search for: pv_set_vars

...void +pv_next_node_check(struct pv_qvars *pv, struct qspinlock *lock) +{ + if (!static_key_false(&paravirt_spinlocks_enabled)) + return; + if (ACCESS_ONCE(pv->cpustate) == PV_CPU_HALTED) + ACCESS_ONCE(((union arch_qspinlock *)lock)->lock) + = _QSPINLOCK_LOCKED_SLOWPATH; +} + +/** + * pv_set_vars - set nxtcpu_p1 in previous PV and prev in current PV + * @pv : pointer to struct pv_qvars + * @ppv : pointer to struct pv_qvars of previous node + * @cpu : cpu number + * @prev: pointer to the previous queue node + */ +static __always_inline void pv_set_vars(struct pv_qvars *pv, + struct pv_qva...

This patch adds para-virtualization support to the queue spinlock code by enabling the queue head to kick the lock holder CPU, if known, in when the lock isn't released for a certain amount of time. It also enables the mutual monitoring of the queue head CPU and the following node CPU in the queue to make sure that their CPUs will stay scheduled in. Signed-off-by: Waiman Long <Waiman.Long

v5->v6: - Change the optimized 2-task contending code to make it fairer at the expense of a bit of performance. - Add a patch to support unfair queue spinlock for Xen. - Modify the PV qspinlock code to follow what was done in the PV ticketlock. - Add performance data for the unfair lock as well as the PV support code. v4->v5: - Move the optimized 2-task contending code to the

v5->v6: - Change the optimized 2-task contending code to make it fairer at the expense of a bit of performance. - Add a patch to support unfair queue spinlock for Xen. - Modify the PV qspinlock code to follow what was done in the PV ticketlock. - Add performance data for the unfair lock as well as the PV support code. v4->v5: - Move the optimized 2-task contending code to the

v4->v5: - Move the optimized 2-task contending code to the generic file to enable more architectures to use it without code duplication. - Address some of the style-related comments by PeterZ. - Allow the use of unfair queue spinlock in a real para-virtualized execution environment. - Add para-virtualization support to the qspinlock code by ensuring that the lock holder and queue

v4->v5: - Move the optimized 2-task contending code to the generic file to enable more architectures to use it without code duplication. - Address some of the style-related comments by PeterZ. - Allow the use of unfair queue spinlock in a real para-virtualized execution environment. - Add para-virtualization support to the qspinlock code by ensuring that the lock holder and queue

v4->v5: - Move the optimized 2-task contending code to the generic file to enable more architectures to use it without code duplication. - Address some of the style-related comments by PeterZ. - Allow the use of unfair queue spinlock in a real para-virtualized execution environment. - Add para-virtualization support to the qspinlock code by ensuring that the lock holder and queue

v4->v5: - Move the optimized 2-task contending code to the generic file to enable more architectures to use it without code duplication. - Address some of the style-related comments by PeterZ. - Allow the use of unfair queue spinlock in a real para-virtualized execution environment. - Add para-virtualization support to the qspinlock code by ensuring that the lock holder and queue

v6->v7: - Remove an atomic operation from the 2-task contending code - Shorten the names of some macros - Make the queue waiter to attempt to steal lock when unfair lock is enabled. - Remove lock holder kick from the PV code and fix a race condition - Run the unfair lock & PV code on overcommitted KVM guests to collect performance data. v5->v6: - Change the optimized

v6->v7: - Remove an atomic operation from the 2-task contending code - Shorten the names of some macros - Make the queue waiter to attempt to steal lock when unfair lock is enabled. - Remove lock holder kick from the PV code and fix a race condition - Run the unfair lock & PV code on overcommitted KVM guests to collect performance data. v5->v6: - Change the optimized