diff options
author | Corey Minyard <minyard@acm.org> | 2005-11-07 04:00:03 -0500 |
---|---|---|
committer | Linus Torvalds <torvalds@g5.osdl.org> | 2005-11-07 10:53:44 -0500 |
commit | a9a2c44ff0a1350f8bfe3a162ecf71b1c9ce5cc2 (patch) | |
tree | ac5ffc65084b48895239e9044893ae7e0b2d91b1 /drivers/char/ipmi/ipmi_si_intf.c | |
parent | c3e7e7916ec61cf58c88af12f4db17f28cffd83a (diff) |
[PATCH] ipmi: add timer thread
We must poll for responses to commands when interrupts aren't in use. The
default poll interval is based on using a kernel timer, which varies with HZ.
For character-based interfaces like KCS and SMIC though, that can be way too
slow (>15 minutes to flash a new firmware with KCS, >20 seconds to retrieve
the sensor list).
This creates a low-priority kernel thread to poll more often. If the state
machine is idle, so is the kernel thread. But if there's an active command,
it polls quite rapidly. This decrease a firmware flash time from 15 minutes
to 1.5 minutes, and the sensor list time to 4.5 seconds, on a Dell PowerEdge
x8x system.
The timer-based polling remains, to ensure some amount of responsiveness even
under high user process CPU load.
Checking for a stopped timer at rmmod now uses atomics and del_timer_sync() to
ensure safe stoppage.
Signed-off-by: Matt Domsch <Matt_Domsch@dell.com>
Signed-off-by: Corey Minyard <minyard@acm.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'drivers/char/ipmi/ipmi_si_intf.c')
-rw-r--r-- | drivers/char/ipmi/ipmi_si_intf.c | 84 |
1 files changed, 63 insertions, 21 deletions
diff --git a/drivers/char/ipmi/ipmi_si_intf.c b/drivers/char/ipmi/ipmi_si_intf.c index d514df7c728..fa3be622ca9 100644 --- a/drivers/char/ipmi/ipmi_si_intf.c +++ b/drivers/char/ipmi/ipmi_si_intf.c | |||
@@ -126,6 +126,7 @@ struct ipmi_device_id { | |||
126 | 126 | ||
127 | struct smi_info | 127 | struct smi_info |
128 | { | 128 | { |
129 | int intf_num; | ||
129 | ipmi_smi_t intf; | 130 | ipmi_smi_t intf; |
130 | struct si_sm_data *si_sm; | 131 | struct si_sm_data *si_sm; |
131 | struct si_sm_handlers *handlers; | 132 | struct si_sm_handlers *handlers; |
@@ -193,8 +194,7 @@ struct smi_info | |||
193 | unsigned long last_timeout_jiffies; | 194 | unsigned long last_timeout_jiffies; |
194 | 195 | ||
195 | /* Used to gracefully stop the timer without race conditions. */ | 196 | /* Used to gracefully stop the timer without race conditions. */ |
196 | volatile int stop_operation; | 197 | atomic_t stop_operation; |
197 | volatile int timer_stopped; | ||
198 | 198 | ||
199 | /* The driver will disable interrupts when it gets into a | 199 | /* The driver will disable interrupts when it gets into a |
200 | situation where it cannot handle messages due to lack of | 200 | situation where it cannot handle messages due to lack of |
@@ -221,6 +221,9 @@ struct smi_info | |||
221 | unsigned long events; | 221 | unsigned long events; |
222 | unsigned long watchdog_pretimeouts; | 222 | unsigned long watchdog_pretimeouts; |
223 | unsigned long incoming_messages; | 223 | unsigned long incoming_messages; |
224 | |||
225 | struct completion exiting; | ||
226 | long thread_pid; | ||
224 | }; | 227 | }; |
225 | 228 | ||
226 | static struct notifier_block *xaction_notifier_list; | 229 | static struct notifier_block *xaction_notifier_list; |
@@ -779,6 +782,38 @@ static void set_run_to_completion(void *send_info, int i_run_to_completion) | |||
779 | spin_unlock_irqrestore(&(smi_info->si_lock), flags); | 782 | spin_unlock_irqrestore(&(smi_info->si_lock), flags); |
780 | } | 783 | } |
781 | 784 | ||
785 | static int ipmi_thread(void *data) | ||
