[PATCH -v4 0/4] PCI : bridge resource reallocation patchset -- followup

[PATCH -v4 0/4] PCI : bridge resource reallocation patchset -- followup

[Yinghai Lu]

e084882: PCI: only enable pci realloc when SRIOV bar is not assigned
22f7543: PCI: print out suggestion about using pci=realloc
c81bbda: PCI: Make pci bridge reallocating enabled/disabled
b1b520d: PCI: Retry on type IORESOURCE_IO allocation.

are left over after Jesse pickup more of them.
it will try to auto detect if need to use pci=realloc, and print out suggestion.

could get from

	git://git.kernel.org/pub/scm/linux/kernel/git/yinghai/linux-yinghai.git for-pci-next


-v3: Resend according to Jesse. Update ack and etc.
     last one add CONFIG_PCI_REALLOC_ENABLE_DETECT according to Jesse.
-v4: left over that need refreshing against pci/linux-next...
    resending accoring to Jesse.

Thanks

Yinghai

 Documentation/kernel-parameters.txt |    9 +++-
 drivers/pci/Kconfig                 |   10 +++++
 drivers/pci/pci.c                   |    4 +-
 drivers/pci/pci.h                   |    2 +-
 drivers/pci/setup-bus.c             |   75 +++++++++++++++++++++++++++--------
 5 files changed, 79 insertions(+), 21 deletions(-)

[PATCH 1/4] PCI: Retry on type IORESOURCE_IO allocation.

[Yinghai Lu]

During reenabling pci reallocating for pci bridge by clean the small size in
bridge and assign with requested + optional size for first several try,
Ram mention could have problem with one case
	https://bugzilla.kernel.org/show_bug.cgi?id=15960

After checking the booting log in
	https://lkml.org/lkml/2010/4/19/44
	[regression, bisected] Xonar DX invalid PCI I/O range since 977d17bb174

We should not stop too early for io ports.
	Apr 19 10:19:38 [kernel] pci 0000:04:00.0: BAR 7: can't assign io (size 0x4000)
	Apr 19 10:19:38 [kernel] pci 0000:05:01.0: BAR 8: assigned [mem 0x80400000-0x805fffff]
	Apr 19 10:19:38 [kernel] pci 0000:05:01.0: BAR 7: can't assign io (size 0x2000)
	Apr 19 10:19:38 [kernel] pci 0000:05:02.0: BAR 7: can't assign io (size 0x1000)
	Apr 19 10:19:38 [kernel] pci 0000:05:03.0: BAR 7: can't assign io (size 0x1000)
	Apr 19 10:19:38 [kernel] pci 0000:08:00.0: BAR 7: can't assign io (size 0x1000)
	Apr 19 10:19:38 [kernel] pci 0000:09:04.0: BAR 0: can't assign io (size 0x100)
and clear 00:1c.0 to retry again.

The patch remove the IORESOUCE_IO checking, and try one more time.
and we will have chance to get allocation for 00:1c.0 io port range because
from 0x4000 to 0x8000 could be used.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/setup-bus.c |   12 +-----------
 1 files changed, 1 insertions(+), 11 deletions(-)

diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index 2991a89..162edfb 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -1292,7 +1292,6 @@ pci_assign_unassigned_resources(void)
 	struct pci_dev_resource *fail_res;
 	unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM |
 				  IORESOURCE_PREFETCH;
-	unsigned long failed_type;
 	int pci_try_num = 1;
 
 	/* don't realloc if asked to do so */
@@ -1327,16 +1326,7 @@ again:
 	if (list_empty(&fail_head))
 		goto enable_and_dump;
 
-	failed_type = 0;
-	list_for_each_entry(fail_res, &fail_head, list)
-		failed_type |= fail_res->flags;
-
-	/*
-	 * io port are tight, don't try extra
-	 * or if reach the limit, don't want to try more
-	 */
-	failed_type &= type_mask;
-	if ((failed_type == IORESOURCE_IO) || (tried_times >= pci_try_num)) {
+	if (tried_times >= pci_try_num) {
 		free_list(&fail_head);
 		goto enable_and_dump;
 	}
-- 
1.7.7

[PATCH 2/4] PCI: Make pci bridge reallocating enabled/disabled

[Yinghai Lu]

Let the user could enable and disable with pci=realloc=on or pci=realloc=off

Also
1. move variable and functions near the place they are used.
2. change macro to function
3. change related functions and variable to static and _init
4. update parameter description accordingly.

