search for: preemptions

Hello, Has anyone already implemented some sort of call preemption in Asterisk ? I am trying to achieve something like this : - I want to limit the number of calls on a given SIP peer to 10 - on the other hand, some calls have higher priority than others - when the ceiling of 10 calls is reached and a call with a high priority is attempted, I would like to drop a call with a lower priority

...hreads will be preempted by which on my OpenSolaris machine. Therefore, I ran a multithreaded program "myprogram" with 32 threads on my 24-core Solaris machine. I make sure that each thread of my program has same priority (priority zero), so that we can reduce priority inversions (saving preemptions -- system overhead). However, I ran the following script whoprempt.d to see who preempted myprogram threads and got the following output Unlike what I thought, myprogram threads are preempted (for 2796 times -- last line of the output) by the threads of same myprogram. Could anyone explain why th...

Hey all, I'm investigating LLVM for use for a future project of mine, and I was wondering whether something is possible. Specifically, I'm wondering if there's a way to force preemption of a green thread-style task - something like Erlang's "processes", where if a task executes for too long, it is preempted. [1] My main goal here is to avoid having to write my own

Btw., another question that made me wonder already when doing the original patch: why is it that x86-64 properly uses locking for mm_pin_all(), yet i386 doesn''t need to? Jan _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel

On Thu, Mar 13, 2014 at 04:05:19PM -0400, Waiman Long wrote: > On 03/13/2014 11:15 AM, Peter Zijlstra wrote: > >On Wed, Mar 12, 2014 at 02:54:52PM -0400, Waiman Long wrote: > >>+static inline void arch_spin_lock(struct qspinlock *lock) > >>+{ > >>+ if (static_key_false(&paravirt_unfairlocks_enabled)) > >>+ queue_spin_lock_unfair(lock); >

On Thu, Mar 13, 2014 at 04:05:19PM -0400, Waiman Long wrote: > On 03/13/2014 11:15 AM, Peter Zijlstra wrote: > >On Wed, Mar 12, 2014 at 02:54:52PM -0400, Waiman Long wrote: > >>+static inline void arch_spin_lock(struct qspinlock *lock) > >>+{ > >>+ if (static_key_false(&paravirt_unfairlocks_enabled)) > >>+ queue_spin_lock_unfair(lock); >

Hi Xinhui, 2016-06-28 22:43 GMT+08:00 Pan Xinhui <xinhui.pan at linux.vnet.ibm.com>: > This is to fix some lock holder preemption issues. Some other locks > implementation do a spin loop before acquiring the lock itself. Currently > kernel has an interface of bool vcpu_is_preempted(int cpu). It take the cpu > as parameter and return true if the cpu is preempted. Then kernel can

Hi Xinhui, 2016-06-28 22:43 GMT+08:00 Pan Xinhui <xinhui.pan at linux.vnet.ibm.com>: > This is to fix some lock holder preemption issues. Some other locks > implementation do a spin loop before acquiring the lock itself. Currently > kernel has an interface of bool vcpu_is_preempted(int cpu). It take the cpu > as parameter and return true if the cpu is preempted. Then kernel can

change fomr v1: a simplier definition of default vcpu_is_preempted skip mahcine type check on ppc, and add config. remove dedicated macro. add one patch to drop overload of rwsem_spin_on_owner and mutex_spin_on_owner. add more comments thanks boqun and Peter's suggestion. This patch set aims to fix lock holder preemption issues. test-case: perf record -a perf bench sched messaging -g

change fomr v1: a simplier definition of default vcpu_is_preempted skip mahcine type check on ppc, and add config. remove dedicated macro. add one patch to drop overload of rwsem_spin_on_owner and mutex_spin_on_owner. add more comments thanks boqun and Peter's suggestion. This patch set aims to fix lock holder preemption issues. test-case: perf record -a perf bench sched messaging -g

