[PATCH tip/core/rcu 04/17] rcutorture: Break up too-long rcu_torture_fwd_prog() function
From: "Paul E. McKenney"
This commit splits rcu_torture_fwd_prog_nr() and rcu_torture_fwd_prog_cr()
functions out of rcu_torture_fwd_prog() in order to reduce indentation
pain and because rcu_torture_fwd_prog() was getting a bit too long.
In addition, this will enable easier conditional execution of the
rcu_torture_fwd_prog_cr() function, which can give false-positive
failures in some NO_HZ_FULL configurations due to overloading the
housekeeping CPUs.
Signed-off-by: Paul E. McKenney
---
kernel/rcu/rcutorture.c | 254 +---
1 file changed, 135 insertions(+), 119 deletions(-)
diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
index 17f480129a78..bcc33bb8d9a6 100644
--- a/kernel/rcu/rcutorture.c
+++ b/kernel/rcu/rcutorture.c
@@ -1650,15 +1650,70 @@ static void rcu_torture_fwd_cb_cr(struct rcu_head *rhp)
spin_unlock(_fwd_lock);
}
-/* Carry out grace-period forward-progress testing. */
-static int rcu_torture_fwd_prog(void *args)
+/* Carry out need_resched()/cond_resched() forward-progress testing. */
+static void rcu_torture_fwd_prog_nr(int *tested, int *tested_tries)
{
unsigned long cver;
unsigned long dur;
struct fwd_cb_state fcs;
unsigned long gps;
- int i;
int idx;
+ int sd;
+ int sd4;
+ bool selfpropcb = false;
+ unsigned long stopat;
+ static DEFINE_TORTURE_RANDOM(trs);
+
+ if (cur_ops->call && cur_ops->sync && cur_ops->cb_barrier) {
+ init_rcu_head_on_stack();
+ selfpropcb = true;
+ }
+
+ /* Tight loop containing cond_resched(). */
+ if (selfpropcb) {
+ WRITE_ONCE(fcs.stop, 0);
+ cur_ops->call(, rcu_torture_fwd_prog_cb);
+ }
+ cver = READ_ONCE(rcu_torture_current_version);
+ gps = cur_ops->get_gp_seq();
+ sd = cur_ops->stall_dur() + 1;
+ sd4 = (sd + fwd_progress_div - 1) / fwd_progress_div;
+ dur = sd4 + torture_random() % (sd - sd4);
+ rcu_fwd_startat = jiffies;
+ stopat = rcu_fwd_startat + dur;
+ while (time_before(jiffies, stopat) && !torture_must_stop()) {
+ idx = cur_ops->readlock();
+ udelay(10);
+ cur_ops->readunlock(idx);
+ if (!fwd_progress_need_resched || need_resched())
+ cond_resched();
+ }
+ (*tested_tries)++;
+ if (!time_before(jiffies, stopat) && !torture_must_stop()) {
+ (*tested)++;
+ cver = READ_ONCE(rcu_torture_current_version) - cver;
+ gps = rcutorture_seq_diff(cur_ops->get_gp_seq(), gps);
+ WARN_ON(!cver && gps < 2);
+ pr_alert("%s: Duration %ld cver %ld gps %ld\n", __func__, dur,
cver, gps);
+ }
+ if (selfpropcb) {
+ WRITE_ONCE(fcs.stop, 1);
+ cur_ops->sync(); /* Wait for running CB to complete. */
+ cur_ops->cb_barrier(); /* Wait for queued callbacks. */
+ }
+
+ if (selfpropcb) {
+ WARN_ON(READ_ONCE(fcs.stop) != 2);
+ destroy_rcu_head_on_stack();
+ }
+}
+
+/* Carry out call_rcu() forward-progress testing. */
+static void rcu_torture_fwd_prog_cr(void)
+{
+ unsigned long cver;
+ unsigned long gps;
+ int i;
int j;
long n_launders;
long n_launders_cb_snap;
@@ -1667,136 +1722,97 @@ static int rcu_torture_fwd_prog(void *args)
long n_max_gps;
struct rcu_fwd_cb *rfcp;
struct rcu_fwd_cb *rfcpn;
- int sd;
- int sd4;
- bool selfpropcb = false;
unsigned long stopat;
unsigned long stoppedat;
+
+ /* Loop continuously posting RCU callbacks. */
+ WRITE_ONCE(rcu_fwd_cb_nodelay, true);
+ cur_ops->sync(); /* Later readers see above write. */
+ rcu_fwd_startat = jiffies;
+ stopat = rcu_fwd_startat + MAX_FWD_CB_JIFFIES;
+ n_launders = 0;
+ n_launders_cb = 0;
+ n_launders_sa = 0;
+ n_max_cbs = 0;
+ n_max_gps = 0;
+ for (i = 0; i < ARRAY_SIZE(n_launders_hist); i++)
+ n_launders_hist[i] = 0;
+ cver = READ_ONCE(rcu_torture_current_version);
+ gps = cur_ops->get_gp_seq();
+ while (time_before(jiffies, stopat) && !torture_must_stop()) {
+ rfcp = READ_ONCE(rcu_fwd_cb_head);
+ rfcpn = NULL;
+ if (rfcp)
+ rfcpn = READ_ONCE(rfcp->rfc_next);
+ if (rfcpn) {
+ if (rfcp->rfc_gps >= MIN_FWD_CB_LAUNDERS &&
+ ++n_max_gps >= MIN_FWD_CBS_LAUNDERED)
+ break;
+ rcu_fwd_cb_head = rfcpn;
+ n_launders++;
+ n_launders_sa++;
+ } else {
+ rfcp = kmalloc(sizeof(*rfcp), GFP_KERNEL);
+ if (WARN_ON_ONCE(!rfcp)) {
+
[PATCH tip/core/rcu 04/17] rcutorture: Break up too-long rcu_torture_fwd_prog() function
From: "Paul E. McKenney"
This commit splits rcu_torture_fwd_prog_nr() and rcu_torture_fwd_prog_cr()
functions out of rcu_torture_fwd_prog() in order to reduce indentation
pain and because rcu_torture_fwd_prog() was getting a bit too long.
