Commit ee8e765b authored by Takashi Iwai's avatar Takashi Iwai
Browse files

ALSA: hda - Revive snd_hda_get_conn_list() 



Manage the connection list cache using linked lists instead of
snd_array, and revive snd_hda_get_conn_list() again, so that we don't
have to keep the expanded values locally.
This will reduce the stack usage by recursive call of
snd_hda_get_conn_index() or parse_nid_path() of the generic parser.

The list management doesn't include any mutex protection, thus the
caller needs to take care of race appropriately.

Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
parent 9cc159c6

sound/pci/hda/hda_codec.c

+99 −65
Original line number Diff line number Diff line
@@ -334,20 +334,51 @@ int snd_hda_get_sub_nodes(struct hda_codec *codec, hda_nid_t nid, 
}

EXPORT_SYMBOL_HDA(snd_hda_get_sub_nodes);



/* connection list element */

struct hda_conn_list {

	struct list_head list;

	int len;

	hda_nid_t nid;

	hda_nid_t conns[0];

};



/* look up the cached results */

static hda_nid_t *lookup_conn_list(struct snd_array *array, hda_nid_t nid)

static struct hda_conn_list *

lookup_conn_list(struct hda_codec *codec, hda_nid_t nid)

{

	int i, len;

	for (i = 0; i < array->used; ) {

		hda_nid_t *p = snd_array_elem(array, i);

		if (nid == *p)

	struct hda_conn_list *p;

	list_for_each_entry(p, &codec->conn_list, list) {

		if (p->nid == nid)

			return p;

		len = p[1];

		i += len + 2;

	}

	return NULL;

}



static int add_conn_list(struct hda_codec *codec, hda_nid_t nid, int len,

			 const hda_nid_t *list)

{

	struct hda_conn_list *p;



	p = kmalloc(sizeof(*p) + len * sizeof(hda_nid_t), GFP_KERNEL);

	if (!p)

		return -ENOMEM;

	p->len = len;

	p->nid = nid;

	memcpy(p->conns, list, len * sizeof(hda_nid_t));

	list_add(&p->list, &codec->conn_list);

	return 0;

}



static void remove_conn_list(struct hda_codec *codec)

{

	while (!list_empty(&codec->conn_list)) {

		struct hda_conn_list *p;

		p = list_first_entry(&codec->conn_list, typeof(*p), list);

		list_del(&p->list);

		kfree(p);

	}

}



/* read the connection and add to the cache */

static int read_and_add_raw_conns(struct hda_codec *codec, hda_nid_t nid)

{
@@ -360,6 +391,49 @@ static int read_and_add_raw_conns(struct hda_codec *codec, hda_nid_t nid) 
	return snd_hda_override_conn_list(codec, nid, len, list);

}



/**

 * snd_hda_get_conn_list - get connection list

 * @codec: the HDA codec

 * @nid: NID to parse

 * @len: number of connection list entries

 * @listp: the pointer to store NID list

 *

 * Parses the connection list of the given widget and stores the pointer

 * to the list of NIDs.

 *

 * Returns the number of connections, or a negative error code.

 *

 * Note that the returned pointer isn't protected against the list

 * modification.  If snd_hda_override_conn_list() might be called

 * concurrently, protect with a mutex appropriately.

 */

int snd_hda_get_conn_list(struct hda_codec *codec, hda_nid_t nid,

			  const hda_nid_t **listp)

{

	bool added = false;



	for (;;) {

		int err;

		const struct hda_conn_list *p;



		/* if the connection-list is already cached, read it */

		p = lookup_conn_list(codec, nid);

		if (p) {

			if (listp)

				*listp = p->conns;

			return p->len;

		}

		if (snd_BUG_ON(added))

			return -EINVAL;



		err = read_and_add_raw_conns(codec, nid);

		if (err < 0)

			return err;

		added = true;

	}

}

EXPORT_SYMBOL_HDA(snd_hda_get_conn_list);



