1
linux/arch/x86/kernel
Andi Kleen ca74a6f84e x86: optimize lock prefix switching to run less frequently
On VMs implemented using JITs that cache translated code changing the lock
prefixes is a quite costly operation that forces the JIT to throw away and
retranslate a lot of code.

Previously a SMP kernel would rewrite the locks once for each CPU which
is quite unnecessary. This patch changes the code to never switch at boot in
 the normal case (SMP kernel booting with >1 CPU) or only once for SMP kernel
on UP.

This makes a significant difference in boot up performance on AMD SimNow!
Also I expect it to be a little faster on native systems too because a smp
switch does a lot of text_poke()s which each synchronize the pipeline.

v1->v2: Rename max_cpus
v1->v2: Fix off by one in UP check (Thomas Gleixner)

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:33:17 +01:00
..
acpi x86: unify arch/x86/kernel/acpi/sleep*.c 2008-01-30 13:32:54 +01:00
cpu x86: use the correct cpuid method to detect MWAIT support for C states 2008-01-30 13:33:16 +01:00
.gitignore .gitignore update for x86 arch 2007-10-17 21:19:04 +02:00
alternative.c x86: optimize lock prefix switching to run less frequently 2008-01-30 13:33:17 +01:00
aperture_64.c x86: disable the GART early, 64-bit 2008-01-30 13:33:09 +01:00
apic_32.c x86: preset apic clockevents multiplicator 2008-01-30 13:33:04 +01:00
apic_64.c x86: reduce memory and intra-node effects 2008-01-30 13:33:14 +01:00
apm_32.c x86: isolate PIC/PIT in/out calls 2008-01-30 13:33:14 +01:00
asm-offsets_32.c x86: unify struct desc_ptr 2008-01-30 13:31:12 +01:00
asm-offsets_64.c x86: unify tss_struct 2008-01-30 13:31:31 +01:00
asm-offsets.c i386: move kernel 2007-10-11 11:17:01 +02:00
audit_64.c x86_64: move kernel 2007-10-11 11:17:24 +02:00
bootflag.c x86: coding style cleanup for kernel/bootflag.c 2008-01-30 13:32:31 +01:00
bugs_64.c Delete filenames in comments. 2007-10-13 10:01:23 -07:00
cpuid.c PM: Acquire device locks on suspend 2008-01-24 20:40:04 -08:00
crash_dump_32.c kmap leak fix for x86_32 kdump 2007-10-19 11:53:33 -07:00
crash_dump_64.c Delete filenames in comments. 2007-10-13 10:01:23 -07:00
crash.c x86: disable hpet legacy replacement for kdump 2007-12-03 17:17:10 +01:00
doublefault_32.c x86: unify tss_struct 2008-01-30 13:31:31 +01:00
ds.c x86, ptrace: support 32bit-cross-64bit BTS recording 2008-01-30 13:32:03 +01:00
e820_32.c x86 boot: use E820 memory map on EFI 32 platform 2008-01-30 13:31:19 +01:00
e820_64.c x86: replace hard coded reservations in 64-bit early boot code with dynamic table 2008-01-30 13:33:17 +01:00
early_printk.c [x86] remove uses of magic macros for boot_params access 2007-10-16 17:38:31 -07:00
early-quirks.c x86: clean up arch/x86/kernel/early-quirks.c 2008-01-30 13:31:26 +01:00
efi_32.c x86: 32-bit EFI runtime service support: fixes in sync with 64-bit support 2008-01-30 13:32:11 +01:00
efi_64.c x86/efi: fix improper use of lvalue 2008-01-30 13:32:44 +01:00
efi_stub_32.S i386: move kernel 2007-10-11 11:17:01 +02:00
efi_stub_64.S x86: EFI runtime service support 2008-01-30 13:31:19 +01:00
efi.c x86: 32-bit EFI runtime service support: fixes in sync with 64-bit support 2008-01-30 13:32:11 +01:00
entry_32.S x86: move to .rodata/.init.data 2008-01-30 13:31:23 +01:00
entry_64.S x86: replace privileged instructions with paravirt macros 2008-01-30 13:32:08 +01:00
genapic_64.c x86: cleanup x86_cpu_to_apicid references 2008-01-30 13:33:11 +01:00
genapic_flat_64.c x86: convert cpu_to_apicid to be a per cpu variable 2007-10-19 20:35:03 +02:00
geode_32.c x86: Geode Multi-Function General Purpose Timers support 2007-10-12 23:04:06 +02:00
head64.c x86: replace hard coded reservations in 64-bit early boot code with dynamic table 2008-01-30 13:33:17 +01:00
head_32.S x86: early fault debugging improvement 2008-01-30 13:33:09 +01:00
head_64.S x86: make early printk selectable on 64-bit as well 2008-01-30 13:33:06 +01:00
hpet.c x86: remove duplicate includes 2008-01-30 13:30:32 +01:00
i386_ksyms_32.c x86: unexport __{read,write}_lock_failed 2008-01-30 13:30:29 +01:00
i387.c x86: x86 user_regset cleanup 2008-01-30 13:31:55 +01:00
i8237.c Driver core: change sysdev classes to use dynamic kobject names 2008-01-24 20:40:40 -08:00
i8253.c x86: isolate PIC/PIT in/out calls 2008-01-30 13:33:14 +01:00
i8259_32.c x86: isolate PIC/PIT in/out calls 2008-01-30 13:33:14 +01:00
i8259_64.c x86: isolate PIC/PIT in/out calls 2008-01-30 13:33:14 +01:00
init_task.c x86: nuke a ton of unused exports 2008-01-30 13:30:28 +01:00
io_apic_32.c arch/x86/kernel/io_apic_{64,32}.c: use time_before 2008-01-30 13:32:19 +01:00
io_apic_64.c arch/x86/kernel/io_apic_{64,32}.c: use time_before 2008-01-30 13:32:19 +01:00
io_delay.c x86: add DMI quirk for io-delay hangs on Compaq Presario V6000 laptops 2008-01-30 13:30:05 +01:00
ioport.c x86: refactor ioport unification 2008-01-30 13:33:10 +01:00
irq_32.c x86: remove all definitions with fastcall 2008-01-30 13:31:17 +01:00
irq_64.c x86: rename the struct pt_regs members for 32/64-bit consistency 2008-01-30 13:30:56 +01:00
k8.c x86_64: move kernel 2007-10-11 11:17:24 +02:00
kdebugfs.c x86 boot : export boot_params via debugfs for debugging 2008-01-30 13:32:51 +01:00
kprobes.c x86: fix singlestep handling in reenter_kprobe 2008-01-30 13:33:13 +01:00
ldt.c x86: adjust/fix LDT handling for Xen 2008-01-30 13:33:14 +01:00
machine_kexec_32.c x86: unify struct desc_ptr 2008-01-30 13:31:12 +01:00
machine_kexec_64.c x86: 64-bit, make sparsemem vmemmap the only memory model 2008-01-30 13:30:47 +01:00
Makefile x86: ioport_{32|64}.c unification 2008-01-30 13:33:10 +01:00
mca_32.c Delete filenames in comments. 2007-10-13 10:01:23 -07:00
mfgpt_32.c x86: GEODE fix a race condition in the MFGPT timer tick 2008-01-22 23:30:16 +01:00
microcode.c cpu-hotplug: replace lock_cpu_hotplug() with get_online_cpus() 2008-01-25 21:08:02 +01:00
module_32.c i386: move kernel 2007-10-11 11:17:01 +02:00
module_64.c x86_64: move kernel 2007-10-11 11:17:24 +02:00
mpparse_32.c x86: smp_scan_config() debugging printouts 2008-01-30 13:33:08 +01:00
mpparse_64.c x86: reduce memory and intra-node effects 2008-01-30 13:33:14 +01:00
msr.c PM: Acquire device locks on suspend 2008-01-24 20:40:04 -08:00
nmi_32.c x86: clean up nmi_32/64.c 2008-01-30 13:30:33 +01:00
nmi_64.c x86: clean up nmi_32/64.c 2008-01-30 13:30:33 +01:00
numaq_32.c i386: move kernel 2007-10-11 11:17:01 +02:00
paravirt_patch_32.c x86: move patching code to arch-specific file. 2008-01-30 13:32:10 +01:00
paravirt_patch_64.c x86: patching functions on 64-bit 2008-01-30 13:32:10 +01:00
paravirt.c replace x86_read/write_per_cpu with a common function. 2008-01-30 13:32:11 +01:00
pci-calgary_64.c x86: remove duplicate includes 2008-01-30 13:30:32 +01:00
pci-dma_32.c i386: Clean up duplicate includes in arch/i386/kernel/ 2007-10-17 20:15:51 +02:00
pci-dma_64.c x86: pci-dma_64.c: cleanups 2008-01-30 13:30:31 +01:00
pci-gart_64.c x86: add the capability to print fuzzy backtraces 2008-01-30 13:33:07 +01:00
pci-nommu_64.c x86 gart: rename iommu.h to gart.h 2007-10-30 00:22:22 +01:00
pci-swiotlb_64.c x86: nuke a ton of unused exports 2008-01-30 13:30:28 +01:00
pcspeaker.c i386: move kernel 2007-10-11 11:17:01 +02:00
pmtimer_64.c x86: move pmtmr related declarations 2008-01-30 13:30:18 +01:00
process_32.c x86: use the correct cpuid method to detect MWAIT support for C states 2008-01-30 13:33:16 +01:00
process_64.c x86: use the correct cpuid method to detect MWAIT support for C states 2008-01-30 13:33:16 +01:00
ptrace.c x86, ptrace: add bts_struct size to status command 2008-01-30 13:32:54 +01:00
quirks.c x86: Add HPET force support for MCP55 (nForce 5) chipsets 2007-10-23 22:37:25 +02:00
reboot_fixups_32.c x86: reboot fixup for wrap2c board 2007-11-17 16:27:02 +01:00
reboot.c x86: reboot_{32|64}.c unification 2008-01-30 13:32:51 +01:00
relocate_kernel_32.S i386: move kernel 2007-10-11 11:17:01 +02:00
relocate_kernel_64.S x86_64: move kernel 2007-10-11 11:17:24 +02:00
rtc.c x86: fix sched_clock() 2008-01-30 13:32:40 +01:00
scx200_32.c long vs. unsigned long - low-hanging fruits in drivers 2007-10-14 12:41:51 -07:00
setup64.c x86 boot : export boot_params via debugfs for debugging 2008-01-30 13:32:51 +01:00
setup_32.c i386: handle an initrd in highmem (version 2) 2008-01-30 13:32:51 +01:00
setup_64.c x86: replace hard coded reservations in 64-bit early boot code with dynamic table 2008-01-30 13:33:17 +01:00
sigframe_32.h i386: move kernel 2007-10-11 11:17:01 +02:00
signal_32.c x86: remove all definitions with fastcall 2008-01-30 13:31:17 +01:00
signal_64.c x86: get rid of _MASK flags 2008-01-30 13:31:27 +01:00
smp_32.c x86: voluntary leave_mm before entering ACPI C3 2008-01-30 13:32:01 +01:00
smp_64.c x86: voluntary leave_mm before entering ACPI C3 2008-01-30 13:32:01 +01:00
smpboot_32.c x86: cleanup x86_cpu_to_apicid references 2008-01-30 13:33:11 +01:00
smpboot_64.c x86: change bios_cpu_apicid to percpu data variable 2008-01-30 13:33:12 +01:00
smpcommon_32.c x86: change write_gdt_entry signature. 2008-01-30 13:31:13 +01:00
srat_32.c i386: move kernel 2007-10-11 11:17:01 +02:00
stacktrace.c x86: pull bp calculation earlier into the backtrace path 2008-01-30 13:33:07 +01:00
step.c x86: remove last user of get_segment_eip 2008-01-30 13:33:12 +01:00
summit_32.c spelling fixes: arch/i386/ 2007-10-20 01:13:56 +02:00
suspend_64.c x86: make __{save,restore}_processor_state static 2008-01-30 13:31:23 +01:00
suspend_asm_64.S x86: rename the struct pt_regs members for 32/64-bit consistency 2008-01-30 13:30:56 +01:00
sys_i386_32.c remove include/asm-*/ipc.h 2007-10-17 08:42:55 -07:00
sys_x86_64.c x86: PIE executable randomization, checkpatch fixes 2008-01-30 13:31:07 +01:00
syscall_64.c i386/x86_64: move headers to include/asm-x86 2007-10-11 11:20:03 +02:00
syscall_table_32.S i386: move kernel 2007-10-11 11:17:01 +02:00
tce_64.c x86: Create clflush() inline, remove hardcoded wbinvd 2007-10-17 20:16:12 +02:00
time_32.c x86: rename the struct pt_regs members for 32/64-bit consistency 2008-01-30 13:30:56 +01:00
time_64.c x86: remove get_cycles_sync 2008-01-30 13:32:39 +01:00
tls.c x86: x86 user_regset TLS 2008-01-30 13:31:52 +01:00
tls.h x86: x86 user_regset TLS 2008-01-30 13:31:52 +01:00
topology.c x86: change NR_CPUS arrays in topology 2008-01-30 13:33:11 +01:00
trampoline_32.S x86: misc. constifications 2007-10-17 20:16:08 +02:00
trampoline_64.S x86: misc. constifications 2007-10-17 20:16:08 +02:00
traps_32.c x86: pull bp calculation earlier into the backtrace path 2008-01-30 13:33:07 +01:00
traps_64.c x86: make printk_address regs->ip always reliable 2008-01-30 13:33:08 +01:00
tsc_32.c x86: allow TSC clock source on AMD Fam10h and some cleanup 2008-01-30 13:32:40 +01:00
tsc_64.c x86: remove explicit C3 TSC check on 64bit 2008-01-30 13:32:41 +01:00
tsc_sync.c x86: remove get_cycles_sync 2008-01-30 13:32:39 +01:00
verify_cpu_64.S x86_64: move kernel 2007-10-11 11:17:24 +02:00
vm86_32.c arch/x86/: spelling fixes 2008-01-30 13:31:42 +01:00
vmi_32.c x86/vmi: fix compilation as a result of pte_t changes 2008-01-30 13:32:58 +01:00
vmiclock_32.c x86: isolate PIC/PIT in/out calls 2008-01-30 13:33:14 +01:00
vmlinux_32.lds.S x86: make arch/x86/kernel/acpi/wakeup_32.S use a separate 2008-01-30 13:32:50 +01:00
vmlinux_64.lds.S x86-64: clean up linker script 2008-01-30 13:33:14 +01:00
vmlinux.lds.S i386: move kernel 2007-10-11 11:17:01 +02:00
vsmp_64.c x86: clean up arch/x86/kernel/vsmp_64.c 2008-01-30 13:30:24 +01:00
vsyscall_64.c x86: map vsyscalls early enough 2008-01-30 13:32:39 +01:00
x8664_ksyms_64.c x86: export cpu_gdt_descr 2008-01-30 13:31:10 +01:00