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

[Andrew Cooper <andrew.cooper3@xxxxxxxxxx>]

So taking two traps when one will do is pointless.  This removes 1 of 13
VMExits on the int 0x13 hotpath.

Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
CC: Keir Fraser <keir@xxxxxxx>
---
 tools/firmware/rombios/rombios.c |    1 -
 1 file changed, 1 deletion(-)

diff --git a/tools/firmware/rombios/rombios.c b/tools/firmware/rombios/rombios.c
index a3efc61..f555747 100644
--- a/tools/firmware/rombios/rombios.c
+++ b/tools/firmware/rombios/rombios.c
@@ -2540,7 +2540,6 @@ static int await_ide(when_done,base,timeout)
   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);
     time++;
-- 
1.7.10.4


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