[PATCH v4 1/2] rcu/rcuscale: Move rcu_scale_*() after kfree_scale_cleanup()

From: Qiuxu Zhuo
Date: Wed Mar 22 2023 - 07:43:48 EST


Move rcu_scale_cleanup() and rcu_scale_shutdown() functions after
kfree_scale_cleanup(). There are no function changes.

The intention of this moving is a preparation for a subsequent patch
that will fix a call-trace bug by invoking kfree_scale_cleanup() from
rcu_scale_cleanup() without the declaration of kfree_scale_cleanup().

Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@xxxxxxxxx>
---
kernel/rcu/rcuscale.c | 194 +++++++++++++++++++++---------------------
1 file changed, 97 insertions(+), 97 deletions(-)

diff --git a/kernel/rcu/rcuscale.c b/kernel/rcu/rcuscale.c
index e82ec9f9a5d8..7e8965b0827a 100644
--- a/kernel/rcu/rcuscale.c
+++ b/kernel/rcu/rcuscale.c
@@ -522,89 +522,6 @@ rcu_scale_print_module_parms(struct rcu_scale_ops *cur_ops, const char *tag)
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();
-}
-
/*
* Return the number if non-negative. If -1, the number of CPUs.
* If less than -1, that much less than the number of CPUs, but
@@ -624,20 +541,6 @@ static int compute_real(int n)
return nr;
}

-/*
- * 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.
@@ -874,6 +777,103 @@ kfree_scale_init(void)
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 (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)
{
--
2.17.1