Commit 64959e2d authored by Corey Minyard's avatar Corey Minyard Committed by Linus Torvalds
Browse files

ipmi: convert locked counters to atomics in the system interface 



Atomics are faster and neater than locked counters.

Signed-off-by: default avatarCorey Minyard <cminyard@mvista.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 73f2bdb9

drivers/char/ipmi/ipmi_si_intf.c

+66 −74
Original line number Diff line number Diff line
@@ -120,6 +120,27 @@ static struct device_driver ipmi_driver = 
	.bus = &platform_bus_type

};





/*

 * Indexes into stats[] in smi_info below.

 */



#define SI_STAT_short_timeouts		0

#define SI_STAT_long_timeouts		1

#define SI_STAT_timeout_restarts	2

#define SI_STAT_idles			3

#define SI_STAT_interrupts		4

#define SI_STAT_attentions		5

#define SI_STAT_flag_fetches		6

#define SI_STAT_hosed_count		7

#define SI_STAT_complete_transactions	8

#define SI_STAT_events			9

#define SI_STAT_watchdog_pretimeouts	10

#define SI_STAT_incoming_messages	11



/* If you add a stat, you must update this value. */

#define SI_NUM_STATS			12



struct smi_info

{

	int                    intf_num;
@@ -216,25 +237,18 @@ struct smi_info 
	unsigned char slave_addr;



	/* Counters and things for the proc filesystem. */

	spinlock_t count_lock;

	unsigned long short_timeouts;

	unsigned long long_timeouts;

	unsigned long timeout_restarts;

	unsigned long idles;

	unsigned long interrupts;

	unsigned long attentions;

	unsigned long flag_fetches;

	unsigned long hosed_count;

	unsigned long complete_transactions;

	unsigned long events;

	unsigned long watchdog_pretimeouts;

	unsigned long incoming_messages;

	atomic_t stats[SI_NUM_STATS];



        struct task_struct *thread;



	struct list_head link;

};



#define smi_inc_stat(smi, stat) \

	atomic_inc(&(smi)->stats[SI_STAT_ ## stat])

#define smi_get_stat(smi, stat) \

	((unsigned int) atomic_read(&(smi)->stats[SI_STAT_ ## stat]))



#define SI_MAX_PARMS 4



static int force_kipmid[SI_MAX_PARMS];
@@ -398,9 +412,7 @@ static void handle_flags(struct smi_info *smi_info) 
 retry:

	if (smi_info->msg_flags & WDT_PRE_TIMEOUT_INT) {

		/* Watchdog pre-timeout */

		spin_lock(&smi_info->count_lock);

		smi_info->watchdog_pretimeouts++;

		spin_unlock(&smi_info->count_lock);

		smi_inc_stat(smi_info, watchdog_pretimeouts);



		start_clear_flags(smi_info);

		smi_info->msg_flags &= ~WDT_PRE_TIMEOUT_INT;
@@ -545,9 +557,7 @@ static void handle_transaction_done(struct smi_info *smi_info) 
			smi_info->msg_flags &= ~EVENT_MSG_BUFFER_FULL;

			handle_flags(smi_info);

		} else {

			spin_lock(&smi_info->count_lock);

			smi_info->events++;

			spin_unlock(&smi_info->count_lock);

			smi_inc_stat(smi_info, events);



			/* Do this before we deliver the message

			   because delivering the message releases the
@@ -581,9 +591,7 @@ static void handle_transaction_done(struct smi_info *smi_info) 
			smi_info->msg_flags &= ~RECEIVE_MSG_AVAIL;

			handle_flags(smi_info);

		} else {

			spin_lock(&smi_info->count_lock);

			smi_info->incoming_messages++;

			spin_unlock(&smi_info->count_lock);

			smi_inc_stat(smi_info, incoming_messages);



