Messages in this thread Patch in this message | | | Date | Tue, 12 May 2020 23:01:36 +0200 | From | Thomas Gleixner <> | Subject | [patch V5 37/38] x86/entry: Move paranoid irq tracing out of ASM code |
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Signed-off-by: Thomas Gleixner <tglx@linutronix.de> --- arch/x86/entry/entry_64.S | 13 ------------- arch/x86/kernel/nmi.c | 3 +++ 2 files changed, 3 insertions(+), 13 deletions(-)
--- a/arch/x86/entry/entry_64.S +++ b/arch/x86/entry/entry_64.S @@ -16,7 +16,6 @@ * * Some macro usage: * - SYM_FUNC_START/END:Define functions in the symbol table. - * - TRACE_IRQ_*: Trace hardirq state for lock debugging. * - idtentry: Define exception entry points. */ #include <linux/linkage.h> @@ -107,11 +106,6 @@ SYM_CODE_END(native_usergs_sysret64) SYM_CODE_START(entry_SYSCALL_64) UNWIND_HINT_EMPTY - /* - * Interrupts are off on entry. - * We do not frame this tiny irq-off block with TRACE_IRQS_OFF/ON, - * it is too small to ever cause noticeable irq latency. - */ swapgs /* tss.sp2 is scratch space. */ @@ -462,8 +456,6 @@ SYM_CODE_START(\asmsym) UNWIND_HINT_REGS - TRACE_IRQS_OFF - movq %rsp, %rdi /* pt_regs pointer */ .if \vector == X86_TRAP_DB @@ -881,17 +873,13 @@ SYM_CODE_END(paranoid_entry) */ SYM_CODE_START_LOCAL(paranoid_exit) UNWIND_HINT_REGS - DISABLE_INTERRUPTS(CLBR_ANY) - TRACE_IRQS_OFF testl %ebx, %ebx /* swapgs needed? */ jnz .Lparanoid_exit_no_swapgs - TRACE_IRQS_IRETQ /* Always restore stashed CR3 value (see paranoid_entry) */ RESTORE_CR3 scratch_reg=%rbx save_reg=%r14 SWAPGS_UNSAFE_STACK jmp restore_regs_and_return_to_kernel .Lparanoid_exit_no_swapgs: - TRACE_IRQS_IRETQ /* Always restore stashed CR3 value (see paranoid_entry) */ RESTORE_CR3 scratch_reg=%rbx save_reg=%r14 jmp restore_regs_and_return_to_kernel @@ -1292,7 +1280,6 @@ SYM_CODE_START(asm_exc_nmi) call paranoid_entry UNWIND_HINT_REGS - /* paranoidentry exc_nmi(), 0; without TRACE_IRQS_OFF */ movq %rsp, %rdi movq $-1, %rsi call exc_nmi --- a/arch/x86/kernel/nmi.c +++ b/arch/x86/kernel/nmi.c @@ -334,6 +334,7 @@ static noinstr void default_do_nmi(struc __this_cpu_write(last_nmi_rip, regs->ip); instrumentation_begin(); + trace_hardirqs_off_prepare(); ftrace_nmi_enter(); handled = nmi_handle(NMI_LOCAL, regs); @@ -422,6 +423,8 @@ static noinstr void default_do_nmi(struc out: ftrace_nmi_exit(); + if (regs->flags & X86_EFLAGS_IF) + trace_hardirqs_on_prepare(); instrumentation_end(); }
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