Now that the kmap atomic index is stored in task struct provide a preemptible variant. On context switch the maps of an outgoing task are removed and the map of the incoming task are restored. That's obviously slow, but highmem is slow anyway. The kmap_local.*() functions can be invoked from both preemptible and atomic context. kmap local sections disable migration to keep the resulting

On Mon, Mar 17, 2014 at 01:44:34PM -0400, Waiman Long wrote: > On 03/14/2014 04:30 AM, Peter Zijlstra wrote: > >On Thu, Mar 13, 2014 at 04:05:19PM -0400, Waiman Long wrote: > >>On 03/13/2014 11:15 AM, Peter Zijlstra wrote: > >>>On Wed, Mar 12, 2014 at 02:54:52PM -0400, Waiman Long wrote: > >>>>+static inline void arch_spin_lock(struct qspinlock *lock)

On Mon, Mar 17, 2014 at 01:44:34PM -0400, Waiman Long wrote: > On 03/14/2014 04:30 AM, Peter Zijlstra wrote: > >On Thu, Mar 13, 2014 at 04:05:19PM -0400, Waiman Long wrote: > >>On 03/13/2014 11:15 AM, Peter Zijlstra wrote: > >>>On Wed, Mar 12, 2014 at 02:54:52PM -0400, Waiman Long wrote: > >>>>+static inline void arch_spin_lock(struct qspinlock *lock)

In debugging the sles9 port on 64 bit MP machines, I am seeing a problem where the hypervisor takes a fault in loading fs in the context switch code (load_segments()). The selector is one of the TLS selectors. It appears that the cpu in question has updated this selector with a value of 0 just prior to the problem I am seeing. Looking at the Linux context switch code, we first update the TLS

On Sat, Sep 30, 2017 at 12:05:52PM +0800, Wei Wang wrote: > +static inline void xb_set_page(struct virtio_balloon *vb, > + struct page *page, > + unsigned long *pfn_min, > + unsigned long *pfn_max) > +{ > + unsigned long pfn = page_to_pfn(page); > + > + *pfn_min = min(pfn, *pfn_min); > + *pfn_max = max(pfn, *pfn_max); > +

On Sat, Sep 30, 2017 at 12:05:52PM +0800, Wei Wang wrote: > +static inline void xb_set_page(struct virtio_balloon *vb, > + struct page *page, > + unsigned long *pfn_min, > + unsigned long *pfn_max) > +{ > + unsigned long pfn = page_to_pfn(page); > + > + *pfn_min = min(pfn, *pfn_min); > + *pfn_max = max(pfn, *pfn_max); > +

change from v2: no code change, fix typos, update some comments change from v1: a simplier definition of default vcpu_is_preempted skip mahcine type check on ppc, and add config. remove dedicated macro. add one patch to drop overload of rwsem_spin_on_owner and mutex_spin_on_owner. add more comments thanks boqun and Peter's suggestion. This patch set aims to fix lock holder preemption

change from v2: no code change, fix typos, update some comments change from v1: a simplier definition of default vcpu_is_preempted skip mahcine type check on ppc, and add config. remove dedicated macro. add one patch to drop overload of rwsem_spin_on_owner and mutex_spin_on_owner. add more comments thanks boqun and Peter's suggestion. This patch set aims to fix lock holder preemption

On 10/10/2017 09:09 PM, Tetsuo Handa wrote: > Wei Wang wrote: >>> And even if we could remove balloon_lock, you still cannot use >>> __GFP_DIRECT_RECLAIM at xb_set_page(). I think you will need to use >>> "whether it is safe to wait" flag from >>> "[PATCH] virtio: avoid possible OOM lockup at virtballoon_oom_notify()" . >> Without

On 10/11/2017 10:26 AM, Tetsuo Handa wrote: > Wei Wang wrote: >> On 10/10/2017 09:09 PM, Tetsuo Handa wrote: >>> Wei Wang wrote: >>>>> And even if we could remove balloon_lock, you still cannot use >>>>> __GFP_DIRECT_RECLAIM at xb_set_page(). I think you will need to use >>>>> "whether it is safe to wait" flag from