arm64: topology: Fix false warning in counters_read_on_cpu() for same-CPU reads
The counters_read_on_cpu() function warns when called with IRQs
disabled to prevent deadlock in smp_call_function_single(). However,
this warning is spurious when reading counters on the current CPU,
since no IPI is needed for same CPU reads.
Commit 12eb8f4fff24 ("cpufreq: CPPC: Update FIE arch_freq_scale in
ticks for non-PCC regs") changed the CPPC Frequency Invariance Engine
to read AMU counters directly from the scheduler tick for non-PCC
register spaces (like FFH), instead of deferring to a kthread. This
means counters_read_on_cpu() is now called with IRQs disabled from the
tick handler, triggering the warning.
Fix this by restructuring the logic: when IRQs are disabled (tick
context), call the function directly for same-CPU reads. Otherwise
use smp_call_function_single().
Fixes: 997c021abc6e ("cpufreq: CPPC: Update FIE arch_freq_scale in ticks for non-PCC regs")
Suggested-by: Will Deacon <will@kernel.org>
Signed-off-by: Sumit Gupta <sumitg@nvidia.com>
Signed-off-by: Will Deacon <will@kernel.org>
1 file changed