From 12ec5e100f9198cd6a6be2b00e17b5399eecbaa7 Mon Sep 17 00:00:00 2001
Message-Id: <12ec5e100f9198cd6a6be2b00e17b5399eecbaa7.1312750600.git.blauwirbel@gmail.com>
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References: <54eae070f9056790fa41b468360d23cdd17503f4.1312750600.git.blauwirbel@gmail.com>
From: Blue Swirl <blauwirbel@gmail.com>
Date: Sun, 7 Aug 2011 19:43:38 +0000
Subject: [PATCH 09/11] fdc:avoid structure holes spotted by pahole
Edited report from pahole on amd64 host:
struct FDCtrl {
uint8_t version; /* 0 1 */
/* XXX 7 bytes hole, try to pack */
qemu_irq irq; /* 8 8 */
int dma_chann; /* 16 4 */
/* XXX 4 bytes hole, try to pack */
...
uint8_t status2; /* 42 1 */
/* XXX 5 bytes hole, try to pack */
uint8_t * fifo; /* 48 8 */
...
uint8_t pwrd; /* 76 1 */
/* XXX 3 bytes hole, try to pack */
int sun4m; /* 80 4 */
uint8_t num_floppies; /* 84 1 */
/* XXX 3 bytes hole, try to pack */
FDrive drives[2]; /* 88 64 */
/* --- cacheline 2 boundary (128 bytes) was 24 bytes ago --- */
int reset_sensei; /* 152 4 */
/* size: 160, cachelines: 3 */
/* sum members: 134, holes: 5, sum holes: 22 */
/* padding: 4 */
/* last cacheline: 32 bytes */
}; /* definitions: 1 */
Fix by rearranging the structure to avoid padding.
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
---
hw/fdc.c | 18 +++++++++---------
1 files changed, 9 insertions(+), 9 deletions(-)
@@ -374,13 +374,13 @@ enum {
#define FD_FORMAT_CMD(state) ((state) & FD_STATE_FORMAT)
struct FDCtrl {
- /* Controller's identification */
- uint8_t version;
- /* HW */
qemu_irq irq;
- int dma_chann;
/* Controller state */
QEMUTimer *result_timer;
+ int dma_chann;
+ /* Controller's identification */
+ uint8_t version;
+ /* HW */
uint8_t sra;
uint8_t srb;
uint8_t dor;
@@ -401,21 +401,21 @@ struct FDCtrl {
uint8_t data_dir;
uint8_t eot; /* last wanted sector */
/* States kept only to be returned back */
- /* Timers state */
- uint8_t timer0;
- uint8_t timer1;
/* precompensation */
uint8_t precomp_trk;
uint8_t config;
uint8_t lock;
/* Power down config (also with status regB access mode */
uint8_t pwrd;
- /* Sun4m quirks? */
- int sun4m;
/* Floppy drives */
uint8_t num_floppies;
+ /* Sun4m quirks? */
+ int sun4m;
FDrive drives[MAX_FD];
int reset_sensei;
+ /* Timers state */
+ uint8_t timer0;
+ uint8_t timer1;
};
typedef struct FDCtrlSysBus {
--
1.7.2.5
Edited report from pahole on amd64 host: struct FDCtrl { uint8_t version; /* 0 1 */ /* XXX 7 bytes hole, try to pack */ qemu_irq irq; /* 8 8 */ int dma_chann; /* 16 4 */ /* XXX 4 bytes hole, try to pack */ ... uint8_t status2; /* 42 1 */ /* XXX 5 bytes hole, try to pack */ uint8_t * fifo; /* 48 8 */ ... uint8_t pwrd; /* 76 1 */ /* XXX 3 bytes hole, try to pack */ int sun4m; /* 80 4 */ uint8_t num_floppies; /* 84 1 */ /* XXX 3 bytes hole, try to pack */ FDrive drives[2]; /* 88 64 */ /* --- cacheline 2 boundary (128 bytes) was 24 bytes ago --- */ int reset_sensei; /* 152 4 */ /* size: 160, cachelines: 3 */ /* sum members: 134, holes: 5, sum holes: 22 */ /* padding: 4 */ /* last cacheline: 32 bytes */ }; /* definitions: 1 */ Fix by rearranging the structure to avoid padding. Signed-off-by: Blue Swirl <blauwirbel@gmail.com> --- hw/fdc.c | 18 +++++++++--------- 1 files changed, 9 insertions(+), 9 deletions(-)