-v2: still honor pci=realloc, and treat it as pci=realloc=on
     also use enum instead of ...
-v3: update kernel-paramenters.txt according to Jesse.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
---
 Documentation/kernel-parameters.txt |    9 +++++++--
 drivers/pci/pci.c                   |    4 +++-
 drivers/pci/pci.h                   |    2 +-
 drivers/pci/setup-bus.c             |   34 +++++++++++++++++++++++++++-------
 4 files changed, 38 insertions(+), 11 deletions(-)

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 7fb7a4b..7dc523e 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -2109,8 +2109,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 				the default.
 				off: Turn ECRC off
 				on: Turn ECRC on.
-		realloc		reallocate PCI resources if allocations done by BIOS
-				are erroneous.
+		realloc=	Enable/disable reallocating PCI bridge resources
+				if allocations done by BIOS are too small to
+				accommodate resources required by all child
+				devices.
+				off: Turn realloc off
+				on: Turn realloc on
+		realloc		same as realloc=on
 
 	pcie_aspm=	[PCIE] Forcibly enable or disable PCIe Active State Power
 			Management.
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 8f30736..e9f9dc1 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -3772,8 +3772,10 @@ static int __init pci_setup(char *str)
 				pci_no_msi();
 			} else if (!strcmp(str, "noaer")) {
 				pci_no_aer();
+			} else if (!strncmp(str, "realloc=", 8)) {
+				pci_realloc_get_opt(str + 8);
 			} else if (!strncmp(str, "realloc", 7)) {
-				pci_realloc();
+				pci_realloc_get_opt("on");
 			} else if (!strcmp(str, "nodomains")) {
 				pci_no_domains();
 			} else if (!strncmp(str, "cbiosize=", 9)) {
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index 586ac9b..1fc63b3 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -149,7 +149,7 @@ static inline void pci_no_msi(void) { }
 static inline void pci_msi_init_pci_dev(struct pci_dev *dev) { }
 #endif
 
-extern void pci_realloc(void);
+void pci_realloc_get_opt(char *);
 
 static inline int pci_no_d1d2(struct pci_dev *dev)
 {
diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index 162edfb..219722d 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -48,13 +48,6 @@ static void free_list(struct list_head *head)
 	}
 }
 
-int pci_realloc_enable = 0;
-#define pci_realloc_enabled() pci_realloc_enable
-void pci_realloc(void)
-{
-	pci_realloc_enable = 1;
-}
-
 /**
  * add_to_list() - add a new resource tracker to the list
  * @head:	Head of the list
@@ -1273,6 +1266,33 @@ static int __init pci_get_max_depth(void)
 	return depth;
 }
 
+/*
+ * -1: undefined, will auto detect later
+ *  0: disabled by user
+ *  1: disabled by auto detect
+ *  2: enabled by user
+ *  3: enabled by auto detect
+ */
+enum enable_type {
+	undefined = -1,
+	user_disabled,
+	auto_disabled,
+	user_enabled,
+	auto_enabled,
+};
+
+static enum enable_type pci_realloc_enable __initdata = undefined;
+void __init pci_realloc_get_opt(char *str)
+{
+	if (!strncmp(str, "off", 3))
+		pci_realloc_enable = user_disabled;
+	else if (!strncmp(str, "on", 2))
+		pci_realloc_enable = user_enabled;
+}
+static bool __init pci_realloc_enabled(void)
+{
+	return pci_realloc_enable >= user_enabled;
+}
 
 /*
  * first try will not touch pci bridge res
-- 
1.7.7

[PATCH 3/4] PCI: print out suggestion about using pci=realloc

[Yinghai Lu]

let user know they could try if pci=realloc could help.

-v2: update suggestion text.

