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Diffstat (limited to 'kernel/rcu/rcuscale.c')
-rw-r--r--kernel/rcu/rcuscale.c282
1 files changed, 179 insertions, 103 deletions
diff --git a/kernel/rcu/rcuscale.c b/kernel/rcu/rcuscale.c
index e82ec9f9a5d8..ffdb30495e3c 100644
--- a/kernel/rcu/rcuscale.c
+++ b/kernel/rcu/rcuscale.c
@@ -84,15 +84,17 @@ MODULE_AUTHOR("Paul E. McKenney <paulmck@linux.ibm.com>");
#endif
torture_param(bool, gp_async, false, "Use asynchronous GP wait primitives");
-torture_param(int, gp_async_max, 1000, "Max # outstanding waits per reader");
+torture_param(int, gp_async_max, 1000, "Max # outstanding waits per writer");
torture_param(bool, gp_exp, false, "Use expedited GP wait primitives");
torture_param(int, holdoff, 10, "Holdoff time before test start (s)");
+torture_param(int, minruntime, 0, "Minimum run time (s)");
torture_param(int, nreaders, -1, "Number of RCU reader threads");
torture_param(int, nwriters, -1, "Number of RCU updater threads");
torture_param(bool, shutdown, RCUSCALE_SHUTDOWN,
"Shutdown at end of scalability tests.");
torture_param(int, verbose, 1, "Enable verbose debugging printk()s");
torture_param(int, writer_holdoff, 0, "Holdoff (us) between GPs, zero to disable");
+torture_param(int, writer_holdoff_jiffies, 0, "Holdoff (jiffies) between GPs, zero to disable");
torture_param(int, kfree_rcu_test, 0, "Do we run a kfree_rcu() scale test?");
torture_param(int, kfree_mult, 1, "Multiple of kfree_obj size to allocate.");
torture_param(int, kfree_by_call_rcu, 0, "Use call_rcu() to emulate kfree_rcu()?");
@@ -139,6 +141,7 @@ struct rcu_scale_ops {
void (*gp_barrier)(void);
void (*sync)(void);
void (*exp_sync)(void);
+ struct task_struct *(*rso_gp_kthread)(void);
const char *name;
};
@@ -295,6 +298,7 @@ static struct rcu_scale_ops tasks_ops = {
.gp_barrier = rcu_barrier_tasks,
.sync = synchronize_rcu_tasks,
.exp_sync = synchronize_rcu_tasks,
+ .rso_gp_kthread = get_rcu_tasks_gp_kthread,
.name = "tasks"
};
@@ -306,6 +310,44 @@ static struct rcu_scale_ops tasks_ops = {
#endif // #else // #ifdef CONFIG_TASKS_RCU
+#ifdef CONFIG_TASKS_RUDE_RCU
+
+/*
+ * Definitions for RCU-tasks-rude scalability testing.
+ */
+
+static int tasks_rude_scale_read_lock(void)
+{
+ return 0;
+}
+
+static void tasks_rude_scale_read_unlock(int idx)
+{
+}
+
+static struct rcu_scale_ops tasks_rude_ops = {
+ .ptype = RCU_TASKS_RUDE_FLAVOR,
+ .init = rcu_sync_scale_init,
+ .readlock = tasks_rude_scale_read_lock,
+ .readunlock = tasks_rude_scale_read_unlock,
+ .get_gp_seq = rcu_no_completed,
+ .gp_diff = rcu_seq_diff,
+ .async = call_rcu_tasks_rude,
+ .gp_barrier = rcu_barrier_tasks_rude,
+ .sync = synchronize_rcu_tasks_rude,
+ .exp_sync = synchronize_rcu_tasks_rude,
+ .rso_gp_kthread = get_rcu_tasks_rude_gp_kthread,
+ .name = "tasks-rude"
+};
+
+#define TASKS_RUDE_OPS &tasks_rude_ops,
+
+#else // #ifdef CONFIG_TASKS_RUDE_RCU
+
+#define TASKS_RUDE_OPS
+
+#endif // #else // #ifdef CONFIG_TASKS_RUDE_RCU
+
#ifdef CONFIG_TASKS_TRACE_RCU
/*
@@ -334,6 +376,7 @@ static struct rcu_scale_ops tasks_tracing_ops = {
