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| author | Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> | 2009-02-18 07:46:21 (GMT) |
|---|---|---|
| committer | Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> | 2009-03-30 06:36:00 (GMT) |
| commit | b407fc57b815b2016186220baabc76cc8264206e (patch) | |
| tree | 29949f727af8b6c19fd689fa10f123ea84c03cb0 /arch/x86/kernel | |
| parent | 7fd7d83d49914f03aefffba6aee09032fcd54cce (diff) | |
| download | linux-b407fc57b815b2016186220baabc76cc8264206e.tar.xz | |
x86/paravirt: flush pending mmu updates on context switch
Impact: allow preemption during lazy mmu updates
If we're in lazy mmu mode when context switching, leave
lazy mmu mode, but remember the task's state in
TIF_LAZY_MMU_UPDATES. When we resume the task, check this
flag and re-enter lazy mmu mode if its set.
This sets things up for allowing lazy mmu mode while preemptible,
though that won't actually be active until the next change.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Diffstat (limited to 'arch/x86/kernel')
| -rw-r--r-- | arch/x86/kernel/kvm.c | 2 | ||||
| -rw-r--r-- | arch/x86/kernel/paravirt.c | 13 | ||||
| -rw-r--r-- | arch/x86/kernel/vmi_32.c | 14 |
3 files changed, 21 insertions, 8 deletions
diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index 478bca9..5d7f6e7 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -201,7 +201,7 @@ static void kvm_leave_lazy_mmu(void) struct kvm_para_state *state = kvm_para_state(); mmu_queue_flush(state); - paravirt_leave_lazy(paravirt_get_lazy_mode()); + paravirt_leave_lazy_mmu(); state->mode = paravirt_get_lazy_mode(); } diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c index 5eea954..430a0e3 100644 --- a/arch/x86/kernel/paravirt.c +++ b/arch/x86/kernel/paravirt.c @@ -252,7 +252,7 @@ static inline void enter_lazy(enum paravirt_lazy_mode mode) __get_cpu_var(paravirt_lazy_mode) = mode; } -void paravirt_leave_lazy(enum paravirt_lazy_mode mode) +static void leave_lazy(enum paravirt_lazy_mode mode) { BUG_ON(__get_cpu_var(paravirt_lazy_mode) != mode); BUG_ON(preemptible()); @@ -267,17 +267,24 @@ void paravirt_enter_lazy_mmu(void) void paravirt_leave_lazy_mmu(void) { - paravirt_leave_lazy(PARAVIRT_LAZY_MMU); + leave_lazy(PARAVIRT_LAZY_MMU); } void paravirt_enter_lazy_cpu(void) { + if (percpu_read(paravirt_lazy_mode) == PARAVIRT_LAZY_MMU) { + arch_leave_lazy_mmu_mode(); + set_thread_flag(TIF_LAZY_MMU_UPDATES); + } enter_lazy(PARAVIRT_LAZY_CPU); } void paravirt_leave_lazy_cpu(void) { - paravirt_leave_lazy(PARAVIRT_LAZY_CPU); + leave_lazy(PARAVIRT_LAZY_CPU); + + if (test_and_clear_thread_flag(TIF_LAZY_MMU_UPDATES)) + arch_enter_lazy_mmu_mode(); } enum paravirt_lazy_mode paravirt_get_lazy_mode(void) diff --git a/arch/x86/kernel/vmi_32.c b/arch/x86/kernel/vmi_32.c index 2cc4a90..950929c 100644 --- a/arch/x86/kernel/vmi_32.c +++ b/arch/x86/kernel/vmi_32.c @@ -473,16 +473,22 @@ static void vmi_enter_lazy_cpu(void) vmi_ops.set_lazy_mode(2); } +static void vmi_leave_lazy_cpu(void) +{ + vmi_ops.set_lazy_mode(0); + paravirt_leave_lazy_cpu(); +} + static void vmi_enter_lazy_mmu(void) { paravirt_enter_lazy_mmu(); vmi_ops.set_lazy_mode(1); } -static void vmi_leave_lazy(void) +static void vmi_leave_lazy_mmu(void) { - paravirt_leave_lazy(paravirt_get_lazy_mode()); vmi_ops.set_lazy_mode(0); + paravirt_leave_lazy_mmu(); } static inline int __init check_vmi_rom(struct vrom_header *rom) @@ -718,12 +724,12 @@ static inline int __init activate_vmi(void) para_wrap(pv_cpu_ops.lazy_mode.enter, vmi_enter_lazy_cpu, set_lazy_mode, SetLazyMode); - para_wrap(pv_cpu_ops.lazy_mode.leave, vmi_leave_lazy, + para_wrap(pv_cpu_ops.lazy_mode.leave, vmi_leave_lazy_cpu, set_lazy_mode, SetLazyMode); para_wrap(pv_mmu_ops.lazy_mode.enter, vmi_enter_lazy_mmu, set_lazy_mode, SetLazyMode); - para_wrap(pv_mmu_ops.lazy_mode.leave, vmi_leave_lazy, + para_wrap(pv_mmu_ops.lazy_mode.leave, vmi_leave_lazy_mmu, set_lazy_mode, SetLazyMode); /* user and kernel flush are just handled with different flags to FlushTLB */ |