patchbot at xen
Aug 8, 2013, 10:22 PM
Post #1 of 1
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[xen master] rombios/ata: Reading this status register has no relevant side effects
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commit db46adf193be09e33fb1778f840cda5de91c777e
Author: Andrew Cooper <andrew.cooper3 [at] citrix>
AuthorDate: Tue Aug 6 14:48:38 2013 +0100
Commit: Ian Campbell <ian.campbell [at] citrix>
CommitDate: Thu Aug 8 12:03:16 2013 +0100
rombios/ata: Reading this status register has no relevant side effects
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 [at] citrix>
Acked-by: Keir Fraser <keir [at] xen>
---
tools/firmware/rombios/rombios.c | 1 -
1 files changed, 0 insertions(+), 1 deletions(-)
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++;
--
generated by git-patchbot for /home/xen/git/xen.git#master
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