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

Baoquan He
2018-06-12T03:29:04Z

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(-)

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2.13.6