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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>
hifive-unleashed-5.2
Marc Zyngier 2019-04-08 16:49:05 +01:00 committed by Will Deacon
parent 5ef19a161c
commit 57f27666f9
1 changed files with 28 additions and 14 deletions
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42
arch/arm64/include/asm/arch_timer.h
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@ -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