Commit 16f31113 authored by Yum Rayan's avatar Yum Rayan Committed by Linus Torvalds
Browse files

[PATCH] serial_cs: Reduce stack usage in serial_event() 



This patch reduces the stack usage of the function serial_event() in
serial_cs from 2212 to 228.  I used a patched version of gcc 3.4.3 on i386
with -fno-unit-at-a-time disabled.

This patch is only compile tested.

Acked-by: default avatarRandy Dunlap <rddunlap@osdl.org>
Signed-off-by: default avatarYum Rayan <yum.rayan@gmail.com>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent dbcf31ba

drivers/serial/serial_cs.c

+112 −61
Original line number Diff line number Diff line
@@ -107,6 +107,13 @@ struct serial_info { 
	int			line[4];

};



struct serial_cfg_mem {

	tuple_t tuple;

	cisparse_t parse;

	u_char buf[256];

};





static void serial_config(dev_link_t * link);

static int serial_event(event_t event, int priority,

			event_callback_args_t * args);
@@ -357,14 +364,24 @@ static int simple_config(dev_link_t *link) 
	static int size_table[2] = { 8, 16 };

	client_handle_t handle = link->handle;

	struct serial_info *info = link->priv;

	tuple_t tuple;

	u_char buf[256];

	cisparse_t parse;

	cistpl_cftable_entry_t *cf = &parse.cftable_entry;

	struct serial_cfg_mem *cfg_mem;

	tuple_t *tuple;

	u_char *buf;

	cisparse_t *parse;

	cistpl_cftable_entry_t *cf;

	config_info_t config;

	int i, j, try;

	int s;



	cfg_mem = kmalloc(sizeof(struct serial_cfg_mem), GFP_KERNEL);

	if (!cfg_mem)

		return -1;



	tuple = &cfg_mem->tuple;

	parse = &cfg_mem->parse;

	cf = &parse->cftable_entry;

	buf = cfg_mem->buf;



	/* If the card is already configured, look up the port and irq */

	i = pcmcia_get_configuration_info(handle, &config);

	if ((i == CS_SUCCESS) && (config.Attributes & CONF_VALID_CLIENT)) {
@@ -377,21 +394,23 @@ static int simple_config(dev_link_t *link) 
			port = config.BasePort1 + 0x28;

			info->slave = 1;

		}

		if (info->slave)

		if (info->slave) {

			kfree(cfg_mem);

			return setup_serial(handle, info, port, config.AssignedIRQ);

		}

	}

	link->conf.Vcc = config.Vcc;



	/* First pass: look for a config entry that looks normal. */

	tuple.TupleData = (cisdata_t *) buf;

	tuple.TupleOffset = 0;

	tuple.TupleDataMax = 255;

	tuple.Attributes = 0;

	tuple.DesiredTuple = CISTPL_CFTABLE_ENTRY;

	tuple->TupleData = (cisdata_t *) buf;

	tuple->TupleOffset = 0;

	tuple->TupleDataMax = 255;

	tuple->Attributes = 0;

	tuple->DesiredTuple = CISTPL_CFTABLE_ENTRY;

	/* Two tries: without IO aliases, then with aliases */

	for (s = 0; s < 2; s++) {

		for (try = 0; try < 2; try++) {

			i = first_tuple(handle, &tuple, &parse);

			i = first_tuple(handle, tuple, parse);

			while (i != CS_NO_MORE_ITEMS) {

				if (i != CS_SUCCESS)

					goto next_entry;
@@ -409,14 +428,14 @@ static int simple_config(dev_link_t *link) 
						goto found_port;

				}

next_entry:

				i = next_tuple(handle, &tuple, &parse);

				i = next_tuple(handle, tuple, parse);

			}

		}

	}

	/* Second pass: try to find an entry that isn't picky about

	   its base address, then try to grab any standard serial port

	   address, and finally try to get any free port. */

	i = first_tuple(handle, &tuple, &parse);

	i = first_tuple(handle, tuple, parse);

	while (i != CS_NO_MORE_ITEMS) {

		if ((i == CS_SUCCESS) && (cf->io.nwin > 0) &&

		    ((cf->io.flags & CISTPL_IO_LINES_MASK) <= 3)) {
@@ -429,7 +448,7 @@ next_entry: 
					goto found_port;

			}

		}

		i = next_tuple(handle, &tuple, &parse);

		i = next_tuple(handle, tuple, parse);

	}



      found_port:
@@ -437,6 +456,7 @@ next_entry: 
		printk(KERN_NOTICE

		       "serial_cs: no usable port range found, giving up\n");

		cs_error(link->handle, RequestIO, i);

		kfree(cfg_mem);

		return -1;

	}
@@ -450,9 +470,10 @@ next_entry: 
	i = pcmcia_request_configuration(link->handle, &link->conf);

	if (i != CS_SUCCESS) {

		cs_error(link->handle, RequestConfiguration, i);

		kfree(cfg_mem);

		return -1;

