[Qemu-devel] [PATCH 10/11] escc: avoid structure holes spotted by pahole

[Blue Swirl]

Edited report from pahole on amd64 host:
struct ChannelState {
...
        ChnType                    type;                 /*    32     4 */

        /* XXX 4 bytes hole, try to pack */
...
        uint8_t                    rregs[16];            /*    66    16 */

        /* XXX 2 bytes hole, try to pack */
...
        /* size: 392, cachelines: 7 */
        /* sum members: 382, holes: 2, sum holes: 6 */
        /* padding: 4 */
        /* last cacheline: 8 bytes */
};      /* definitions: 1 */

Fix by rearranging the structure to avoid padding.

Signed-off-by: Blue Swirl <address@hidden>
---
 hw/escc.c |    9 +++++----
 1 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/hw/escc.c b/hw/escc.c
index f6fd919..9d73d99 100644
--- a/hw/escc.c
+++ b/hw/escc.c
@@ -108,18 +108,19 @@ typedef struct {
 #define SERIAL_REGS 16
 typedef struct ChannelState {
     qemu_irq irq;
-    uint32_t reg;
     uint32_t rxint, txint, rxint_under_svc, txint_under_svc;
-    ChnID chn; // this channel, A (base+4) or B (base+0)
-    ChnType type;
     struct ChannelState *otherchn;
-    uint8_t rx, tx, wregs[SERIAL_REGS], rregs[SERIAL_REGS];
+    uint32_t reg;
+    uint8_t wregs[SERIAL_REGS], rregs[SERIAL_REGS];
     SERIOQueue queue;
     CharDriverState *chr;
     int e0_mode, led_mode, caps_lock_mode, num_lock_mode;
     int disabled;
     int clock;
     uint32_t vmstate_dummy;
+    ChnID chn; // this channel, A (base+4) or B (base+0)
+    ChnType type;
+    uint8_t rx, tx;
 } ChannelState;

 struct SerialState {
-- 
1.6.2.4

0010-escc-avoid-structure-holes-spotted-by-pahole.patch
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