mbox series

[v5,0/4] resource: Use list_head to link sibling resource

Message ID 20180612032831.29747-1-bhe@redhat.com
Headers show
Series resource: Use list_head to link sibling resource | expand

Message

Baoquan He June 12, 2018, 3:28 a.m. UTC
This patchset is doing:
1) Replace struct resource's sibling list from singly linked list to
list_head. Clearing out those pointer operation within singly linked
list for better code readability.
2) Based on list_head replacement, add a new function
walk_system_ram_res_rev() which can does reversed iteration on
iomem_resource's siblings.
3) Change kexec_file loading to search system RAM top down for kernel
loadin, using walk_system_ram_res_rev().

Note:
This patchset passed testing on my kvm guest, x86_64 arch with network
enabling. The thing we need pay attetion to is that a root resource's
child member need be initialized specifically with LIST_HEAD_INIT() if
statically defined or INIT_LIST_HEAD() for dynamically definition. Here
Just like we do for iomem_resource/ioport_resource, or the change in
get_pci_domain_busn_res().


Links of the old post (Boris pointed out that we should use
https://lkml.kernel.org/r/Message-ID, while it can't be opened from
my side, so paste all of them here.):
v4:
https://lkml.kernel.org/r/20180507063224.24229-1-bhe@redhat.com
https://lkml.org/lkml/2018/5/7/36

v3:
https://lkml.kernel.org/r/20180419001848.3041-1-bhe@redhat.com
https://lkml.org/lkml/2018/4/18/767

v2:
https://lkml.kernel.org/r/20180408024724.16812-1-bhe@redhat.com
https://lkml.org/lkml/2018/4/7/169

v1:
https://lkml.kernel.org/r/20180322033722.9279-1-bhe@redhat.com
https://lkml.org/lkml/2018/3/21/952

Changelog:
v4->v5:
  Add new patch 0001 to move duplicated reparent_resources() to
  kernel/resource.c to make it be shared by different ARCH-es.

  Fix several code bugs reported by test robot on ARCH powerpc and
  microblaze.
v3->v4:
  Fix several bugs test robot reported. Rewrite cover letter and patch
  log according to reviewer's comment.

v2->v3:
  Rename resource functions first_child() and sibling() to
  resource_first_chils() and resource_sibling(). Dan suggested this.

  Move resource_first_chils() and resource_sibling() to linux/ioport.h
  and make them as inline function. Rob suggested this. Accordingly add
  linux/list.h including in linux/ioport.h, please help review if this
  bring efficiency degradation or code redundancy.

  The change on struct resource {} bring two pointers of size increase,
  mention this in git log to make it more specifically, Rob suggested
  this.

v1->v2:
  Use list_head instead to link resource siblings. This is suggested by
  Andrew.

  Rewrite walk_system_ram_res_rev() after list_head is taken to link
  resouce siblings.

Baoquan He (4):
  resource: Move reparent_resources() to kernel/resource.c and make it
    public
  resource: Use list_head to link sibling resource
  resource: add walk_system_ram_res_rev()
  kexec_file: Load kernel at top of system RAM if required

 arch/arm/plat-samsung/pm-check.c            |   6 +-
 arch/microblaze/pci/pci-common.c            |  41 +----
 arch/powerpc/kernel/pci-common.c            |  39 +----
 arch/sparc/kernel/ioport.c                  |   2 +-
 arch/xtensa/include/asm/pci-bridge.h        |   4 +-
 drivers/eisa/eisa-bus.c                     |   2 +
 drivers/gpu/drm/drm_memory.c                |   3 +-
 drivers/gpu/drm/gma500/gtt.c                |   5 +-
 drivers/hv/vmbus_drv.c                      |  52 +++---
 drivers/input/joystick/iforce/iforce-main.c |   4 +-
 drivers/nvdimm/namespace_devs.c             |   6 +-
 drivers/nvdimm/nd.h                         |   5 +-
 drivers/of/address.c                        |   4 +-
 drivers/parisc/lba_pci.c                    |   4 +-
 drivers/pci/host/vmd.c                      |   8 +-
 drivers/pci/probe.c                         |   2 +
 drivers/pci/setup-bus.c                     |   2 +-
 include/linux/ioport.h                      |  21 ++-
 kernel/kexec_file.c                         |   2 +
 kernel/resource.c                           | 259 ++++++++++++++++++----------
 20 files changed, 244 insertions(+), 227 deletions(-)

