drivers/dca: convert dca_lock to a raw spinlock

PATCH New Mike Galbraith 2 participants 5 messages Jul 7, 2010 – Jul 29, 2010

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Mike Galbraith

author

2010-07-07 08:29 UTC #0 lore raw

PATCH 1/1 drivers/dca: convert dca_lock to a raw spinlock

drivers/dca: convert dca_lock to a raw spinlock

[   25.607517] igb 0000:01:00.0: DCA enabled
[   25.607524] BUG: sleeping function called from invalid context at kernel/rtmutex.c:684
[   25.607528] pcnt: 1 0 in_atomic(): 1, irqs_disabled(): 0, pid: 1805, name: modprobe
[   25.607532] Pid: 1805, comm: modprobe Tainted: G   M    W N  2.6.33.5-rt23-rt_debug #2
[   25.607536] Call Trace:
[   25.607557]  [<ffffffff820078a1>] try_stack_unwind+0x151/0x1a0
[   25.607566]  [<ffffffff820062c2>] dump_trace+0x92/0x370
[   25.607573]  [<ffffffff8200731c>] show_trace_log_lvl+0x5c/0x80
[   25.607578]  [<ffffffff82007355>] show_trace+0x15/0x20
[   25.607587]  [<ffffffff823f4588>] dump_stack+0x77/0x8f
[   25.607595]  [<ffffffff82043f2a>] __might_sleep+0x11a/0x130
[   25.607602]  [<ffffffff823f7b93>] rt_spin_lock+0x83/0x90
[   25.607611]  [<ffffffffa0209138>] dca_common_get_tag+0x28/0x80 [dca]
[   25.607622]  [<ffffffffa02091c8>] dca3_get_tag+0x18/0x20 [dca]
[   25.607634]  [<ffffffffa0244e71>] igb_update_dca+0xb1/0x1d0 [igb]
[   25.607649]  [<ffffffffa0244ff5>] igb_setup_dca+0x65/0x80 [igb]
[   25.607663]  [<ffffffffa02535a6>] igb_probe+0x946/0xe4d [igb]
[   25.607678]  [<ffffffff82247517>] local_pci_probe+0x17/0x20
[   25.607686]  [<ffffffff82248661>] pci_device_probe+0x121/0x130
[   25.607699]  [<ffffffff822e4832>] driver_probe_device+0xd2/0x2e0
[   25.607707]  [<ffffffff822e4adb>] __driver_attach+0x9b/0xa0
[   25.607714]  [<ffffffff822e3d1b>] bus_for_each_dev+0x6b/0xa0
[   25.607720]  [<ffffffff822e4591>] driver_attach+0x21/0x30
[   25.607727]  [<ffffffff822e3425>] bus_add_driver+0x1e5/0x350
[   25.607734]  [<ffffffff822e4e41>] driver_register+0x81/0x160
[   25.607742]  [<ffffffff8224890f>] __pci_register_driver+0x6f/0xf0
[   25.607752]  [<ffffffffa011505b>] igb_init_module+0x5b/0x5d [igb]
[   25.607769]  [<ffffffff820001dd>] do_one_initcall+0x3d/0x1a0
[   25.607778]  [<ffffffff820961f6>] sys_init_module+0xe6/0x270
[   25.607786]  [<ffffffff82003232>] system_call_fastpath+0x16/0x1b
[   25.607794]  [<00007f84d6783f4a>] 0x7f84d6783f4a

Signed-off-by Mike Galbraith <[email protected]>

LKML-Reference: <new-submission>

---
 drivers/dca/dca-core.c |   36 ++++++++++++++++++------------------
 1 file changed, 18 insertions(+), 18 deletions(-)

drivers/dca/dca-core.c +18 ~~-18~~

Index: linux-2.6.33-rt/drivers/dca/dca-core.c
===================================================================
@@ -34,7 +34,7 @@ MODULE_VERSION(DCA_VERSION);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Intel Corporation");
 
-static DEFINE_SPINLOCK(dca_lock);
+static DEFINE_RAW_SPINLOCK(dca_lock);
 
 static LIST_HEAD(dca_domains);

