From: Vincent Minet <[email protected]> 3.12-stable review patch. If anyone has any objections, please let me know.
=============== commit 179e8471673ce0249cd4ecda796008f7757e5bad upstream. Ensure that cpu->cpu is set before writing MSR_IA32_PERF_CTL during CPU initialization. Otherwise only cpu0 has its P-state set and all other cores are left with their values unchanged. In most cases, this is not too serious because the P-states will be set correctly when the timer function is run. But when the default governor is set to performance, the per-CPU current_pstate stays the same forever and no attempts are made to write the MSRs again. Signed-off-by: Vincent Minet <[email protected]> Signed-off-by: Rafael J. Wysocki <[email protected]> Signed-off-by: Jiri Slaby <[email protected]> --- drivers/cpufreq/intel_pstate.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index d5dc567efd96..f033fadb58e6 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -550,6 +550,7 @@ static int intel_pstate_init_cpu(unsigned int cpunum) cpu = all_cpu_data[cpunum]; + cpu->cpu = cpunum; intel_pstate_get_cpu_pstates(cpu); if (!cpu->pstate.current_pstate) { all_cpu_data[cpunum] = NULL; @@ -557,7 +558,6 @@ static int intel_pstate_init_cpu(unsigned int cpunum) return -ENODATA; } - cpu->cpu = cpunum; cpu->pstate_policy = (struct pstate_adjust_policy *)id->driver_data; init_timer_deferrable(&cpu->timer); -- 2.0.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