Comments

Baoquan He June 12, 2018, 3:34 a.m. UTC | #1
On 06/12/18 at 11:28am, Baoquan He wrote:
> reparent_resources() is duplicated in arch/microblaze/pci/pci-common.c
> and arch/powerpc/kernel/pci-common.c, so move it to kernel/resource.c
> so that it's shared. Later its code also need be updated using list_head
> to replace singly linked list.
> 
> Signed-off-by: Baoquan He <bhe@redhat.com>
> Cc: Michal Simek <monstr@monstr.eu>
> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
> Cc: Paul Mackerras <paulus@samba.org>
> Cc: Michael Ellerman <mpe@ellerman.id.au>
> ---
> v4->v5:
>   Fix several code bugs reported by test robot on ARCH powerpc and
>   microblaze.

Oops, I mistakenly added the patch change log of the current patch 0002
here. This patch is a newly added one.

> 
> v3->v4:
>   Fix several bugs test robot reported. And change patch log.
> 
> v2->v3:
>   Rename resource functions first_child() and sibling() to
>   resource_first_chils() and resource_sibling(). Dan suggested this.
> 
>   Move resource_first_chils() and resource_sibling() to linux/ioport.h
>   and make them as inline function. Rob suggested this. Accordingly add
>   linux/list.h including in linux/ioport.h, please help review if this
>   bring efficiency degradation or code redundancy.
> 
>   The change on struct resource {} bring two pointers of size increase,
>   mention this in git log to make it more specifically, Rob suggested
>   this.
> 
>  arch/microblaze/pci/pci-common.c | 37 -------------------------------------
>  arch/powerpc/kernel/pci-common.c | 35 -----------------------------------
>  include/linux/ioport.h           |  1 +
>  kernel/resource.c                | 36 ++++++++++++++++++++++++++++++++++++
>  4 files changed, 37 insertions(+), 72 deletions(-)
> 
> diff --git a/arch/microblaze/pci/pci-common.c b/arch/microblaze/pci/pci-common.c
> index f34346d56095..7899bafab064 100644
> --- a/arch/microblaze/pci/pci-common.c
> +++ b/arch/microblaze/pci/pci-common.c
> @@ -619,43 +619,6 @@ int pcibios_add_device(struct pci_dev *dev)
>  EXPORT_SYMBOL(pcibios_add_device);
>  
>  /*
> - * Reparent resource children of pr that conflict with res
> - * under res, and make res replace those children.
> - */
> -static int __init reparent_resources(struct resource *parent,
> -				     struct resource *res)
> -{
> -	struct resource *p, **pp;
> -	struct resource **firstpp = NULL;
> -
> -	for (pp = &parent->child; (p = *pp) != NULL; pp = &p->sibling) {
> -		if (p->end < res->start)
> -			continue;
> -		if (res->end < p->start)
> -			break;
> -		if (p->start < res->start || p->end > res->end)
> -			return -1;	/* not completely contained */
> -		if (firstpp == NULL)
> -			firstpp = pp;
> -	}
> -	if (firstpp == NULL)
> -		return -1;	/* didn't find any conflicting entries? */
> -	res->parent = parent;
> -	res->child = *firstpp;
> -	res->sibling = *pp;
> -	*firstpp = res;
> -	*pp = NULL;
> -	for (p = res->child; p != NULL; p = p->sibling) {
> -		p->parent = res;
> -		pr_debug("PCI: Reparented %s [%llx..%llx] under %s\n",
> -			 p->name,
> -			 (unsigned long long)p->start,
> -			 (unsigned long long)p->end, res->name);
> -	}
> -	return 0;
> -}
> -
> -/*
>   *  Handle resources of PCI devices.  If the world were perfect, we could
>   *  just allocate all the resource regions and do nothing more.  It isn't.
>   *  On the other hand, we cannot just re-allocate all devices, as it would
> diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c
> index fe9733ffffaa..926035bb378d 100644
> --- a/arch/powerpc/kernel/pci-common.c
> +++ b/arch/powerpc/kernel/pci-common.c