@@ -139,19 +139,19 @@ int dca_add_requester(struct device *dev
 	if (!dev)
 		return -EFAULT;
 
-	spin_lock_irqsave(&dca_lock, flags);
+	raw_spin_lock_irqsave(&dca_lock, flags);
 
 	/* check if the requester has not been added already */
 	dca = dca_find_provider_by_dev(dev);
 	if (dca) {
-		spin_unlock_irqrestore(&dca_lock, flags);
+		raw_spin_unlock_irqrestore(&dca_lock, flags);
 		return -EEXIST;
 	}
 
 	pci_rc = dca_pci_rc_from_dev(dev);
 	domain = dca_find_domain(pci_rc);
 	if (!domain) {
-		spin_unlock_irqrestore(&dca_lock, flags);
+		raw_spin_unlock_irqrestore(&dca_lock, flags);
 		return -ENODEV;
 	}

@@ -161,17 +161,17 @@ int dca_add_requester(struct device *dev
 			break;
 	}
 
-	spin_unlock_irqrestore(&dca_lock, flags);
+	raw_spin_unlock_irqrestore(&dca_lock, flags);
 
 	if (slot < 0)
 		return slot;
 
 	err = dca_sysfs_add_req(dca, dev, slot);
 	if (err) {
-		spin_lock_irqsave(&dca_lock, flags);
+		raw_spin_lock_irqsave(&dca_lock, flags);
 		if (dca == dca_find_provider_by_dev(dev))
 			dca->ops->remove_requester(dca, dev);
-		spin_unlock_irqrestore(&dca_lock, flags);
+		raw_spin_unlock_irqrestore(&dca_lock, flags);
 		return err;
 	}

@@ -192,14 +192,14 @@ int dca_remove_requester(struct device *
 	if (!dev)
 		return -EFAULT;
 
-	spin_lock_irqsave(&dca_lock, flags);
+	raw_spin_lock_irqsave(&dca_lock, flags);
 	dca = dca_find_provider_by_dev(dev);
 	if (!dca) {
-		spin_unlock_irqrestore(&dca_lock, flags);
+		raw_spin_unlock_irqrestore(&dca_lock, flags);
 		return -ENODEV;
 	}
 	slot = dca->ops->remove_requester(dca, dev);
-	spin_unlock_irqrestore(&dca_lock, flags);
+	raw_spin_unlock_irqrestore(&dca_lock, flags);
 
 	if (slot < 0)
 		return slot;

@@ -221,16 +221,16 @@ u8 dca_common_get_tag(struct device *dev
 	u8 tag;
 	unsigned long flags;
 
-	spin_lock_irqsave(&dca_lock, flags);
+	raw_spin_lock_irqsave(&dca_lock, flags);
 
 	dca = dca_find_provider_by_dev(dev);
 	if (!dca) {
-		spin_unlock_irqrestore(&dca_lock, flags);
+		raw_spin_unlock_irqrestore(&dca_lock, flags);
 		return -ENODEV;
 	}
 	tag = dca->ops->get_tag(dca, dev, cpu);
 
-	spin_unlock_irqrestore(&dca_lock, flags);
+	raw_spin_unlock_irqrestore(&dca_lock, flags);
 	return tag;
 }

@@ -309,14 +309,14 @@ int register_dca_provider(struct dca_pro
 	if (err)
 		return err;
 
-	spin_lock_irqsave(&dca_lock, flags);
+	raw_spin_lock_irqsave(&dca_lock, flags);
 	domain = dca_get_domain(dev);
 	if (!domain) {
-		spin_unlock_irqrestore(&dca_lock, flags);
+		raw_spin_unlock_irqrestore(&dca_lock, flags);
 		return -ENODEV;
 	}
 	list_add(&dca->node, &domain->dca_providers);
-	spin_unlock_irqrestore(&dca_lock, flags);
+	raw_spin_unlock_irqrestore(&dca_lock, flags);
 
 	blocking_notifier_call_chain(&dca_provider_chain,
 				     DCA_PROVIDER_ADD, NULL);

