From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Wed, 27 Nov 2019 00:02:40 +0000 (-0800)
Subject: Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel... 
X-Git-Tag: v5.5-rc1~149
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=168829ad09ca9cdfdc664b2110d0e3569932c12d;p=users%2Fjedix%2Flinux-maple.git

Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull locking updates from Ingo Molnar:
 "The main changes in this cycle were:

   - A comprehensive rewrite of the robust/PI futex code's exit handling
     to fix various exit races. (Thomas Gleixner et al)

   - Rework the generic REFCOUNT_FULL implementation using
     atomic_fetch_* operations so that the performance impact of the
     cmpxchg() loops is mitigated for common refcount operations.

     With these performance improvements the generic implementation of
     refcount_t should be good enough for everybody - and this got
     confirmed by performance testing, so remove ARCH_HAS_REFCOUNT and
     REFCOUNT_FULL entirely, leaving the generic implementation enabled
     unconditionally. (Will Deacon)

   - Other misc changes, fixes, cleanups"

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (27 commits)
  lkdtm: Remove references to CONFIG_REFCOUNT_FULL
  locking/refcount: Remove unused 'refcount_error_report()' function
  locking/refcount: Consolidate implementations of refcount_t
  locking/refcount: Consolidate REFCOUNT_{MAX,SATURATED} definitions
  locking/refcount: Move saturation warnings out of line
  locking/refcount: Improve performance of generic REFCOUNT_FULL code
  locking/refcount: Move the bulk of the REFCOUNT_FULL implementation into the <linux/refcount.h> header
  locking/refcount: Remove unused refcount_*_checked() variants
  locking/refcount: Ensure integer operands are treated as signed
  locking/refcount: Define constants for saturation and max refcount values
  futex: Prevent exit livelock
  futex: Provide distinct return value when owner is exiting
  futex: Add mutex around futex exit
  futex: Provide state handling for exec() as well
  futex: Sanitize exit state handling
  futex: Mark the begin of futex exit explicitly
  futex: Set task::futex_state to DEAD right after handling futex exit
  futex: Split futex_mm_release() for exit/exec
  exit/exec: Seperate mm_release()
  futex: Replace PF_EXITPIDONE with a state
  ...
---

168829ad09ca9cdfdc664b2110d0e3569932c12d
diff --cc net/core/sock.c
index 71787f7c4f8c,50b930364cb0..043db3ce023e
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@@ -518,8 -521,8 +518,8 @@@ int __sk_receive_skb(struct sock *sk, s
  
  		rc = sk_backlog_rcv(sk, skb);
  
- 		mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
+ 		mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
 -	} else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) {
 +	} else if (sk_add_backlog(sk, skb, READ_ONCE(sk->sk_rcvbuf))) {
  		bh_unlock_sock(sk);
  		atomic_inc(&sk->sk_drops);
  		goto discard_and_relse;