In addition, this will enable easier conditional execution of the
rcu_torture_fwd_prog_cr() function, which can give false-positive
failures in some NO_HZ_FULL configurations due to overloading the
housekeeping CPUs.
Signed-off-by: Paul E. McKenney
---
kernel/rcu/rcutorture.c | 254 +---
1 file changed, 135 insertions(+), 119 deletions(-)
diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
index 17f480129a78..bcc33bb8d9a6 100644
--- a/kernel/rcu/rcutorture.c
+++ b/kernel/rcu/rcutorture.c
@@ -1650,15 +1650,70 @@ static void rcu_torture_fwd_cb_cr(struct rcu_head *rhp)
spin_unlock(_fwd_lock);
}
-/* Carry out grace-period forward-progress testing. */
-static int rcu_torture_fwd_prog(void *args)
+/* Carry out need_resched()/cond_resched() forward-progress testing. */
+static void rcu_torture_fwd_prog_nr(int *tested, int *tested_tries)
{
unsigned long cver;
unsigned long dur;
struct fwd_cb_state fcs;
unsigned long gps;
- int i;
int idx;
+ int sd;
+ int sd4;
+ bool selfpropcb = false;
+ unsigned long stopat;
+ static DEFINE_TORTURE_RANDOM(trs);
+
+ if (cur_ops->call && cur_ops->sync && cur_ops->cb_barrier) {
+ init_rcu_head_on_stack();
+ selfpropcb = true;
+ }
+
+ /* Tight loop containing cond_resched(). */
+ if (selfpropcb) {
+ WRITE_ONCE(fcs.stop, 0);
+ cur_ops->call(, rcu_torture_fwd_prog_cb);
+ }
+ cver = READ_ONCE(rcu_torture_current_version);
+ gps = cur_ops->get_gp_seq();
+ sd = cur_ops->stall_dur() + 1;
+ sd4 = (sd + fwd_progress_div - 1) / fwd_progress_div;
+ dur = sd4 + torture_random() % (sd - sd4);
+ rcu_fwd_startat = jiffies;
+ stopat = rcu_fwd_startat + dur;
+ while (time_before(jiffies, stopat) && !torture_must_stop()) {
+ idx = cur_ops->readlock();
+ udelay(10);
+ cur_ops->readunlock(idx);
+ if (!fwd_progress_need_resched || need_resched())
+ cond_resched();
+ }
+ (*tested_tries)++;
+ if (!time_before(jiffies, stopat) && !torture_must_stop()) {
+ (*tested)++;
+ cver = READ_ONCE(rcu_torture_current_version) - cver;
+ gps = rcutorture_seq_diff(cur_ops->get_gp_seq(), gps);
+ WARN_ON(!cver && gps < 2);
+ pr_alert("%s: Duration %ld cver %ld gps %ld\n", __func__, dur,
cver, gps);
+ }
+ if (selfpropcb) {
+ WRITE_ONCE(fcs.stop, 1);
+ cur_ops->sync(); /* Wait for running CB to complete. */
+ cur_ops->cb_barrier(); /* Wait for queued callbacks. */
+ }
+
+ if (selfpropcb) {
+ WARN_ON(READ_ONCE(fcs.stop) != 2);
+ destroy_rcu_head_on_stack();
+ }
+}
+
+/* Carry out call_rcu() forward-progress testing. */
+static void rcu_torture_fwd_prog_cr(void)
+{
+ unsigned long cver;
+ unsigned long gps;
+ int i;
int j;
long n_launders;
long n_launders_cb_snap;
@@ -1667,136 +1722,97 @@ static int rcu_torture_fwd_prog(void *args)
long n_max_gps;
struct rcu_fwd_cb *rfcp;
struct rcu_fwd_cb *rfcpn;
- int sd;
- int sd4;
- bool selfpropcb = false;
unsigned long stopat;
unsigned long stoppedat;
+
+ /* Loop continuously posting RCU callbacks. */
+ WRITE_ONCE(rcu_fwd_cb_nodelay, true);
+ cur_ops->sync(); /* Later readers see above write. */
+ rcu_fwd_startat = jiffies;
+ stopat = rcu_fwd_startat + MAX_FWD_CB_JIFFIES;
+ n_launders = 0;
+ n_launders_cb = 0;
+ n_launders_sa = 0;
+ n_max_cbs = 0;
+ n_max_gps = 0;
+ for (i = 0; i < ARRAY_SIZE(n_launders_hist); i++)
+ n_launders_hist[i] = 0;
+ cver = READ_ONCE(rcu_torture_current_version);
+ gps = cur_ops->get_gp_seq();
+ while (time_before(jiffies, stopat) && !torture_must_stop()) {
+ rfcp = READ_ONCE(rcu_fwd_cb_head);
+ rfcpn = NULL;
+ if (rfcp)
+ rfcpn = READ_ONCE(rfcp->rfc_next);
+ if (rfcpn) {
+ if (rfcp->rfc_gps >= MIN_FWD_CB_LAUNDERS &&
+ ++n_max_gps >= MIN_FWD_CBS_LAUNDERED)
+ break;
+ rcu_fwd_cb_head = rfcpn;
+ n_launders++;
+ n_launders_sa++;
+ } else {
+ rfcp = kmalloc(sizeof(*rfcp), GFP_KERNEL);
+ if (WARN_ON_ONCE(!rfcp)) {
+
