speed up ReentrantLock by sinking try blocks (#32406)

base/lock.jl

@@ -40,19 +40,18 @@ Each successful `trylock` must be matched by an [`unlock`](@ref).
 function trylock(rl::ReentrantLock)
  t = current_task()
  lock(rl.cond_wait)
- try
- if rl.reentrancy_cnt == 0
- rl.locked_by = t
- rl.reentrancy_cnt = 1
- return true
- elseif t == notnothing(rl.locked_by)
- rl.reentrancy_cnt += 1
- return true
- end
- return false
- finally
- unlock(rl.cond_wait)
+ if rl.reentrancy_cnt == 0
+ rl.locked_by = t
+ rl.reentrancy_cnt = 1
+ got = true
+ elseif t === notnothing(rl.locked_by)
+ rl.reentrancy_cnt += 1
+ got = true
+ else
+ got = false
  end
+ unlock(rl.cond_wait)
+ return got
 end
 
 """
@@ -67,21 +66,24 @@ Each `lock` must be matched by an [`unlock`](@ref).
 function lock(rl::ReentrantLock)
  t = current_task()
  lock(rl.cond_wait)
- try
- while true
- if rl.reentrancy_cnt == 0
-  rl.locked_by = t
-  rl.reentrancy_cnt = 1
-  return
- elseif t == notnothing(rl.locked_by)
-  rl.reentrancy_cnt += 1
-  return
-  end
+ while true
+ if rl.reentrancy_cnt == 0
+ rl.locked_by = t
+ rl.reentrancy_cnt = 1
+ break
+ elseif t === notnothing(rl.locked_by)
+ rl.reentrancy_cnt += 1
+ break
+ end
+ try
  wait(rl.cond_wait)
+ catch
+ unlock(rl.cond_wait)
+ rethrow()
  end
- finally
- unlock(rl.cond_wait)
  end
+ unlock(rl.cond_wait)
+ return
 end
 
 """
@@ -95,33 +97,41 @@ internal counter and return immediately.
 function unlock(rl::ReentrantLock)
  t = current_task()
  rl.reentrancy_cnt == 0 && error("unlock count must match lock count")
- rl.locked_by == t || error("unlock from wrong thread")
+ rl.locked_by === t || error("unlock from wrong thread")
  lock(rl.cond_wait)
- try
- rl.reentrancy_cnt -= 1
- if rl.reentrancy_cnt == 0
- rl.locked_by = nothing
- notify(rl.cond_wait)
+ rl.reentrancy_cnt -= 1
+ if rl.reentrancy_cnt == 0
+ rl.locked_by = nothing
+ if !isempty(rl.cond_wait.waitq)
+ try
+ notify(rl.cond_wait)
+ catch
+ unlock(rl.cond_wait)
+ rethrow()
+ end
  end
- finally
- unlock(rl.cond_wait)
  end
+ unlock(rl.cond_wait)
  return
 end
 
 function unlockall(rl::ReentrantLock)
  t = current_task()
  n = rl.reentrancy_cnt
- rl.locked_by == t || error("unlock from wrong thread")
+ rl.locked_by === t || error("unlock from wrong thread")
  n == 0 && error("unlock count must match lock count")
  lock(rl.cond_wait)
- try
- rl.reentrancy_cnt = 0
- rl.locked_by = nothing
- notify(rl.cond_wait)
- finally
- unlock(rl.cond_wait)
+ rl.reentrancy_cnt = 0
+ rl.locked_by = nothing
+ if !isempty(rl.cond_wait.waitq)
+ try
+ notify(rl.cond_wait)
+ catch
+ unlock(rl.cond_wait)
+ rethrow()
+ end
  end
+ unlock(rl.cond_wait)
  return n
 end