@@ -337,7 +337,7 @@ void unregister_dca_provider(struct dca_
 	blocking_notifier_call_chain(&dca_provider_chain,
 				     DCA_PROVIDER_REMOVE, NULL);
 
-	spin_lock_irqsave(&dca_lock, flags);
+	raw_spin_lock_irqsave(&dca_lock, flags);
 
 	list_del(&dca->node);

@@ -346,7 +346,7 @@ void unregister_dca_provider(struct dca_
 	if (list_empty(&domain->dca_providers))
 		dca_free_domain(domain);
 
-	spin_unlock_irqrestore(&dca_lock, flags);
+	raw_spin_unlock_irqrestore(&dca_lock, flags);
 
 	dca_sysfs_remove_provider(dca);
 }

Mike Galbraith

author

2010-07-23 10:17 UTC #1 lore raw

PATCH 1/1 drivers/dca: convert dca_lock to a raw spinlock V2

Thanks for the hint+ Thomas. V2 moves allocation outside the lock.

drivers/dca: convert dca_lock to a raw spinlock

[   25.607517] igb 0000:01:00.0: DCA enabled
[   25.607524] BUG: sleeping function called from invalid context at kernel/rtmutex.c:684
[   25.607528] pcnt: 1 0 in_atomic(): 1, irqs_disabled(): 0, pid: 1805, name: modprobe
[   25.607532] Pid: 1805, comm: modprobe Tainted: G   M    W N  2.6.33.5-rt23-rt_debug #2
[   25.607536] Call Trace:
[   25.607557]  [<ffffffff820078a1>] try_stack_unwind+0x151/0x1a0
[   25.607566]  [<ffffffff820062c2>] dump_trace+0x92/0x370
[   25.607573]  [<ffffffff8200731c>] show_trace_log_lvl+0x5c/0x80
[   25.607578]  [<ffffffff82007355>] show_trace+0x15/0x20
[   25.607587]  [<ffffffff823f4588>] dump_stack+0x77/0x8f
[   25.607595]  [<ffffffff82043f2a>] __might_sleep+0x11a/0x130
[   25.607602]  [<ffffffff823f7b93>] rt_spin_lock+0x83/0x90
[   25.607611]  [<ffffffffa0209138>] dca_common_get_tag+0x28/0x80 [dca]
[   25.607622]  [<ffffffffa02091c8>] dca3_get_tag+0x18/0x20 [dca]
[   25.607634]  [<ffffffffa0244e71>] igb_update_dca+0xb1/0x1d0 [igb]
[   25.607649]  [<ffffffffa0244ff5>] igb_setup_dca+0x65/0x80 [igb]
[   25.607663]  [<ffffffffa02535a6>] igb_probe+0x946/0xe4d [igb]
[   25.607678]  [<ffffffff82247517>] local_pci_probe+0x17/0x20
[   25.607686]  [<ffffffff82248661>] pci_device_probe+0x121/0x130
[   25.607699]  [<ffffffff822e4832>] driver_probe_device+0xd2/0x2e0
[   25.607707]  [<ffffffff822e4adb>] __driver_attach+0x9b/0xa0
[   25.607714]  [<ffffffff822e3d1b>] bus_for_each_dev+0x6b/0xa0
[   25.607720]  [<ffffffff822e4591>] driver_attach+0x21/0x30
[   25.607727]  [<ffffffff822e3425>] bus_add_driver+0x1e5/0x350
[   25.607734]  [<ffffffff822e4e41>] driver_register+0x81/0x160
[   25.607742]  [<ffffffff8224890f>] __pci_register_driver+0x6f/0xf0
[   25.607752]  [<ffffffffa011505b>] igb_init_module+0x5b/0x5d [igb]
[   25.607769]  [<ffffffff820001dd>] do_one_initcall+0x3d/0x1a0
[   25.607778]  [<ffffffff820961f6>] sys_init_module+0xe6/0x270
[   25.607786]  [<ffffffff82003232>] system_call_fastpath+0x16/0x1b
[   25.607794]  [<00007f84d6783f4a>] 0x7f84d6783f4a

