diff options
| author | Pan Xinhui <xinhui.pan@linux.vnet.ibm.com> | 2017-01-10 02:56:46 -0500 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2017-01-12 09:35:57 +0100 |
| commit | 75437bb304b20a2b350b9a8e9f9238d5e24e12ba (patch) | |
| tree | d8c179d3b1194a8eb7ce8ff9a0c5326dbcc0a01d | |
| parent | 607904c357c61adf20b8fd18af765e501d61a385 (diff) | |
locking/pvqspinlock: Don't wait if vCPU is preempted
If prev node is not in running state or its vCPU is preempted, we can give
up our vCPU slices in pv_wait_node() ASAP.
Signed-off-by: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: longman@redhat.com
Link: http://lkml.kernel.org/r/1484035006-6787-1-git-send-email-xinhui.pan@linux.vnet.ibm.com
[ Fixed typos in the changelog, removed ugly linebreak from the code. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
| -rw-r--r-- | kernel/locking/qspinlock_paravirt.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/locking/qspinlock_paravirt.h b/kernel/locking/qspinlock_paravirt.h index e3b5520005db..e6b2f7ad3e51 100644 --- a/kernel/locking/qspinlock_paravirt.h +++ b/kernel/locking/qspinlock_paravirt.h @@ -263,7 +263,7 @@ pv_wait_early(struct pv_node *prev, int loop) if ((loop & PV_PREV_CHECK_MASK) != 0) return false; - return READ_ONCE(prev->state) != vcpu_running; + return READ_ONCE(prev->state) != vcpu_running || vcpu_is_preempted(prev->cpu); } /* |