ASoC: Intel: avs: Use lookup table to create modules

As reported by Nathan, when building avs driver using clang with:
  CONFIG_COMPILE_TEST=y
  CONFIG_FORTIFY_SOURCE=y
  CONFIG_KASAN=y
  CONFIG_PCI=y
  CONFIG_SOUND=y
  CONFIG_SND=y
  CONFIG_SND_SOC=y
  CONFIG_SND_SOC_INTEL_AVS=y

there are reports of too big stack use, like:
  sound/soc/intel/avs/path.c:815:18: error: stack frame size (2176) exceeds limit (2048) in 'avs_path_create' [-Werror,-Wframe-larger-than]
  struct avs_path *avs_path_create(struct avs_dev *adev, u32 dma_id,
                   ^
  1 error generated.

This is apparently caused by inlining many calls to guid_equal which
inlines fortified memcpy, using 2 size_t variables.

Instead of hardcoding many calls to guid_equal, use lookup table with
one call, this improves stack usage.

Link: https://lore.kernel.org/alsa-devel/YtlzY9aYdbS4Y3+l@dev-arch.thelio-3990X/T/
Link: https://github.com/ClangBuiltLinux/linux/issues/1642
Signed-off-by: Amadeusz Sławiński <amadeuszx.slawinski@linux.intel.com>
Reported-by: Nathan Chancellor <nathan@kernel.org>
Build-tested-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Cezary Rojewski <cezary.rojewski@intel.com>
Link: https://lore.kernel.org/r/20220722111959.2588597-1-amadeuszx.slawinski@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/sound/soc/intel/avs/path.c b/sound/soc/intel/avs/path.c
index 3d46dd5e5bc4946ed54c2a89fa17802d6750360b..ce157a8d65520a651a1165012b07a3f24f98cbd7 100644 (file)
--- a/sound/soc/intel/avs/path.c
+++ b/sound/soc/intel/avs/path.c
@@ -449,35 +449,39 @@ static int avs_modext_create(struct avs_dev *adev, struct avs_path_module *mod)
        return ret;
 }
 
+static int avs_probe_create(struct avs_dev *adev, struct avs_path_module *mod)
+{
+       dev_err(adev->dev, "Probe module can't be instantiated by topology");
+       return -EINVAL;
+}
+
+struct avs_module_create {
+       guid_t *guid;
+       int (*create)(struct avs_dev *adev, struct avs_path_module *mod);
+};
+
+static struct avs_module_create avs_module_create[] = {
+       { &AVS_MIXIN_MOD_UUID, avs_modbase_create },
+       { &AVS_MIXOUT_MOD_UUID, avs_modbase_create },
+       { &AVS_KPBUFF_MOD_UUID, avs_modbase_create },
+       { &AVS_COPIER_MOD_UUID, avs_copier_create },
+       { &AVS_MICSEL_MOD_UUID, avs_micsel_create },
+       { &AVS_MUX_MOD_UUID, avs_mux_create },
+       { &AVS_UPDWMIX_MOD_UUID, avs_updown_mix_create },
+       { &AVS_SRCINTC_MOD_UUID, avs_src_create },
+       { &AVS_AEC_MOD_UUID, avs_aec_create },
+       { &AVS_ASRC_MOD_UUID, avs_asrc_create },
+       { &AVS_INTELWOV_MOD_UUID, avs_wov_create },
+       { &AVS_PROBE_MOD_UUID, avs_probe_create },
+};
+
 static int avs_path_module_type_create(struct avs_dev *adev, struct avs_path_module *mod)
 {
        const guid_t *type = &mod->template->cfg_ext->type;
 
-       if (guid_equal(type, &AVS_MIXIN_MOD_UUID) ||
-           guid_equal(type, &AVS_MIXOUT_MOD_UUID) ||
-           guid_equal(type, &AVS_KPBUFF_MOD_UUID))
-               return avs_modbase_create(adev, mod);
-       if (guid_equal(type, &AVS_COPIER_MOD_UUID))
-               return avs_copier_create(adev, mod);
-       if (guid_equal(type, &AVS_MICSEL_MOD_UUID))
-               return avs_micsel_create(adev, mod);
-       if (guid_equal(type, &AVS_MUX_MOD_UUID))
-               return avs_mux_create(adev, mod);
-       if (guid_equal(type, &AVS_UPDWMIX_MOD_UUID))
-               return avs_updown_mix_create(adev, mod);
-       if (guid_equal(type, &AVS_SRCINTC_MOD_UUID))
-               return avs_src_create(adev, mod);
-       if (guid_equal(type, &AVS_AEC_MOD_UUID))
-               return avs_aec_create(adev, mod);
-       if (guid_equal(type, &AVS_ASRC_MOD_UUID))
-               return avs_asrc_create(adev, mod);
-       if (guid_equal(type, &AVS_INTELWOV_MOD_UUID))
-               return avs_wov_create(adev, mod);
-
-       if (guid_equal(type, &AVS_PROBE_MOD_UUID)) {
-               dev_err(adev->dev, "Probe module can't be instantiated by topology");
-               return -EINVAL;
-       }
+       for (int i = 0; i < ARRAY_SIZE(avs_module_create); i++)
+               if (guid_equal(type, avs_module_create[i].guid))
+                       return avs_module_create[i].create(adev, mod);
 
        return avs_modext_create(adev, mod);
 }