search for: queue_spin_is_locked

...blic License for more details. + * + * (C) Copyright 2013-2014 Hewlett-Packard Development Company, L.P. + * + * Authors: Waiman Long <waiman.long at hp.com> + */ +#ifndef __ASM_GENERIC_QSPINLOCK_H +#define __ASM_GENERIC_QSPINLOCK_H + +#include <asm-generic/qspinlock_types.h> + +/** + * queue_spin_is_locked - is the spinlock locked? + * @lock: Pointer to queue spinlock structure + * Return: 1 if it is locked, 0 otherwise + */ +static __always_inline int queue_spin_is_locked(struct qspinlock *lock) +{ + return atomic_read(&lock->val); +} + +/** + * queue_spin_value_unlocked - is the spinlock str...

...blic License for more details. + * + * (C) Copyright 2013-2014 Hewlett-Packard Development Company, L.P. + * + * Authors: Waiman Long <waiman.long at hp.com> + */ +#ifndef __ASM_GENERIC_QSPINLOCK_H +#define __ASM_GENERIC_QSPINLOCK_H + +#include <asm-generic/qspinlock_types.h> + +/** + * queue_spin_is_locked - is the spinlock locked? + * @lock: Pointer to queue spinlock structure + * Return: 1 if it is locked, 0 otherwise + */ +static __always_inline int queue_spin_is_locked(struct qspinlock *lock) +{ + return atomic_read(&lock->val); +} + +/** + * queue_spin_value_unlocked - is the spinlock str...

...: Waiman Long <waiman.long at hp.com> + */ +#ifndef __ASM_GENERIC_QSPINLOCK_H +#define __ASM_GENERIC_QSPINLOCK_H + +#include <asm-generic/qspinlock_types.h> + +/* + * External function declarations + */ +extern void queue_spin_lock_slowpath(struct qspinlock *lock, int qsval); + +/** + * queue_spin_is_locked - is the spinlock locked? + * @lock: Pointer to queue spinlock structure + * Return: 1 if it is locked, 0 otherwise + */ +static __always_inline int queue_spin_is_locked(struct qspinlock *lock) +{ + return atomic_read(&lock->qlcode) & _QLOCK_LOCK_MASK; +} + +/** + * queue_spin_value_unlo...

...: Waiman Long <waiman.long at hp.com> + */ +#ifndef __ASM_GENERIC_QSPINLOCK_H +#define __ASM_GENERIC_QSPINLOCK_H + +#include <asm-generic/qspinlock_types.h> + +/* + * External function declarations + */ +extern void queue_spin_lock_slowpath(struct qspinlock *lock, int qsval); + +/** + * queue_spin_is_locked - is the spinlock locked? + * @lock: Pointer to queue spinlock structure + * Return: 1 if it is locked, 0 otherwise + */ +static __always_inline int queue_spin_is_locked(struct qspinlock *lock) +{ + return atomic_read(&lock->qlcode) & _QSPINLOCK_LOCKED; +} + +/** + * queue_spin_value_unl...

...: Waiman Long <waiman.long at hp.com> + */ +#ifndef __ASM_GENERIC_QSPINLOCK_H +#define __ASM_GENERIC_QSPINLOCK_H + +#include <asm-generic/qspinlock_types.h> + +/* + * External function declarations + */ +extern void queue_spin_lock_slowpath(struct qspinlock *lock, int qsval); + +/** + * queue_spin_is_locked - is the spinlock locked? + * @lock: Pointer to queue spinlock structure + * Return: 1 if it is locked, 0 otherwise + */ +static __always_inline int queue_spin_is_locked(struct qspinlock *lock) +{ + return atomic_read(&lock->qlcode) & _QSPINLOCK_LOCKED; +} + +/** + * queue_spin_value_unl...

