Re: [PATCH] latency improvement in __smp_call_single_queue

2020-09-24 Thread George Prekas
On 9/24/2020 3:42 AM, pet...@infradead.org wrote: > On Wed, Sep 23, 2020 at 10:00:41AM -0500, George Prekas wrote: >> If an interrupt arrives between llist_add and >> send_call_function_single_ipi in the following code snippet, then the >> remote CPU will not receive the IPI in a timely manner

Re: [PATCH] latency improvement in __smp_call_single_queue

2020-09-24 Thread peterz
On Wed, Sep 23, 2020 at 10:00:41AM -0500, George Prekas wrote: > If an interrupt arrives between llist_add and > send_call_function_single_ipi in the following code snippet, then the > remote CPU will not receive the IPI in a timely manner and subsequent > SMP calls even from other CPUs for other

[PATCH] latency improvement in __smp_call_single_queue

2020-09-23 Thread George Prekas
If an interrupt arrives between llist_add and send_call_function_single_ipi in the following code snippet, then the remote CPU will not receive the IPI in a timely manner and subsequent SMP calls even from other CPUs for other functions will be delayed:     if (llist_add(node,