search for: zero_stats

On 15/02/15 17:30, Raghavendra K T wrote: > --- a/arch/x86/xen/spinlock.c > +++ b/arch/x86/xen/spinlock.c > @@ -41,7 +41,7 @@ static u8 zero_stats; > static inline void check_zero(void) > { > u8 ret; > - u8 old = ACCESS_ONCE(zero_stats); > + u8 old = READ_ONCE(zero_stats); > if (unlikely(old)) { > ret = cmpxchg(&zero_stats, old, 0); > /* This ensures only one fellow resets the stat */ > @@ -112,6 +11...

On 15/02/15 17:30, Raghavendra K T wrote: > --- a/arch/x86/xen/spinlock.c > +++ b/arch/x86/xen/spinlock.c > @@ -41,7 +41,7 @@ static u8 zero_stats; > static inline void check_zero(void) > { > u8 ret; > - u8 old = ACCESS_ONCE(zero_stats); > + u8 old = READ_ONCE(zero_stats); > if (unlikely(old)) { > ret = cmpxchg(&zero_stats, old, 0); > /* This ensures only one fellow resets the stat */ > @@ -112,6 +11...

...kets_equal(tmp.head, head)) break; cpu_relax(); diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index 94f6434..9c6c8cf 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -609,7 +609,7 @@ static inline void check_zero(void) u8 ret; u8 old; - old = ACCESS_ONCE(zero_stats); + old = READ_ONCE(zero_stats); if (unlikely(old)) { ret = cmpxchg(&zero_stats, old, 0); /* This ensures only one fellow resets the stat */ @@ -727,6 +727,7 @@ __visible void kvm_lock_spinning(struct arch_spinlock *lock, __ticket_t want) int cpu; u64 start; unsigned long flags; +...

...kets_equal(tmp.head, head)) break; cpu_relax(); diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index 94f6434..9c6c8cf 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -609,7 +609,7 @@ static inline void check_zero(void) u8 ret; u8 old; - old = ACCESS_ONCE(zero_stats); + old = READ_ONCE(zero_stats); if (unlikely(old)) { ret = cmpxchg(&zero_stats, old, 0); /* This ensures only one fellow resets the stat */ @@ -727,6 +727,7 @@ __visible void kvm_lock_spinning(struct arch_spinlock *lock, __ticket_t want) int cpu; u64 start; unsigned long flags; +...

...kets_equal(tmp.head, head)) break; cpu_relax(); diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index 94f6434..e354cc6 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -609,7 +609,7 @@ static inline void check_zero(void) u8 ret; u8 old; - old = ACCESS_ONCE(zero_stats); + old = READ_ONCE(zero_stats); if (unlikely(old)) { ret = cmpxchg(&zero_stats, old, 0); /* This ensures only one fellow resets the stat */ @@ -727,6 +727,7 @@ __visible void kvm_lock_spinning(struct arch_spinlock *lock, __ticket_t want) int cpu; u64 start; unsigned long flags; +...

...kets_equal(tmp.head, head)) break; cpu_relax(); diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index 94f6434..e354cc6 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -609,7 +609,7 @@ static inline void check_zero(void) u8 ret; u8 old; - old = ACCESS_ONCE(zero_stats); + old = READ_ONCE(zero_stats); if (unlikely(old)) { ret = cmpxchg(&zero_stats, old, 0); /* This ensures only one fellow resets the stat */ @@ -727,6 +727,7 @@ __visible void kvm_lock_spinning(struct arch_spinlock *lock, __ticket_t want) int cpu; u64 start; unsigned long flags; +...

...kets_equal(tmp.head, head)) break; cpu_relax(); diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index 94f6434..9c6c8cf 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -609,7 +609,7 @@ static inline void check_zero(void) u8 ret; u8 old; - old = ACCESS_ONCE(zero_stats); + old = READ_ONCE(zero_stats); if (unlikely(old)) { ret = cmpxchg(&zero_stats, old, 0); /* This ensures only one fellow resets the stat */ @@ -727,6 +727,7 @@ __visible void kvm_lock_spinning(struct arch_spinlock *lock, __ticket_t want) int cpu; u64 start; unsigned long flags; +...

...kets_equal(tmp.head, head)) break; cpu_relax(); diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index 94f6434..9c6c8cf 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -609,7 +609,7 @@ static inline void check_zero(void) u8 ret; u8 old; - old = ACCESS_ONCE(zero_stats); + old = READ_ONCE(zero_stats); if (unlikely(old)) { ret = cmpxchg(&zero_stats, old, 0); /* This ensures only one fellow resets the stat */ @@ -727,6 +727,7 @@ __visible void kvm_lock_spinning(struct arch_spinlock *lock, __ticket_t want) int cpu; u64 start; unsigned long flags; +...

