Re: [Xen-devel] [PATCH] xen: drop the nop() macro

[Wei Liu <wei.liu2@xxxxxxxxxx>]

On Fri, Mar 15, 2019 at 01:39:05PM +0000, Andrew Cooper wrote:
> There isn't a plausible reason to insert nops like this into code.
> 
> The sole use is in do_debug_key(), and exists to prevent the compiler
> optimising the tail of the function with 'jmp debugger_trap_fatal'
> 
> In practice, a compiler barrier suffices just as well to prevent the tailcall,
> and doesn't involve inserting unnecessary instructions.
> 
> Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>

Reviewed-by: Wei Liu <wei.liu2@xxxxxxxxxx>

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