search for: atomic_inc

...m not mad keen on propagating these sorts of asm atomic operations throughout > our code base. Other options would be: gcc has atomic builtins to do this kind of work. I don''t know about arm, but they do the job in x86 http://gcc.gnu.org/onlinedocs/gcc-4.1.1/gcc/Atomic-Builtins.html so atomic_inc(val) -> __sync_fetch_and_add(val, 1) and likewise for dec/sub Andres > > - use libatomic-ops, http://www.hpl.hp.com/research/linux/atomic_ops/, although > this doesn''t seem to be as widespread as I would like (not in RHEL5 for > example) > - use a pthread lock. This...

...HV_TEST_DEV_SINT_ROUTE_SET_SINT +}; + +static atomic_t isr_enter_count[MAX_CPUS]; +static atomic_t cpus_comp_count; + +static bool synic_supported(void) +{ + return cpuid(HYPERV_CPUID_FEATURES).a & HV_X64_MSR_SYNIC_AVAILABLE; +} + +static void synic_sint_auto_eoi_isr(isr_regs_t *regs) +{ + atomic_inc(&isr_enter_count[smp_id()]); +} + +static void synic_sint_isr(isr_regs_t *regs) +{ + atomic_inc(&isr_enter_count[smp_id()]); + eoi(); +} + +static void synic_ctl(u8 ctl, u8 vcpu_id, u8 sint) +{ + outl((ctl << 16)|((vcpu_id) << 8)|sint, 0x3000); +} + +struct sint_vec_ent...

...HV_TEST_DEV_SINT_ROUTE_SET_SINT +}; + +static atomic_t isr_enter_count[MAX_CPUS]; +static atomic_t cpus_comp_count; + +static bool synic_supported(void) +{ + return cpuid(HYPERV_CPUID_FEATURES).a & HV_X64_MSR_SYNIC_AVAILABLE; +} + +static void synic_sint_auto_eoi_isr(isr_regs_t *regs) +{ + atomic_inc(&isr_enter_count[smp_id()]); +} + +static void synic_sint_isr(isr_regs_t *regs) +{ + atomic_inc(&isr_enter_count[smp_id()]); + eoi(); +} + +static void synic_ctl(u8 ctl, u8 vcpu_id, u8 sint) +{ + outl((ctl << 16)|((vcpu_id) << 8)|sint, 0x3000); +} + +struct sint_vec_ent...

...iocb, struct file *file = iocb->ki_filp; struct inode *inode = file->f_mapping->host; int flags = 0; - bool wakeup = false; + bool wakeup = true; int ret; if (check_direct_IO(BTRFS_I(inode)->root, rw, iocb, iov, offset, nr_segs)) return 0; - if (rw == READ) { - atomic_inc(&inode->i_dio_count); - smp_mb__after_atomic_inc(); - if (unlikely(test_bit(BTRFS_INODE_READDIO_NEED_LOCK, - &BTRFS_I(inode)->runtime_flags))) { - inode_dio_done(inode); - flags = DIO_LOCKING | DIO_SKIP_HOLES; - } else { - wakeup = true; - } + atomic_inc(&inode-...

...secondary mmu by calling * mmu_notifier_invalidate_range() see comments below inside @@ -2117,30 +2117,34 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, pte = pte_offset_map(&_pmd, addr); BUG_ON(!pte_none(*pte)); set_pte_at(mm, addr, pte, entry); - atomic_inc(&page[i]._mapcount); - pte_unmap(pte); - } - - /* - * Set PG_double_map before dropping compound_mapcount to avoid - * false-negative page_mapped(). - */ - if (compound_mapcount(page) > 1 && !TestSetPageDoubleMap(page)) { - for (i = 0; i < HPAGE_PMD_NR; i++) + if (!pmd_migra...

...ic_t isr_enter_count[MAX_CPUS]; > +static atomic_t cpus_comp_count; > + > +static bool synic_supported(void) > +{ > + return cpuid(HYPERV_CPUID_FEATURES).a & HV_X64_MSR_SYNIC_AVAILABLE; > +} > + > +static void synic_sint_auto_eoi_isr(isr_regs_t *regs) > +{ > + atomic_inc(&isr_enter_count[smp_id()]); > +} > + > +static void synic_sint_isr(isr_regs_t *regs) > +{ > + atomic_inc(&isr_enter_count[smp_id()]); > + eoi(); > +} > + > +static void synic_ctl(u8 ctl, u8 vcpu_id, u8 sint) > +{ > + outl((ctl << 16)|((vcpu_i...

...point. Later they were dropped or converted to regular ints protected by a mutex. The commit that made these changes left an unused smp_mb__after_atomic() in vhost_scsi_set_endpoint(). It was previously used after incrementing vhost_scsi->vhost_ref_cnt but this field has been dropped: - atomic_inc(&vs->vhost_ref_cnt); smp_mb__after_atomic_inc(); Reported-by: Andrea Parri <andrea.parri at amarulasolutions.com> Fixes: 101998f6fcd680 ("tcm_vhost: Post-merge review changes requested by MST") Signed-off-by: Stefan Hajnoczi <stefanha at redhat.com> --- driver...

...point. Later they were dropped or converted to regular ints protected by a mutex. The commit that made these changes left an unused smp_mb__after_atomic() in vhost_scsi_set_endpoint(). It was previously used after incrementing vhost_scsi->vhost_ref_cnt but this field has been dropped: - atomic_inc(&vs->vhost_ref_cnt); smp_mb__after_atomic_inc(); Reported-by: Andrea Parri <andrea.parri at amarulasolutions.com> Fixes: 101998f6fcd680 ("tcm_vhost: Post-merge review changes requested by MST") Signed-off-by: Stefan Hajnoczi <stefanha at redhat.com> --- driver...

...ruct storvsc_device *)Device->Extension; + + spin_lock_irqsave(&storDevice->lock, flags); + + if (storDevice->reset == 1) { + spin_unlock_irqrestore(&storDevice->lock, flags); + return NULL; + } + if (storDevice && atomic_read(&storDevice->RefCount) > 1) atomic_inc(&storDevice->RefCount); else storDevice = NULL; + spin_unlock_irqrestore(&storDevice->lock, flags); + return storDevice; } @@ -122,13 +139,19 @@ static inline struct storvsc_device *GetStorDevice(struct hv_device *Device) static inline struct storvsc_device *MustGetStorDe...

...ruct storvsc_device *)Device->Extension; + + spin_lock_irqsave(&storDevice->lock, flags); + + if (storDevice->reset == 1) { + spin_unlock_irqrestore(&storDevice->lock, flags); + return NULL; + } + if (storDevice && atomic_read(&storDevice->RefCount) > 1) atomic_inc(&storDevice->RefCount); else storDevice = NULL; + spin_unlock_irqrestore(&storDevice->lock, flags); + return storDevice; } @@ -122,13 +139,19 @@ static inline struct storvsc_device *GetStorDevice(struct hv_device *Device) static inline struct storvsc_device *MustGetStorDe...

...worker = list_entry(fallback, 601 struct btrfs_worker_thread, worker_list); 602 found: 603 /* 604 * this makes sure the worker doesn''t exit before it is placed 605 * onto a busy/idle list 606 */ 607 atomic_inc(&worker->num_pending); 608 spin_unlock_irqrestore(&workers->lock, flags); ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ And again here. Btw, does find_worker() ever get called with IRQs disabled? If so then __btrfs_start_workers() enables them. Maybe that functi...

...* mmu_notifier_invalidate_range() see comments below inside > @@ -2117,30 +2117,34 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, > pte = pte_offset_map(&_pmd, addr); > BUG_ON(!pte_none(*pte)); > set_pte_at(mm, addr, pte, entry); > - atomic_inc(&page[i]._mapcount); > - pte_unmap(pte); > - } > - > - /* > - * Set PG_double_map before dropping compound_mapcount to avoid > - * false-negative page_mapped(). > - */ > - if (compound_mapcount(page) > 1 && !TestSetPageDoubleMap(page)) { > - for (i = 0...

