locking/local_lock: Support Clang's context analysis

Add support for Clang's context analysis for local_lock_t and
local_trylock_t.

Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/20251219154418.3592607-20-elver@google.com

1 files changed, 73 insertions, 0 deletions

diff --git a/lib/test_context-analysis.c b/lib/test_context-analysis.c
index 1c96c56cf873..003e64cac540 100644
--- a/lib/test_context-analysis.c
+++ b/lib/test_context-analysis.c
@@ -6,7 +6,9 @@
 
 #include <linux/bit_spinlock.h>
 #include <linux/build_bug.h>
+#include <linux/local_lock.h>
 #include <linux/mutex.h>
+#include <linux/percpu.h>
 #include <linux/rcupdate.h>
 #include <linux/rwsem.h>
 #include <linux/seqlock.h>
@@ -458,3 +460,74 @@ static void __used test_srcu_guard(struct test_srcu_data *d)
 	{ guard(srcu_fast)(&d->srcu); (void)srcu_dereference(d->data, &d->srcu); }
 	{ guard(srcu_fast_notrace)(&d->srcu); (void)srcu_dereference(d->data, &d->srcu); }
 }
+
+struct test_local_lock_data {
+	local_lock_t lock;
+	int counter __guarded_by(&lock);
+};
+
+static DEFINE_PER_CPU(struct test_local_lock_data, test_local_lock_data) = {
+	.lock = INIT_LOCAL_LOCK(lock),
+};
+
+static void __used test_local_lock_init(struct test_local_lock_data *d)
+{
+	local_lock_init(&d->lock);
+	d->counter = 0;
+}
+
+static void __used test_local_lock(void)
+{
+	unsigned long flags;
+
+	local_lock(&test_local_lock_data.lock);
+	this_cpu_add(test_local_lock_data.counter, 1);
+	local_unlock(&test_local_lock_data.lock);
+
+	local_lock_irq(&test_local_lock_data.lock);
+	this_cpu_add(test_local_lock_data.counter, 1);
+	local_unlock_irq(&test_local_lock_data.lock);
+
+	local_lock_irqsave(&test_local_lock_data.lock, flags);
+	this_cpu_add(test_local_lock_data.counter, 1);
+	local_unlock_irqrestore(&test_local_lock_data.lock, flags);
+
+	local_lock_nested_bh(&test_local_lock_data.lock);
+	this_cpu_add(test_local_lock_data.counter, 1);
+	local_unlock_nested_bh(&test_local_lock_data.lock);
+}
+
+static void __used test_local_lock_guard(void)
+{
+	{ guard(local_lock)(&test_local_lock_data.lock); this_cpu_add(test_local_lock_data.counter, 1); }
+	{ guard(local_lock_irq)(&test_local_lock_data.lock); this_cpu_add(test_local_lock_data.counter, 1); }
+	{ guard(local_lock_irqsave)(&test_local_lock_data.lock); this_cpu_add(test_local_lock_data.counter, 1); }
+	{ guard(local_lock_nested_bh)(&test_local_lock_data.lock); this_cpu_add(test_local_lock_data.counter, 1); }
+}
+
+struct test_local_trylock_data {
+	local_trylock_t lock;
+	int counter __guarded_by(&lock);
+};
+
+static DEFINE_PER_CPU(struct test_local_trylock_data, test_local_trylock_data) = {
+	.lock = INIT_LOCAL_TRYLOCK(lock),
+};
+
+static void __used test_local_trylock_init(struct test_local_trylock_data *d)
+{
+	local_trylock_init(&d->lock);
+	d->counter = 0;
+}
+
+static void __used test_local_trylock(void)
+{
+	local_lock(&test_local_trylock_data.lock);
+	this_cpu_add(test_local_trylock_data.counter, 1);
+	local_unlock(&test_local_trylock_data.lock);
+
+	if (local_trylock(&test_local_trylock_data.lock)) {
+		this_cpu_add(test_local_trylock_data.counter, 1);
+		local_unlock(&test_local_trylock_data.lock);
+	}
+}