search for: unfair_locks_init_jump

...f CONFIG_VIRT_UNFAIR_LOCKS +struct static_key virt_unfairlocks_enabled = STATIC_KEY_INIT_FALSE; +EXPORT_SYMBOL(virt_unfairlocks_enabled); + +#include <linux/init.h> +#include <asm/cpufeature.h> + +/* + * Enable unfair lock only if it is running under a hypervisor + */ +static __init int unfair_locks_init_jump(void) +{ + if (!boot_cpu_has(X86_FEATURE_HYPERVISOR)) + return 0; + + static_key_slow_inc(&virt_unfairlocks_enabled); + printk(KERN_INFO "Unfair spinlock enabled\n"); + + return 0; +} +early_initcall(unfair_locks_init_jump); + +#endif diff --git a/kernel/locking/qspinlock.c b/kernel/...

...AVIRT_UNFAIR_LOCKS +struct static_key paravirt_unfairlocks_enabled = STATIC_KEY_INIT_FALSE; +EXPORT_SYMBOL(paravirt_unfairlocks_enabled); + +#include <linux/init.h> +#include <asm/cpufeature.h> + +/* + * Enable unfair lock only if it is running under a hypervisor + */ +static __init int unfair_locks_init_jump(void) +{ + if (!boot_cpu_has(X86_FEATURE_HYPERVISOR)) + return 0; + + static_key_slow_inc(&paravirt_unfairlocks_enabled); + printk(KERN_INFO "Unfair spinlock enabled\n"); + + return 0; +} +early_initcall(unfair_locks_init_jump); + +#endif diff --git a/kernel/locking/qspinlock.c b/ker...

v10->v11: - Use a simple test-and-set unfair lock to simplify the code, but performance may suffer a bit for large guest with many CPUs. - Take out Raghavendra KT's test results as the unfair lock changes may render some of his results invalid. - Add PV support without increasing the size of the core queue node structure. - Other minor changes to address some of the

v10->v11: - Use a simple test-and-set unfair lock to simplify the code, but performance may suffer a bit for large guest with many CPUs. - Take out Raghavendra KT's test results as the unfair lock changes may render some of his results invalid. - Add PV support without increasing the size of the core queue node structure. - Other minor changes to address some of the

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.

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

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

v8->v9: - Integrate PeterZ's version of the queue spinlock patch with some modification: http://lkml.kernel.org/r/20140310154236.038181843 at infradead.org - Break the more complex patches into smaller ones to ease review effort. - Fix a racing condition in the PV qspinlock code. v7->v8: - Remove one unneeded atomic operation from the slowpath, thus improving

v8->v9: - Integrate PeterZ's version of the queue spinlock patch with some modification: http://lkml.kernel.org/r/20140310154236.038181843 at infradead.org - Break the more complex patches into smaller ones to ease review effort. - Fix a racing condition in the PV qspinlock code. v7->v8: - Remove one unneeded atomic operation from the slowpath, thus improving

v9->v10: - Make some minor changes to qspinlock.c to accommodate review feedback. - Change author to PeterZ for 2 of the patches. - Include Raghavendra KT's test results in patch 18. v8->v9: - Integrate PeterZ's version of the queue spinlock patch with some modification: http://lkml.kernel.org/r/20140310154236.038181843 at infradead.org - Break the more complex

v9->v10: - Make some minor changes to qspinlock.c to accommodate review feedback. - Change author to PeterZ for 2 of the patches. - Include Raghavendra KT's test results in patch 18. v8->v9: - Integrate PeterZ's version of the queue spinlock patch with some modification: http://lkml.kernel.org/r/20140310154236.038181843 at infradead.org - Break the more complex