ARM64: smp: Fix suspicious RCU usage with ipi tracepoints
authorStephen Boyd <sboyd@codeaurora.org>
Wed, 24 Jun 2015 20:14:18 +0000 (13:14 -0700)
committerCatalin Marinas <catalin.marinas@arm.com>
Thu, 25 Jun 2015 13:37:32 +0000 (14:37 +0100)
commitbe081d9bf3e163a9ed1ca2f0f14f08424c7f9016
treecff9e7c83739d35c1fd7e31919d06f80745ba939
parent86dca36e6ba019650a94cadf922ea3d06dec0182
ARM64: smp: Fix suspicious RCU usage with ipi tracepoints

John Stultz reported an RCU splat on ARM with ipi trace events
enabled. It looks like the same problem exists on ARM64.

At this point in the IPI handling path we haven't called
irq_enter() yet, so RCU doesn't know that we're about to exit
idle and properly warns that we're using RCU from an idle CPU.
Use trace_ipi_entry_rcuidle() instead of trace_ipi_entry() so
that RCU is informed about our exit from idle.

Cc: John Stultz <john.stultz@linaro.org>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org> # 3.17+
Fixes: 45ed695ac10a ("ARM64: add IPI tracepoints")
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
arch/arm64/kernel/smp.c