	}



	kfree(cfg_mem);

	return setup_serial(handle, info, link->io.BasePort1, link->irq.AssignedIRQ);

}
@@ -460,29 +481,39 @@ static int multi_config(dev_link_t * link) 
{

	client_handle_t handle = link->handle;

	struct serial_info *info = link->priv;

	tuple_t tuple;

	u_char buf[256];

	cisparse_t parse;

	cistpl_cftable_entry_t *cf = &parse.cftable_entry;

	struct serial_cfg_mem *cfg_mem;

	tuple_t *tuple;

	u_char *buf;

	cisparse_t *parse;

	cistpl_cftable_entry_t *cf;

	config_info_t config;

	int i, base2 = 0;

	int i, rc, base2 = 0;



	cfg_mem = kmalloc(sizeof(struct serial_cfg_mem), GFP_KERNEL);

	if (!cfg_mem)

		return -1;

	tuple = &cfg_mem->tuple;

	parse = &cfg_mem->parse;

	cf = &parse->cftable_entry;

	buf = cfg_mem->buf;



	i = pcmcia_get_configuration_info(handle, &config);

	if (i != CS_SUCCESS) {

		cs_error(handle, GetConfigurationInfo, i);

		return -1;

		rc = -1;

		goto free_cfg_mem;

	}

	link->conf.Vcc = config.Vcc;



	tuple.TupleData = (cisdata_t *) buf;

	tuple.TupleOffset = 0;

	tuple.TupleDataMax = 255;

	tuple.Attributes = 0;

	tuple.DesiredTuple = CISTPL_CFTABLE_ENTRY;

	tuple->TupleData = (cisdata_t *) buf;

	tuple->TupleOffset = 0;

	tuple->TupleDataMax = 255;

	tuple->Attributes = 0;

	tuple->DesiredTuple = CISTPL_CFTABLE_ENTRY;



	/* First, look for a generic full-sized window */

	link->io.NumPorts1 = info->multi * 8;

	i = first_tuple(handle, &tuple, &parse);

	i = first_tuple(handle, tuple, parse);

	while (i != CS_NO_MORE_ITEMS) {

		/* The quad port cards have bad CIS's, so just look for a

		   window larger than 8 ports and assume it will be right */
@@ -497,14 +528,14 @@ static int multi_config(dev_link_t * link) 
			if (i == CS_SUCCESS)

				break;

		}

		i = next_tuple(handle, &tuple, &parse);

		i = next_tuple(handle, tuple, parse);

	}



	/* If that didn't work, look for two windows */

	if (i != CS_SUCCESS) {

		link->io.NumPorts1 = link->io.NumPorts2 = 8;

		info->multi = 2;

		i = first_tuple(handle, &tuple, &parse);

		i = first_tuple(handle, tuple, parse);

		while (i != CS_NO_MORE_ITEMS) {

			if ((i == CS_SUCCESS) && (cf->io.nwin == 2)) {

				link->conf.ConfigIndex = cf->index;
@@ -517,13 +548,14 @@ static int multi_config(dev_link_t * link) 
				if (i == CS_SUCCESS)

					break;

			}

			i = next_tuple(handle, &tuple, &parse);

			i = next_tuple(handle, tuple, parse);

		}

	}



	if (i != CS_SUCCESS) {

		cs_error(link->handle, RequestIO, i);

		return -1;

		rc = -1;

		goto free_cfg_mem;

	}



	i = pcmcia_request_irq(link->handle, &link->irq);
@@ -541,7 +573,8 @@ static int multi_config(dev_link_t * link) 
	i = pcmcia_request_configuration(link->handle, &link->conf);

	if (i != CS_SUCCESS) {

		cs_error(link->handle, RequestConfiguration, i);

		return -1;

		rc = -1;

		goto free_cfg_mem;

	}



	/* The Oxford Semiconductor OXCF950 cards are in fact single-port:
@@ -554,17 +587,23 @@ static int multi_config(dev_link_t * link) 
			setup_serial(handle, info, link->io.BasePort1, link->irq.AssignedIRQ);

			outb(12, base2 + 1);

		}

		return 0;

		rc = 0;

		goto free_cfg_mem;

	}



	setup_serial(handle, info, link->io.BasePort1, link->irq.AssignedIRQ);

	/* The Nokia cards are not really multiport cards */

	if (info->manfid == MANFID_NOKIA)

		return 0;

	if (info->manfid == MANFID_NOKIA) {

		rc = 0;

		goto free_cfg_mem;

	}

	for (i = 0; i < info->multi - 1; i++)

		setup_serial(handle, info, base2 + (8 * i), link->irq.AssignedIRQ);



	return 0;

		setup_serial(handle, info, base2 + (8 * i),

				link->irq.AssignedIRQ);

	rc = 0;

free_cfg_mem:

	kfree(cfg_mem);

	return rc;