			/* Do this before we deliver the message

			   because delivering the message releases the
@@ -700,18 +708,14 @@ static enum si_sm_result smi_event_handler(struct smi_info *smi_info, 


	if (si_sm_result == SI_SM_TRANSACTION_COMPLETE)

	{

		spin_lock(&smi_info->count_lock);

		smi_info->complete_transactions++;

		spin_unlock(&smi_info->count_lock);

		smi_inc_stat(smi_info, complete_transactions);



		handle_transaction_done(smi_info);

		si_sm_result = smi_info->handlers->event(smi_info->si_sm, 0);

	}

	else if (si_sm_result == SI_SM_HOSED)

	{

		spin_lock(&smi_info->count_lock);

		smi_info->hosed_count++;

		spin_unlock(&smi_info->count_lock);

		smi_inc_stat(smi_info, hosed_count);



		/* Do the before return_hosed_msg, because that

		   releases the lock. */
@@ -733,9 +737,7 @@ static enum si_sm_result smi_event_handler(struct smi_info *smi_info, 
	{

		unsigned char msg[2];



		spin_lock(&smi_info->count_lock);

		smi_info->attentions++;

		spin_unlock(&smi_info->count_lock);

		smi_inc_stat(smi_info, attentions);



		/* Got a attn, send down a get message flags to see

                   what's causing it.  It would be better to handle
@@ -753,9 +755,7 @@ static enum si_sm_result smi_event_handler(struct smi_info *smi_info, 


	/* If we are currently idle, try to start the next message. */

	if (si_sm_result == SI_SM_IDLE) {

		spin_lock(&smi_info->count_lock);

		smi_info->idles++;

		spin_unlock(&smi_info->count_lock);

		smi_inc_stat(smi_info, idles);



		si_sm_result = start_next_msg(smi_info);

		if (si_sm_result != SI_SM_IDLE)
@@ -945,23 +945,17 @@ static void smi_timeout(unsigned long data) 
	if ((smi_info->irq) && (!smi_info->interrupt_disabled)) {

		/* Running with interrupts, only do long timeouts. */

		smi_info->si_timer.expires = jiffies + SI_TIMEOUT_JIFFIES;

		spin_lock_irqsave(&smi_info->count_lock, flags);

		smi_info->long_timeouts++;

		spin_unlock_irqrestore(&smi_info->count_lock, flags);

		smi_inc_stat(smi_info, long_timeouts);

		goto do_add_timer;

	}



	/* If the state machine asks for a short delay, then shorten

           the timer timeout. */

	if (smi_result == SI_SM_CALL_WITH_DELAY) {

		spin_lock_irqsave(&smi_info->count_lock, flags);

		smi_info->short_timeouts++;

		spin_unlock_irqrestore(&smi_info->count_lock, flags);

		smi_inc_stat(smi_info, short_timeouts);

		smi_info->si_timer.expires = jiffies + 1;

	} else {

		spin_lock_irqsave(&smi_info->count_lock, flags);

		smi_info->long_timeouts++;

		spin_unlock_irqrestore(&smi_info->count_lock, flags);

		smi_inc_stat(smi_info, long_timeouts);

		smi_info->si_timer.expires = jiffies + SI_TIMEOUT_JIFFIES;

	}
@@ -979,9 +973,7 @@ static irqreturn_t si_irq_handler(int irq, void *data) 


	spin_lock_irqsave(&(smi_info->si_lock), flags);



	spin_lock(&smi_info->count_lock);

	smi_info->interrupts++;

	spin_unlock(&smi_info->count_lock);

	smi_inc_stat(smi_info, interrupts);



#ifdef DEBUG_TIMING

	do_gettimeofday(&t);
@@ -1765,9 +1757,7 @@ static u32 ipmi_acpi_gpe(void *context) 


	spin_lock_irqsave(&(smi_info->si_lock), flags);



	spin_lock(&smi_info->count_lock);

	smi_info->interrupts++;

	spin_unlock(&smi_info->count_lock);

	smi_inc_stat(smi_info, interrupts);



