Richard B. Johnson writes:
> Actually I should be:
>
> pushl $next_address # Where to go when the call returns
> pushl $0xfffff000 # Put this on the stack
> ret # 'Return' to it (jump)
> next_address: # Were we end up after
You just killed that process' performance by causing the
return-stack branch prediction buffer to go out of sync.
It might have worked ok on a 486, but P6+ don't like it one bit.
This is also why I'm slightly unhappy about the
s/int $0x80/call <address of sysenter>/ approach, since it leads
to yet another recursion level and risk overflowing the RSB.
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This archive was generated by hypermail 2b29 : Mon Dec 23 2002 - 22:00:17 EST