Audio: MDRC: Restructure MDRC for effective memory allocation

This check-in attempts to decrease memory allocation overhead,
enhance cache efficiency through data locality, and lessen heap
fragmentation. Within the MDRC component, combine memory
allocations for the crossover, emphasis, and deemphasis filter
coefficients into a single block.

By streamlining memory management, the update lowers the possibility
of memory leaks.

Signed-off-by: Shriram Shastry <malladi.sastry@intel.com>

Author: ShriramShastry

src/audio/multiband_drc/multiband_drc.c

@@ -128,43 +128,70 @@ static int multiband_drc_init_coef(struct processing_module *mod, int16_t nch, u
 	comp_info(dev, "multiband_drc_init_coef(), initializing %i-way crossover",
 		  config->num_bands);
 
+	/* Combine memory allocations for crossover, emphasis, and deemphasis filter coefficients
+	 * into a single contiguous block to improve memory efficiency.
+	 * thereby reduces heap fragmentation, improves data locality for better cache
+	 * performance, and reduces overhead from separate memory allocations.
+	 */
+	size_t total_coefficients_size = sizeof(struct sof_eq_iir_biquad) *
+					 num_bands * nch * 3;
+
+	struct sof_eq_iir_biquad *coefficients_block =
+	    rzalloc(SOF_MEM_ZONE_RUNTIME, 0, SOF_MEM_CAPS_RAM,
+		    total_coefficients_size);
+
+	if (!coefficients_block) {
+		comp_err(dev, "multiband_drc_init_coef(), failed to allocate memory for coefficients");
+		return -ENOMEM;
+	}
+
+	/* Assign pointers to respective positions within the allocated memory block.
+	 * crossover starts at the beginning of the block,
+	 * emphasis follows after the crossover coefficients,
+	 * deemphasis is situated after the emphasis coefficients.
+	 * This ensures all filter coefficients are stored contiguously.
+	 */
+	crossover = coefficients_block;
+	emphasis = coefficients_block + num_bands * nch;
+	deemphasis = emphasis + num_bands * nch;
+
 	/* Crossover: collect the coef array and assign it to every channel */
-	crossover = config->crossover_coef;
 	for (ch = 0; ch < nch; ch++) {
 		ret = crossover_init_coef_ch(crossover, &state->crossover[ch],
 					     config->num_bands);
 		/* Free all previously allocated blocks in case of an error */
 		if (ret < 0) {
 			comp_err(dev,
 				 "multiband_drc_init_coef(), could not assign coeffs to ch %d", ch);
+			rfree(coefficients_block);
 			goto err;
 		}
 	}
 
 	comp_info(dev, "multiband_drc_init_coef(), initializing emphasis_eq");
 
 	/* Emphasis: collect the coef array and assign it to every channel */
-	emphasis = config->emp_coef;
 	for (ch = 0; ch < nch; ch++) {
 		ret = multiband_drc_eq_init_coef_ch(emphasis, &state->emphasis[ch]);
 		/* Free all previously allocated blocks in case of an error */
 		if (ret < 0) {
 			comp_err(dev, "multiband_drc_init_coef(), could not assign coeffs to ch %d",
 				 ch);
+			rfree(coefficients_block);
 			goto err;
 		}
 	}
 
 	comp_info(dev, "multiband_drc_init_coef(), initializing deemphasis_eq");
 
 	/* Deemphasis: collect the coef array and assign it to every channel */
-	deemphasis = config->deemp_coef;
 	for (ch = 0; ch < nch; ch++) {
 		ret = multiband_drc_eq_init_coef_ch(deemphasis, &state->deemphasis[ch]);
 		/* Free all previously allocated blocks in case of an error */
 		if (ret < 0) {
 			comp_err(dev, "multiband_drc_init_coef(), could not assign coeffs to ch %d",
 				 ch);
+			rfree(coefficients_block);
 			goto err;
 		}
 	}
@@ -177,6 +204,7 @@ static int multiband_drc_init_coef(struct processing_module *mod, int16_t nch, u
 		if (ret < 0) {
 			comp_err(dev,
 				 "multiband_drc_init_coef(), could not init pre delay buffers");
+			rfree(coefficients_block);
 			goto err;
 		}
 
@@ -191,6 +219,10 @@ static int multiband_drc_init_coef(struct processing_module *mod, int16_t nch, u
 	return 0;
 
 err:
+	/* Free allocated memory block on error */
+	if (coefficients_block)
+		rfree(coefficients_block);
+
 	multiband_drc_reset_state(state);
 	return ret;
 }
@@ -220,7 +252,6 @@ static int multiband_drc_init(struct processing_module *mod)
 	struct module_data *md = &mod->priv;
 	struct comp_dev *dev = mod->dev;
 	struct module_config *cfg = &md->cfg;
-	struct multiband_drc_comp_data *cd;
 	size_t bs = cfg->size;
 	int ret;
 
@@ -235,9 +266,13 @@ static int multiband_drc_init(struct processing_module *mod)
 		return -EINVAL;
 	}
 
-	cd = rzalloc(SOF_MEM_ZONE_RUNTIME, 0, SOF_MEM_CAPS_RAM, sizeof(*cd));
-	if (!cd)
+	/* Memory allocation for multiband_drc_comp_data */
+	struct multiband_drc_comp_data *cd = rzalloc(SOF_MEM_ZONE_RUNTIME, 0,
+						     SOF_MEM_CAPS_RAM, sizeof(*cd));
+	if (!cd) {
+		comp_err(dev, "multiband_drc_init(), allocation for multiband_drc_comp_data failed");
 		return -ENOMEM;
+	}
 
 	md->private = cd;
 	cd->multiband_drc_func = NULL;