[Intel-gfx] [PATCH igt] igt: Add basic framework for GVT-g testing

[Wang, Zhi A]

> -----Original Message-----
> From: Chris Wilson [mailto:chris at chris-wilson.co.uk]
> Sent: Tuesday, June 21, 2016 2:55 PM
> To: intel-gfx at lists.freedesktop.org
> Cc: Wang, Zhi A <zhi.a.wang at intel.com>
> Subject: Re: [PATCH igt] igt: Add basic framework for GVT-g testing
> 
> On Tue, Jun 21, 2016 at 12:36:06PM +0100, Chris Wilson wrote:
> > +static bool is_gvt_enabled(void)
> > +{
> > +	FILE *file;
> > +	int value;
> > +	bool enabled = false;
> > +
> > +	file = fopen("/sys/module/i915/parameters/enable_gvt", "r");
> > +	if (!file)
> > +		return false;
> > +
> > +	if (fscanf(file, "%d", &value) == 1)
> > +		enabled = value;
> > +	fclose(file);
> > +
> > +	errno = 0;
> > +	return enabled;
> > +}
> > +
> > +static void unbind_fbcon(void)
> > +{
> > +	char buf[128];
> > +	const char *path = "/sys/class/vtconsole";
> > +	DIR *dir;
> > +	struct dirent *vtcon;
> > +
> > +	dir = opendir(path);
> > +	if (!dir)
> > +		return;
> > +
> > +	while ((vtcon = readdir(dir))) {
> > +		int fd, len;
> > +
> > +		if (strncmp(vtcon->d_name, "vtcon", 5))
> > +			continue;
> > +
> > +		sprintf(buf, "%s/%s/name", path, vtcon->d_name);
> > +		fd = open(buf, O_RDONLY);
> > +		if (fd < 0)
> > +			continue;
> > +
> > +		len = read(fd, buf, sizeof(buf) - 1);
> > +		close(fd);
> > +		if (len >= 0)
> > +			buf[len] = '\0';
> > +
> > +		if (strstr(buf, "frame buffer device")) {
> > +			sprintf(buf, "%s/%s/bind", path, vtcon->d_name);
> > +			fd = open(buf, O_WRONLY);
> > +			if (fd != -1) {
> > +				buf[0] = '1';
> > +				buf[1] = '\n';
> > +				write(fd, buf, 2);
> > +				close(fd);
> > +			}
> > +			break;
> > +		}
> > +	}
> > +	closedir(dir);
> > +}
> > +
> > +static void unload_i915(void)
> > +{
> > +	unbind_fbcon();
> > +	/* pkill alsact */
> > +
> > +	system("/sbin/modprobe -s -r i915"); }
> > +
> > +bool igt_gvt_load_module(void)
> > +{
> > +	if (is_gvt_enabled())
> > +		return true;
> > +
> > +	unload_i915();
> > +	system("/sbin/modprobe -s i915 enable_gvt=1");
> > +
> > +	return is_gvt_enabled();
> 
> Would it be safe to put igt_gvt_unload_module() into an exit handler?
> 
Would you mind to elaborate your concern here? I assume you want to register igt_gvt_unload_module() via atexit(). :D
> > +}
> > +
> > +void igt_gvt_unload_module(void)
> > +{
> > +	if (!is_gvt_enabled())
> > +		return;
> > +
> > +	unload_i915();
> > +	system("/sbin/modprobe -s i915 enable_gvt=0");
> > +
> > +	igt_assert(!is_gvt_enabled());
> > +}
> 
> --
> Chris Wilson, Intel Open Source Technology Centre