Re: [PATCH 3/4] RISC-V: Remove per cpu clocksource

From: Palmer Dabbelt
Date: Fri Dec 07 2018 - 12:00:17 EST


On Mon, 03 Dec 2018 12:57:30 PST (-0800), atish.patra@xxxxxxx wrote:
There is only one clocksource in RISC-V. The boot cpu initializes
that clocksource. No need to keep a percpu data structure.

Signed-off-by: Atish Patra <atish.patra@xxxxxxx>
---
drivers/clocksource/riscv_timer.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/clocksource/riscv_timer.c b/drivers/clocksource/riscv_timer.c
index 96af7058..39de6e49 100644
--- a/drivers/clocksource/riscv_timer.c
+++ b/drivers/clocksource/riscv_timer.c
@@ -49,7 +49,7 @@ static unsigned long long riscv_clocksource_rdtime(struct clocksource *cs)
return get_cycles64();
}

-static DEFINE_PER_CPU(struct clocksource, riscv_clocksource) = {
+static struct clocksource riscv_clocksource = {
.name = "riscv_clocksource",
.rating = 300,
.mask = CLOCKSOURCE_MASK(BITS_PER_LONG),
@@ -106,7 +106,6 @@ static long __init riscv_timebase_frequency(struct device_node *node)
static int __init riscv_timer_init_dt(struct device_node *n)
{
int cpuid, hartid, error;
- struct clocksource *cs;

hartid = riscv_of_processor_hartid(n);
cpuid = riscv_hartid_to_cpuid(hartid);
@@ -116,8 +115,7 @@ static int __init riscv_timer_init_dt(struct device_node *n)

/* This should be called only for boot cpu */
riscv_timebase = riscv_timebase_frequency(n);
- cs = per_cpu_ptr(&riscv_clocksource, cpuid);
- clocksource_register_hz(cs, riscv_timebase);
+ clocksource_register_hz(&riscv_clocksource, riscv_timebase);

error = cpuhp_setup_state(CPUHP_AP_RISCV_TIMER_STARTING,
"clockevents/riscv/timer:starting",

Reviewed-by: Palmer Dabbelt <palmer@xxxxxxxxxx>