escc: avoid structure holes spotted by pahole

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 <blauwirbel@gmail.com>

diff --git a/hw/escc.c b/hw/escc.c
index bea5873a02cddc55be2b699d51bcdc61ca9e6159..ffcd746e00c56395897d749e5bad258f9d9386e5 100644 (file)
--- 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 {