[PATCH 0/6] powerpc/qspinlock: Fix yield latency bug and other

Nicholas Piggin npiggin at gmail.com
Mon Oct 16 23:42:59 AEDT 2023

This fixes a long-standing latency bug in the powerpc qspinlock
implementation that quite a few people have reported and helped
out with debugging.

The first patch is a minimal fix that avoids the problem. The
other patches are streamlining and improvements after the fix.


Nicholas Piggin (6):
  powerpc/qspinlock: Fix stale propagated yield_cpu
  powerpc/qspinlock: stop queued waiters trying to set lock sleepy
  powerpc/qspinlock: propagate owner preemptedness rather than CPU
  powerpc/qspinlock: don't propagate the not-sleepy state
  powerpc/qspinlock: Propagate sleepy if previous waiter is preempted
  powerpc/qspinlock: Rename yield_propagate_owner tunable

 arch/powerpc/lib/qspinlock.c | 119 +++++++++++++++--------------------
 1 file changed, 52 insertions(+), 67 deletions(-)


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