On Wed, Feb 15, 2023 at 02:54:17PM +0000, Usama Arif wrote: > The main change over v8 is dropping the patch to avoid repeated saves of MTRR > at boot time. It didn't make a difference to smpboot time and is independent > of parallel CPU bringup, so if needed can be explored in a separate patchset. > > The patches have also been rebased to v6.2-rc8 and retested and the > improvement in boot time is the same as v8. This version passes moderate torture testing. Tested-by: Paul E. McKenney <paulmck@xxxxxxxxxx> > Thanks, > Usama > > Changes across versions: > v2: Cut it back to just INIT/SIPI/SIPI in parallel for now, nothing more > v3: Clean up x2apic patch, add MTRR optimisation, lock topology update > in preparation for more parallelisation. > v4: Fixes to the real mode parallelisation patch spotted by SeanC, to > avoid scribbling on initial_gs in common_cpu_up(), and to allow all > 24 bits of the physical X2APIC ID to be used. That patch still needs > a Signed-off-by from its original author, who once claimed not to > remember writing it at all. But now we've fixed it, hopefully he'll > admit it now :) > v5: rebase to v6.1 and remeasure performance, disable parallel bringup > for AMD CPUs. > v6: rebase to v6.2-rc6, disabled parallel boot on amd as a cpu bug and > reused timer calibration for secondary CPUs. > v7: [David Woodhouse] iterate over all possible CPUs to find any existing > cluster mask in alloc_clustermask. (patch 1/9) > Keep parallel AMD support enabled in AMD, using APIC ID in CPUID leaf > 0x0B (for x2APIC mode) or CPUID leaf 0x01 where 8 bits are sufficient. > Included sanity checks for APIC id from 0x0B. (patch 6/9) > Removed patch for reusing timer calibration for secondary CPUs. > commit message and code improvements. > v8: Fix CPU0 hotplug by setting up the initial_gs, initial_stack and > early_gdt_descr. > Drop trampoline lock and bail if APIC ID not found in find_cpunr. > Code comments improved and debug prints added. > v9: Drop patch to avoid repeated saves of MTRR at boot time. > rebased and retested at v6.2-rc8. > added kernel doc for no_parallel_bringup and made do_parallel_bringup > __ro_after_init. > > David Woodhouse (8): > x86/apic/x2apic: Allow CPU cluster_mask to be populated in parallel > cpu/hotplug: Move idle_thread_get() to <linux/smpboot.h> > cpu/hotplug: Add dynamic parallel bringup states before > CPUHP_BRINGUP_CPU > x86/smpboot: Reference count on smpboot_setup_warm_reset_vector() > x86/smpboot: Split up native_cpu_up into separate phases and document > them > x86/smpboot: Support parallel startup of secondary CPUs > x86/smpboot: Send INIT/SIPI/SIPI to secondary CPUs in parallel > x86/smpboot: Serialize topology updates for secondary bringup > > .../admin-guide/kernel-parameters.txt | 3 + > arch/x86/include/asm/realmode.h | 3 + > arch/x86/include/asm/smp.h | 14 +- > arch/x86/include/asm/topology.h | 2 - > arch/x86/kernel/acpi/sleep.c | 1 + > arch/x86/kernel/apic/apic.c | 2 +- > arch/x86/kernel/apic/x2apic_cluster.c | 130 ++++--- > arch/x86/kernel/cpu/common.c | 6 +- > arch/x86/kernel/head_64.S | 99 ++++- > arch/x86/kernel/smpboot.c | 350 +++++++++++++----- > arch/x86/realmode/init.c | 3 + > arch/x86/realmode/rm/trampoline_64.S | 14 + > arch/x86/xen/smp_pv.c | 4 +- > include/linux/cpuhotplug.h | 2 + > include/linux/smpboot.h | 7 + > kernel/cpu.c | 31 +- > kernel/smpboot.c | 2 +- > kernel/smpboot.h | 2 - > 18 files changed, 515 insertions(+), 160 deletions(-) > > -- > 2.25.1 >