Signed-off-by Mike Galbraith <[email protected]>

LKML-Reference: <new-submission>

---
 drivers/dca/dca-core.c |   62 +++++++++++++++++++++++++++----------------------
 1 file changed, 35 insertions(+), 27 deletions(-)

drivers/dca/dca-core.c +35 ~~-27~~

Index: linux-2.6/drivers/dca/dca-core.c
===================================================================
@@ -35,7 +35,7 @@ MODULE_VERSION(DCA_VERSION);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Intel Corporation");
 
-static DEFINE_SPINLOCK(dca_lock);
+static DEFINE_RAW_SPINLOCK(dca_lock);
 
 static LIST_HEAD(dca_domains);

@@ -88,13 +88,6 @@ static struct dca_domain *dca_get_domain
 
 	rc = dca_pci_rc_from_dev(dev);
 	domain = dca_find_domain(rc);
-
-	if (!domain) {
-		domain = dca_allocate_domain(rc);
-		if (domain)
-			list_add(&domain->node, &dca_domains);
-	}
-
 	return domain;
 }

@@ -140,19 +133,19 @@ int dca_add_requester(struct device *dev
 	if (!dev)
 		return -EFAULT;
 
-	spin_lock_irqsave(&dca_lock, flags);
+	raw_spin_lock_irqsave(&dca_lock, flags);
 
 	/* check if the requester has not been added already */
 	dca = dca_find_provider_by_dev(dev);
 	if (dca) {
-		spin_unlock_irqrestore(&dca_lock, flags);
+		raw_spin_unlock_irqrestore(&dca_lock, flags);
 		return -EEXIST;
 	}
 
 	pci_rc = dca_pci_rc_from_dev(dev);
 	domain = dca_find_domain(pci_rc);
 	if (!domain) {
-		spin_unlock_irqrestore(&dca_lock, flags);
+		raw_spin_unlock_irqrestore(&dca_lock, flags);
 		return -ENODEV;
 	}

@@ -162,17 +155,17 @@ int dca_add_requester(struct device *dev
 			break;
 	}
 
-	spin_unlock_irqrestore(&dca_lock, flags);
+	raw_spin_unlock_irqrestore(&dca_lock, flags);
 
 	if (slot < 0)
 		return slot;
 
 	err = dca_sysfs_add_req(dca, dev, slot);
 	if (err) {
-		spin_lock_irqsave(&dca_lock, flags);
+		raw_spin_lock_irqsave(&dca_lock, flags);
 		if (dca == dca_find_provider_by_dev(dev))
 			dca->ops->remove_requester(dca, dev);
-		spin_unlock_irqrestore(&dca_lock, flags);
+		raw_spin_unlock_irqrestore(&dca_lock, flags);
 		return err;
 	}

@@ -193,14 +186,14 @@ int dca_remove_requester(struct device *
 	if (!dev)
 		return -EFAULT;
 
-	spin_lock_irqsave(&dca_lock, flags);
+	raw_spin_lock_irqsave(&dca_lock, flags);
 	dca = dca_find_provider_by_dev(dev);
 	if (!dca) {
-		spin_unlock_irqrestore(&dca_lock, flags);
+		raw_spin_unlock_irqrestore(&dca_lock, flags);
 		return -ENODEV;
 	}
 	slot = dca->ops->remove_requester(dca, dev);
-	spin_unlock_irqrestore(&dca_lock, flags);
+	raw_spin_unlock_irqrestore(&dca_lock, flags);
 
 	if (slot < 0)
 		return slot;

@@ -222,16 +215,16 @@ u8 dca_common_get_tag(struct device *dev
 	u8 tag;
 	unsigned long flags;
 
-	spin_lock_irqsave(&dca_lock, flags);
+	raw_spin_lock_irqsave(&dca_lock, flags);
 
 	dca = dca_find_provider_by_dev(dev);
 	if (!dca) {
-		spin_unlock_irqrestore(&dca_lock, flags);
+		raw_spin_unlock_irqrestore(&dca_lock, flags);
 		return -ENODEV;
 	}
 	tag = dca->ops->get_tag(dca, dev, cpu);
 
