On Tue, Jun 21, 2016 at 12:01:02PM +0000, Wang, Zhi A wrote: > > > > -----Original Message----- > > From: Chris Wilson [mailto:chris@xxxxxxxxxxxxxxxxxx] > > Sent: Tuesday, June 21, 2016 2:55 PM > > To: intel-gfx@xxxxxxxxxxxxxxxxxxxxx > > Cc: Wang, Zhi A <zhi.a.wang@xxxxxxxxx> > > 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 Yes. I was thinking that it would be more convenient to tests to automatically cleanup and restore the previous state. However, an error path is likely to leave the module in-use during our atexit handler and so prevent us from unloading the module. Still it is one thing less to remember when writing a test case. The problem with the atexit handler is that it needs to be sigsafe. The use of fopen here could be problematic for instance. -Chris -- Chris Wilson, Intel Open Source Technology Centre _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