/**

 * snd_hda_get_connections - copy connection list

 * @codec: the HDA codec
@@ -375,39 +449,20 @@ static int read_and_add_raw_conns(struct hda_codec *codec, hda_nid_t nid) 
int snd_hda_get_connections(struct hda_codec *codec, hda_nid_t nid,

			    hda_nid_t *conn_list, int max_conns)

{

	struct snd_array *array = &codec->conn_lists;

	int len;

	hda_nid_t *p;

	bool added = false;

	const hda_nid_t *list;

	int len = snd_hda_get_conn_list(codec, nid, &list);



 again:

	mutex_lock(&codec->hash_mutex);

	len = -1;

	/* if the connection-list is already cached, read it */

	p = lookup_conn_list(array, nid);

	if (p) {

		len = p[1];

		if (conn_list && len > max_conns) {

	if (len > 0 && conn_list) {

		if (len > max_conns) {

			snd_printk(KERN_ERR "hda_codec: "

				   "Too many connections %d for NID 0x%x\n",

				   len, nid);

			mutex_unlock(&codec->hash_mutex);

			return -EINVAL;

		}

		if (conn_list && len)

			memcpy(conn_list, p + 2, len * sizeof(hda_nid_t));

		memcpy(conn_list, list, len * sizeof(hda_nid_t));

	}

	mutex_unlock(&codec->hash_mutex);

	if (len >= 0)

		return len;

	if (snd_BUG_ON(added))

		return -EINVAL;



	len = read_and_add_raw_conns(codec, nid);

	if (len < 0)

	return len;

	added = true;

	goto again;

}

EXPORT_SYMBOL_HDA(snd_hda_get_connections);
@@ -519,15 +574,6 @@ int snd_hda_get_raw_connections(struct hda_codec *codec, hda_nid_t nid, 
	return conns;

}



static bool add_conn_list(struct snd_array *array, hda_nid_t nid)

{

	hda_nid_t *p = snd_array_new(array);

	if (!p)

		return false;

	*p = nid;

	return true;

}



/**

 * snd_hda_override_conn_list - add/modify the connection-list to cache

 * @codec: the HDA codec
@@ -543,28 +589,15 @@ static bool add_conn_list(struct snd_array *array, hda_nid_t nid) 
int snd_hda_override_conn_list(struct hda_codec *codec, hda_nid_t nid, int len,

			       const hda_nid_t *list)

{

	struct snd_array *array = &codec->conn_lists;

	hda_nid_t *p;

	int i, old_used;

	struct hda_conn_list *p;



	mutex_lock(&codec->hash_mutex);

	p = lookup_conn_list(array, nid);

	if (p)

		*p = -1; /* invalidate the old entry */



	old_used = array->used;

	if (!add_conn_list(array, nid) || !add_conn_list(array, len))

		goto error_add;

	for (i = 0; i < len; i++)

		if (!add_conn_list(array, list[i]))

			goto error_add;

	mutex_unlock(&codec->hash_mutex);

	return 0;

	p = lookup_conn_list(codec, nid);

	if (p) {

		list_del(&p->list);

		kfree(p);

	}



 error_add:

	array->used = old_used;

	mutex_unlock(&codec->hash_mutex);

	return -ENOMEM;

	return add_conn_list(codec, nid, len, list);

}

EXPORT_SYMBOL_HDA(snd_hda_override_conn_list);
@@ -582,10 +615,10 @@ EXPORT_SYMBOL_HDA(snd_hda_override_conn_list); 
int snd_hda_get_conn_index(struct hda_codec *codec, hda_nid_t mux,

			   hda_nid_t nid, int recursive)

{

	hda_nid_t conn[HDA_MAX_NUM_INPUTS];

	const hda_nid_t *conn;

	int i, nums;



	nums = snd_hda_get_connections(codec, mux, conn, ARRAY_SIZE(conn));

	nums = snd_hda_get_conn_list(codec, mux, &conn);

	for (i = 0; i < nums; i++)

		if (conn[i] == nid)

			return i;
@@ -1186,8 +1219,8 @@ static void snd_hda_codec_free(struct hda_codec *codec) 
	snd_array_free(&codec->mixers);

	snd_array_free(&codec->nids);

	snd_array_free(&codec->cvt_setups);