786 | { | ||
787 | struct smi_info *smi_info = data; | ||
788 | unsigned long flags, last=1; | ||
789 | enum si_sm_result smi_result; | ||
790 | |||
791 | daemonize("kipmi%d", smi_info->intf_num); | ||
792 | allow_signal(SIGKILL); | ||
793 | set_user_nice(current, 19); | ||
794 | while (!atomic_read(&smi_info->stop_operation)) { | ||
795 | schedule_timeout(last); | ||
796 | spin_lock_irqsave(&(smi_info->si_lock), flags); | ||
797 | smi_result=smi_event_handler(smi_info, 0); | ||
798 | spin_unlock_irqrestore(&(smi_info->si_lock), flags); | ||
799 | if (smi_result == SI_SM_CALL_WITHOUT_DELAY) | ||
800 | last = 0; | ||
801 | else if (smi_result == SI_SM_CALL_WITH_DELAY) { | ||
802 | udelay(1); | ||
803 | last = 0; | ||
804 | } | ||
805 | else { | ||
806 | /* System is idle; go to sleep */ | ||
807 | last = 1; | ||
808 | current->state = TASK_INTERRUPTIBLE; | ||
809 | } | ||
810 | } | ||
811 | smi_info->thread_pid = 0; | ||
812 | complete_and_exit(&(smi_info->exiting), 0); | ||
813 | return 0; | ||
814 | } | ||
815 | |||
816 | |||
782 | static void poll(void *send_info) | 817 | static void poll(void *send_info) |
783 | { | 818 | { |
784 | struct smi_info *smi_info = send_info; | 819 | struct smi_info *smi_info = send_info; |
@@ -837,10 +872,8 @@ static void smi_timeout(unsigned long data) | |||
837 | struct timeval t; | 872 | struct timeval t; |
838 | #endif | 873 | #endif |
839 | 874 | ||
840 | if (smi_info->stop_operation) { | 875 | if (atomic_read(&smi_info->stop_operation)) |
841 | smi_info->timer_stopped = 1; | ||
842 | return; | 876 | return; |
843 | } | ||
844 | 877 | ||
845 | spin_lock_irqsave(&(smi_info->si_lock), flags); | 878 | spin_lock_irqsave(&(smi_info->si_lock), flags); |
846 | #ifdef DEBUG_TIMING | 879 | #ifdef DEBUG_TIMING |
@@ -913,7 +946,7 @@ static irqreturn_t si_irq_handler(int irq, void *data, struct pt_regs *regs) | |||
913 | smi_info->interrupts++; | 946 | smi_info->interrupts++; |
914 | spin_unlock(&smi_info->count_lock); | 947 | spin_unlock(&smi_info->count_lock); |
915 | 948 | ||
916 | if (smi_info->stop_operation) | 949 | if (atomic_read(&smi_info->stop_operation)) |
917 | goto out; | 950 | goto out; |
918 | 951 | ||
919 | #ifdef DEBUG_TIMING | 952 | #ifdef DEBUG_TIMING |
@@ -1432,7 +1465,7 @@ static u32 ipmi_acpi_gpe(void *context) | |||
1432 | smi_info->interrupts++; | 1465 | smi_info->interrupts++; |
1433 | spin_unlock(&smi_info->count_lock); | 1466 | spin_unlock(&smi_info->count_lock); |
1434 | 1467 | ||
1435 | if (smi_info->stop_operation) | 1468 | if (atomic_read(&smi_info->stop_operation)) |
1436 | goto out; | 1469 | goto out; |
1437 | 1470 | ||
1438 | #ifdef DEBUG_TIMING | 1471 | #ifdef DEBUG_TIMING |
@@ -2177,6 +2210,16 @@ static void setup_xaction_handlers(struct smi_info *smi_info) | |||
2177 | setup_dell_poweredge_bt_xaction_handler(smi_info); | 2210 | setup_dell_poweredge_bt_xaction_handler(smi_info); |
2178 | } | 2211 | } |
2179 | 2212 | ||
2213 | static inline void wait_for_timer_and_thread(struct smi_info *smi_info) | ||
2214 | { | ||
2215 | if (smi_info->thread_pid > 0) { | ||
2216 | /* wake the potentially sleeping thread */ | ||
2217 | kill_proc(smi_info->thread_pid, SIGKILL, 0); | ||
2218 | wait_for_completion(&(smi_info->exiting)); | ||
2219 | } | ||
2220 | del_timer_sync(&smi_info->si_timer); | ||
2221 | } | ||
2222 | |||
2180 | /* Returns 0 if initialized, or negative on an error. */ | 2223 | /* Returns 0 if initialized, or negative on an error. */ |
2181 | static int init_one_smi(int intf_num, struct smi_info **smi) | 2224 | static int init_one_smi(int intf_num, struct smi_info **smi) |