The 5-patch series to follow this email extends KVM-hypervisor and Linux guest running on KVM-hypervisor to support pv-ticket spinlocks, based on Xen's implementation. One hypercall is introduced in KVM hypervisor,that allows a vcpu to kick another vcpu out of halt state. The blocking of vcpu is done using halt() in (lock_spinning) slowpath. Changes in V4: - reabsed to 3.2.0 pre. - use APIC

The 5-patch series to follow this email extends KVM-hypervisor and Linux guest running on KVM-hypervisor to support pv-ticket spinlocks, based on Xen's implementation. One hypercall is introduced in KVM hypervisor,that allows a vcpu to kick another vcpu out of halt state. The blocking of vcpu is done using halt() in (lock_spinning) slowpath. Changes in V4: - reabsed to 3.2.0 pre. - use APIC

...pinning = PV_CALLEE_SAVE(xen_lock_spinning); pv_lock_ops.unlock_kick = xen_unlock_kick; +#endif } /* @@ -318,6 +414,7 @@ static int __init xen_spinlock_debugfs(void) d_spin_debug = debugfs_create_dir("spinlocks", d_xen); +#ifndef CONFIG_QUEUE_SPINLOCK debugfs_create_u8("zero_stats", 0644, d_spin_debug, &zero_stats); debugfs_create_u32("taken_slow", 0444, d_spin_debug, @@ -337,7 +434,19 @@ static int __init xen_spinlock_debugfs(void) debugfs_create_u32_array("histo_blocked", 0444, d_spin_debug, spinlock_stats.histo_spin_blocked, HISTO...

...pinning = PV_CALLEE_SAVE(xen_lock_spinning); pv_lock_ops.unlock_kick = xen_unlock_kick; +#endif } /* @@ -321,6 +444,7 @@ static int __init xen_spinlock_debugfs(void) d_spin_debug = debugfs_create_dir("spinlocks", d_xen); +#ifndef CONFIG_QUEUE_SPINLOCK debugfs_create_u8("zero_stats", 0644, d_spin_debug, &zero_stats); debugfs_create_u32("taken_slow", 0444, d_spin_debug, @@ -340,7 +464,22 @@ static int __init xen_spinlock_debugfs(void) debugfs_create_u32_array("histo_blocked", 0444, d_spin_debug, spinlock_stats.histo_spin_blocked, HISTO...

...pinning = PV_CALLEE_SAVE(xen_lock_spinning); pv_lock_ops.unlock_kick = xen_unlock_kick; +#endif } /* @@ -321,6 +444,7 @@ static int __init xen_spinlock_debugfs(void) d_spin_debug = debugfs_create_dir("spinlocks", d_xen); +#ifndef CONFIG_QUEUE_SPINLOCK debugfs_create_u8("zero_stats", 0644, d_spin_debug, &zero_stats); debugfs_create_u32("taken_slow", 0444, d_spin_debug, @@ -340,7 +464,22 @@ static int __init xen_spinlock_debugfs(void) debugfs_create_u32_array("histo_blocked", 0444, d_spin_debug, spinlock_stats.histo_spin_blocked, HISTO...

The 4-patch series to follow this email extends KVM-hypervisor and Linux guest running on KVM-hypervisor to support pv-ticket spinlocks, based on Xen's implementation. One hypercall is introduced in KVM hypervisor,that allows a vcpu to kick another vcpu out of halt state. The blocking of vcpu is done using halt() in (lock_spinning) slowpath. The V2 change discussion was in:

The 4-patch series to follow this email extends KVM-hypervisor and Linux guest running on KVM-hypervisor to support pv-ticket spinlocks, based on Xen's implementation. One hypercall is introduced in KVM hypervisor,that allows a vcpu to kick another vcpu out of halt state. The blocking of vcpu is done using halt() in (lock_spinning) slowpath. The V2 change discussion was in:

This series replaces the existing paravirtualized spinlock mechanism with a paravirtualized ticketlock mechanism. The series provides implementation for both Xen and KVM. The current set of patches are for Xen/x86 spinlock/KVM guest side, to be included against -tip. I 'll be sending a separate patchset for KVM host based on kvm tree. Please note I have added the below performance result

This series replaces the existing paravirtualized spinlock mechanism with a paravirtualized ticketlock mechanism. The series provides implementation for both Xen and KVM. The current set of patches are for Xen/x86 spinlock/KVM guest side, to be included against -tip. I 'll be sending a separate patchset for KVM host based on kvm tree. Please note I have added the below performance result

This series replaces the existing paravirtualized spinlock mechanism with a paravirtualized ticketlock mechanism. The series provides implementation for both Xen and KVM. The current set of patches are for Xen/x86 spinlock/KVM guest side, to be included against -tip. I 'll be sending a separate patchset for KVM host based on kvm tree. Please note I have added the below performance result

The 5-patch series to follow this email extends KVM-hypervisor and Linux guest running on KVM-hypervisor to support pv-ticket spinlocks, based on Xen's implementation. One hypercall is introduced in KVM hypervisor,that allows a vcpu to kick another vcpu out of halt state. The blocking of vcpu is done using halt() in (lock_spinning) slowpath. Note: 1) patch is based on 3.4-rc3 + ticketlock

The 5-patch series to follow this email extends KVM-hypervisor and Linux guest running on KVM-hypervisor to support pv-ticket spinlocks, based on Xen's implementation. One hypercall is introduced in KVM hypervisor,that allows a vcpu to kick another vcpu out of halt state. The blocking of vcpu is done using halt() in (lock_spinning) slowpath. Note: 1) patch is based on 3.4-rc3 + ticketlock