.gp_barrier = rcu_barrier_tasks_trace,
.sync = synchronize_rcu_tasks_trace,
.exp_sync = synchronize_rcu_tasks_trace,
+ .rso_gp_kthread = get_rcu_tasks_trace_gp_kthread,
.name = "tasks-tracing"
};
@@ -410,10 +453,12 @@ rcu_scale_writer(void *arg)
{
int i = 0;
int i_max;
+ unsigned long jdone;
long me = (long)arg;
struct rcu_head *rhp = NULL;
bool started = false, done = false, alldone = false;
u64 t;
+ DEFINE_TORTURE_RANDOM(tr);
u64 *wdp;
u64 *wdpp = writer_durations[me];
@@ -424,7 +469,7 @@ rcu_scale_writer(void *arg)
sched_set_fifo_low(current);
if (holdoff)
- schedule_timeout_uninterruptible(holdoff * HZ);
+ schedule_timeout_idle(holdoff * HZ);
/*
* Wait until rcu_end_inkernel_boot() is called for normal GP tests
@@ -445,9 +490,12 @@ rcu_scale_writer(void *arg)
}
}
+ jdone = jiffies + minruntime * HZ;
do {
if (writer_holdoff)
udelay(writer_holdoff);
+ if (writer_holdoff_jiffies)
+ schedule_timeout_idle(torture_random(&tr) % writer_holdoff_jiffies + 1);
wdp = &wdpp[i];
*wdp = ktime_get_mono_fast_ns();
if (gp_async) {
@@ -475,7 +523,7 @@ retry:
if (!started &&
atomic_read(&n_rcu_scale_writer_started) >= nrealwriters)
started = true;
- if (!done && i >= MIN_MEAS) {
+ if (!done && i >= MIN_MEAS && time_after(jiffies, jdone)) {
done = true;
sched_set_normal(current, 0);
pr_alert("%s%s rcu_scale_writer %ld has %d measurements\n",
@@ -518,91 +566,8 @@ static void
rcu_scale_print_module_parms(struct rcu_scale_ops *cur_ops, const char *tag)
{
pr_alert("%s" SCALE_FLAG
- "--- %s: nreaders=%d nwriters=%d verbose=%d shutdown=%d\n",
- scale_type, tag, nrealreaders, nrealwriters, verbose, shutdown);
-}
-
-static void
-rcu_scale_cleanup(void)
-{
- int i;
- int j;
- int ngps = 0;
- u64 *wdp;
- u64 *wdpp;
-
- /*
- * Would like warning at start, but everything is expedited
- * during the mid-boot phase, so have to wait till the end.
- */
- if (rcu_gp_is_expedited() && !rcu_gp_is_normal() && !gp_exp)
- SCALEOUT_ERRSTRING("All grace periods expedited, no normal ones to measure!");
- if (rcu_gp_is_normal() && gp_exp)
- SCALEOUT_ERRSTRING("All grace periods normal, no expedited ones to measure!");
- if (gp_exp && gp_async)
- SCALEOUT_ERRSTRING("No expedited async GPs, so went with async!");
-
- if (torture_cleanup_begin())
- return;
- if (!cur_ops) {
- torture_cleanup_end();
- return;
- }
-
- if (reader_tasks) {
- for (i = 0; i < nrealreaders; i++)
- torture_stop_kthread(rcu_scale_reader,
- reader_tasks[i]);
- kfree(reader_tasks);
- }
-
- if (writer_tasks) {
- for (i = 0; i < nrealwriters; i++) {
- torture_stop_kthread(rcu_scale_writer,
- writer_tasks[i]);
- if (!writer_n_durations)
- continue;
- j = writer_n_durations[i];
- pr_alert("%s%s writer %d gps: %d\n",
- scale_type, SCALE_FLAG, i, j);
- ngps += j;
- }
- pr_alert("%s%s start: %llu end: %llu duration: %llu gps: %d batches: %ld\n",
- scale_type, SCALE_FLAG,
- t_rcu_scale_writer_started, t_rcu_scale_writer_finished,
- t_rcu_scale_writer_finished -
- t_rcu_scale_writer_started,
- ngps,
- rcuscale_seq_diff(b_rcu_gp_test_finished,
- b_rcu_gp_test_started));
- for (i = 0; i < nrealwriters; i++) {
