Gpu device never parsed?

[Ciflire]

Describe the bug
gamemoded -t does not look for the device set in settings, it always looks for default value which is 0

To Reproduce
Steps used to reproduce the behavior:

1. configure your gpu device to be different from 0
2. run gamemoded -t
3. get the following error ERROR: Couldn't open vendor file at /sys/class/drm/card0/device/vendor, will not apply gpu optimisations!
4. See that it's looking for card0 even if gpu device is not 0

Expected behavior
I do not expect it to pass all the tests but at least not for it to look for card 0 when specified 1

System Info (please complete the following information):

• OS and version: Nixos 24.11
• GameMode Version 1.8.1

Additional context
this is my config, generated by nix in /etc/gamemode.ini, it is found by process

[custom]
end=/nix/store/qjc7b5l019p260qv9r7w39hsap656jbl-libnotify-0.8.3/bin/notify-send 'GameMode ended'
start=/nix/store/qjc7b5l019p260qv9r7w39hsap656jbl-libnotify-0.8.3/bin/notify-send 'GameMode started'

[general]
disable_splitlock=0
igpu_desiredgov=performance
inhibit_screensaver=0
renice=10

[gpu]
apply_gpu_optimisations=accept-responsibility
gpu_device=1
nv_powermizer_mode=2

i do belive but could be wrong that you never parse this part of the config and keep it to default
i belive the device should be set here
https://github.com/FeralInteractive/gamemode/blob/master/daemon/gamemode-gpu.c#L74-L75
but this symbol leads to a reference in
https://github.com/FeralInteractive/gamemode/blob/master/daemon/gamemode-config.h#L116-L117
but i think is never implemented

[MrSn0wy]

i had the same issue.
A thing i noticed is that when it is set to 2 it does use card2, i guess for some reason it just doesn't like card1 lmao.

OS: Nixos 24.05
GameMode Version 1.8.1

[djahandarie]

Same issue, it doesn't seem to successfully read the config when gpu_device=1 but does when it's gpu_device=2.

This seems to be the relevant code for reading the config:

gamemode/daemon/gamemode-config.c

Line 803 in c54d6d4

DEFINE_CONFIG_GET(gpu_device)

gamemode/daemon/gamemode-config.c

Lines 60 to 66 in c54d6d4

	#define DEFINE_CONFIG_GET(name) \
	long config_get_##name(GameModeConfig *self) \
	{ \
	long value = 0; \
	memcpy_locked_config(self, &value, &self->values.name, sizeof(long)); \
	return value; \
	}

gamemode/daemon/gamemode-config.c

Lines 452 to 462 in c54d6d4

	static void memcpy_locked_config(GameModeConfig *self, void *dst, void *src, size_t n)
	{
	/* Take the read lock */
	pthread_rwlock_rdlock(&self->rwlock);
	/* copy the data */
	memcpy(dst, src, n);
	/* release the lock */
	pthread_rwlock_unlock(&self->rwlock);
	}

And this is the place that calls that code:

gamemode/daemon/gamemode-gpu.c

Lines 74 to 86 in c54d6d4

	new_info->device = config_get_gpu_device(config);
	/* verify device ID */
	if (new_info->device == -1) {
	LOG_ERROR(
	"Invalid gpu_device value set in configuration, will not apply "
	"optimisations!\n");
	free(new_info);
	return -1;
	}
	/* Fill in GPU vendor */
	new_info->vendor = gamemode_get_gpu_vendor(new_info->device);

And this is what ends up being 0 instead of 1:

gamemode/common/common-gpu.c

Lines 35 to 49 in c54d6d4

	enum GPUVendor gamemode_get_gpu_vendor(long device)
	{
	enum GPUVendor vendor = Vendor_Invalid;
	/* Fill in GPU vendor */
	char path[64] = { 0 };
	if (snprintf(path, 64, "/sys/class/drm/card%ld/device/vendor", device) < 0) {
	LOG_ERROR("snprintf failed, will not apply gpu optimisations!\n");
	return Vendor_Invalid;
	}
	FILE *file = fopen(path, "r");
	if (!file) {
	LOG_ERROR("Couldn't open vendor file at %s, will not apply gpu optimisations!\n", path);
	return Vendor_Invalid;
	}

ERROR: Couldn't open vendor file at /sys/class/drm/card0/device/vendor, will not apply gpu optimisations!

I can't immediately see an error here just from looking at the code, as it seems to just boil down to a memcpy followed by a snprintf. I guess someone would need to get a local build running to debug it further.

@afayaz-feral Sorry for the direct ping, would you have any guess why this function fails to work when the value is 1?

[pmarks-net]

Here's what I'm seeing:

::: Verifying GPU Optimisations
ERROR: Couldn't open vendor file at /sys/class/drm/card0/device/vendor, will not apply gpu optimisations!
ERROR: Failed to find Nvidia GPU with expected index!

The error message is from here:

gamemode/util/gpuclockctl.c

Line 118 in c54d6d4

LOG_ERROR("Failed to find Nvidia GPU with expected index!\n");

This loop doesn't use gpu_device, instead it tries every card until hitting Vendor_Invalid, which is supposed to mean "beyond the last card", but in my case card0 doesn't have a vendor file so the loop terminates early:

$ ls -l /sys/class/drm/card0/device/
total 0
lrwxrwxrwx 1 root root    0 Oct 15 16:49 driver -> ../../../bus/platform/drivers/simple-framebuffer
-rw-r--r-- 1 root root 4096 Oct 15 18:05 driver_override
drwxr-xr-x 3 root root    0 Oct 15 18:05 drm
drwxr-xr-x 3 root root    0 Oct 15 18:05 graphics
-r--r--r-- 1 root root 4096 Oct 15 18:05 modalias
drwxr-xr-x 2 root root    0 Oct 15 18:05 power
lrwxrwxrwx 1 root root    0 Oct 15 16:49 subsystem -> ../../../bus/platform
-rw-r--r-- 1 root root 4096 Oct 15 18:05 uevent

So the bug is that every card is assumed to have a /vendor file, which isn't the case for simple-framebuffer.

[elsandosgrande]

Implementing #364 would've been nice.