linux/arch/x86/kernel/asm-offsets_32.c
Rusty Russell 61f4bc83fe lguest: optimize by coding restore_flags and irq_enable in assembler.
The downside of the last patch which made restore_flags and irq_enable
check interrupts is that they are now too big to be patched directly
into the callsites, so the C versions are always used.

But the C versions go via PV_CALLEE_SAVE_REGS_THUNK which saves all
the registers.  In fact, we don't need any registers in the fast path,
so we can do better than this if we actually code them in assembler.

The results are in the noise, but since it's about the same amount of
code, it's worth applying.

1GB Guest->Host: input(suppressed),output(suppressed)
Before:
	Seconds: 0:16.53
	Packets: 377268,753673
	Interrupts: 22461,24297
	Notifications: 1(5245),21303(732370)
	Net IRQs triggered: 377023(245),42578(711095)

After:
	Seconds: 0:16.48
	Packets: 377289,753673
	Interrupts: 22281,24465
	Notifications: 1(5245),21296(732377)
	Net IRQs triggered: 377060(229),42564(711109)

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-06-12 22:27:03 +09:30

152 lines
5.1 KiB
C

/*
* Generate definitions needed by assembly language modules.
* This code generates raw asm output which is post-processed
* to extract and format the required data.
*/
#include <linux/crypto.h>
#include <linux/sched.h>
#include <linux/signal.h>
#include <linux/personality.h>
#include <linux/suspend.h>
#include <linux/kbuild.h>
#include <asm/ucontext.h>
#include <asm/sigframe.h>
#include <asm/pgtable.h>
#include <asm/fixmap.h>
#include <asm/processor.h>
#include <asm/thread_info.h>
#include <asm/bootparam.h>
#include <asm/elf.h>
#include <asm/suspend.h>
#include <xen/interface/xen.h>
#include <linux/lguest.h>
#include "../../../drivers/lguest/lg.h"
/* workaround for a warning with -Wmissing-prototypes */
void foo(void);
void foo(void)
{
OFFSET(IA32_SIGCONTEXT_ax, sigcontext, ax);
OFFSET(IA32_SIGCONTEXT_bx, sigcontext, bx);
OFFSET(IA32_SIGCONTEXT_cx, sigcontext, cx);
OFFSET(IA32_SIGCONTEXT_dx, sigcontext, dx);
OFFSET(IA32_SIGCONTEXT_si, sigcontext, si);
OFFSET(IA32_SIGCONTEXT_di, sigcontext, di);
OFFSET(IA32_SIGCONTEXT_bp, sigcontext, bp);
OFFSET(IA32_SIGCONTEXT_sp, sigcontext, sp);
OFFSET(IA32_SIGCONTEXT_ip, sigcontext, ip);
BLANK();
OFFSET(CPUINFO_x86, cpuinfo_x86, x86);
OFFSET(CPUINFO_x86_vendor, cpuinfo_x86, x86_vendor);
OFFSET(CPUINFO_x86_model, cpuinfo_x86, x86_model);
OFFSET(CPUINFO_x86_mask, cpuinfo_x86, x86_mask);
OFFSET(CPUINFO_hard_math, cpuinfo_x86, hard_math);
OFFSET(CPUINFO_cpuid_level, cpuinfo_x86, cpuid_level);
OFFSET(CPUINFO_x86_capability, cpuinfo_x86, x86_capability);
OFFSET(CPUINFO_x86_vendor_id, cpuinfo_x86, x86_vendor_id);
BLANK();
OFFSET(TI_task, thread_info, task);
OFFSET(TI_exec_domain, thread_info, exec_domain);
OFFSET(TI_flags, thread_info, flags);
OFFSET(TI_status, thread_info, status);
OFFSET(TI_preempt_count, thread_info, preempt_count);
OFFSET(TI_addr_limit, thread_info, addr_limit);
OFFSET(TI_restart_block, thread_info, restart_block);
OFFSET(TI_sysenter_return, thread_info, sysenter_return);
OFFSET(TI_cpu, thread_info, cpu);