-	spin_unlock_irqrestore(&dca_lock, flags);
+	raw_spin_unlock_irqrestore(&dca_lock, flags);
 	return tag;
 }

@@ -304,23 +297,38 @@ int register_dca_provider(struct dca_pro
 {
 	int err;
 	unsigned long flags;
-	struct dca_domain *domain;
+	struct dca_domain *domain, *newdomain = NULL;
+        struct pci_bus *rc;
 
 	err = dca_sysfs_add_provider(dca, dev);
 	if (err)
 		return err;
 
-	spin_lock_irqsave(&dca_lock, flags);
+	raw_spin_lock_irqsave(&dca_lock, flags);
+	rc = dca_pci_rc_from_dev(dev);
 	domain = dca_get_domain(dev);
 	if (!domain) {
-		spin_unlock_irqrestore(&dca_lock, flags);
-		return -ENODEV;
+		raw_spin_unlock_irqrestore(&dca_lock, flags);
+
+		newdomain = dca_allocate_domain(rc);
+		if (!newdomain)
+			return -ENODEV;
+
+		raw_spin_lock_irqsave(&dca_lock, flags);
+		/* Recheck, we might have raced after dropping the lock */
+		domain = dca_get_domain(dev);
+		if (!domain) {
+			domain = newdomain;
+			newdomain = NULL;
+			list_add(&domain->node, &dca_domains);
+		}
 	}
 	list_add(&dca->node, &domain->dca_providers);
-	spin_unlock_irqrestore(&dca_lock, flags);
+	raw_spin_unlock_irqrestore(&dca_lock, flags);
 
 	blocking_notifier_call_chain(&dca_provider_chain,
 				     DCA_PROVIDER_ADD, NULL);
+	kfree(newdomain);
 	return 0;
 }
 EXPORT_SYMBOL_GPL(register_dca_provider);

@@ -338,7 +346,7 @@ void unregister_dca_provider(struct dca_
 	blocking_notifier_call_chain(&dca_provider_chain,
 				     DCA_PROVIDER_REMOVE, NULL);
 
-	spin_lock_irqsave(&dca_lock, flags);
+	raw_spin_lock_irqsave(&dca_lock, flags);
 
 	list_del(&dca->node);

@@ -347,7 +355,7 @@ void unregister_dca_provider(struct dca_
 	if (list_empty(&domain->dca_providers))
 		dca_free_domain(domain);
 
-	spin_unlock_irqrestore(&dca_lock, flags);
+	raw_spin_unlock_irqrestore(&dca_lock, flags);
 
 	dca_sysfs_remove_provider(dca);
 }

John Kacur

2010-07-28 21:29 UTC #2 lore raw

Re: [patch] drivers/dca: convert dca_lock to a raw spinlock V2

Quoted 208 lines · Mike Galbraith

Thanks for the hint+ Thomas. V2 moves allocation outside the lock.

