Merge tag 'trace-fixes-v3.19-rc7' of...
Merge tag 'trace-fixes-v3.19-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull ftrace fixes from Steven Rostedt: "During testing Sedat Dilek hit a "suspicious RCU usage" splat that pointed out a real bug. During suspend and resume the tlb_flush tracepoint is called when the CPU is going offline. As the CPU has been noted as offline, RCU is ignoring that CPU, which means that it can not use RCU protected locks. When tracepoints are activated, they require RCU locking, and if RCU is ignoring a CPU that runs a tracepoint, there is a chance that the tracepoint could cause corruption. The solution was to change the tracepoint into a TRACE_EVENT_CONDITION() which allows us to check a condition to determine if the tracepoint should be called or not. If the condition is not met, the rcu protected code will not be executed. By adding the condition "cpu_online(smp_processor_id())", this will prevent the RCU protected code from being executed if the CPU i...
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