2182 | { | 2225 | { |
@@ -2284,8 +2327,8 @@ static int init_one_smi(int intf_num, struct smi_info **smi) | |||
2284 | new_smi->run_to_completion = 0; | 2327 | new_smi->run_to_completion = 0; |
2285 | 2328 | ||
2286 | new_smi->interrupt_disabled = 0; | 2329 | new_smi->interrupt_disabled = 0; |
2287 | new_smi->timer_stopped = 0; | 2330 | atomic_set(&new_smi->stop_operation, 0); |
2288 | new_smi->stop_operation = 0; | 2331 | new_smi->intf_num = intf_num; |
2289 | 2332 | ||
2290 | /* Start clearing the flags before we enable interrupts or the | 2333 | /* Start clearing the flags before we enable interrupts or the |
2291 | timer to avoid racing with the timer. */ | 2334 | timer to avoid racing with the timer. */ |
@@ -2303,7 +2346,14 @@ static int init_one_smi(int intf_num, struct smi_info **smi) | |||
2303 | new_smi->si_timer.function = smi_timeout; | 2346 | new_smi->si_timer.function = smi_timeout; |
2304 | new_smi->last_timeout_jiffies = jiffies; | 2347 | new_smi->last_timeout_jiffies = jiffies; |
2305 | new_smi->si_timer.expires = jiffies + SI_TIMEOUT_JIFFIES; | 2348 | new_smi->si_timer.expires = jiffies + SI_TIMEOUT_JIFFIES; |
2349 | |||
2306 | add_timer(&(new_smi->si_timer)); | 2350 | add_timer(&(new_smi->si_timer)); |
2351 | if (new_smi->si_type != SI_BT) { | ||
2352 | init_completion(&(new_smi->exiting)); | ||
2353 | new_smi->thread_pid = kernel_thread(ipmi_thread, new_smi, | ||
2354 | CLONE_FS|CLONE_FILES| | ||
2355 | CLONE_SIGHAND); | ||
2356 | } | ||
2307 | 2357 | ||
2308 | rv = ipmi_register_smi(&handlers, | 2358 | rv = ipmi_register_smi(&handlers, |
2309 | new_smi, | 2359 | new_smi, |
@@ -2345,12 +2395,8 @@ static int init_one_smi(int intf_num, struct smi_info **smi) | |||
2345 | return 0; | 2395 | return 0; |
2346 | 2396 | ||
2347 | out_err_stop_timer: | 2397 | out_err_stop_timer: |
2348 | new_smi->stop_operation = 1; | 2398 | atomic_inc(&new_smi->stop_operation); |
2349 | 2399 | wait_for_timer_and_thread(new_smi); | |
2350 | /* Wait for the timer to stop. This avoids problems with race | ||
2351 | conditions removing the timer here. */ | ||
2352 | while (!new_smi->timer_stopped) | ||
2353 | schedule_timeout_uninterruptible(1); | ||
2354 | 2400 | ||
2355 | out_err: | 2401 | out_err: |
2356 | if (new_smi->intf) | 2402 | if (new_smi->intf) |
@@ -2456,8 +2502,7 @@ static void __exit cleanup_one_si(struct smi_info *to_clean) | |||
2456 | spin_lock_irqsave(&(to_clean->si_lock), flags); | 2502 | spin_lock_irqsave(&(to_clean->si_lock), flags); |
2457 | spin_lock(&(to_clean->msg_lock)); | 2503 | spin_lock(&(to_clean->msg_lock)); |
2458 | 2504 | ||
2459 | to_clean->stop_operation = 1; | 2505 | atomic_inc(&to_clean->stop_operation); |
2460 | |||
2461 | to_clean->irq_cleanup(to_clean); | 2506 | to_clean->irq_cleanup(to_clean); |
2462 | 2507 | ||
2463 | spin_unlock(&(to_clean->msg_lock)); | 2508 | spin_unlock(&(to_clean->msg_lock)); |
@@ -2468,10 +2513,7 @@ static void __exit cleanup_one_si(struct smi_info *to_clean) | |||
2468 | interrupt. */ | 2513 | interrupt. */ |
2469 | synchronize_sched(); | 2514 | synchronize_sched(); |
2470 | 2515 | ||
2471 | /* Wait for the timer to stop. This avoids problems with race | 2516 | wait_for_timer_and_thread(to_clean); |
2472 | conditions removing the timer here. */ | ||
2473 | while (!to_clean->timer_stopped) | ||
2474 | schedule_timeout_uninterruptible(1); | ||
2475 | 2517 | ||
2476 | /* Interrupts and timeouts are stopped, now make sure the | 2518 | /* Interrupts and timeouts are stopped, now make sure the |
2477 | interface is in a clean state. */ | 2519 | interface is in a clean state. */ |