Peter Zijlstra says:

"Lots of cleanups and preparation; highlights:
 
  - futex: Cleanup and remove runtime futex_cmpxchg detection
 
  - rtmutex: Some fixes for the PREEMPT_RT locking infrastructure
 
  - kcsan: Share owner_on_cpu() between mutex,rtmutex and rwsem and
    annotate the racy owner->on_cpu access *once*.
 
  - atomic64: Dead-Code-Elemination"
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Merge tag 'locking_core_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull locking updates from Borislav Petkov:
 "Lots of cleanups and preparation. Highlights:

   - futex: Cleanup and remove runtime futex_cmpxchg detection

   - rtmutex: Some fixes for the PREEMPT_RT locking infrastructure

   - kcsan: Share owner_on_cpu() between mutex,rtmutex and rwsem and
     annotate the racy owner->on_cpu access *once*.

   - atomic64: Dead-Code-Elemination"

[ Description above by Peter Zijlstra ]

* tag 'locking_core_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/atomic: atomic64: Remove unusable atomic ops
  futex: Fix additional regressions
  locking: Allow to include asm/spinlock_types.h from linux/spinlock_types_raw.h
  x86/mm: Include spinlock_t definition in pgtable.
  locking: Mark racy reads of owner->on_cpu
  locking: Make owner_on_cpu() into <linux/sched.h>
  lockdep/selftests: Adapt ww-tests for PREEMPT_RT
  lockdep/selftests: Skip the softirq related tests on PREEMPT_RT
  lockdep/selftests: Unbalanced migrate_disable() & rcu_read_lock().
  lockdep/selftests: Avoid using local_lock_{acquire|release}().
  lockdep: Remove softirq accounting on PREEMPT_RT.
  locking/rtmutex: Add rt_mutex_lock_nest_lock() and rt_mutex_lock_killable().
  locking/rtmutex: Squash self-deadlock check for ww_rt_mutex.
  locking: Remove rt_rwlock_is_contended().
  sched: Trigger warning if ->migration_disabled counter underflows.
  futex: Fix sparc32/m68k/nds32 build regression
  futex: Remove futex_cmpxchg detection
  futex: Ensure futex_atomic_cmpxchg_inatomic() is present
  kernel/locking: Use a pointer in ww_mutex_trylock().
This commit is contained in:
Linus Torvalds 2022-01-11 17:24:45 -08:00
commit daadb3bd0e
45 changed files with 240 additions and 225 deletions

View file

@ -19,7 +19,11 @@
#include <asm/sync.h>
#include <asm/war.h>
#define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \
#define arch_futex_atomic_op_inuser arch_futex_atomic_op_inuser
#define futex_atomic_cmpxchg_inatomic futex_atomic_cmpxchg_inatomic
#include <asm-generic/futex.h>
#define __futex_atomic_op(op, insn, ret, oldval, uaddr, oparg) \
{ \
if (cpu_has_llsc && IS_ENABLED(CONFIG_WAR_R10000_LLSC)) { \
__asm__ __volatile__( \
@ -80,8 +84,10 @@
: "0" (0), GCC_OFF_SMALL_ASM() (*uaddr), "Jr" (oparg), \
"i" (-EFAULT) \
: "memory"); \
} else \
ret = -ENOSYS; \
} else { \
/* fallback for non-SMP */ \
ret = futex_atomic_op_inuser_local(op, oparg, oval, uaddr); \
} \
}
static inline int
@ -94,23 +100,23 @@ arch_futex_atomic_op_inuser(int op, int oparg, int *oval, u32 __user *uaddr)
switch (op) {
case FUTEX_OP_SET:
__futex_atomic_op("move $1, %z5", ret, oldval, uaddr, oparg);
__futex_atomic_op(op, "move $1, %z5", ret, oldval, uaddr, oparg);
break;
case FUTEX_OP_ADD:
__futex_atomic_op("addu $1, %1, %z5",
__futex_atomic_op(op, "addu $1, %1, %z5",
ret, oldval, uaddr, oparg);
break;
case FUTEX_OP_OR:
__futex_atomic_op("or $1, %1, %z5",
__futex_atomic_op(op, "or $1, %1, %z5",
ret, oldval, uaddr, oparg);
break;
case FUTEX_OP_ANDN:
__futex_atomic_op("and $1, %1, %z5",
__futex_atomic_op(op, "and $1, %1, %z5",
ret, oldval, uaddr, ~oparg);
break;
case FUTEX_OP_XOR:
__futex_atomic_op("xor $1, %1, %z5",
__futex_atomic_op(op, "xor $1, %1, %z5",
ret, oldval, uaddr, oparg);
break;
default:
@ -193,8 +199,9 @@ futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
: GCC_OFF_SMALL_ASM() (*uaddr), "Jr" (oldval), "Jr" (newval),
"i" (-EFAULT)
: "memory");
} else
return -ENOSYS;
} else {
return futex_atomic_cmpxchg_inatomic_local(uval, uaddr, oldval, newval);
}
*uval = val;
return ret;