- if (!writer_durations)
- break;
- if (!writer_n_durations)
- continue;
- wdpp = writer_durations[i];
- if (!wdpp)
- continue;
- for (j = 0; j < writer_n_durations[i]; j++) {
- wdp = &wdpp[j];
- pr_alert("%s%s %4d writer-duration: %5d %llu\n",
- scale_type, SCALE_FLAG,
- i, j, *wdp);
- if (j % 100 == 0)
- schedule_timeout_uninterruptible(1);
- }
- kfree(writer_durations[i]);
- }
- kfree(writer_tasks);
- kfree(writer_durations);
- kfree(writer_n_durations);
- }
-
- /* Do torture-type-specific cleanup operations. */
- if (cur_ops->cleanup != NULL)
- cur_ops->cleanup();
-
- torture_cleanup_end();
+ "--- %s: gp_async=%d gp_async_max=%d gp_exp=%d holdoff=%d minruntime=%d nreaders=%d nwriters=%d writer_holdoff=%d writer_holdoff_jiffies=%d verbose=%d shutdown=%d\n",
+ scale_type, tag, gp_async, gp_async_max, gp_exp, holdoff, minruntime, nrealreaders, nrealwriters, writer_holdoff, writer_holdoff_jiffies, verbose, shutdown);
}
/*
@@ -625,20 +590,6 @@ static int compute_real(int n)
}
/*
- * RCU scalability shutdown kthread. Just waits to be awakened, then shuts
- * down system.
- */
-static int
-rcu_scale_shutdown(void *arg)
-{
- wait_event_idle(shutdown_wq, atomic_read(&n_rcu_scale_writer_finished) >= nrealwriters);
- smp_mb(); /* Wake before output. */
- rcu_scale_cleanup();
- kernel_power_off();
- return -EINVAL;
-}
-
-/*
* kfree_rcu() scalability tests: Start a kfree_rcu() loop on all CPUs for number
* of iterations and measure total time and number of GP for all iterations to complete.
*/
@@ -653,6 +604,8 @@ static struct task_struct **kfree_reader_tasks;
static int kfree_nrealthreads;
static atomic_t n_kfree_scale_thread_started;
static atomic_t n_kfree_scale_thread_ended;
+static struct task_struct *kthread_tp;
+static u64 kthread_stime;
struct kfree_obj {
char kfree_obj[8];
@@ -798,6 +751,10 @@ kfree_scale_init(void)
unsigned long jif_start;
unsigned long orig_jif;
+ pr_alert("%s" SCALE_FLAG
+ "--- kfree_rcu_test: kfree_mult=%d kfree_by_call_rcu=%d kfree_nthreads=%d kfree_alloc_num=%d kfree_loops=%d kfree_rcu_test_double=%d kfree_rcu_test_single=%d\n",
+ scale_type, kfree_mult, kfree_by_call_rcu, kfree_nthreads, kfree_alloc_num, kfree_loops, kfree_rcu_test_double, kfree_rcu_test_single);
+
// Also, do a quick self-test to ensure laziness is as much as
// expected.
if (kfree_by_call_rcu && !IS_ENABLED(CONFIG_RCU_LAZY)) {
@@ -874,13 +831,127 @@ unwind:
return firsterr;
}
+static void
+rcu_scale_cleanup(void)
+{
+ int i;
+ int j;
+ int ngps = 0;
+ u64 *wdp;
+ u64 *wdpp;
+
+ /*
+ * Would like warning at start, but everything is expedited
+ * during the mid-boot phase, so have to wait till the end.
+ */
+ if (rcu_gp_is_expedited() && !rcu_gp_is_normal() && !gp_exp)
+ SCALEOUT_ERRSTRING("All grace periods expedited, no normal ones to measure!");
+ if (rcu_gp_is_normal() && gp_exp)
+ SCALEOUT_ERRSTRING("All grace periods normal, no expedited ones to measure!");
+ if (gp_exp && gp_async)
+ SCALEOUT_ERRSTRING("No expedited async GPs, so went with async!");
+
+ // If built-in, just report all of the GP kthread's CPU time.
