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charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org [extra 'Remove' in subject] On Wed, Jul 17, 2019 at 09:17:07AM +0100, Julien Thierry wrote: > Since the PMU interrupt saves and restores the value of the selector > register, there is no need to serialize register accesses against the > interrupt contexts. > > For operations that can be called with interrupts enabled, preemption > still needs to be disabled to ensure the programming of the PMU is > done on the expected CPU and not migrated mid-programming. > > Signed-off-by: Julien Thierry > Cc: Will Deacon > Cc: Mark Rutland > Cc: Peter Zijlstra > Cc: Ingo Molnar > Cc: Arnaldo Carvalho de Melo > Cc: Alexander Shishkin > Cc: Jiri Olsa > Cc: Namhyung Kim > Cc: Russell King > --- > arch/arm/kernel/perf_event_v7.c | 54 ++--------------------------------------- > 1 file changed, 2 insertions(+), 52 deletions(-) I'm struggling to see why this patch is needed or, if it is, why we're not doing something similar for v6 and xscale. Will _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel