Merge tag 'header_cleanup-2024-01-10' of https://evilpiepirate.org/git/bcachefs

Pull header cleanups from Kent Overstreet:
 "The goal is to get sched.h down to a type only header, so the main
  thing happening in this patchset is splitting out various _types.h
  headers and dependency fixups, as well as moving some things out of
  sched.h to better locations.

  This is prep work for the memory allocation profiling patchset which
  adds new sched.h interdepencencies"

* tag 'header_cleanup-2024-01-10' of https://evilpiepirate.org/git/bcachefs: (51 commits)
  Kill sched.h dependency on rcupdate.h
  kill unnecessary thread_info.h include
  Kill unnecessary kernel.h include
  preempt.h: Kill dependency on list.h
  rseq: Split out rseq.h from sched.h
  LoongArch: signal.c: add header file to fix build error
  restart_block: Trim includes
  lockdep: move held_lock to lockdep_types.h
  sem: Split out sem_types.h
  uidgid: Split out uidgid_types.h
  seccomp: Split out seccomp_types.h
  refcount: Split out refcount_types.h
  uapi/linux/resource.h: fix include
  x86/signal: kill dependency on time.h
  syscall_user_dispatch.h: split out *_types.h
  mm_types_task.h: Trim dependencies
  Split out irqflags_types.h
  ipc: Kill bogus dependency on spinlock.h
  shm: Slim down dependencies
  workqueue: Split out workqueue_types.h
  ...

1 files changed, 2 insertions, 77 deletions

diff --git a/include/linux/seqlock.h b/include/linux/seqlock.h
index e92f9d5577ba..d90d8ee29d81 100644
--- a/include/linux/seqlock.h
+++ b/include/linux/seqlock.h
@@ -18,6 +18,7 @@
 #include <linux/lockdep.h>
 #include <linux/mutex.h>
 #include <linux/preempt.h>
+#include <linux/seqlock_types.h>
 #include <linux/spinlock.h>
 
 #include <asm/processor.h>
@@ -37,37 +38,6 @@
  */
 #define KCSAN_SEQLOCK_REGION_MAX 1000
 
-/*
- * Sequence counters (seqcount_t)
- *
- * This is the raw counting mechanism, without any writer protection.
- *
- * Write side critical sections must be serialized and non-preemptible.
- *
- * If readers can be invoked from hardirq or softirq contexts,
- * interrupts or bottom halves must also be respectively disabled before
- * entering the write section.
- *
- * This mechanism can't be used if the protected data contains pointers,
- * as the writer can invalidate a pointer that a reader is following.
- *
- * If the write serialization mechanism is one of the common kernel
- * locking primitives, use a sequence counter with associated lock
- * (seqcount_LOCKNAME_t) instead.
- *
- * If it's desired to automatically handle the sequence counter writer
- * serialization and non-preemptibility requirements, use a sequential
- * lock (seqlock_t) instead.
- *
- * See Documentation/locking/seqlock.rst
- */
-typedef struct seqcount {
-	unsigned sequence;
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
-	struct lockdep_map dep_map;
-#endif
-} seqcount_t;
-
 static inline void __seqcount_init(seqcount_t *s, const char *name,
 					  struct lock_class_key *key)
 {
@@ -132,28 +102,6 @@ static inline void seqcount_lockdep_reader_access(const seqcount_t *s)
  */
 
 /*
- * For PREEMPT_RT, seqcount_LOCKNAME_t write side critical sections cannot
- * disable preemption. It can lead to higher latencies, and the write side
- * sections will not be able to acquire locks which become sleeping locks
- * (e.g. spinlock_t).
- *
- * To remain preemptible while avoiding a possible livelock caused by the
- * reader preempting the writer, use a different technique: let the reader
- * detect if a seqcount_LOCKNAME_t writer is in progress. If that is the
- * case, acquire then release the associated LOCKNAME writer serialization
- * lock. This will allow any possibly-preempted writer to make progress
- * until the end of its writer serialization lock critical section.
- *
- * This lock-unlock technique must be implemented for all of PREEMPT_RT
- * sleeping locks.  See Documentation/locking/locktypes.rst
- */
-#if defined(CONFIG_LOCKDEP) || defined(CONFIG_PREEMPT_RT)
-#define __SEQ_LOCK(expr)	expr
-#else
-#define __SEQ_LOCK(expr)
-#endif
-
-/*
  * typedef seqcount_LOCKNAME_t - sequence counter with LOCKNAME associated
  * @seqcount:	The real sequence counter
  * @lock:	Pointer to the associated lock
@@ -194,11 +142,6 @@ static inline void seqcount_lockdep_reader_access(const seqcount_t *s)
  * @lockbase:		prefix for associated lock/unlock
  */
 #define SEQCOUNT_LOCKNAME(lockname, locktype, preemptible, lockbase)	\
-typedef struct seqcount_##lockname {					\
-	seqcount_t		seqcount;				\
-	__SEQ_LOCK(locktype	*lock);					\
-} seqcount_##lockname##_t;						\
-									\
 static __always_inline seqcount_t *					\
 __seqprop_##lockname##_ptr(seqcount_##lockname##_t *s)			\
 {									\
@@ -284,6 +227,7 @@ SEQCOUNT_LOCKNAME(raw_spinlock, raw_spinlock_t,  false,    raw_spin)
 SEQCOUNT_LOCKNAME(spinlock,     spinlock_t,      __SEQ_RT, spin)
 SEQCOUNT_LOCKNAME(rwlock,       rwlock_t,        __SEQ_RT, read)
 SEQCOUNT_LOCKNAME(mutex,        struct mutex,    true,     mutex)
+#undef SEQCOUNT_LOCKNAME
 
 /*
  * SEQCNT_LOCKNAME_ZERO - static initializer for seqcount_LOCKNAME_t
@@ -794,25 +738,6 @@ static inline void raw_write_seqcount_latch(seqcount_latch_t *s)
 	smp_wmb();      /* increment "sequence" before following stores */
 }
 
-/*
- * Sequential locks (seqlock_t)
- *
- * Sequence counters with an embedded spinlock for writer serialization
- * and non-preemptibility.
- *
- * For more info, see:
- *    - Comments on top of seqcount_t
- *    - Documentation/locking/seqlock.rst
- */
-typedef struct {
-	/*
-	 * Make sure that readers don't starve writers on PREEMPT_RT: use
-	 * seqcount_spinlock_t instead of seqcount_t. Check __SEQ_LOCK().
-	 */
-	seqcount_spinlock_t seqcount;
-	spinlock_t lock;
-} seqlock_t;
-
 #define __SEQLOCK_UNLOCKED(lockname)					\
 	{								\
 		.seqcount = SEQCNT_SPINLOCK_ZERO(lockname, &(lockname).lock), \