The patch titled
Subject: ipmi: simplify locking
has been added to the -mm tree. Its filename is
ipmi-simplify-locking.patch
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/SubmitChecklist when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Corey Minyard <cminyard@xxxxxxxxxx>
Subject: ipmi: simplify locking
Now that the the IPMI driver is using a tasklet, we can simplify the
locking in the driver and get rid of the message lock.
Signed-off-by: Corey Minyard <cminyard@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
drivers/char/ipmi/ipmi_si_intf.c | 54 +++++++++++------------------
1 file changed, 21 insertions(+), 33 deletions(-)
diff -puN drivers/char/ipmi/ipmi_si_intf.c~ipmi-simplify-locking drivers/char/ipmi/ipmi_si_intf.c
--- a/drivers/char/ipmi/ipmi_si_intf.c~ipmi-simplify-locking
+++ a/drivers/char/ipmi/ipmi_si_intf.c
@@ -171,7 +171,6 @@ struct smi_info {
struct si_sm_handlers *handlers;
enum si_type si_type;
spinlock_t si_lock;
- spinlock_t msg_lock;
struct list_head xmit_msgs;
struct list_head hp_xmit_msgs;
struct ipmi_smi_msg *curr_msg;
@@ -350,13 +349,6 @@ static enum si_sm_result start_next_msg(
struct timeval t;
#endif
- /*
- * No need to save flags, we aleady have interrupts off and we
- * already hold the SMI lock.
- */
- if (!smi_info->run_to_completion)
- spin_lock(&(smi_info->msg_lock));
-
/* Pick the high priority queue first. */
if (!list_empty(&(smi_info->hp_xmit_msgs))) {
entry = smi_info->hp_xmit_msgs.next;
@@ -394,9 +386,6 @@ static enum si_sm_result start_next_msg(
rv = SI_SM_CALL_WITHOUT_DELAY;
}
out:
- if (!smi_info->run_to_completion)
- spin_unlock(&(smi_info->msg_lock));
-
return rv;
}
@@ -879,19 +868,6 @@ static void sender(void *
printk("**Enqueue: %d.%9.9d\n", t.tv_sec, t.tv_usec);
#endif
- /*
- * last_timeout_jiffies is updated here to avoid
- * smi_timeout() handler passing very large time_diff
- * value to smi_event_handler() that causes
- * the send command to abort.
- */
- smi_info->last_timeout_jiffies = jiffies;
-
- mod_timer(&smi_info->si_timer, jiffies + SI_TIMEOUT_JIFFIES);
-
- if (smi_info->thread)
- wake_up_process(smi_info->thread);
-
if (smi_info->run_to_completion) {
/*
* If we are running to completion, then throw it in
@@ -914,15 +890,26 @@ static void sender(void *
return;
}
- spin_lock_irqsave(&smi_info->msg_lock, flags);
+ spin_lock_irqsave(&smi_info->si_lock, flags);
if (priority > 0)
list_add_tail(&msg->link, &smi_info->hp_xmit_msgs);
else
list_add_tail(&msg->link, &smi_info->xmit_msgs);
- spin_unlock_irqrestore(&smi_info->msg_lock, flags);
- spin_lock_irqsave(&smi_info->si_lock, flags);
if (smi_info->si_state == SI_NORMAL && smi_info->curr_msg == NULL) {
+ /*
+ * last_timeout_jiffies is updated here to avoid
+ * smi_timeout() handler passing very large time_diff
+ * value to smi_event_handler() that causes
+ * the send command to abort.
+ */
+ smi_info->last_timeout_jiffies = jiffies;
+
+ mod_timer(&smi_info->si_timer, jiffies + SI_TIMEOUT_JIFFIES);
+
+ if (smi_info->thread)
+ wake_up_process(smi_info->thread);
+
start_next_msg(smi_info);
smi_event_handler(smi_info, 0);
}
@@ -1026,16 +1013,19 @@ static int ipmi_thread(void *data)
static void poll(void *send_info)
{
struct smi_info *smi_info = send_info;
- unsigned long flags;
+ unsigned long flags = 0;
+ int run_to_completion = smi_info->run_to_completion;
/*
* Make sure there is some delay in the poll loop so we can
* drive time forward and timeout things.
*/
udelay(10);
- spin_lock_irqsave(&smi_info->si_lock, flags);
+ if (!run_to_completion)
+ spin_lock_irqsave(&smi_info->si_lock, flags);
smi_event_handler(smi_info, 10);
- spin_unlock_irqrestore(&smi_info->si_lock, flags);
+ if (!run_to_completion)
+ spin_unlock_irqrestore(&smi_info->si_lock, flags);
}
static void request_events(void *send_info)
@@ -1672,10 +1662,8 @@ static struct smi_info *smi_info_alloc(v
{
struct smi_info *info = kzalloc(sizeof(*info), GFP_KERNEL);
- if (info) {
+ if (info)
spin_lock_init(&info->si_lock);
- spin_lock_init(&info->msg_lock);
- }
return info;
}
_
Subject: Subject: ipmi: simplify locking
Patches currently in -mm which might be from cminyard@xxxxxxxxxx are
ipmi-decreases-the-ipmi-message-transaction-time-in-interrupt-mode.patch
ipmi-increase-kcs-timeouts.patch
ipmi-use-a-tasklet-for-handling-received-messages.patch
ipmi-fix-message-handling-during-panics.patch
ipmi-simplify-locking.patch
ipmi-use-locks-on-watchdog-timeout-set-on-reboot.patch
--
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