drivers/dca: convert dca_lock to a raw spinlock

[ 25.607517] igb 0000:01:00.0: DCA enabled
[ 25.607524] BUG: sleeping function called from invalid context at kernel/rtmutex.c:684 [ 25.607528] pcnt: 1 0 in_atomic(): 1, irqs_disabled(): 0, pid: 1805, name: modprobe [ 25.607532] Pid: 1805, comm: modprobe Tainted: G M W N 2.6.33.5-rt23-rt_debug #2 [ 25.607536] Call Trace:
[ 25.607557] [<ffffffff820078a1>] try_stack_unwind+0x151/0x1a0
[ 25.607566] [<ffffffff820062c2>] dump_trace+0x92/0x370
[ 25.607573] [<ffffffff8200731c>] show_trace_log_lvl+0x5c/0x80
[ 25.607578] [<ffffffff82007355>] show_trace+0x15/0x20
[ 25.607587] [<ffffffff823f4588>] dump_stack+0x77/0x8f
[ 25.607595] [<ffffffff82043f2a>] __might_sleep+0x11a/0x130
[ 25.607602] [<ffffffff823f7b93>] rt_spin_lock+0x83/0x90
[ 25.607611] [<ffffffffa0209138>] dca_common_get_tag+0x28/0x80 [dca]
[ 25.607622] [<ffffffffa02091c8>] dca3_get_tag+0x18/0x20 [dca]
[ 25.607634] [<ffffffffa0244e71>] igb_update_dca+0xb1/0x1d0 [igb]
[ 25.607649] [<ffffffffa0244ff5>] igb_setup_dca+0x65/0x80 [igb]
[ 25.607663] [<ffffffffa02535a6>] igb_probe+0x946/0xe4d [igb]
[ 25.607678] [<ffffffff82247517>] local_pci_probe+0x17/0x20
[ 25.607686] [<ffffffff82248661>] pci_device_probe+0x121/0x130
[ 25.607699] [<ffffffff822e4832>] driver_probe_device+0xd2/0x2e0
[ 25.607707] [<ffffffff822e4adb>] __driver_attach+0x9b/0xa0
[ 25.607714] [<ffffffff822e3d1b>] bus_for_each_dev+0x6b/0xa0
[ 25.607720] [<ffffffff822e4591>] driver_attach+0x21/0x30
[ 25.607727] [<ffffffff822e3425>] bus_add_driver+0x1e5/0x350
[ 25.607734] [<ffffffff822e4e41>] driver_register+0x81/0x160
[ 25.607742] [<ffffffff8224890f>] __pci_register_driver+0x6f/0xf0
[ 25.607752] [<ffffffffa011505b>] igb_init_module+0x5b/0x5d [igb]
[ 25.607769] [<ffffffff820001dd>] do_one_initcall+0x3d/0x1a0
[ 25.607778] [<ffffffff820961f6>] sys_init_module+0xe6/0x270
[ 25.607786] [<ffffffff82003232>] system_call_fastpath+0x16/0x1b
[ 25.607794] [<00007f84d6783f4a>] 0x7f84d6783f4a

Signed-off-by Mike Galbraith <[email protected]>

LKML-Reference: <new-submission>

---
drivers/dca/dca-core.c | 62 +++++++++++++++++++++++++++----------------------

 1 file changed, 35 insertions(+), 27 deletions(-)

Index: linux-2.6/drivers/dca/dca-core.c
===================================================================

drivers/dca/dca-core.c +34 ~~-26~~

@@ -35,7 +35,7 @@ MODULE_VERSION(DCA_VERSION);
  MODULE_LICENSE("GPL");
  MODULE_AUTHOR("Intel Corporation");
 
-static DEFINE_SPINLOCK(dca_lock);
+static DEFINE_RAW_SPINLOCK(dca_lock);
 
  static LIST_HEAD(dca_domains);

@@ -88,13 +88,6 @@ static struct dca_domain *dca_get_domain
 
        rc = dca_pci_rc_from_dev(dev);
        domain = dca_find_domain(rc);
-
-       if (!domain) {
-               domain = dca_allocate_domain(rc);
-               if (domain)
-                       list_add(&domain->node, &dca_domains);
-       }
-
        return domain;
  }

@@ -140,19 +133,19 @@ int dca_add_requester(struct device *dev
        if (!dev)
                return -EFAULT;
 
-       spin_lock_irqsave(&dca_lock, flags);
+       raw_spin_lock_irqsave(&dca_lock, flags);
 
        /* check if the requester has not been added already */
        dca = dca_find_provider_by_dev(dev);
        if (dca) {
-               spin_unlock_irqrestore(&dca_lock, flags);
+               raw_spin_unlock_irqrestore(&dca_lock, flags);
                return -EEXIST;
        }
 
        pci_rc = dca_pci_rc_from_dev(dev);
        domain = dca_find_domain(pci_rc);
        if (!domain) {
-               spin_unlock_irqrestore(&dca_lock, flags);
+               raw_spin_unlock_irqrestore(&dca_lock, flags);
                return -ENODEV;
        }

