diff options
| author | Laura Abbott <labbott@fedoraproject.org> | 2015-07-20 14:47:58 -0700 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2015-07-21 07:51:38 +0200 |
| commit | b51ef52df71cb28e9d90cd1d48b79bf19f0bab06 (patch) | |
| tree | b2f6d97f1f5b4e6a743d8e278d3f3a176b69735c /arch/x86/kernel/cpu/common.c | |
| parent | 9d634c410b07be7bf637ea03362d3ff132088fe3 (diff) | |
x86/cpu: Restore MSR_IA32_ENERGY_PERF_BIAS after resume
MSR_IA32_ENERGY_PERF_BIAS is lost after suspend/resume:
x86_energy_perf_policy -r before
cpu0: 0x0000000000000006
cpu1: 0x0000000000000006
cpu2: 0x0000000000000006
cpu3: 0x0000000000000006
cpu4: 0x0000000000000006
cpu5: 0x0000000000000006
cpu6: 0x0000000000000006
cpu7: 0x0000000000000006
after
cpu0: 0x0000000000000000
cpu1: 0x0000000000000006
cpu2: 0x0000000000000006
cpu3: 0x0000000000000006
cpu4: 0x0000000000000006
cpu5: 0x0000000000000006
cpu6: 0x0000000000000006
cpu7: 0x0000000000000006
Resulting in inconsistent energy policy settings across CPUs.
This register is set via init_intel() at bootup. During resume,
the secondary CPUs are brought online again and init_intel() is
callled which re-initializes the register. The boot CPU however
never reinitializes the register.
Add a syscore callback to reinitialize the register for the boot CPU.
Signed-off-by: Laura Abbott <labbott@fedoraproject.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1437428878-4105-1-git-send-email-labbott@fedoraproject.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/kernel/cpu/common.c')
| -rw-r--r-- | arch/x86/kernel/cpu/common.c | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 922c5e0cea4c..fa95bb8829ce 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -13,6 +13,7 @@ #include <linux/kgdb.h> #include <linux/smp.h> #include <linux/io.h> +#include <linux/syscore_ops.h> #include <asm/stackprotector.h> #include <asm/perf_event.h> @@ -1488,3 +1489,20 @@ inline bool __static_cpu_has_safe(u16 bit) return boot_cpu_has(bit); } EXPORT_SYMBOL_GPL(__static_cpu_has_safe); + +static void bsp_resume(void) +{ + if (this_cpu->c_bsp_resume) + this_cpu->c_bsp_resume(&boot_cpu_data); +} + +static struct syscore_ops cpu_syscore_ops = { + .resume = bsp_resume, +}; + +static int __init init_cpu_syscore(void) +{ + register_syscore_ops(&cpu_syscore_ops); + return 0; +} +core_initcall(init_cpu_syscore); |