...> +{ > + return atomic_read(&vmci_host_active_users); > +} > + > /* > * Called on open of /dev/vmci. > */ > @@ -338,6 +343,8 @@ static int vmci_host_do_init_context(struct > vmci_host_dev *vmci_host_dev, > vmci_host_dev->ct_type = VMCIOBJ_CONTEXT; > atomic_inc(&vmci_host_active_users); > > + vmci_call_vsock_callback(true); > + Since we don't unregister the transport if user count drops back to 0, we could just call this the first time, a VM is powered on after the module is loaded. > retval = 0; > > out:

...> +{ > + return atomic_read(&vmci_host_active_users); > +} > + > /* > * Called on open of /dev/vmci. > */ > @@ -338,6 +343,8 @@ static int vmci_host_do_init_context(struct > vmci_host_dev *vmci_host_dev, > vmci_host_dev->ct_type = VMCIOBJ_CONTEXT; > atomic_inc(&vmci_host_active_users); > > + vmci_call_vsock_callback(true); > + Since we don't unregister the transport if user count drops back to 0, we could just call this the first time, a VM is powered on after the module is loaded. > retval = 0; > > out:

This patch should fix the bug reported in https://lkml.org/lkml/2014/9/11/249. Test is still pending. David Hildenbrand (1): blk-mq: Avoid race condition with uninitialized requests block/blk-mq.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) -- 1.8.5.5

This patch should fix the bug reported in https://lkml.org/lkml/2014/9/11/249. Test is still pending. David Hildenbrand (1): blk-mq: Avoid race condition with uninitialized requests block/blk-mq.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) -- 1.8.5.5

...rb_node *rb; struct btrfs_leaf_ref *ref = NULL; struct btrfs_leaf_ref_tree *tree = root->ref_tree; - - if (!tree) - return NULL; - - spin_lock(&tree->lock); - rb = tree_search(&tree->root, bytenr); - if (rb) - ref = rb_entry(rb, struct btrfs_leaf_ref, rb_node); - if (ref) - atomic_inc(&ref->usage); - spin_unlock(&tree->lock); - return ref; +again: + if (tree) { + spin_lock(&tree->lock); + rb = tree_search(&tree->root, bytenr); + if (rb) + ref = rb_entry(rb, struct btrfs_leaf_ref, rb_node); + if (ref) + atomic_inc(&ref->usage); + spin_u...

Convert the bridge forwarding database over to using RCU. This avoids a read_lock and atomic_inc/dec in the fast path of output. Signed-off-by: Stephen Hemminger <shemminger@osdl.org> diff -Nru a/include/linux/list.h b/include/linux/list.h --- a/include/linux/list.h 2004-07-28 15:30:04 -07:00 +++ b/include/linux/list.h 2004-07-28 15:30:04 -07:00 @@ -678,6 +678,24 @@ pos &&am...

...secondary mmu by calling * mmu_notifier_invalidate_range() see comments below inside @@ -2117,30 +2117,34 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, pte = pte_offset_map(&_pmd, addr); BUG_ON(!pte_none(*pte)); set_pte_at(mm, addr, pte, entry); - atomic_inc(&page[i]._mapcount); - pte_unmap(pte); - } - - /* - * Set PG_double_map before dropping compound_mapcount to avoid - * false-negative page_mapped(). - */ - if (compound_mapcount(page) > 1 && !TestSetPageDoubleMap(page)) { - for (i = 0; i < HPAGE_PMD_NR; i++) + if (!pmd_migra...

...st_vsock *vsock; - struct vhost_virtqueue *vq; int len = pkt->len; /* Find the vhost_vsock according to guest context id */ @@ -205,8 +204,6 @@ vhost_transport_send_pkt(struct virtio_vsock_pkt *pkt) return -ENODEV; } - vq = &vsock->vqs[VSOCK_VQ_RX]; - if (pkt->reply) atomic_inc(&vsock->queued_replies); -- 2.11.0.rc0.7.gbe5a750