From mboxrd@z Thu Jan  1 00:00:00 1970
From: Daniel Vetter <daniel@ffwll.ch>
Subject: Re: [PATCH] sysfs rps test added
Date: Fri, 14 Sep 2012 20:32:36 +0200
Message-ID: <20120914183236.GG5799@phenom.ffwll.local>
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To: Ben Widawsky <ben@bwidawsk.net>
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On Fri, Sep 07, 2012 at 07:43:45PM -0700, Ben Widawsky wrote:
> Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
> ---

One small improvement would be nice:

[snip]

> +static void writeval(FILE *filp, int val)
> +{
> +	rewind(filp);
> +	fprintf(filp, "%d", val);
> +	fflush(filp);
> +}

Adding some assert here to check whether a write we expect to succeed
indeed worked, and that a write we expect to return -EINVAL indeed fails
with that error.
-Daniel

> +
> +#define fcur (readval(stuff[CUR].filp))
> +#define fmin (readval(stuff[MIN].filp))
> +#define fmax (readval(stuff[MAX].filp))
> +#define frp0 (readval(stuff[RP0].filp))
> +#define frp1 (readval(stuff[RP1].filp))
> +#define frpn (readval(stuff[RPn].filp))
> +
> +static void setfreq(int val)
> +{
> +	writeval(stuff[MIN].filp, val);
> +	writeval(stuff[MAX].filp, val);
> +}
> +
> +static void checkit(void)
> +{
> +	restore_assert(fmin <= fmax);
> +	restore_assert(fcur <= fmax);
> +	restore_assert(fmin <= fcur);
> +	restore_assert(frpn <= fmin);
> +	restore_assert(fmax <= frp0);
> +	restore_assert(frp1 <= frp0);
> +	restore_assert(frpn <= frp1);
> +	restore_assert(frp0 != 0);
> +	restore_assert(frp1 != 0);
> +}
> +
> +static void dumpit(void)
> +{
> +	struct junk *junk = stuff;
> +	do {
> +		printf("gt frequency %s (MHz):  %d\n", junk->name, readval(junk->filp));
> +		junk++;
> +	} while(junk->name != NULL);
> +
> +	printf("\n");
> +}
> +
> +
> +int main(int argc, char *argv[])
> +{
> +	const int device = drm_get_card(0);
> +	struct junk *junk = stuff;
> +	int fd, ret;
> +
> +	if (argc > 1)
> +		verbose++;
> +
> +	/* Use drm_open_any to verify device existence */
> +	fd = drm_open_any();
> +	close(fd);
> +
> +	do {
> +		int val = -1;
> +		char *path;
> +		ret = asprintf(&path, sysfs_base_path, device, junk->name);
> +		assert(ret != -1);
> +		junk->filp = fopen(path, junk->mode);
> +		if (junk->filp == NULL) {
> +			fprintf(stderr, "Kernel is too old. GTFO\n");
> +			exit(77);
> +		}
> +		val = readval(junk->filp);
> +		assert(val >= 0);
> +		junk++;
> +	} while(junk->name != NULL);
> +
> +	origmin = fmin;
> +	origmax = fmax;
> +
> +	if (verbose)
> +		printf("Original min = %d\nOriginal max = %d\n", origmin, origmax);
> +
> +	if (verbose)
> +		dumpit();
> +
> +	checkit();
> +	setfreq(fmin);
> +	if (verbose)
> +		dumpit();
> +	restore_assert(fcur == fmin);
> +	setfreq(fmax);
> +	if (verbose)
> +		dumpit();
> +	restore_assert(fcur == fmax);
> +	checkit();
> +
> +	/* And some errors */
> +	writeval(stuff[MIN].filp, frpn - 1);
> +	writeval(stuff[MAX].filp, frp0 + 1000);
> +	checkit();
> +
> +	writeval(stuff[MIN].filp, fmax + 1000);
> +	writeval(stuff[MAX].filp, fmin - 1);
> +	checkit();
> +
> +	writeval(stuff[MIN].filp, origmin);
> +	writeval(stuff[MAX].filp, origmax);
> +
> +	exit(EXIT_SUCCESS);
> +}
> -- 
> 1.7.12
> 
> _______________________________________________
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> Intel-gfx@lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/intel-gfx

-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch