| Message ID | 1495525511-202465-1-git-send-email-shawn.lin@rock-chips.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi Shawn,
[auto build test ERROR on pci/next]
[also build test ERROR on v4.12-rc2 next-20170523]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
url: https://github.com/0day-ci/linux/commits/Shawn-Lin/PCI-use-IDA-to-manage-domain-number-if-not-getting-it-from-DT/20170524-095618
base: https://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git next
config: x86_64-kexec (attached as .config)
compiler: gcc-6 (Debian 6.2.0-3) 6.2.0 20160901
reproduce:
# save the attached .config to linux build tree
make ARCH=x86_64
All errors (new ones prefixed by >>):
drivers/pci/pci.c: In function 'pci_put_old_domain_nr':
>> drivers/pci/pci.c:5357:38: error: 'struct pci_bus' has no member named 'domain_nr'
ida_simple_remove(&__domain_nr, bus->domain_nr);
^~
vim +5357 drivers/pci/pci.c
5351 return ida_simple_get(&__domain_nr, 0, sizeof(u64), GFP_KERNEL);
5352 }
5353
5354 void pci_put_old_domain_nr(struct pci_bus *bus)
5355 {
5356 if (ida_domain)
> 5357 ida_simple_remove(&__domain_nr, bus->domain_nr);
5358 }
5359
5360 #ifdef CONFIG_PCI_DOMAINS_GENERIC
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
Hi Shawn, On Tue, May 23, 2017 at 03:45:11PM +0800, Shawn Lin wrote: > If not getting domain number from DT, the domain number will > keep increasing once doing unbind/bind RC drivers. This could > introduce pointless tree view of lspci as shows below: > > -+-[0001:00]---00.0-[01]----00.0 > \-[0000:00]- > > The more test we do, the lengthier it would be. The more serious > issue is that if attaching two hierarchies for two different domains > belonging to two root bridges, so when doing unbind/bind test for one > of them and keep the other, then the domain number would finally > overflow and make the two hierarchies of devices share the some domain > number but actually they shouldn't. So it looks like we need to invent > a new indexing ID mechanism to manage domain number. This patch > introduces idr to achieve our purpose. > > Cc: Brian Norris <briannorris@chromium.org> > Cc: Jeffy Chen <jeffy.chen@rock-chips.com> > Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com> > > --- > > Changes in v3: > - make ida_domain a system-wide property and check it in the code to > combine with use_dt_domains. Also update the comment there. > > Changes in v2: > - add a remove wrapper > - rename use_dt_domains to ida_domain and set this bit > in pci_get_new_domain_nr and test it in the remove wrapper. > > drivers/pci/pci.c | 42 ++++++++++++++++++++++++++++-------------- > drivers/pci/remove.c | 2 ++ > include/linux/pci.h | 8 ++++++-- > 3 files changed, 36 insertions(+), 16 deletions(-) > > diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c > index b01bd5b..e5f5db0 100644 > --- a/drivers/pci/pci.c > +++ b/drivers/pci/pci.c > @@ -11,6 +11,7 @@ > #include <linux/kernel.h> > #include <linux/delay.h> > #include <linux/dmi.h> > +#include <linux/idr.h> > #include <linux/init.h> > #include <linux/of.h> > #include <linux/of_pci.h> > @@ -5340,15 +5341,25 @@ static void pci_no_domains(void) > } > > #ifdef CONFIG_PCI_DOMAINS > -static atomic_t __domain_nr = ATOMIC_INIT(-1); > +DEFINE_IDA(__domain_nr); Should be static. > -int pci_get_new_domain_nr(void) > +/* get domain number from IDA */ > +static bool ida_domain = true; Reorder so "ida_domain" precedes the data structure it controls. > +int pci_get_new_domain_nr(struct pci_bus *bus) > +{ > + return ida_simple_get(&__domain_nr, 0, sizeof(u64), GFP_KERNEL); > +} > + > +void pci_put_old_domain_nr(struct pci_bus *bus) s/pci_put_old_domain_nr/pci_put_domain_nr/ > { > - return atomic_inc_return(&__domain_nr); > + if (ida_domain) > + ida_simple_remove(&__domain_nr, bus->domain_nr); > } > > #ifdef CONFIG_PCI_DOMAINS_GENERIC > -static int of_pci_bus_find_domain_nr(struct device *parent) > +static int of_pci_bus_find_domain_nr(struct pci_bus *bus, > + struct device *parent) > { > static int use_dt_domains = -1; > int domain = -1; > @@ -5361,19 +5372,21 @@ static int of_pci_bus_find_domain_nr(struct device *parent) > * If DT domain property is valid (domain >= 0) and > * use_dt_domains != 0, the DT assignment is valid since this means > * we have not previously allocated a domain number by using > - * pci_get_new_domain_nr(); we should also update use_dt_domains to > - * 1, to indicate that we have just assigned a domain number from > - * DT. > + * pci_get_new_domain_nr(), so we should set ida_domain to false to > + * indicate that we don't allocate domain from idr; we should also > + * update use_dt_domains to 1, to indicate that we have just assigned > + * a domain number from DT. > * > * If DT domain property value is not valid (ie domain < 0), and we > * have not previously assigned a domain number from DT > - * (use_dt_domains != 1) we should assign a domain number by > - * using the: > + * (use_dt_domains != 1 && ida_domain != false) we should assign a > + * domain number by using the: > * > * pci_get_new_domain_nr() > * > - * API and update the use_dt_domains value to keep track of method we > - * are using to assign domain numbers (use_dt_domains = 0). > + * API and update the use_dt_domains and ida_domain value to keep track > + * of method we are using to assign domain numbers (use_dt_domains = 0 > + * and ida_domain = true). > * > * All other combinations imply we have a platform that is trying > * to mix domain numbers obtained from DT and pci_get_new_domain_nr(), > @@ -5383,9 +5396,10 @@ static int of_pci_bus_find_domain_nr(struct device *parent) > */ > if (domain >= 0 && use_dt_domains) { > use_dt_domains = 1; > - } else if (domain < 0 && use_dt_domains != 1) { > + ida_domain = false; > + } else if (domain < 0 && use_dt_domains != 1 && ida_domain != false) { > use_dt_domains = 0; > - domain = pci_get_new_domain_nr(); > + domain = pci_get_new_domain_nr(bus); These comments and logic are too complicated for my puny brain. Much of this was pre-existing, of course. Surely there's a simpler way? 1) If we're using ACPI, every host bridge must have a _SEG method, and it supplies the domain. We ignore any bridge without _SEG. 2) If we're using DT, every host bridge must supply "linux,pci-domain", and it supplies the domain. We ignore any bridge without "linux,pci-domain". 3) Otherwise, we always use IDA. > } else { > dev_err(parent, "Node %s has inconsistent \"linux,pci-domain\" property in DT\n", > parent->of_node->full_name); > @@ -5397,7 +5411,7 @@ static int of_pci_bus_find_domain_nr(struct device *parent) > > int pci_bus_find_domain_nr(struct pci_bus *bus, struct device *parent) > { > - return acpi_disabled ? of_pci_bus_find_domain_nr(parent) : > + return acpi_disabled ? of_pci_bus_find_domain_nr(bus, parent) : > acpi_pci_bus_find_domain_nr(bus); > } > #endif > diff --git a/drivers/pci/remove.c b/drivers/pci/remove.c > index 73a03d3..1bbbb37 100644 > --- a/drivers/pci/remove.c > +++ b/drivers/pci/remove.c > @@ -157,6 +157,8 @@ void pci_remove_root_bus(struct pci_bus *bus) > list_for_each_entry_safe(child, tmp, > &bus->devices, bus_list) > pci_remove_bus_device(child); > + > + pci_put_old_domain_nr(bus); In your current patch, ida_domain defaults to true, and it is only set to false in of_pci_bus_find_domain_nr(), which is only called when ACPI is disabled. Therefore, ida_domain will be true when we're using ACPI, and I think pci_put_old_domain_nr() will erroneously remove domains from tha IDA. > pci_remove_bus(bus); > host_bridge->bus = NULL; > > diff --git a/include/linux/pci.h b/include/linux/pci.h > index 33c2b0b..9296e31 100644 > --- a/include/linux/pci.h > +++ b/include/linux/pci.h > @@ -1445,13 +1445,17 @@ static inline int pci_enable_ptm(struct pci_dev *dev, u8 *granularity) > * configuration space. > */ > #ifdef CONFIG_PCI_DOMAINS > +extern struct ida __domain_nr; > extern int pci_domains_supported; > -int pci_get_new_domain_nr(void); > +int pci_get_new_domain_nr(struct pci_bus *bus); > +void pci_put_old_domain_nr(struct pci_bus *bus); > #else > enum { pci_domains_supported = 0 }; > static inline int pci_domain_nr(struct pci_bus *bus) { return 0; } > static inline int pci_proc_domain(struct pci_bus *bus) { return 0; } > -static inline int pci_get_new_domain_nr(void) { return -ENOSYS; } > +static inline int pci_get_new_domain_nr(struct pci_bus *bus) > +{ return -ENOSYS; } > +static inline void pci_put_old_domain_nr(struct pci_bus *bus) { } > #endif /* CONFIG_PCI_DOMAINS */ > > /* > -- > 1.9.1 > >
Hi Bjorn, On 2017/5/25 6:30, Bjorn Helgaas wrote: > Hi Shawn, > > On Tue, May 23, 2017 at 03:45:11PM +0800, Shawn Lin wrote: [...] >> + domain = pci_get_new_domain_nr(bus); > > These comments and logic are too complicated for my puny brain. Much of > this was pre-existing, of course. Surely there's a simpler way? yup, I think we could simplify the code. > > 1) If we're using ACPI, every host bridge must have a _SEG method, and it > supplies the domain. We ignore any bridge without _SEG. > > 2) If we're using DT, every host bridge must supply "linux,pci-domain", and > it supplies the domain. We ignore any bridge without "linux,pci-domain". > > 3) Otherwise, we always use IDA. I plan to create a new function to allocate domain number using IDA as then we don't touch the logic of of_pci_bus_find_domain_nr, and the name of of_pci_bus_find_domain_nr explicitly say that the domain number comes from DT. Then I could put the condition check inside the pci_bus_find_domain_nr as your suggested. Does it looks ok to you? > >> } else { >> dev_err(parent, "Node %s has inconsistent \"linux,pci-domain\" property in DT\n", [...] >> pci_remove_bus_device(child); >> + >> + pci_put_old_domain_nr(bus); > > In your current patch, ida_domain defaults to true, and it is only set > to false in of_pci_bus_find_domain_nr(), which is only called when > ACPI is disabled. Therefore, ida_domain will be true when we're using > ACPI, and I think pci_put_old_domain_nr() will erroneously remove > domains from tha IDA. > woops, I forgot to check the ACPI cases. >> pci_remove_bus(bus); >> host_bridge->bus = NULL; >> >> diff --git a/include/linux/pci.h b/include/linux/pci.h >> index 33c2b0b..9296e31 100644 >> --- a/include/linux/pci.h >> +++ b/include/linux/pci.h >> @@ -1445,13 +1445,17 @@ static inline int pci_enable_ptm(struct pci_dev *dev, u8 *granularity) >> * configuration space. >> */ >> #ifdef CONFIG_PCI_DOMAINS >> +extern struct ida __domain_nr; >> extern int pci_domains_supported; >> -int pci_get_new_domain_nr(void); >> +int pci_get_new_domain_nr(struct pci_bus *bus); >> +void pci_put_old_domain_nr(struct pci_bus *bus); >> #else >> enum { pci_domains_supported = 0 }; >> static inline int pci_domain_nr(struct pci_bus *bus) { return 0; } >> static inline int pci_proc_domain(struct pci_bus *bus) { return 0; } >> -static inline int pci_get_new_domain_nr(void) { return -ENOSYS; } >> +static inline int pci_get_new_domain_nr(struct pci_bus *bus) >> +{ return -ENOSYS; } >> +static inline void pci_put_old_domain_nr(struct pci_bus *bus) { } >> #endif /* CONFIG_PCI_DOMAINS */ >> >> /* >> -- >> 1.9.1 >> >> > > >
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index b01bd5b..e5f5db0 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -11,6 +11,7 @@ #include <linux/kernel.h> #include <linux/delay.h> #include <linux/dmi.h> +#include <linux/idr.h> #include <linux/init.h> #include <linux/of.h> #include <linux/of_pci.h> @@ -5340,15 +5341,25 @@ static void pci_no_domains(void) } #ifdef CONFIG_PCI_DOMAINS -static atomic_t __domain_nr = ATOMIC_INIT(-1); +DEFINE_IDA(__domain_nr); -int pci_get_new_domain_nr(void) +/* get domain number from IDA */ +static bool ida_domain = true; + +int pci_get_new_domain_nr(struct pci_bus *bus) +{ + return ida_simple_get(&__domain_nr, 0, sizeof(u64), GFP_KERNEL); +} + +void pci_put_old_domain_nr(struct pci_bus *bus) { - return atomic_inc_return(&__domain_nr); + if (ida_domain) + ida_simple_remove(&__domain_nr, bus->domain_nr); } #ifdef CONFIG_PCI_DOMAINS_GENERIC -static int of_pci_bus_find_domain_nr(struct device *parent) +static int of_pci_bus_find_domain_nr(struct pci_bus *bus, + struct device *parent) { static int use_dt_domains = -1; int domain = -1; @@ -5361,19 +5372,21 @@ static int of_pci_bus_find_domain_nr(struct device *parent) * If DT domain property is valid (domain >= 0) and * use_dt_domains != 0, the DT assignment is valid since this means * we have not previously allocated a domain number by using - * pci_get_new_domain_nr(); we should also update use_dt_domains to - * 1, to indicate that we have just assigned a domain number from - * DT. + * pci_get_new_domain_nr(), so we should set ida_domain to false to + * indicate that we don't allocate domain from idr; we should also + * update use_dt_domains to 1, to indicate that we have just assigned + * a domain number from DT. * * If DT domain property value is not valid (ie domain < 0), and we * have not previously assigned a domain number from DT - * (use_dt_domains != 1) we should assign a domain number by - * using the: + * (use_dt_domains != 1 && ida_domain != false) we should assign a + * domain number by using the: * * pci_get_new_domain_nr() * - * API and update the use_dt_domains value to keep track of method we - * are using to assign domain numbers (use_dt_domains = 0). + * API and update the use_dt_domains and ida_domain value to keep track + * of method we are using to assign domain numbers (use_dt_domains = 0 + * and ida_domain = true). * * All other combinations imply we have a platform that is trying * to mix domain numbers obtained from DT and pci_get_new_domain_nr(), @@ -5383,9 +5396,10 @@ static int of_pci_bus_find_domain_nr(struct device *parent) */ if (domain >= 0 && use_dt_domains) { use_dt_domains = 1; - } else if (domain < 0 && use_dt_domains != 1) { + ida_domain = false; + } else if (domain < 0 && use_dt_domains != 1 && ida_domain != false) { use_dt_domains = 0; - domain = pci_get_new_domain_nr(); + domain = pci_get_new_domain_nr(bus); } else { dev_err(parent, "Node %s has inconsistent \"linux,pci-domain\" property in DT\n", parent->of_node->full_name); @@ -5397,7 +5411,7 @@ static int of_pci_bus_find_domain_nr(struct device *parent) int pci_bus_find_domain_nr(struct pci_bus *bus, struct device *parent) { - return acpi_disabled ? of_pci_bus_find_domain_nr(parent) : + return acpi_disabled ? of_pci_bus_find_domain_nr(bus, parent) : acpi_pci_bus_find_domain_nr(bus); } #endif diff --git a/drivers/pci/remove.c b/drivers/pci/remove.c index 73a03d3..1bbbb37 100644 --- a/drivers/pci/remove.c +++ b/drivers/pci/remove.c @@ -157,6 +157,8 @@ void pci_remove_root_bus(struct pci_bus *bus) list_for_each_entry_safe(child, tmp, &bus->devices, bus_list) pci_remove_bus_device(child); + + pci_put_old_domain_nr(bus); pci_remove_bus(bus); host_bridge->bus = NULL; diff --git a/include/linux/pci.h b/include/linux/pci.h index 33c2b0b..9296e31 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -1445,13 +1445,17 @@ static inline int pci_enable_ptm(struct pci_dev *dev, u8 *granularity) * configuration space. */ #ifdef CONFIG_PCI_DOMAINS +extern struct ida __domain_nr; extern int pci_domains_supported; -int pci_get_new_domain_nr(void); +int pci_get_new_domain_nr(struct pci_bus *bus); +void pci_put_old_domain_nr(struct pci_bus *bus); #else enum { pci_domains_supported = 0 }; static inline int pci_domain_nr(struct pci_bus *bus) { return 0; } static inline int pci_proc_domain(struct pci_bus *bus) { return 0; } -static inline int pci_get_new_domain_nr(void) { return -ENOSYS; } +static inline int pci_get_new_domain_nr(struct pci_bus *bus) +{ return -ENOSYS; } +static inline void pci_put_old_domain_nr(struct pci_bus *bus) { } #endif /* CONFIG_PCI_DOMAINS */ /*
If not getting domain number from DT, the domain number will keep increasing once doing unbind/bind RC drivers. This could introduce pointless tree view of lspci as shows below: -+-[0001:00]---00.0-[01]----00.0 \-[0000:00]- The more test we do, the lengthier it would be. The more serious issue is that if attaching two hierarchies for two different domains belonging to two root bridges, so when doing unbind/bind test for one of them and keep the other, then the domain number would finally overflow and make the two hierarchies of devices share the some domain number but actually they shouldn't. So it looks like we need to invent a new indexing ID mechanism to manage domain number. This patch introduces idr to achieve our purpose. Cc: Brian Norris <briannorris@chromium.org> Cc: Jeffy Chen <jeffy.chen@rock-chips.com> Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com> --- Changes in v3: - make ida_domain a system-wide property and check it in the code to combine with use_dt_domains. Also update the comment there. Changes in v2: - add a remove wrapper - rename use_dt_domains to ida_domain and set this bit in pci_get_new_domain_nr and test it in the remove wrapper. drivers/pci/pci.c | 42 ++++++++++++++++++++++++++++-------------- drivers/pci/remove.c | 2 ++ include/linux/pci.h | 8 ++++++-- 3 files changed, 36 insertions(+), 16 deletions(-)