[PATCH RFC v6 06/21] dept: Apply Dept to wait_for_completion()/complete()

From: Byungchul Park
Date: Wed May 04 2022 - 04:52:28 EST


Makes Dept able to track dependencies by
wait_for_completion()/complete().

Signed-off-by: Byungchul Park <byungchul.park@xxxxxxx>
---
include/linux/completion.h | 44 ++++++++++++++++++++++++++++++++++++++++++--
kernel/sched/completion.c | 12 ++++++++++--
2 files changed, 52 insertions(+), 4 deletions(-)

diff --git a/include/linux/completion.h b/include/linux/completion.h
index 51d9ab0..358c656 100644
--- a/include/linux/completion.h
+++ b/include/linux/completion.h
@@ -26,14 +26,45 @@
struct completion {
unsigned int done;
struct swait_queue_head wait;
+ struct dept_map dmap;
};

+#ifdef CONFIG_DEPT
+#define dept_wfc_nocheck(m) dept_map_nocheck(m)
+#define dept_wfc_init(m, k, s, n) dept_map_init(m, k, s, n)
+#define dept_wfc_reinit(m) dept_map_reinit(m)
+#define dept_wfc_wait(m, ip) \
+do { \
+ dept_ask_event(m); \
+ dept_wait(m, 1UL, ip, __func__, 0); \
+} while (0)
+#define dept_wfc_complete(m, ip) dept_event(m, 1UL, ip, __func__)
+#define dept_wfc_enter(m, ip) dept_ecxt_enter(m, 1UL, ip, "completion_context_enter", "complete", 0)
+#define dept_wfc_exit(m, ip) dept_ecxt_exit(m, 1UL, ip)
+#else
+#define dept_wfc_nocheck(m) do { } while (0)
+#define dept_wfc_init(m, k, s, n) do { (void)(n); (void)(k); } while (0)
+#define dept_wfc_reinit(m) do { } while (0)
+#define dept_wfc_wait(m, ip) do { } while (0)
+#define dept_wfc_complete(m, ip) do { } while (0)
+#define dept_wfc_enter(m, ip) do { } while (0)
+#define dept_wfc_exit(m, ip) do { } while (0)
+#endif
+
+#define init_completion_nocheck(x) __init_completion(x, NULL, #x, false)
+#define init_completion(x) \
+ do { \
+ static struct dept_key __dkey; \
+ __init_completion(x, &__dkey, #x, true); \
+ } while (0)
+
#define init_completion_map(x, m) init_completion(x)
static inline void complete_acquire(struct completion *x) {}
static inline void complete_release(struct completion *x) {}

#define COMPLETION_INITIALIZER(work) \
- { 0, __SWAIT_QUEUE_HEAD_INITIALIZER((work).wait) }
+ { 0, __SWAIT_QUEUE_HEAD_INITIALIZER((work).wait), \
+ .dmap = DEPT_MAP_INITIALIZER(work) }

#define COMPLETION_INITIALIZER_ONSTACK_MAP(work, map) \
(*({ init_completion_map(&(work), &(map)); &(work); }))
@@ -81,9 +112,17 @@ static inline void complete_release(struct completion *x) {}
* This inline function will initialize a dynamically created completion
* structure.
*/
-static inline void init_completion(struct completion *x)
+static inline void __init_completion(struct completion *x,
+ struct dept_key *dkey,
+ const char *name, bool check)
{
x->done = 0;
+
+ if (check)
+ dept_wfc_init(&x->dmap, dkey, 0, name);
+ else
+ dept_wfc_nocheck(&x->dmap);
+
init_swait_queue_head(&x->wait);
}

@@ -97,6 +136,7 @@ static inline void init_completion(struct completion *x)
static inline void reinit_completion(struct completion *x)
{
x->done = 0;
+ dept_wfc_reinit(&x->dmap);
}

extern void wait_for_completion(struct completion *);
diff --git a/kernel/sched/completion.c b/kernel/sched/completion.c
index 35f15c2..4cf0cfe 100644
--- a/kernel/sched/completion.c
+++ b/kernel/sched/completion.c
@@ -29,6 +29,7 @@ void complete(struct completion *x)
{
unsigned long flags;

+ dept_wfc_complete(&x->dmap, _RET_IP_);
raw_spin_lock_irqsave(&x->wait.lock, flags);

if (x->done != UINT_MAX)
@@ -58,6 +59,7 @@ void complete_all(struct completion *x)
{
unsigned long flags;

+ dept_wfc_complete(&x->dmap, _RET_IP_);
lockdep_assert_RT_in_threaded_ctx();

raw_spin_lock_irqsave(&x->wait.lock, flags);
@@ -112,17 +114,23 @@ void complete_all(struct completion *x)
}

static long __sched
-wait_for_common(struct completion *x, long timeout, int state)
+_wait_for_common(struct completion *x, long timeout, int state)
{
return __wait_for_common(x, schedule_timeout, timeout, state);
}

static long __sched
-wait_for_common_io(struct completion *x, long timeout, int state)
+_wait_for_common_io(struct completion *x, long timeout, int state)
{
return __wait_for_common(x, io_schedule_timeout, timeout, state);
}

+#define wait_for_common(x, t, s) \
+({ dept_wfc_wait(&(x)->dmap, _RET_IP_); _wait_for_common(x, t, s); })
+
+#define wait_for_common_io(x, t, s) \
+({ dept_wfc_wait(&(x)->dmap, _RET_IP_); _wait_for_common_io(x, t, s); })
+
/**
* wait_for_completion: - waits for completion of a task
* @x: holds the state of this particular completion
--
1.9.1