#ifdef DEBUG_TIMING

	do_gettimeofday(&t);
@@ -2405,30 +2395,30 @@ static int stat_file_read_proc(char *page, char **start, off_t off, 


	out += sprintf(out, "interrupts_enabled:    %d\n",

		       smi->irq && !smi->interrupt_disabled);

	out += sprintf(out, "short_timeouts:        %ld\n",

		       smi->short_timeouts);

	out += sprintf(out, "long_timeouts:         %ld\n",

		       smi->long_timeouts);

	out += sprintf(out, "timeout_restarts:      %ld\n",

		       smi->timeout_restarts);

	out += sprintf(out, "idles:                 %ld\n",

		       smi->idles);

	out += sprintf(out, "interrupts:            %ld\n",

		       smi->interrupts);

	out += sprintf(out, "attentions:            %ld\n",

		       smi->attentions);

	out += sprintf(out, "flag_fetches:          %ld\n",

		       smi->flag_fetches);

	out += sprintf(out, "hosed_count:           %ld\n",

		       smi->hosed_count);

	out += sprintf(out, "complete_transactions: %ld\n",

		       smi->complete_transactions);

	out += sprintf(out, "events:                %ld\n",

		       smi->events);

	out += sprintf(out, "watchdog_pretimeouts:  %ld\n",

		       smi->watchdog_pretimeouts);

	out += sprintf(out, "incoming_messages:     %ld\n",

		       smi->incoming_messages);

	out += sprintf(out, "short_timeouts:        %u\n",

		       smi_get_stat(smi, short_timeouts));

	out += sprintf(out, "long_timeouts:         %u\n",

		       smi_get_stat(smi, long_timeouts));

	out += sprintf(out, "timeout_restarts:      %u\n",

		       smi_get_stat(smi, timeout_restarts));

	out += sprintf(out, "idles:                 %u\n",

		       smi_get_stat(smi, idles));

	out += sprintf(out, "interrupts:            %u\n",

		       smi_get_stat(smi, interrupts));

	out += sprintf(out, "attentions:            %u\n",

		       smi_get_stat(smi, attentions));

	out += sprintf(out, "flag_fetches:          %u\n",

		       smi_get_stat(smi, flag_fetches));

	out += sprintf(out, "hosed_count:           %u\n",

		       smi_get_stat(smi, hosed_count));

	out += sprintf(out, "complete_transactions: %u\n",

		       smi_get_stat(smi, complete_transactions));

	out += sprintf(out, "events:                %u\n",

		       smi_get_stat(smi, events));

	out += sprintf(out, "watchdog_pretimeouts:  %u\n",

		       smi_get_stat(smi, watchdog_pretimeouts));

	out += sprintf(out, "incoming_messages:     %u\n",

		       smi_get_stat(smi, incoming_messages));



	return out - page;

}
@@ -2676,6 +2666,7 @@ static int is_new_interface(struct smi_info *info) 
static int try_smi_init(struct smi_info *new_smi)

{

	int rv;

	int i;



	if (new_smi->addr_source) {

		printk(KERN_INFO "ipmi_si: Trying %s-specified %s state"
@@ -2738,7 +2729,6 @@ static int try_smi_init(struct smi_info *new_smi) 


	spin_lock_init(&(new_smi->si_lock));

	spin_lock_init(&(new_smi->msg_lock));

	spin_lock_init(&(new_smi->count_lock));



	/* Do low-level detection first. */

	if (new_smi->handlers->detect(new_smi->si_sm)) {
@@ -2767,6 +2757,8 @@ static int try_smi_init(struct smi_info *new_smi) 
	new_smi->curr_msg = NULL;

	atomic_set(&new_smi->req_events, 0);

	new_smi->run_to_completion = 0;

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

		atomic_set(&new_smi->stats[i], 0);



	new_smi->interrupt_disabled = 0;

	atomic_set(&new_smi->stop_operation, 0);