[dpdk-dev] [PATCH v6 1/2] eal: add uevent monitor for hot plug

Stephen Hemminger stephen at networkplumber.org
Mon Dec 25 19:06:32 CET 2017


On Thu,  2 Nov 2017 04:16:44 +0800
Jeff Guo <jia.guo at intel.com> wrote:

> +int
> +rte_dev_bind_driver(const char *dev_name, const char *drv_type) {

Bracket left after declaration.


> +	snprintf(drv_override_path, sizeof(drv_override_path),
> +		"/sys/bus/pci/devices/%s/driver_override", dev_name);
> +
> +	/* specify the driver for a device by writing to driver_override */
> +	drv_override_fd = open(drv_override_path, O_WRONLY);
> +	if (drv_override_fd < 0) {
> +		RTE_LOG(ERR, EAL, "Cannot open %s: %s\n",
> +			drv_override_path, strerror(errno));
> +		goto err;
> +	}


You should not have dev functions that assume PCI. Please split into common
and bus specific code.



> +static int
> +dev_uev_parse(const char *buf, struct rte_eal_uevent *event)
> +{
> +	char action[RTE_EAL_UEVENT_MSG_LEN];
> +	char subsystem[RTE_EAL_UEVENT_MSG_LEN];
> +	char dev_path[RTE_EAL_UEVENT_MSG_LEN];
> +	char pci_slot_name[RTE_EAL_UEVENT_MSG_LEN];
> +	int i = 0;
> +
> +	memset(action, 0, RTE_EAL_UEVENT_MSG_LEN);
> +	memset(subsystem, 0, RTE_EAL_UEVENT_MSG_LEN);
> +	memset(dev_path, 0, RTE_EAL_UEVENT_MSG_LEN);
> +	memset(pci_slot_name, 0, RTE_EAL_UEVENT_MSG_LEN);
> +
> +	while (i < RTE_EAL_UEVENT_MSG_LEN) {
> +		for (; i < RTE_EAL_UEVENT_MSG_LEN; i++) {
> +			if (*buf)
> +				break;
> +			buf++;
> +		}
> +		if (!strncmp(buf, "libudev", 7)) {
> +			buf += 7;
> +			i += 7;
> +			event->group = UEV_MONITOR_UDEV;
> +		}
> +		if (!strncmp(buf, "ACTION=", 7)) {
> +			buf += 7;
> +			i += 7;
> +			snprintf(action, sizeof(action), "%s", buf);

Why snprintf rather than strncpy?


> +		} else if (!strncmp(buf, "DEVPATH=", 8)) {
> +			buf += 8;
> +			i += 8;
> +			snprintf(dev_path, sizeof(dev_path), "%s", buf);
> +		} else if (!strncmp(buf, "SUBSYSTEM=", 10)) {
> +			buf += 10;
> +			i += 10;
> +			snprintf(subsystem, sizeof(subsystem), "%s", buf);
> +		} else if (!strncmp(buf, "PCI_SLOT_NAME=", 14)) {
> +			buf += 14;
> +			i += 14;
> +			snprintf(pci_slot_name, sizeof(subsystem), "%s", buf);
> +		}
> +		for (; i < RTE_EAL_UEVENT_MSG_LEN; i++) {
> +			if (*buf == '\0')
> +				break;
> +			buf++;
> +		}
> +	}
> +
> +	if (!strncmp(subsystem, "pci", 3))
> +		event->subsystem = UEV_SUBSYSTEM_PCI;
> +	if (!strncmp(action, "add", 3))
> +		event->type = RTE_EAL_DEV_EVENT_ADD;
> +	if (!strncmp(action, "remove", 6))
> +		event->type = RTE_EAL_DEV_EVENT_REMOVE;
> +	event->devname = pci_slot_name;

Why do you need to first capture the strings, then set state variables?
Instead why not update event->xxx directly?


More information about the dev mailing list