diff options
Diffstat (limited to 'arch/x86/xen/enlighten_pv.c')
-rw-r--r-- | arch/x86/xen/enlighten_pv.c | 40 |
1 files changed, 33 insertions, 7 deletions
diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c index 49352fad7d1d..bbbfdd495ebd 100644 --- a/arch/x86/xen/enlighten_pv.c +++ b/arch/x86/xen/enlighten_pv.c @@ -101,6 +101,17 @@ struct tls_descs { struct desc_struct desc[3]; }; +DEFINE_PER_CPU(enum xen_lazy_mode, xen_lazy_mode) = XEN_LAZY_NONE; +DEFINE_PER_CPU(unsigned int, xen_lazy_nesting); + +enum xen_lazy_mode xen_get_lazy_mode(void) +{ + if (in_interrupt()) + return XEN_LAZY_NONE; + + return this_cpu_read(xen_lazy_mode); +} + /* * Updating the 3 TLS descriptors in the GDT on every task switch is * surprisingly expensive so we avoid updating them if they haven't @@ -362,10 +373,25 @@ static noinstr unsigned long xen_get_debugreg(int reg) return HYPERVISOR_get_debugreg(reg); } +static void xen_start_context_switch(struct task_struct *prev) +{ + BUG_ON(preemptible()); + + if (this_cpu_read(xen_lazy_mode) == XEN_LAZY_MMU) { + arch_leave_lazy_mmu_mode(); + set_ti_thread_flag(task_thread_info(prev), TIF_LAZY_MMU_UPDATES); + } + enter_lazy(XEN_LAZY_CPU); +} + static void xen_end_context_switch(struct task_struct *next) { + BUG_ON(preemptible()); + xen_mc_flush(); - paravirt_end_context_switch(next); + leave_lazy(XEN_LAZY_CPU); + if (test_and_clear_ti_thread_flag(task_thread_info(next), TIF_LAZY_MMU_UPDATES)) + arch_enter_lazy_mmu_mode(); } static unsigned long xen_store_tr(void) @@ -472,7 +498,7 @@ static void xen_set_ldt(const void *addr, unsigned entries) MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF); - xen_mc_issue(PARAVIRT_LAZY_CPU); + xen_mc_issue(XEN_LAZY_CPU); } static void xen_load_gdt(const struct desc_ptr *dtr) @@ -568,7 +594,7 @@ static void xen_load_tls(struct thread_struct *t, unsigned int cpu) * exception between the new %fs descriptor being loaded and * %fs being effectively cleared at __switch_to(). */ - if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_CPU) + if (xen_get_lazy_mode() == XEN_LAZY_CPU) loadsegment(fs, 0); xen_mc_batch(); @@ -577,7 +603,7 @@ static void xen_load_tls(struct thread_struct *t, unsigned int cpu) load_TLS_descriptor(t, cpu, 1); load_TLS_descriptor(t, cpu, 2); - xen_mc_issue(PARAVIRT_LAZY_CPU); + xen_mc_issue(XEN_LAZY_CPU); } static void xen_load_gs_index(unsigned int idx) @@ -909,7 +935,7 @@ static void xen_load_sp0(unsigned long sp0) mcs = xen_mc_entry(0); MULTI_stack_switch(mcs.mc, __KERNEL_DS, sp0); - xen_mc_issue(PARAVIRT_LAZY_CPU); + xen_mc_issue(XEN_LAZY_CPU); this_cpu_write(cpu_tss_rw.x86_tss.sp0, sp0); } @@ -973,7 +999,7 @@ static void xen_write_cr0(unsigned long cr0) MULTI_fpu_taskswitch(mcs.mc, (cr0 & X86_CR0_TS) != 0); - xen_mc_issue(PARAVIRT_LAZY_CPU); + xen_mc_issue(XEN_LAZY_CPU); } static void xen_write_cr4(unsigned long cr4) @@ -1156,7 +1182,7 @@ static const typeof(pv_ops) xen_cpu_ops __initconst = { #endif .io_delay = xen_io_delay, - .start_context_switch = paravirt_start_context_switch, + .start_context_switch = xen_start_context_switch, .end_context_switch = xen_end_context_switch, }, }; |