On 12/15/23 22:26, Kent Overstreet wrote:
Trimming down sched.h dependencies: we don't want to include more than
the base types.
Signed-off-by: Kent Overstreet<kent.overstreet@xxxxxxxxx>
Cc: Peter Zijlstra<peterz@xxxxxxxxxxxxx>
Cc: Ingo Molnar<mingo@xxxxxxxxxx>
Cc: Will Deacon<will@xxxxxxxxxx>
Cc: Waiman Long<longman@xxxxxxxxxx>
Cc: Boqun Feng<boqun.feng@xxxxxxxxx>
Signed-off-by: Kent Overstreet<kent.overstreet@xxxxxxxxx>
---
include/linux/mutex.h | 52 +--------------------------
include/linux/mutex_types.h | 71 +++++++++++++++++++++++++++++++++++++
include/linux/sched.h | 2 +-
3 files changed, 73 insertions(+), 52 deletions(-)
create mode 100644 include/linux/mutex_types.h
diff --git a/include/linux/mutex.h b/include/linux/mutex.h
index a33aa9eb9fc3..0dfba5df6524 100644
--- a/include/linux/mutex.h
+++ b/include/linux/mutex.h
@@ -20,6 +20,7 @@
#include <linux/osq_lock.h>
#include <linux/debug_locks.h>
#include <linux/cleanup.h>
+#include <linux/mutex_types.h>
#ifdef CONFIG_DEBUG_LOCK_ALLOC
# define __DEP_MAP_MUTEX_INITIALIZER(lockname) \
@@ -33,49 +34,6 @@
#ifndef CONFIG_PREEMPT_RT
-/*
- * Simple, straightforward mutexes with strict semantics:
- *
- * - only one task can hold the mutex at a time
- * - only the owner can unlock the mutex
- * - multiple unlocks are not permitted
- * - recursive locking is not permitted
- * - a mutex object must be initialized via the API
- * - a mutex object must not be initialized via memset or copying
- * - task may not exit with mutex held
- * - memory areas where held locks reside must not be freed
- * - held mutexes must not be reinitialized
- * - mutexes may not be used in hardware or software interrupt
- * contexts such as tasklets and timers
- *
- * These semantics are fully enforced when DEBUG_MUTEXES is
- * enabled. Furthermore, besides enforcing the above rules, the mutex
- * debugging code also implements a number of additional features
- * that make lock debugging easier and faster:
- *
- * - uses symbolic names of mutexes, whenever they are printed in debug output
- * - point-of-acquire tracking, symbolic lookup of function names
- * - list of all locks held in the system, printout of them
- * - owner tracking
- * - detects self-recursing locks and prints out all relevant info
- * - detects multi-task circular deadlocks and prints out all affected
- * locks and tasks (and only those tasks)
- */
-struct mutex {
- atomic_long_t owner;
- raw_spinlock_t wait_lock;
-#ifdef CONFIG_MUTEX_SPIN_ON_OWNER
- struct optimistic_spin_queue osq; /* Spinner MCS lock */
-#endif
- struct list_head wait_list;
-#ifdef CONFIG_DEBUG_MUTEXES
- void *magic;
-#endif
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
- struct lockdep_map dep_map;
-#endif
-};
-
#ifdef CONFIG_DEBUG_MUTEXES
#define __DEBUG_MUTEX_INITIALIZER(lockname) \
@@ -131,14 +89,6 @@ extern bool mutex_is_locked(struct mutex *lock);
/*
* Preempt-RT variant based on rtmutexes.
*/
-#include <linux/rtmutex.h>
Including rtmutex.h here means that mutex_types.h is no longer a simple
header for types only. So unless you also break out a rtmutex_types.h,
it is inconsistent.
Besides, the kernel/sched code does use mutex_lock/unlock calls quite
frequently. With this patch, mutex.h will not be directly included. I
suspect that it is indirectly included via other header files. This may
be an issue with some configurations.
Cheers, Longman