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[Xen-devel] [PATCH 3 of 5] rombios/ata: Reading this status register has no relevant side effects

So taking two traps when one will do is pointless.  This codepath is on the int
0x13 hot path, and removing it has about a 30% reduction in the number of traps
to Qemu during Win7 boot.

Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>

diff -r 59de21ca1546 -r 5e8fbfea2229 tools/firmware/rombios/rombios.c
--- a/tools/firmware/rombios/rombios.c
+++ b/tools/firmware/rombios/rombios.c
@@ -2540,7 +2540,6 @@ static int await_ide(when_done,base,time
   Bit32u time=0,last=0;
   Bit16u status;
   Bit8u result;
-  status = inb(base + ATA_CB_STAT); // for the times you're supposed to throw 
one away
   for(;;) {
     status = inb(base+ATA_CB_STAT);
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