@@ -162,17 +155,17 @@ int dca_add_requester(struct device *dev
                        break;
        }
 
-       spin_unlock_irqrestore(&dca_lock, flags);
+       raw_spin_unlock_irqrestore(&dca_lock, flags);
 
        if (slot < 0)
                return slot;
 
        err = dca_sysfs_add_req(dca, dev, slot);
        if (err) {
-               spin_lock_irqsave(&dca_lock, flags);
+               raw_spin_lock_irqsave(&dca_lock, flags);
                if (dca == dca_find_provider_by_dev(dev))
                        dca->ops->remove_requester(dca, dev);
-               spin_unlock_irqrestore(&dca_lock, flags);
+               raw_spin_unlock_irqrestore(&dca_lock, flags);
                return err;
        }

@@ -193,14 +186,14 @@ int dca_remove_requester(struct device *
        if (!dev)
                return -EFAULT;
 
-       spin_lock_irqsave(&dca_lock, flags);
+       raw_spin_lock_irqsave(&dca_lock, flags);
        dca = dca_find_provider_by_dev(dev);
        if (!dca) {
-               spin_unlock_irqrestore(&dca_lock, flags);
+               raw_spin_unlock_irqrestore(&dca_lock, flags);
                return -ENODEV;
        }
        slot = dca->ops->remove_requester(dca, dev);
-       spin_unlock_irqrestore(&dca_lock, flags);
+       raw_spin_unlock_irqrestore(&dca_lock, flags);
 
        if (slot < 0)
                return slot;

@@ -222,16 +215,16 @@ u8 dca_common_get_tag(struct device *dev
        u8 tag;
        unsigned long flags;
 
-       spin_lock_irqsave(&dca_lock, flags);
+       raw_spin_lock_irqsave(&dca_lock, flags);
 
        dca = dca_find_provider_by_dev(dev);
        if (!dca) {
-               spin_unlock_irqrestore(&dca_lock, flags);
+               raw_spin_unlock_irqrestore(&dca_lock, flags);
                return -ENODEV;
        }
        tag = dca->ops->get_tag(dca, dev, cpu);
 
-       spin_unlock_irqrestore(&dca_lock, flags);
+       raw_spin_unlock_irqrestore(&dca_lock, flags);
        return tag;
  }

@@ -304,23 +297,38 @@ int register_dca_provider(struct dca_pro
  {
        int err;
        unsigned long flags;
-       struct dca_domain *domain;
+       struct dca_domain *domain, *newdomain = NULL;
+        struct pci_bus *rc;
 
        err = dca_sysfs_add_provider(dca, dev);
        if (err)
                return err;
 
-       spin_lock_irqsave(&dca_lock, flags);
+       raw_spin_lock_irqsave(&dca_lock, flags);
+       rc = dca_pci_rc_from_dev(dev);
        domain = dca_get_domain(dev);
        if (!domain) {
-               spin_unlock_irqrestore(&dca_lock, flags);
-               return -ENODEV;
+               raw_spin_unlock_irqrestore(&dca_lock, flags);
+
+               newdomain = dca_allocate_domain(rc);
+               if (!newdomain)
+                       return -ENODEV;
+
+               raw_spin_lock_irqsave(&dca_lock, flags);
+               /* Recheck, we might have raced after dropping the lock */
+               domain = dca_get_domain(dev);
+               if (!domain) {
+                       domain = newdomain;
+                       newdomain = NULL;
+                       list_add(&domain->node, &dca_domains);
+               }
        }
        list_add(&dca->node, &domain->dca_providers);
-       spin_unlock_irqrestore(&dca_lock, flags);
+       raw_spin_unlock_irqrestore(&dca_lock, flags);
 
        blocking_notifier_call_chain(&dca_provider_chain,
                                     DCA_PROVIDER_ADD, NULL);
+       kfree(newdomain);
        return 0;
  }
  EXPORT_SYMBOL_GPL(register_dca_provider);

