From: Chen Yu <yu.c.c...@intel.com> The original problem comes from a bug found on MacBookPro that, the instructions run on each APs after resume are very slow, due to the MTRR been scribbled by the BIOS thus it behaves like running in 'uncached' mode.
Thus this patch tries to synchronize the MTRR as early as possible by performing this action once the APs have been brought. Test result shows a 6 seconds improvement on the bogus MacBookPro, and 600 ms improvement on a Xeon Broadwell platform which has 88 cpus. Chen Yu (3): PM / sleep: Introduce a flag to identify the enable_nonboot_cpus stage x86/mtrr: Add cpu id into the MTRR setting data structure PM / sleep: Do not delay the synchronization of MTRR during resume arch/x86/kernel/cpu/mtrr/main.c | 13 ++++++++++--- arch/x86/kernel/smpboot.c | 2 -- include/linux/cpu.h | 2 ++ kernel/cpu.c | 8 ++++++++ 4 files changed, 20 insertions(+), 5 deletions(-) -- 2.13.5