+ if (IS_BUILTIN(CONFIG_RCU_SCALE_TEST) && !kthread_tp && cur_ops->rso_gp_kthread)
+ kthread_tp = cur_ops->rso_gp_kthread();
+ if (kthread_tp) {
+ u32 ns;
+ u64 us;
+
+ kthread_stime = kthread_tp->stime - kthread_stime;
+ us = div_u64_rem(kthread_stime, 1000, &ns);
+ pr_info("rcu_scale: Grace-period kthread CPU time: %llu.%03u us\n", us, ns);
+ show_rcu_gp_kthreads();
+ }
+ if (kfree_rcu_test) {
+ kfree_scale_cleanup();
+ return;
+ }
+
+ if (torture_cleanup_begin())
+ return;
+ if (!cur_ops) {
+ torture_cleanup_end();
+ return;
+ }
+
+ if (reader_tasks) {
+ for (i = 0; i < nrealreaders; i++)
+ torture_stop_kthread(rcu_scale_reader,
+ reader_tasks[i]);
+ kfree(reader_tasks);
+ }
+
+ if (writer_tasks) {
+ for (i = 0; i < nrealwriters; i++) {
+ torture_stop_kthread(rcu_scale_writer,
+ writer_tasks[i]);
+ if (!writer_n_durations)
+ continue;
+ j = writer_n_durations[i];
+ pr_alert("%s%s writer %d gps: %d\n",
+ scale_type, SCALE_FLAG, i, j);
+ ngps += j;
+ }
+ pr_alert("%s%s start: %llu end: %llu duration: %llu gps: %d batches: %ld\n",
+ scale_type, SCALE_FLAG,
+ t_rcu_scale_writer_started, t_rcu_scale_writer_finished,
+ t_rcu_scale_writer_finished -
+ t_rcu_scale_writer_started,
+ ngps,
+ rcuscale_seq_diff(b_rcu_gp_test_finished,
+ b_rcu_gp_test_started));
+ for (i = 0; i < nrealwriters; i++) {
+ if (!writer_durations)
+ break;
+ if (!writer_n_durations)
+ continue;
+ wdpp = writer_durations[i];
+ if (!wdpp)
+ continue;
+ for (j = 0; j < writer_n_durations[i]; j++) {
+ wdp = &wdpp[j];
+ pr_alert("%s%s %4d writer-duration: %5d %llu\n",
+ scale_type, SCALE_FLAG,
+ i, j, *wdp);
+ if (j % 100 == 0)
+ schedule_timeout_uninterruptible(1);
+ }
+ kfree(writer_durations[i]);
+ }
+ kfree(writer_tasks);
+ kfree(writer_durations);
+ kfree(writer_n_durations);
+ }
+
+ /* Do torture-type-specific cleanup operations. */
+ if (cur_ops->cleanup != NULL)
+ cur_ops->cleanup();
+
+ torture_cleanup_end();
+}
+
+/*
+ * RCU scalability shutdown kthread. Just waits to be awakened, then shuts
+ * down system.
+ */
+static int
+rcu_scale_shutdown(void *arg)
+{
+ wait_event_idle(shutdown_wq, atomic_read(&n_rcu_scale_writer_finished) >= nrealwriters);
+ smp_mb(); /* Wake before output. */
+ rcu_scale_cleanup();
+ kernel_power_off();
+ return -EINVAL;
+}
+
static int __init
rcu_scale_init(void)
{
long i;
int firsterr = 0;
static struct rcu_scale_ops *scale_ops[] = {
- &rcu_ops, &srcu_ops, &srcud_ops, TASKS_OPS TASKS_TRACING_OPS
+ &rcu_ops, &srcu_ops, &srcud_ops, TASKS_OPS TASKS_RUDE_OPS TASKS_TRACING_OPS
};
if (!torture_init_begin(scale_type, verbose))
@@ -905,6 +976,11 @@ rcu_scale_init(void)
if (cur_ops->init)
cur_ops->init();
+ if (cur_ops->rso_gp_kthread) {
+ kthread_tp = cur_ops->rso_gp_kthread();
+ if (kthread_tp)
+ kthread_stime = kthread_tp->stime;
+ }
if (kfree_rcu_test)
return kfree_scale_init();