> @@ -1088,41 +1088,6 @@ resource_size_t pcibios_align_resource(void *data, const struct resource *res,
>  EXPORT_SYMBOL(pcibios_align_resource);
>  
>  /*
> - * Reparent resource children of pr that conflict with res
> - * under res, and make res replace those children.
> - */
> -static int reparent_resources(struct resource *parent,
> -				     struct resource *res)
> -{
> -	struct resource *p, **pp;
> -	struct resource **firstpp = NULL;
> -
> -	for (pp = &parent->child; (p = *pp) != NULL; pp = &p->sibling) {
> -		if (p->end < res->start)
> -			continue;
> -		if (res->end < p->start)
> -			break;
> -		if (p->start < res->start || p->end > res->end)
> -			return -1;	/* not completely contained */
> -		if (firstpp == NULL)
> -			firstpp = pp;
> -	}
> -	if (firstpp == NULL)
> -		return -1;	/* didn't find any conflicting entries? */
> -	res->parent = parent;
> -	res->child = *firstpp;
> -	res->sibling = *pp;
> -	*firstpp = res;
> -	*pp = NULL;
> -	for (p = res->child; p != NULL; p = p->sibling) {
> -		p->parent = res;
> -		pr_debug("PCI: Reparented %s %pR under %s\n",
> -			 p->name, p, res->name);
> -	}
> -	return 0;
> -}
> -
> -/*
>   *  Handle resources of PCI devices.  If the world were perfect, we could
>   *  just allocate all the resource regions and do nothing more.  It isn't.
>   *  On the other hand, we cannot just re-allocate all devices, as it would
> diff --git a/include/linux/ioport.h b/include/linux/ioport.h
> index da0ebaec25f0..dfdcd0bfe54e 100644
> --- a/include/linux/ioport.h
> +++ b/include/linux/ioport.h
> @@ -192,6 +192,7 @@ extern int allocate_resource(struct resource *root, struct resource *new,
>  struct resource *lookup_resource(struct resource *root, resource_size_t start);
>  int adjust_resource(struct resource *res, resource_size_t start,
>  		    resource_size_t size);
> +int reparent_resources(struct resource *parent, struct resource *res);
>  resource_size_t resource_alignment(struct resource *res);
>  static inline resource_size_t resource_size(const struct resource *res)
>  {
> diff --git a/kernel/resource.c b/kernel/resource.c
> index 30e1bc68503b..5e7c56d5d838 100644
> --- a/kernel/resource.c
> +++ b/kernel/resource.c
> @@ -983,6 +983,42 @@ int adjust_resource(struct resource *res, resource_size_t start,
>  }
>  EXPORT_SYMBOL(adjust_resource);
>  
> +/*
> + * Reparent resource children of pr that conflict with res
> + * under res, and make res replace those children.
> + */
> +static int reparent_resources(struct resource *parent,
> +				     struct resource *res)
> +{
> +	struct resource *p, **pp;
> +	struct resource **firstpp = NULL;
> +
> +	for (pp = &parent->child; (p = *pp) != NULL; pp = &p->sibling) {
> +		if (p->end < res->start)
> +			continue;
> +		if (res->end < p->start)
> +			break;
> +		if (p->start < res->start || p->end > res->end)
> +			return -1;	/* not completely contained */
> +		if (firstpp == NULL)
> +			firstpp = pp;
> +	}
> +	if (firstpp == NULL)
> +		return -1;	/* didn't find any conflicting entries? */
> +	res->parent = parent;
> +	res->child = *firstpp;
> +	res->sibling = *pp;
> +	*firstpp = res;
> +	*pp = NULL;
> +	for (p = res->child; p != NULL; p = p->sibling) {
> +		p->parent = res;
> +		pr_debug("PCI: Reparented %s %pR under %s\n",
> +			 p->name, p, res->name);
> +	}
> +	return 0;
> +}
> +EXPORT_SYMBOL(reparent_resources);
> +
>  static void __init __reserve_region_with_split(struct resource *root,
>  		resource_size_t start, resource_size_t end,
>  		const char *name)
> -- 
> 2.13.6
> 
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html