| Message ID | 20190611152135.44589-1-liwei391@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | clocksource/arm_arch_timer: mark arch_timer_read_counter() as notrace to avoid deadloop | expand |
Hi Wei, On 11/06/2019 16:21, Wei Li wrote: > According to arch_counter_register(), mark arch_counter_get_*() what > arch_timer_read_counter() can be as notrace to avoid deadloop when using > function_graph tracer. > > 0xffff80028af23250 0xffff000010195e00 sched_clock+64 > 0xffff80028af23290 0xffff0000101e83ec trace_clock_local+12 > 0xffff80028af232a0 0xffff00001020e52c function_graph_enter+116 > 0xffff80028af23300 0xffff00001009af9c prepare_ftrace_return+44 > 0xffff80028af23320 0xffff00001009b0a8 ftrace_graph_caller+28 > 0xffff80028af23330 0xffff000010b01918 arch_counter_get_cntvct+16 > 0xffff80028af23340 0xffff000010195e00 sched_clock+64 > 0xffff80028af23380 0xffff0000101e83ec trace_clock_local+12 > 0xffff80028af23390 0xffff00001020e52c function_graph_enter+116 > 0xffff80028af233f0 0xffff00001009af9c prepare_ftrace_return+44 > 0xffff80028af23410 0xffff00001009b0a8 ftrace_graph_caller+28 > 0xffff80028af23420 0xffff000010b01918 arch_counter_get_cntvct+16 > ... > > Fixes: 0ea415390cd3 ("clocksource/arm_arch_timer: Use arch_timer_read_counter to access stable counters") > Signed-off-by: Wei Li <liwei391@huawei.com> There is already a patch[1] queued for that. Hopefully Daniel and Thomas will get this into mainline shortly. Thanks, M. [1] https://lore.kernel.org/lkml/20190524093600.11ca3cb2@gandalf.local.home/T/
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;
According to arch_counter_register(), mark arch_counter_get_*() what arch_timer_read_counter() can be as notrace to avoid deadloop when using function_graph tracer. 0xffff80028af23250 0xffff000010195e00 sched_clock+64 0xffff80028af23290 0xffff0000101e83ec trace_clock_local+12 0xffff80028af232a0 0xffff00001020e52c function_graph_enter+116 0xffff80028af23300 0xffff00001009af9c prepare_ftrace_return+44 0xffff80028af23320 0xffff00001009b0a8 ftrace_graph_caller+28 0xffff80028af23330 0xffff000010b01918 arch_counter_get_cntvct+16 0xffff80028af23340 0xffff000010195e00 sched_clock+64 0xffff80028af23380 0xffff0000101e83ec trace_clock_local+12 0xffff80028af23390 0xffff00001020e52c function_graph_enter+116 0xffff80028af233f0 0xffff00001009af9c prepare_ftrace_return+44 0xffff80028af23410 0xffff00001009b0a8 ftrace_graph_caller+28 0xffff80028af23420 0xffff000010b01918 arch_counter_get_cntvct+16 ... Fixes: 0ea415390cd3 ("clocksource/arm_arch_timer: Use arch_timer_read_counter to access stable counters") Signed-off-by: Wei Li <liwei391@huawei.com> --- drivers/clocksource/arm_arch_timer.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-)