}



/*======================================================================
@@ -579,39 +618,49 @@ void serial_config(dev_link_t * link) 
{

	client_handle_t handle = link->handle;

	struct serial_info *info = link->priv;

	tuple_t tuple;

	u_short buf[128];

	cisparse_t parse;

	cistpl_cftable_entry_t *cf = &parse.cftable_entry;

	struct serial_cfg_mem *cfg_mem;

	tuple_t *tuple;

	u_char *buf;

	cisparse_t *parse;

	cistpl_cftable_entry_t *cf;

	int i, last_ret, last_fn;



	DEBUG(0, "serial_config(0x%p)\n", link);



	tuple.TupleData = (cisdata_t *) buf;

	tuple.TupleOffset = 0;

	tuple.TupleDataMax = 255;

	tuple.Attributes = 0;

	cfg_mem = kmalloc(sizeof(struct serial_cfg_mem), GFP_KERNEL);

	if (!cfg_mem)

		goto failed;



	tuple = &cfg_mem->tuple;

	parse = &cfg_mem->parse;

	cf = &parse->cftable_entry;

	buf = cfg_mem->buf;



	tuple->TupleData = (cisdata_t *) buf;

	tuple->TupleOffset = 0;

	tuple->TupleDataMax = 255;

	tuple->Attributes = 0;

	/* Get configuration register information */

	tuple.DesiredTuple = CISTPL_CONFIG;

	last_ret = first_tuple(handle, &tuple, &parse);

	tuple->DesiredTuple = CISTPL_CONFIG;

	last_ret = first_tuple(handle, tuple, parse);

	if (last_ret != CS_SUCCESS) {

		last_fn = ParseTuple;

		goto cs_failed;

	}

	link->conf.ConfigBase = parse.config.base;

	link->conf.Present = parse.config.rmask[0];

	link->conf.ConfigBase = parse->config.base;

	link->conf.Present = parse->config.rmask[0];



	/* Configure card */

	link->state |= DEV_CONFIG;



	/* Is this a compliant multifunction card? */

	tuple.DesiredTuple = CISTPL_LONGLINK_MFC;

	tuple.Attributes = TUPLE_RETURN_COMMON | TUPLE_RETURN_LINK;

	info->multi = (first_tuple(handle, &tuple, &parse) == CS_SUCCESS);

	tuple->DesiredTuple = CISTPL_LONGLINK_MFC;

	tuple->Attributes = TUPLE_RETURN_COMMON | TUPLE_RETURN_LINK;

	info->multi = (first_tuple(handle, tuple, parse) == CS_SUCCESS);



	/* Is this a multiport card? */

	tuple.DesiredTuple = CISTPL_MANFID;

	if (first_tuple(handle, &tuple, &parse) == CS_SUCCESS) {

	tuple->DesiredTuple = CISTPL_MANFID;

	if (first_tuple(handle, tuple, parse) == CS_SUCCESS) {

		info->manfid = le16_to_cpu(buf[0]);

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

			if ((info->manfid == multi_id[i].manfid) &&
@@ -623,13 +672,13 @@ void serial_config(dev_link_t * link) 


	/* Another check for dual-serial cards: look for either serial or

	   multifunction cards that ask for appropriate IO port ranges */

	tuple.DesiredTuple = CISTPL_FUNCID;

	tuple->DesiredTuple = CISTPL_FUNCID;

	if ((info->multi == 0) &&

	    ((first_tuple(handle, &tuple, &parse) != CS_SUCCESS) ||

	     (parse.funcid.func == CISTPL_FUNCID_MULTI) ||

	     (parse.funcid.func == CISTPL_FUNCID_SERIAL))) {

		tuple.DesiredTuple = CISTPL_CFTABLE_ENTRY;

		if (first_tuple(handle, &tuple, &parse) == CS_SUCCESS) {

	    ((first_tuple(handle, tuple, parse) != CS_SUCCESS) ||

	     (parse->funcid.func == CISTPL_FUNCID_MULTI) ||

	     (parse->funcid.func == CISTPL_FUNCID_SERIAL))) {

		tuple->DesiredTuple = CISTPL_CFTABLE_ENTRY;

		if (first_tuple(handle, tuple, parse) == CS_SUCCESS) {

			if ((cf->io.nwin == 1) && (cf->io.win[0].len % 8 == 0))

				info->multi = cf->io.win[0].len >> 3;

			if ((cf->io.nwin == 2) && (cf->io.win[0].len == 8) &&
@@ -664,6 +713,7 @@ void serial_config(dev_link_t * link) 


	link->dev = &info->node[0];

	link->state &= ~DEV_CONFIG_PENDING;

	kfree(cfg_mem);

	return;



 cs_failed:
@@ -671,6 +721,7 @@ void serial_config(dev_link_t * link) 
 failed:

	serial_remove(link);

	link->state &= ~DEV_CONFIG_PENDING;

	kfree(cfg_mem);

}



/*======================================================================

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