diff mbox

dec: tulip: de4x5: Replace mdelay with usleep_range in de4x5_hw_init

Message ID 1523412054-2108-1-git-send-email-baijiaju1990@gmail.com (mailing list archive)
State Awaiting Upstream, archived
Headers show

Commit Message

Jia-Ju Bai April 11, 2018, 2 a.m. UTC
de4x5_hw_init() is never called in atomic context.

de4x5_hw_init() is only called by de4x5_pci_probe(), which is only 
set as ".probe" in struct pci_driver.

Despite never getting called from atomic context, de4x5_hw_init() 
calls mdelay() to busily wait.
This is not necessary and can be replaced with usleep_range() to 
avoid busy waiting.

This is found by a static analysis tool named DCNS written by myself.
And I also manually check it.

Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
---
 drivers/net/ethernet/dec/tulip/de4x5.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

kernel test robot April 11, 2018, 2:58 p.m. UTC | #1
Hi Jia-Ju,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on net-next/master]
[also build test ERROR on v4.16 next-20180411]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Jia-Ju-Bai/dec-tulip-de4x5-Replace-mdelay-with-usleep_range-in-de4x5_hw_init/20180411-222527
config: i386-randconfig-x015-201814 (attached as .config)
compiler: gcc-7 (Debian 7.3.0-1) 7.3.0
reproduce:
        # save the attached .config to linux build tree
        make ARCH=i386 

All errors (new ones prefixed by >>):

   drivers/net//ethernet/dec/tulip/de4x5.c: In function 'de4x5_hw_init':
>> drivers/net//ethernet/dec/tulip/de4x5.c:1110:5: error: implicit declaration of function 'usleep'; did you mean 'ssleep'? [-Werror=implicit-function-declaration]
        usleep(10000, 11000);
        ^~~~~~
        ssleep
   cc1: some warnings being treated as errors

vim +1110 drivers/net//ethernet/dec/tulip/de4x5.c

  1091	
  1092	
  1093	static int
  1094	de4x5_hw_init(struct net_device *dev, u_long iobase, struct device *gendev)
  1095	{
  1096	    char name[DE4X5_NAME_LENGTH + 1];
  1097	    struct de4x5_private *lp = netdev_priv(dev);
  1098	    struct pci_dev *pdev = NULL;
  1099	    int i, status=0;
  1100	
  1101	    dev_set_drvdata(gendev, dev);
  1102	
  1103	    /* Ensure we're not sleeping */
  1104	    if (lp->bus == EISA) {
  1105		outb(WAKEUP, PCI_CFPM);
  1106	    } else {
  1107		pdev = to_pci_dev (gendev);
  1108		pci_write_config_byte(pdev, PCI_CFDA_PSM, WAKEUP);
  1109	    }
> 1110	    usleep(10000, 11000);
  1111	
  1112	    RESET_DE4X5;
  1113	
  1114	    if ((inl(DE4X5_STS) & (STS_TS | STS_RS)) != 0) {
  1115		return -ENXIO;                       /* Hardware could not reset */
  1116	    }
  1117	
  1118	    /*
  1119	    ** Now find out what kind of DC21040/DC21041/DC21140 board we have.
  1120	    */
  1121	    lp->useSROM = false;
  1122	    if (lp->bus == PCI) {
  1123		PCI_signature(name, lp);
  1124	    } else {
  1125		EISA_signature(name, gendev);
  1126	    }
  1127	
  1128	    if (*name == '\0') {                     /* Not found a board signature */
  1129		return -ENXIO;
  1130	    }
  1131	
  1132	    dev->base_addr = iobase;
  1133	    printk ("%s: %s at 0x%04lx", dev_name(gendev), name, iobase);
  1134	
  1135	    status = get_hw_addr(dev);
  1136	    printk(", h/w address %pM\n", dev->dev_addr);
  1137	
  1138	    if (status != 0) {
  1139		printk("      which has an Ethernet PROM CRC error.\n");
  1140		return -ENXIO;
  1141	    } else {
  1142		skb_queue_head_init(&lp->cache.queue);
  1143		lp->cache.gepc = GEP_INIT;
  1144		lp->asBit = GEP_SLNK;
  1145		lp->asPolarity = GEP_SLNK;
  1146		lp->asBitValid = ~0;
  1147		lp->timeout = -1;
  1148		lp->gendev = gendev;
  1149		spin_lock_init(&lp->lock);
  1150		timer_setup(&lp->timer, de4x5_ast, 0);
  1151		de4x5_parse_params(dev);
  1152	
  1153		/*
  1154		** Choose correct autosensing in case someone messed up
  1155		*/
  1156	        lp->autosense = lp->params.autosense;
  1157	        if (lp->chipset != DC21140) {
  1158	            if ((lp->chipset==DC21040) && (lp->params.autosense&TP_NW)) {
  1159	                lp->params.autosense = TP;
  1160	            }
  1161	            if ((lp->chipset==DC21041) && (lp->params.autosense&BNC_AUI)) {
  1162	                lp->params.autosense = BNC;
  1163	            }
  1164	        }
  1165		lp->fdx = lp->params.fdx;
  1166		sprintf(lp->adapter_name,"%s (%s)", name, dev_name(gendev));
  1167	
  1168		lp->dma_size = (NUM_RX_DESC + NUM_TX_DESC) * sizeof(struct de4x5_desc);
  1169	#if defined(__alpha__) || defined(__powerpc__) || defined(CONFIG_SPARC) || defined(DE4X5_DO_MEMCPY)
  1170		lp->dma_size += RX_BUFF_SZ * NUM_RX_DESC + DE4X5_ALIGN;
  1171	#endif
  1172		lp->rx_ring = dma_alloc_coherent(gendev, lp->dma_size,
  1173						 &lp->dma_rings, GFP_ATOMIC);
  1174		if (lp->rx_ring == NULL) {
  1175		    return -ENOMEM;
  1176		}
  1177	
  1178		lp->tx_ring = lp->rx_ring + NUM_RX_DESC;
  1179	
  1180		/*
  1181		** Set up the RX descriptor ring (Intels)
  1182		** Allocate contiguous receive buffers, long word aligned (Alphas)
  1183		*/
  1184	#if !defined(__alpha__) && !defined(__powerpc__) && !defined(CONFIG_SPARC) && !defined(DE4X5_DO_MEMCPY)
  1185		for (i=0; i<NUM_RX_DESC; i++) {
  1186		    lp->rx_ring[i].status = 0;
  1187		    lp->rx_ring[i].des1 = cpu_to_le32(RX_BUFF_SZ);
  1188		    lp->rx_ring[i].buf = 0;
  1189		    lp->rx_ring[i].next = 0;
  1190		    lp->rx_skb[i] = (struct sk_buff *) 1;     /* Dummy entry */
  1191		}
  1192	

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation
diff mbox

Patch

diff --git a/drivers/net/ethernet/dec/tulip/de4x5.c b/drivers/net/ethernet/dec/tulip/de4x5.c
index 0affee9..3fb0119 100644
--- a/drivers/net/ethernet/dec/tulip/de4x5.c
+++ b/drivers/net/ethernet/dec/tulip/de4x5.c
@@ -1107,7 +1107,7 @@  static int (*dc_infoblock[])(struct net_device *dev, u_char, u_char *) = {
 	pdev = to_pci_dev (gendev);
 	pci_write_config_byte(pdev, PCI_CFDA_PSM, WAKEUP);
     }
-    mdelay(10);
+    usleep(10000, 11000);
 
     RESET_DE4X5;