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

v7->v8: - Remove one unneeded atomic operation from the slowpath, thus improving performance. - Simplify some of the codes and add more comments. - Test for X86_FEATURE_HYPERVISOR CPU feature bit to enable/disable unfair lock. - Reduce unfair lock slowpath lock stealing frequency depending on its distance from the queue head. - Add performance data for IvyBridge-EX CPU.

v7->v8: - Remove one unneeded atomic operation from the slowpath, thus improving performance. - Simplify some of the codes and add more comments. - Test for X86_FEATURE_HYPERVISOR CPU feature bit to enable/disable unfair lock. - Reduce unfair lock slowpath lock stealing frequency depending on its distance from the queue head. - Add performance data for IvyBridge-EX CPU.

v11->v12: - Based on PeterZ's version of the qspinlock patch (https://lkml.org/lkml/2014/6/15/63). - Incorporated many of the review comments from Konrad Wilk and Paolo Bonzini. - The pvqspinlock code is largely from my previous version with PeterZ's way of going from queue tail to head and his idea of using callee saved calls to KVM and XEN codes. v10->v11: - Use a

v11->v12: - Based on PeterZ's version of the qspinlock patch (https://lkml.org/lkml/2014/6/15/63). - Incorporated many of the review comments from Konrad Wilk and Paolo Bonzini. - The pvqspinlock code is largely from my previous version with PeterZ's way of going from queue tail to head and his idea of using callee saved calls to KVM and XEN codes. v10->v11: - Use a

v13->v14: - Patches 1 & 2: Add queue_spin_unlock_wait() to accommodate commit 78bff1c86 from Oleg Nesterov. - Fix the system hang problem when using PV qspinlock in an over-committed guest due to a racing condition in the pv_set_head_in_tail() function. - Increase the MAYHALT_THRESHOLD from 10 to 1024. - Change kick_cpu into a regular function pointer instead of a

v13->v14: - Patches 1 & 2: Add queue_spin_unlock_wait() to accommodate commit 78bff1c86 from Oleg Nesterov. - Fix the system hang problem when using PV qspinlock in an over-committed guest due to a racing condition in the pv_set_head_in_tail() function. - Increase the MAYHALT_THRESHOLD from 10 to 1024. - Change kick_cpu into a regular function pointer instead of a

Hi Waiman, As promised; here is the paravirt stuff I did during the trip to BOS last week. All the !paravirt patches are more or less the same as before (the only real change is the copyright lines in the first patch). The paravirt stuff is 'simple' and KVM only -- the Xen code was a little more convoluted and I've no real way to test that but it should be stright fwd to make work.

Hi Waiman, As promised; here is the paravirt stuff I did during the trip to BOS last week. All the !paravirt patches are more or less the same as before (the only real change is the copyright lines in the first patch). The paravirt stuff is 'simple' and KVM only -- the Xen code was a little more convoluted and I've no real way to test that but it should be stright fwd to make work.

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

v12->v13: - Change patch 9 to generate separate versions of the queue_spin_lock_slowpath functions for bare metal and PV guest. This reduces the performance impact of the PV code on bare metal systems. v11->v12: - Based on PeterZ's version of the qspinlock patch (https://lkml.org/lkml/2014/6/15/63). - Incorporated many of the review comments from Konrad Wilk and Paolo

v12->v13: - Change patch 9 to generate separate versions of the queue_spin_lock_slowpath functions for bare metal and PV guest. This reduces the performance impact of the PV code on bare metal systems. v11->v12: - Based on PeterZ's version of the qspinlock patch (https://lkml.org/lkml/2014/6/15/63). - Incorporated many of the review comments from Konrad Wilk and Paolo

N.B. Sorry for the duplicate. This patch series were resent as the original one was rejected by the vger.kernel.org list server due to long header. There is no change in content. v7->v8: - Remove one unneeded atomic operation from the slowpath, thus improving performance. - Simplify some of the codes and add more comments. - Test for X86_FEATURE_HYPERVISOR CPU feature bit