Messages in this thread | | | Date | Fri, 04 Jun 2010 10:23:57 +0800 | From | Lai Jiangshan <> | Subject | Re: [PATCH] tracing: reduce latency and remove percpu trace_seq |
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Steven Rostedt wrote:
> > The "print" in the trace_seq_printf() is the TP_printk() field of the > TRACE_EVENT. I believe that there were some events (ext4?) that did > things that required preemption disabled. >
It seems that ext4 has no such events. I find jbd2_dev_to_name() in the TP_printk() field of ext4's tracepoints. And it seems that jbd2_dev_to_name() requires preemption enabled and sleepable.
Maybe there were some events did things that required preemption disabled. But No document ensure TP_printk() preemption disabled, such events should be fixed, I think.
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