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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /arch/mips/kernel/spinlock_test.c
parentInitial commit. (diff)
downloadlinux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz
linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip
Adding upstream version 5.10.209.upstream/5.10.209
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/mips/kernel/spinlock_test.c')
-rw-r--r--arch/mips/kernel/spinlock_test.c127
1 files changed, 127 insertions, 0 deletions
diff --git a/arch/mips/kernel/spinlock_test.c b/arch/mips/kernel/spinlock_test.c
new file mode 100644
index 000000000..ab4e3e1b1
--- /dev/null
+++ b/arch/mips/kernel/spinlock_test.c
@@ -0,0 +1,127 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/init.h>
+#include <linux/kthread.h>
+#include <linux/hrtimer.h>
+#include <linux/fs.h>
+#include <linux/debugfs.h>
+#include <linux/export.h>
+#include <linux/spinlock.h>
+#include <asm/debug.h>
+
+static int ss_get(void *data, u64 *val)
+{
+ ktime_t start, finish;
+ int loops;
+ int cont;
+ DEFINE_RAW_SPINLOCK(ss_spin);
+
+ loops = 1000000;
+ cont = 1;
+
+ start = ktime_get();
+
+ while (cont) {
+ raw_spin_lock(&ss_spin);
+ loops--;
+ if (loops == 0)
+ cont = 0;
+ raw_spin_unlock(&ss_spin);
+ }
+
+ finish = ktime_get();
+
+ *val = ktime_us_delta(finish, start);
+
+ return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(fops_ss, ss_get, NULL, "%llu\n");
+
+
+
+struct spin_multi_state {
+ raw_spinlock_t lock;
+ atomic_t start_wait;
+ atomic_t enter_wait;
+ atomic_t exit_wait;
+ int loops;
+};
+
+struct spin_multi_per_thread {
+ struct spin_multi_state *state;
+ ktime_t start;
+};
+
+static int multi_other(void *data)
+{
+ int loops;
+ int cont;
+ struct spin_multi_per_thread *pt = data;
+ struct spin_multi_state *s = pt->state;
+
+ loops = s->loops;
+ cont = 1;
+
+ atomic_dec(&s->enter_wait);
+
+ while (atomic_read(&s->enter_wait))
+ ; /* spin */
+
+ pt->start = ktime_get();
+
+ atomic_dec(&s->start_wait);
+
+ while (atomic_read(&s->start_wait))
+ ; /* spin */
+
+ while (cont) {
+ raw_spin_lock(&s->lock);
+ loops--;
+ if (loops == 0)
+ cont = 0;
+ raw_spin_unlock(&s->lock);
+ }
+
+ atomic_dec(&s->exit_wait);
+ while (atomic_read(&s->exit_wait))
+ ; /* spin */
+ return 0;
+}
+
+static int multi_get(void *data, u64 *val)
+{
+ ktime_t finish;
+ struct spin_multi_state ms;
+ struct spin_multi_per_thread t1, t2;
+
+ ms.lock = __RAW_SPIN_LOCK_UNLOCKED("multi_get");
+ ms.loops = 1000000;
+
+ atomic_set(&ms.start_wait, 2);
+ atomic_set(&ms.enter_wait, 2);
+ atomic_set(&ms.exit_wait, 2);
+ t1.state = &ms;
+ t2.state = &ms;
+
+ kthread_run(multi_other, &t2, "multi_get");
+
+ multi_other(&t1);
+
+ finish = ktime_get();
+
+ *val = ktime_us_delta(finish, t1.start);
+
+ return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(fops_multi, multi_get, NULL, "%llu\n");
+
+static int __init spinlock_test(void)
+{
+ debugfs_create_file("spin_single", S_IRUGO, mips_debugfs_dir, NULL,
+ &fops_ss);
+ debugfs_create_file("spin_multi", S_IRUGO, mips_debugfs_dir, NULL,
+ &fops_multi);
+ return 0;
+}
+device_initcall(spinlock_test);