clocksource/arm_arch_timer: Drop use of static key in arch_timer_reg_read_stable

Let's start with the removal of the arch_timer_read_ool_enabled
static key in arch_timer_reg_read_stable. It is not a fast path,
and we can simplify things a bit.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

diff --git a/arch/arm64/include/asm/arch_timer.h b/arch/arm64/include/asm/arch_timer.h
index c3762ffcc9330735ece07f79ca2f17b1cf50451e..4a06d46def7ed1e0f6146c330c7b22c9ba52c5e2 100644 (file)
--- a/arch/arm64/include/asm/arch_timer.h
+++ b/arch/arm64/include/asm/arch_timer.h
@@ -77,23 +77,37 @@ struct arch_timer_erratum_workaround {
 DECLARE_PER_CPU(const struct arch_timer_erratum_workaround *,
                timer_unstable_counter_workaround);
 
+/* inline sysreg accessors that make erratum_handler() work */
+static inline notrace u32 arch_timer_read_cntp_tval_el0(void)
+{
+       return read_sysreg(cntp_tval_el0);
+}
+
+static inline notrace u32 arch_timer_read_cntv_tval_el0(void)
+{
+       return read_sysreg(cntv_tval_el0);
+}
+
+static inline notrace u64 arch_timer_read_cntpct_el0(void)
+{
+       return read_sysreg(cntpct_el0);
+}
+
+static inline notrace u64 arch_timer_read_cntvct_el0(void)
+{
+       return read_sysreg(cntvct_el0);
+}
+
 #define arch_timer_reg_read_stable(reg)                                        \
-({                                                                     \
-       u64 _val;                                                       \
-       if (needs_unstable_timer_counter_workaround()) {                \
-               const struct arch_timer_erratum_workaround *wa;         \
+       ({                                                              \
+               u64 _val;                                               \
+                                                                       \
                preempt_disable_notrace();                              \
-               wa = __this_cpu_read(timer_unstable_counter_workaround); \
-               if (wa && wa->read_##reg)                               \
-                       _val = wa->read_##reg();                        \
-               else                                                    \
-                       _val = read_sysreg(reg);                        \
+               _val = erratum_handler(read_ ## reg)();                 \
                preempt_enable_notrace();                               \
-       } else {                                                        \
-               _val = read_sysreg(reg);                                \
-       }                                                               \
-       _val;                                                           \
-})
+                                                                       \
+               _val;                                                   \
+       })
 
 /*
  * These register accessors are marked inline so the compiler can