	snd_array_free(&codec->conn_lists);

	snd_array_free(&codec->spdif_out);

	remove_conn_list(codec);

	codec->bus->caddr_tbl[codec->addr] = NULL;

	if (codec->patch_ops.free)

		codec->patch_ops.free(codec);
@@ -1257,10 +1290,11 @@ int snd_hda_codec_new(struct hda_bus *bus, 
	snd_array_init(&codec->init_pins, sizeof(struct hda_pincfg), 16);

	snd_array_init(&codec->driver_pins, sizeof(struct hda_pincfg), 16);

	snd_array_init(&codec->cvt_setups, sizeof(struct hda_cvt_setup), 8);

	snd_array_init(&codec->conn_lists, sizeof(hda_nid_t), 64);

	snd_array_init(&codec->spdif_out, sizeof(struct hda_spdif_out), 16);

	snd_array_init(&codec->jacktbl, sizeof(struct hda_jack_tbl), 16);

	snd_array_init(&codec->verbs, sizeof(struct hda_verb *), 8);

	INIT_LIST_HEAD(&codec->conn_list);



	INIT_DELAYED_WORK(&codec->jackpoll_work, hda_jackpoll_work);



#ifdef CONFIG_PM

sound/pci/hda/hda_codec.h

+3 −1
Original line number Diff line number Diff line
@@ -831,7 +831,7 @@ struct hda_codec { 
	struct hda_cache_rec amp_cache;	/* cache for amp access */

	struct hda_cache_rec cmd_cache;	/* cache for other commands */



	struct snd_array conn_lists;	/* connection-list array */

	struct list_head conn_list;	/* linked-list of connection-list */



	struct mutex spdif_mutex;

	struct mutex control_mutex;
@@ -944,6 +944,8 @@ snd_hda_get_num_conns(struct hda_codec *codec, hda_nid_t nid) 
}

int snd_hda_get_raw_connections(struct hda_codec *codec, hda_nid_t nid,

			    hda_nid_t *conn_list, int max_conns);

int snd_hda_get_conn_list(struct hda_codec *codec, hda_nid_t nid,

			  const hda_nid_t **listp);

int snd_hda_override_conn_list(struct hda_codec *codec, hda_nid_t nid, int nums,

			  const hda_nid_t *list);

int snd_hda_get_conn_index(struct hda_codec *codec, hda_nid_t mux,

sound/pci/hda/hda_generic.c

+4 −4
Original line number Diff line number Diff line
@@ -208,7 +208,7 @@ static bool __parse_nid_path(struct hda_codec *codec, 
			     int with_aa_mix, struct nid_path *path, int depth)

{

	struct hda_gen_spec *spec = codec->spec;

	hda_nid_t conn[16];

	const hda_nid_t *conn;

	int i, nums;



	if (to_nid == spec->mixer_nid) {
@@ -217,7 +217,7 @@ static bool __parse_nid_path(struct hda_codec *codec, 
		with_aa_mix = HDA_PARSE_ALL; /* mark aa-mix is included */

	}



	nums = snd_hda_get_connections(codec, to_nid, conn, ARRAY_SIZE(conn));

	nums = snd_hda_get_conn_list(codec, to_nid, &conn);

	for (i = 0; i < nums; i++) {

		if (conn[i] != from_nid) {

			/* special case: when from_nid is 0,
@@ -481,12 +481,12 @@ static void activate_amp_in(struct hda_codec *codec, struct nid_path *path, 
			    int i, bool enable, bool add_aamix)

{

	struct hda_gen_spec *spec = codec->spec;

	hda_nid_t conn[16];

	const hda_nid_t *conn;

	int n, nums, idx;

	int type;

	hda_nid_t nid = path->path[i];



	nums = snd_hda_get_connections(codec, nid, conn, ARRAY_SIZE(conn));

	nums = snd_hda_get_conn_list(codec, nid, &conn);

	type = get_wcaps_type(get_wcaps(codec, nid));

	if (type == AC_WID_PIN ||

	    (type == AC_WID_AUD_IN && codec->single_adc_amp)) {

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