *arg)
+{
+ unsigned long j;
+ struct rcu_torture_one_read_state_updown *rtorsup;
+
+ VERBOSE_TOROUT_STRING("rcu_torture_updown task started");
+ do {
+ for (rtorsup = updownreaders; rtorsup < &updownreaders[n_up_down]; rtorsup++) {
+ if (torture_must_stop())
+ break;
+ j = smp_load_acquire(&jiffies); // Time before ->rtorsu_inuse.
+ if (smp_load_acquire(&rtorsup->rtorsu_inuse)) {
+ WARN_ONCE(time_after(j, rtorsup->rtorsu_j + 1 + HZ * 10),
+ "hrtimer queued at jiffies %lu for %lld ns took %lu jiffies\n", rtorsup->rtorsu_j, rtorsup->rtorsu_kt, j - rtorsup->rtorsu_j);
+ continue;
+ }
+ rcu_torture_updown_one(rtorsup);
+ }
+ torture_hrtimeout_ms(1, 1000, &rcu_torture_updown_rand);
+ stutter_wait("rcu_torture_updown");
+ } while (!torture_must_stop());
+ rcu_torture_updown_cleanup();
+ torture_kthread_stopping("rcu_torture_updown");
+ return 0;
+}
+
/*
* Randomly Toggle CPUs' callback-offload state. This uses hrtimers to
* increase race probabilities and fuzzes the interval between toggling.
@@ -2441,6 +2659,10 @@ rcu_torture_stats_print(void)
long pipesummary[RCU_TORTURE_PIPE_LEN + 1] = { 0 };
long batchsummary[RCU_TORTURE_PIPE_LEN + 1] = { 0 };
long n_gpwraps = 0;
+ unsigned long ndowns = 0;
+ unsigned long nunexpired = 0;
+ unsigned long nmigrates = 0;
+ unsigned long nups = 0;
struct rcu_torture *rtcp;
static unsigned long rtcv_snap = ULONG_MAX;
static bool splatted;
@@ -2454,10 +2676,18 @@ rcu_torture_stats_print(void)
if (cur_ops->get_gpwrap_count)
n_gpwraps += cur_ops->get_gpwrap_count(cpu);
}
+ if (updownreaders) {
+ for (i = 0; i < n_up_down; i++) {
+ ndowns += READ_ONCE(updownreaders[i].rtorsu_ndowns);
+ nups += READ_ONCE(updownreaders[i].rtorsu_nups);
+ nunexpired += READ_ONCE(updownreaders[i].rtorsu_inuse);
+ nmigrates += READ_ONCE(updownreaders[i].rtorsu_nmigrates);
+ }
+ }
for (i = RCU_TORTURE_PIPE_LEN; i >= 0; i--) {
if (pipesummary[i] != 0)
break;
- }
+ } // The value of variable "i" is used later, so don't clobber it!
pr_alert("%s%s ", torture_type, TORTURE_FLAG);
rtcp = rcu_access_pointer(rcu_torture_current);
@@ -2478,6 +2708,8 @@ rcu_torture_stats_print(void)
n_rcu_torture_boost_failure,
n_rcu_torture_boosts,
atomic_long_read(&n_rcu_torture_timers));
+ if (updownreaders)
+ pr_cont("ndowns: %lu nups: %lu nhrt: %lu nmigrates: %lu ", ndowns, nups, nunexpired, nmigrates);
torture_onoff_stats();
pr_cont("barrier: %ld/%ld:%ld ",
data_race(n_barrier_successes),
@@ -2632,7 +2864,7 @@ rcu_torture_print_module_parms(struct rcu_torture_ops *cur_ops, const char *tag)
"reader_flavor=%x "
"nocbs_nthreads=%d nocbs_toggle=%d "
"test_nmis=%d "
- "preempt_duration=%d preempt_interval=%d\n",
+ "preempt_duration=%d preempt_interval=%d n_up_down=%d\n",
torture_type, tag, nrealreaders, nrealfakewriters,
stat_interval, verbose, test_no_idle_hz, shuffle_interval,
stutter, irqreader, fqs_duration, fqs_holdoff, fqs_stutter,
@@ -2646,7 +2878,7 @@ rcu_torture_print_module_parms(struct rcu_torture_ops *cur_ops, const char *tag)
reader_flavor,
nocbs_nthreads, nocbs_toggle,
test_nmis,
- preempt_duration, preempt_interval);
+ preempt_duration, preempt_interval, n_up_down);
}
static int rcutorture_booster_cleanup(unsigned int cpu)
@@ -3749,6 +3981,10 @@ rcu_torture_cleanup(void)
nocb_tasks = NULL;
}
+ if (updown_task) {
+ torture_stop_kthread(rcu_torture_updown, updown_task);
+ updown_task = NULL;
+ }
if (reader_tasks) {
for (i = 0; i < nrealreaders; i++)
torture_stop_kthread(rcu_torture_reader,
@@ -4245,11 +4481,6 @@ rcu_torture_init(void)
/* Start up the kthreads. */
rcu_torture_write_types();
- firsterr = torture_create_kthread(rcu_torture_writer, NULL,
- writer_task);
- if (torture_init_error(firsterr))
- goto unwind;
-
if (nrealfakewriters > 0) {
fakewriter_tasks = kcalloc(nrealfakewriters,
sizeof(fakewriter_tasks[0]),
@@ -4282,6 +4513,15 @@ rcu_torture_init(void)
if (torture_init_error(firsterr))
goto unwind;
}
+
+ firsterr = torture_create_kthread(rcu_torture_writer, NULL,
+ writer_task);
+ if (torture_init_error(firsterr))
+ goto unwind;
+
+ firsterr = rcu_torture_updown_init();
+ if (torture_init_error(firsterr))
+ goto unwind;
nrealnocbers = nocbs_nthreads;
if (WARN_ON(nrealnocbers < 0))
nrealnocbers = 1;
generated by cgit (git 2.34.1) at 2025-08-01 07:43:17 +0000