Commit-ID: dc6ca5e47d44c11a111807208595ff6a8fcd2a83 Gitweb: http://git.kernel.org/tip/dc6ca5e47d44c11a111807208595ff6a8fcd2a83 Author: Suravee Suthikulpanit <[email protected]> AuthorDate: Fri, 24 Feb 2017 02:48:15 -0600 Committer: Ingo Molnar <[email protected]> CommitDate: Thu, 30 Mar 2017 09:53:52 +0200
x86/events/amd/iommu: Clean up perf_iommu_read() Fix coding style and use GENMASK_ULL(). Signed-off-by: Suravee Suthikulpanit <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Arnaldo Carvalho de Melo <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Jörg Rödel <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Stephane Eranian <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Vince Weaver <[email protected]> Cc: [email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]> --- arch/x86/events/amd/iommu.c | 16 ++++++---------- 1 file changed, 6 insertions(+), 10 deletions(-) diff --git a/arch/x86/events/amd/iommu.c b/arch/x86/events/amd/iommu.c index e112f49..d4375da 100644 --- a/arch/x86/events/amd/iommu.c +++ b/arch/x86/events/amd/iommu.c @@ -320,9 +320,7 @@ static void perf_iommu_start(struct perf_event *event, int flags) static void perf_iommu_read(struct perf_event *event) { - u64 count = 0ULL; - u64 prev_raw_count = 0ULL; - u64 delta = 0ULL; + u64 count, prev, delta; struct hw_perf_event *hwc = &event->hw; amd_iommu_pc_get_set_reg_val(_GET_DEVID(event), @@ -330,18 +328,16 @@ static void perf_iommu_read(struct perf_event *event) IOMMU_PC_COUNTER_REG, &count, false); /* IOMMU pc counter register is only 48 bits */ - count &= 0xFFFFFFFFFFFFULL; + count &= GENMASK_ULL(47, 0); - prev_raw_count = local64_read(&hwc->prev_count); - if (local64_cmpxchg(&hwc->prev_count, prev_raw_count, - count) != prev_raw_count) + prev = local64_read(&hwc->prev_count); + if (local64_cmpxchg(&hwc->prev_count, prev, count) != prev) return; - /* Handling 48-bit counter overflowing */ - delta = (count << COUNTER_SHIFT) - (prev_raw_count << COUNTER_SHIFT); + /* Handle 48-bit counter overflow */ + delta = (count << COUNTER_SHIFT) - (prev << COUNTER_SHIFT); delta >>= COUNTER_SHIFT; local64_add(delta, &event->count); - } static void perf_iommu_stop(struct perf_event *event, int flags)