BLANK();
OFFSET(GDS_size, desc_ptr, size);
OFFSET(GDS_address, desc_ptr, address);
BLANK();
OFFSET(PT_EBX, pt_regs, bx);
OFFSET(PT_ECX, pt_regs, cx);
OFFSET(PT_EDX, pt_regs, dx);
OFFSET(PT_ESI, pt_regs, si);
OFFSET(PT_EDI, pt_regs, di);
OFFSET(PT_EBP, pt_regs, bp);
OFFSET(PT_EAX, pt_regs, ax);
OFFSET(PT_DS, pt_regs, ds);
OFFSET(PT_ES, pt_regs, es);
OFFSET(PT_FS, pt_regs, fs);
OFFSET(PT_GS, pt_regs, gs);
OFFSET(PT_ORIG_EAX, pt_regs, orig_ax);
OFFSET(PT_EIP, pt_regs, ip);
OFFSET(PT_CS, pt_regs, cs);
OFFSET(PT_EFLAGS, pt_regs, flags);
OFFSET(PT_OLDESP, pt_regs, sp);
OFFSET(PT_OLDSS, pt_regs, ss);
BLANK();
OFFSET(EXEC_DOMAIN_handler, exec_domain, handler);
OFFSET(IA32_RT_SIGFRAME_sigcontext, rt_sigframe, uc.uc_mcontext);
BLANK();
OFFSET(pbe_address, pbe, address);
OFFSET(pbe_orig_address, pbe, orig_address);
OFFSET(pbe_next, pbe, next);
/* Offset from the sysenter stack to tss.sp0 */
DEFINE(TSS_sysenter_sp0, offsetof(struct tss_struct, x86_tss.sp0) -
sizeof(struct tss_struct));
DEFINE(PAGE_SIZE_asm, PAGE_SIZE);
DEFINE(PAGE_SHIFT_asm, PAGE_SHIFT);
DEFINE(PTRS_PER_PTE, PTRS_PER_PTE);
DEFINE(PTRS_PER_PMD, PTRS_PER_PMD);
DEFINE(PTRS_PER_PGD, PTRS_PER_PGD);
OFFSET(crypto_tfm_ctx_offset, crypto_tfm, __crt_ctx);
#ifdef CONFIG_PARAVIRT
BLANK();
OFFSET(PARAVIRT_enabled, pv_info, paravirt_enabled);
OFFSET(PARAVIRT_PATCH_pv_cpu_ops, paravirt_patch_template, pv_cpu_ops);
OFFSET(PARAVIRT_PATCH_pv_irq_ops, paravirt_patch_template, pv_irq_ops);
OFFSET(PV_IRQ_irq_disable, pv_irq_ops, irq_disable);
OFFSET(PV_IRQ_irq_enable, pv_irq_ops, irq_enable);
OFFSET(PV_CPU_iret, pv_cpu_ops, iret);
OFFSET(PV_CPU_irq_enable_sysexit, pv_cpu_ops, irq_enable_sysexit);
OFFSET(PV_CPU_read_cr0, pv_cpu_ops, read_cr0);
#endif
#ifdef CONFIG_XEN
BLANK();
OFFSET(XEN_vcpu_info_mask, vcpu_info, evtchn_upcall_mask);
OFFSET(XEN_vcpu_info_pending, vcpu_info, evtchn_upcall_pending);
#endif
#if defined(CONFIG_LGUEST) || defined(CONFIG_LGUEST_GUEST) || defined(CONFIG_LGUEST_MODULE)
BLANK();
OFFSET(LGUEST_DATA_irq_enabled, lguest_data, irq_enabled);
OFFSET(LGUEST_DATA_irq_pending, lguest_data, irq_pending);
OFFSET(LGUEST_DATA_pgdir, lguest_data, pgdir);
BLANK();
OFFSET(LGUEST_PAGES_host_gdt_desc, lguest_pages, state.host_gdt_desc);
OFFSET(LGUEST_PAGES_host_idt_desc, lguest_pages, state.host_idt_desc);
OFFSET(LGUEST_PAGES_host_cr3, lguest_pages, state.host_cr3);
OFFSET(LGUEST_PAGES_host_sp, lguest_pages, state.host_sp);
OFFSET(LGUEST_PAGES_guest_gdt_desc, lguest_pages,state.guest_gdt_desc);
OFFSET(LGUEST_PAGES_guest_idt_desc, lguest_pages,state.guest_idt_desc);
OFFSET(LGUEST_PAGES_guest_gdt, lguest_pages, state.guest_gdt);
OFFSET(LGUEST_PAGES_regs_trapnum, lguest_pages, regs.trapnum);
OFFSET(LGUEST_PAGES_regs_errcode, lguest_pages, regs.errcode);
OFFSET(LGUEST_PAGES_regs, lguest_pages, regs);
#endif
BLANK();
OFFSET(BP_scratch, boot_params, scratch);
OFFSET(BP_loadflags, boot_params, hdr.loadflags);
OFFSET(BP_hardware_subarch, boot_params, hdr.hardware_subarch);
OFFSET(BP_version, boot_params, hdr.version);
OFFSET(BP_kernel_alignment, boot_params, hdr.kernel_alignment);
}