Re: [PATCH 3/3] tracing/mm: Don't trace mm_page_pcpu_drain on offline cpus

2015-05-08 Thread Shreyas B Prabhu
On Friday 08 May 2015 07:48 PM, Steven Rostedt wrote: > On Fri, 08 May 2015 10:07:15 +0530 > Shreyas B Prabhu wrote: > > >> Hi Steve, >> Do you have any other suggestions for this patchset or will you take >> them as is? > > I'm fine with them (add my Acked-by), but I don't usually pull in >

Re: [PATCH 3/3] tracing/mm: Don't trace mm_page_pcpu_drain on offline cpus

2015-05-08 Thread Steven Rostedt
On Fri, 08 May 2015 10:07:15 +0530 Shreyas B Prabhu wrote: > Hi Steve, > Do you have any other suggestions for this patchset or will you take > them as is? I'm fine with them (add my Acked-by), but I don't usually pull in changes for include/trace/events/*.h files. Those are usually maintained

Re: [PATCH 3/3] tracing/mm: Don't trace mm_page_pcpu_drain on offline cpus

2015-05-07 Thread Shreyas B Prabhu
On Wednesday 29 April 2015 10:38 PM, Steven Rostedt wrote: > On Wed, 29 Apr 2015 21:28:38 +0530 > Shreyas B Prabhu wrote: > >> >> >> On Wednesday 29 April 2015 08:48 PM, Steven Rostedt wrote: >>> On Wed, 29 Apr 2015 20:19:28 +0530 >>> Shreyas B Prabhu wrote: >>> IIUC there is no existing

Re: [PATCH 3/3] tracing/mm: Don't trace mm_page_pcpu_drain on offline cpus

2015-04-29 Thread Shreyas B Prabhu
On Thursday 30 April 2015 10:06 AM, Preeti Murthy wrote: > On Wed, Apr 29, 2015 at 10:49 PM, Shreyas B Prabhu > wrote: >> >> >> On Wednesday 29 April 2015 10:38 PM, Steven Rostedt wrote: I am not sure if its worth the effort now. It doesn't look like any other trace point apart from th

Re: [PATCH 3/3] tracing/mm: Don't trace mm_page_pcpu_drain on offline cpus

2015-04-29 Thread Preeti Murthy
On Wed, Apr 29, 2015 at 10:49 PM, Shreyas B Prabhu wrote: > > > On Wednesday 29 April 2015 10:38 PM, Steven Rostedt wrote: >>> I am not sure if its worth the effort now. It doesn't look like any >>> other trace point apart from the above use case will benefit from it. >>> Only smbus_write and smbu

Re: [PATCH 3/3] tracing/mm: Don't trace mm_page_pcpu_drain on offline cpus

2015-04-29 Thread Shreyas B Prabhu
On Wednesday 29 April 2015 10:38 PM, Steven Rostedt wrote: >> I am not sure if its worth the effort now. It doesn't look like any >> other trace point apart from the above use case will benefit from it. >> Only smbus_write and smbus_reply seem to come close. But even they need >> separate TP_fast

Re: [PATCH 3/3] tracing/mm: Don't trace mm_page_pcpu_drain on offline cpus

2015-04-29 Thread Steven Rostedt
On Wed, 29 Apr 2015 21:28:38 +0530 Shreyas B Prabhu wrote: > > > On Wednesday 29 April 2015 08:48 PM, Steven Rostedt wrote: > > On Wed, 29 Apr 2015 20:19:28 +0530 > > Shreyas B Prabhu wrote: > > > >> IIUC there is no existing macro which can both add a condition and > >> override printk forma

Re: [PATCH 3/3] tracing/mm: Don't trace mm_page_pcpu_drain on offline cpus

2015-04-29 Thread Shreyas B Prabhu
On Wednesday 29 April 2015 08:48 PM, Steven Rostedt wrote: > On Wed, 29 Apr 2015 20:19:28 +0530 > Shreyas B Prabhu wrote: > >> IIUC there is no existing macro which can both add a condition and >> override printk format, hence the fall back to TRACE_EVENT_CONDITION. > > Hmm, want me to send yo

Re: [PATCH 3/3] tracing/mm: Don't trace mm_page_pcpu_drain on offline cpus

2015-04-29 Thread Steven Rostedt
On Wed, 29 Apr 2015 20:19:28 +0530 Shreyas B Prabhu wrote: > IIUC there is no existing macro which can both add a condition and > override printk format, hence the fall back to TRACE_EVENT_CONDITION. Hmm, want me to send you a patch that changes that? -- Steve -- To unsubscribe from this list:

Re: [PATCH 3/3] tracing/mm: Don't trace mm_page_pcpu_drain on offline cpus

2015-04-29 Thread Shreyas B Prabhu
>> -DEFINE_EVENT_PRINT(mm_page, mm_page_pcpu_drain, >> +TRACE_EVENT_CONDITION(mm_page_pcpu_drain, >> >> TP_PROTO(struct page *page, unsigned int order, int migratetype), >> >> TP_ARGS(page, order, migratetype), >> >> + TP_CONDITION(cpu_online(smp_processor_id())), >> + >> +

Re: [PATCH 3/3] tracing/mm: Don't trace mm_page_pcpu_drain on offline cpus

2015-04-29 Thread Preeti Murthy
Ccing Paul, On Tue, Apr 28, 2015 at 9:21 PM, Shreyas B. Prabhu wrote: > Since tracepoints use RCU for protection, they must not be called on > offline cpus. trace_mm_page_pcpu_drain can be called on an offline cpu > in this scenario caught by LOCKDEP: > > === > [ INF

[PATCH 3/3] tracing/mm: Don't trace mm_page_pcpu_drain on offline cpus

2015-04-28 Thread Shreyas B. Prabhu
Since tracepoints use RCU for protection, they must not be called on offline cpus. trace_mm_page_pcpu_drain can be called on an offline cpu in this scenario caught by LOCKDEP: === [ INFO: suspicious RCU usage. ] 4.1.0-rc1+ #9 Not tainted