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| author | Juergen Gross <jgross@suse.com> | 2021-01-20 14:55:46 +0100 |
|---|---|---|
| committer | Borislav Petkov <bp@suse.de> | 2021-02-10 12:36:45 +0100 |
| commit | ab234a260b1f625b26cbefa93ca365b0ae66df33 (patch) | |
| tree | 3308ecacbf6f66119fb14707eb506de1ab43e027 /arch/x86/kernel | |
| parent | afd30525a659ac0ae0904f0cb4a2ca75522c3123 (diff) | |
| download | linux-ab234a260b1f625b26cbefa93ca365b0ae66df33.tar.gz linux-ab234a260b1f625b26cbefa93ca365b0ae66df33.tar.bz2 linux-ab234a260b1f625b26cbefa93ca365b0ae66df33.zip | |
x86/pv: Rework arch_local_irq_restore() to not use popf
POPF is a rather expensive operation, so don't use it for restoring
irq flags. Instead, test whether interrupts are enabled in the flags
parameter and enable interrupts via STI in that case.
This results in the restore_fl paravirt op to be no longer needed.
Suggested-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210120135555.32594-7-jgross@suse.com
Diffstat (limited to 'arch/x86/kernel')
| -rw-r--r-- | arch/x86/kernel/irqflags.S | 11 | ||||
| -rw-r--r-- | arch/x86/kernel/paravirt.c | 1 | ||||
| -rw-r--r-- | arch/x86/kernel/paravirt_patch.c | 3 |
3 files changed, 0 insertions, 15 deletions
diff --git a/arch/x86/kernel/irqflags.S b/arch/x86/kernel/irqflags.S index 0db0375235b4..8ef35063964b 100644 --- a/arch/x86/kernel/irqflags.S +++ b/arch/x86/kernel/irqflags.S @@ -13,14 +13,3 @@ SYM_FUNC_START(native_save_fl) ret SYM_FUNC_END(native_save_fl) EXPORT_SYMBOL(native_save_fl) - -/* - * void native_restore_fl(unsigned long flags) - * %eax/%rdi: flags - */ -SYM_FUNC_START(native_restore_fl) - push %_ASM_ARG1 - popf - ret -SYM_FUNC_END(native_restore_fl) -EXPORT_SYMBOL(native_restore_fl) diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c index 18560b71e717..c60222ab8ab9 100644 --- a/arch/x86/kernel/paravirt.c +++ b/arch/x86/kernel/paravirt.c @@ -320,7 +320,6 @@ struct paravirt_patch_template pv_ops = { /* Irq ops. */ .irq.save_fl = __PV_IS_CALLEE_SAVE(native_save_fl), - .irq.restore_fl = __PV_IS_CALLEE_SAVE(native_restore_fl), .irq.irq_disable = __PV_IS_CALLEE_SAVE(native_irq_disable), .irq.irq_enable = __PV_IS_CALLEE_SAVE(native_irq_enable), .irq.safe_halt = native_safe_halt, diff --git a/arch/x86/kernel/paravirt_patch.c b/arch/x86/kernel/paravirt_patch.c index 2fada2c347c9..abd27ec67397 100644 --- a/arch/x86/kernel/paravirt_patch.c +++ b/arch/x86/kernel/paravirt_patch.c @@ -25,7 +25,6 @@ struct patch_xxl { const unsigned char mmu_read_cr2[3]; const unsigned char mmu_read_cr3[3]; const unsigned char mmu_write_cr3[3]; - const unsigned char irq_restore_fl[2]; const unsigned char cpu_wbinvd[2]; const unsigned char mov64[3]; }; @@ -37,7 +36,6 @@ static const struct patch_xxl patch_data_xxl = { .mmu_read_cr2 = { 0x0f, 0x20, 0xd0 }, // mov %cr2, %[re]ax .mmu_read_cr3 = { 0x0f, 0x20, 0xd8 }, // mov %cr3, %[re]ax .mmu_write_cr3 = { 0x0f, 0x22, 0xdf }, // mov %rdi, %cr3 - .irq_restore_fl = { 0x57, 0x9d }, // push %rdi; popfq .cpu_wbinvd = { 0x0f, 0x09 }, // wbinvd .mov64 = { 0x48, 0x89, 0xf8 }, // mov %rdi, %rax }; @@ -71,7 +69,6 @@ unsigned int native_patch(u8 type, void *insn_buff, unsigned long addr, switch (type) { #ifdef CONFIG_PARAVIRT_XXL - PATCH_CASE(irq, restore_fl, xxl, insn_buff, len); PATCH_CASE(irq, save_fl, xxl, insn_buff, len); PATCH_CASE(irq, irq_enable, xxl, insn_buff, len); PATCH_CASE(irq, irq_disable, xxl, insn_buff, len); |