Suggested-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/setup-bus.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index 219722d..e21e1c2 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -1347,6 +1347,9 @@ again:
 		goto enable_and_dump;
 
 	if (tried_times >= pci_try_num) {
+		if (pci_realloc_enable == undefined)
+			printk(KERN_INFO "Some PCI device resources are unassigned, try booting with pci=realloc\n");
+
 		free_list(&fail_head);
 		goto enable_and_dump;
 	}
-- 
1.7.7

[PATCH 4/4] PCI: only enable pci realloc when SRIOV bar is not assigned

[Yinghai Lu]

If bios does not assign those BAR or wrong address, then kernel will
try to do pci realloc.

in that case, user still can use pci=realloc=off to override it.

-v2: According to Jesse, adding one CONFIG option for distribution to
     disable it or enable it.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/Kconfig     |   10 ++++++++++
 drivers/pci/setup-bus.c |   28 ++++++++++++++++++++++++++++
 2 files changed, 38 insertions(+), 0 deletions(-)

diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig
index 37856f7..771a037 100644
--- a/drivers/pci/Kconfig
+++ b/drivers/pci/Kconfig
@@ -31,6 +31,16 @@ config PCI_DEBUG
 
 	  When in doubt, say N.
 
+config PCI_REALLOC_ENABLE_AUTO
+	bool "PCI Realloc Enable Auto"
+	depends on PCI
+	help
+	  Say Y here if you want the PCI core to detect if pci realloc
+	  need to be enabled. You can always use pci=realloc=on or
+	  pci=realloc=off to override it.
+
+	  When in doubt, say N.
+
 config PCI_STUB
 	tristate "PCI Stub driver"
 	depends on PCI
diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index e21e1c2..c9214a1 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -1294,6 +1294,31 @@ static bool __init pci_realloc_enabled(void)
 	return pci_realloc_enable >= user_enabled;
 }
 
+static void __init pci_realloc_detect(void)
+{
+#if defined(CONFIG_PCI_IOV) && defined(CONFIG_PCI_REALLOC_ENABLE_AUTO)
+	struct pci_dev *dev = NULL;
+
+	if (pci_realloc_enable != undefined)
+		return;
+
+	for_each_pci_dev(dev) {
+		int i;
+
+		for (i = PCI_IOV_RESOURCES; i <= PCI_IOV_RESOURCE_END; i++) {
+			struct resource *r = &dev->resource[i];
+
+			/* Not assigned, or rejected by kernel ? */
+			if (r->flags && !r->start) {
+				pci_realloc_enable = auto_enabled;
+
+				return;
+			}
+		}
+	}
+#endif
+}
+
 /*
  * first try will not touch pci bridge res
  * second  and later try will clear small leaf bridge res
@@ -1315,6 +1340,7 @@ pci_assign_unassigned_resources(void)
 	int pci_try_num = 1;
 
 	/* don't realloc if asked to do so */
+	pci_realloc_detect();
 	if (pci_realloc_enabled()) {
 		int max_depth = pci_get_max_depth();
 
@@ -1349,6 +1375,8 @@ again:
 	if (tried_times >= pci_try_num) {
 		if (pci_realloc_enable == undefined)
 			printk(KERN_INFO "Some PCI device resources are unassigned, try booting with pci=realloc\n");
+		else if (pci_realloc_enable == auto_enabled)
+			printk(KERN_INFO "Automatically enabled pci realloc, if you have problem, try booting with pci=realloc=off\n");
 
 		free_list(&fail_head);
 		goto enable_and_dump;
-- 
1.7.7

Re: [PATCH 4/4] PCI: only enable pci realloc when SRIOV bar is not assigned

[Jesse Barnes]

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On Thu, 23 Feb 2012 19:23:32 -0800
Yinghai Lu <yinghai@kernel.org> wrote:

> If bios does not assign those BAR or wrong address, then kernel will
> try to do pci realloc.
> 
> in that case, user still can use pci=realloc=off to override it.
> 
> -v2: According to Jesse, adding one CONFIG option for distribution to
>      disable it or enable it.
> 
> Signed-off-by: Yinghai Lu <yinghai@kernel.org>
> ---

Ok applied these, thanks for the cleanups Yinghai.

-- 
Jesse Barnes, Intel Open Source Technology Center

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