@@ -338,7 +346,7 @@ void unregister_dca_provider(struct dca_
        blocking_notifier_call_chain(&dca_provider_chain,
                                     DCA_PROVIDER_REMOVE, NULL);
 
-       spin_lock_irqsave(&dca_lock, flags);
+       raw_spin_lock_irqsave(&dca_lock, flags);
 
        list_del(&dca->node);

drivers/dca/dca-core.c void unregister_dca_provider(struct dca_ · line 361

Quoted 8 lines

drivers/dca/dca-core.c +1 -1

@@ -347,7 +355,7 @@ void unregister_dca_provider(struct dca_
        if (list_empty(&domain->dca_providers))
                dca_free_domain(domain);
 
-       spin_unlock_irqrestore(&dca_lock, flags);
+       raw_spin_unlock_irqrestore(&dca_lock, flags);
 
        dca_sysfs_remove_provider(dca);
  }

Hi Mike

Please have a look at tip/rt/2.6.33
Afaict, Thomas already applied your V1 of the patch, plus his fix for the compile problem.

Since the above looks slightly cleaner, maybe you just need to spin a clean-up patch
of what is in tip/rt/2.6.33

Thanks
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Mike Galbraith

author

2010-07-29 04:24 UTC #3 lore raw

Re: [patch] drivers/dca: convert dca_lock to a raw spinlock V2

Quoted 3 lines · John Kacur

Since the above looks slightly cleaner, maybe you just need to spin a clean-up patch
of what is in tip/rt/2.6.33

Ok, dinky delta below.

drivers/dca: minor cleanup of dca-core.c

Signed-off-by Mike Galbraith <[email protected]>

drivers/dca/dca-core.c +3 -1

@@ -297,17 +297,19 @@ int register_dca_provider(struct dca_pro
 	int err;
 	unsigned long flags;
 	struct dca_domain *domain, *newdomain = NULL;
+        struct pci_bus *rc;
 
 	err = dca_sysfs_add_provider(dca, dev);
 	if (err)
 		return err;
 
 	raw_spin_lock_irqsave(&dca_lock, flags);
+	rc = dca_pci_rc_from_dev(dev);
 	domain = dca_get_domain(dev);
 	if (!domain) {
 		raw_spin_unlock_irqrestore(&dca_lock, flags);
 
-		newdomain = dca_allocate_domain(dca_pci_rc_from_dev(dev));
+		newdomain = dca_allocate_domain(rc);
 		if (!newdomain)
 			return -ENODEV;

John Kacur

Acked-by

2010-07-29 18:45 UTC #4 lore raw

Re: [patch] drivers/dca: convert dca_lock to a raw spinlock V2

Quoted 28 lines · Mike Galbraith

Quoted 3 lines · John Kacur
Since the above looks slightly cleaner, maybe you just need to spin a clean-up patch
of what is in tip/rt/2.6.33
Ok, dinky delta below.
drivers/dca: minor cleanup of dca-core.c
Signed-off-by Mike Galbraith <[email protected]>
drivers/dca/dca-core.c +2 -0
@@ -297,17 +297,19 @@ int register_dca_provider(struct dca_pro
 	int err;
 	unsigned long flags;
 	struct dca_domain *domain, *newdomain = NULL;
+        struct pci_bus *rc;
 
 	err = dca_sysfs_add_provider(dca, dev);
 	if (err)
 		return err;
 
 	raw_spin_lock_irqsave(&dca_lock, flags);
+	rc = dca_pci_rc_from_dev(dev);
 	domain = dca_get_domain(dev);
 	if (!domain) {

drivers/dca/dca-core.c int register_dca_provider(struct dca_pro

Quoted 10 lines

drivers/dca/dca-core.c +1 -2

 		raw_spin_unlock_irqrestore(&dca_lock, flags);
 
-		newdomain = dca_allocate_domain(dca_pci_rc_from_dev(dev));
+		newdomain = dca_allocate_domain(rc);
 		if (!newdomain)
 			return -ENODEV;
 
 
 
--

Thanks Mike, I've applied this to my own tree for testing.

Acked-by John Kacur <[email protected]>