[PATCH 1/3] clocksource/arm_arch_timer: mark arch_counter_get_* as notrace

From: Anders Roxell
Date: Mon Jun 03 2019 - 05:19:47 EST


When CONFIG_FUNCTION_GRAPH_TRACER is enabled we end up in this circular
call trace since function arch_counter_get_cntvct() isn't marked with no
trace:

[ 17.914934] Call trace:
[ 17.915211] ftrace_return_to_handler+0x194/0x288
[ 17.915551] return_to_handler+0x1c/0x38
[ 17.915855] trace_clock_local+0x38/0x88
[ 17.916159] function_graph_enter+0xf0/0x258
[ 17.916465] prepare_ftrace_return+0x60/0x90
[ 17.916772] ftrace_graph_caller+0x1c/0x24
[ 17.917093] arch_counter_get_cntvct+0x10/0x30
[ 17.917417] sched_clock+0x70/0x218
[ 17.917723] trace_clock_local+0x38/0x88
[ 17.918026] function_graph_enter+0xf0/0x258
[ 17.918332] prepare_ftrace_return+0x60/0x90
[ 17.918649] ftrace_graph_caller+0x1c/0x24
[ 17.918963] arch_counter_get_cntvct+0x10/0x30
[ 17.919286] sched_clock+0x70/0x218

Rework so that function arch_counter_get_cntvct() is marked with notrace.

Fixes: 0ea415390cd3 ("clocksource/arm_arch_timer: Use arch_timer_read_counter to access stable counters")
Signed-off-by: Anders Roxell <anders.roxell@xxxxxxxxxx>
---
drivers/clocksource/arm_arch_timer.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index b2a951a798e2..f4d5bd8fe906 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -149,22 +149,22 @@ u32 arch_timer_reg_read(int access, enum arch_timer_reg reg,
return val;
}

-static u64 arch_counter_get_cntpct_stable(void)
+static u64 notrace arch_counter_get_cntpct_stable(void)
{
return __arch_counter_get_cntpct_stable();
}

-static u64 arch_counter_get_cntpct(void)
+static u64 notrace arch_counter_get_cntpct(void)
{
return __arch_counter_get_cntpct();
}

-static u64 arch_counter_get_cntvct_stable(void)
+static u64 notrace arch_counter_get_cntvct_stable(void)
{
return __arch_counter_get_cntvct_stable();
}

-static u64 arch_counter_get_cntvct(void)
+static u64 notrace arch_counter_get_cntvct(void)
{
return __arch_counter_get_cntvct();
}
@@ -947,7 +947,7 @@ bool arch_timer_evtstrm_available(void)
return cpumask_test_cpu(raw_smp_processor_id(), &evtstrm_available);
}

-static u64 arch_counter_get_cntvct_mem(void)
+static u64 notrace arch_counter_get_cntvct_mem(void)
{
u32 vct_lo, vct_hi, tmp_hi;

--
2.20.1