From 96e540492ab54423f3693958329e095878f1f12b Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Tue, 26 Sep 2006 10:52:39 +0200 Subject: [PATCH] Fix a irqcount comment in entry.S Signed-off-by: Andi Kleen --- arch/x86_64/kernel/entry.S | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'arch') diff --git a/arch/x86_64/kernel/entry.S b/arch/x86_64/kernel/entry.S index 4fcc0ad8bbe..ea32688386f 100644 --- a/arch/x86_64/kernel/entry.S +++ b/arch/x86_64/kernel/entry.S @@ -519,7 +519,12 @@ END(stub_rt_sigreturn) testl $3,CS(%rdi) je 1f swapgs -1: incl %gs:pda_irqcount # RED-PEN should check preempt count + /* irqcount is used to check if a CPU is already on an interrupt + stack or not. While this is essentially redundant with preempt_count + it is a little cheaper to use a separate counter in the PDA + (short of moving irq_enter into assembly, which would be too + much work) */ +1: incl %gs:pda_irqcount cmoveq %gs:pda_irqstackptr,%rsp push %rbp # backlink for old unwinder /* -- cgit v1.2.3