Thread (5 messages) 5 messages, 2 authors, 2017-10-02

Re: [PATCH v3 0/2] guard virt_spin_lock() with a static key

From: Juergen Gross <jgross@suse.com>
Date: 2017-09-25 13:59:14

Ping?

On 06/09/17 19:36, Juergen Gross wrote:
With virt_spin_lock() being guarded by a static key the bare metal case
can be optimized by patching the call away completely. In case a kernel
running as a guest it can decide whether to use paravitualized
spinlocks, the current fallback to the unfair test-and-set scheme, or
to mimic the bare metal behavior.

V3:
- remove test for hypervisor environment from virt_spin_lock(9 as
  suggested by Waiman Long

V2:
- use static key instead of making virt_spin_lock() a pvops function

Juergen Gross (2):
  paravirt/locks: use new static key for controlling call of
    virt_spin_lock()
  paravirt,xen: correct xen_nopvspin case

 arch/x86/include/asm/qspinlock.h     | 11 ++++++++++-
 arch/x86/kernel/paravirt-spinlocks.c |  6 ++++++
 arch/x86/kernel/smpboot.c            |  2 ++
 arch/x86/xen/spinlock.c              |  2 ++
 kernel/locking/qspinlock.c           |  4 ++++
 5 files changed, 24 insertions(+), 1 deletion(-)
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