Messages in this thread | | | Date | Fri, 6 Mar 2009 09:06:35 +0100 | From | Ingo Molnar <> | Subject | Re: [GIT PULL] x86, percpu: implement and use reserved percpu alloc |
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* Tejun Heo <tj@kernel.org> wrote:
> Hello, > > Please pull from the following git vector. > > git://git.kernel.org/pub/scm/linux/kernel/git/tj/misc.git tj-percpu > > This patchset implements reserved percpu alloc from the first > chunk and uses it for static perpcu variables in modules on > x86_64. This is necessary because x86_64 expects symbols to > be relocatable using 32bit relocations but dynamic percpu > allocation does not guarantee it leading to relocation > overflow during module load. > > This can happen to any of the x86_64 percpu first chunk > allocators but the embedding allocator is most likely to > trigger it as the first chunk is located in the normal kernel > memory allocation area while all the other chunks will be > allocated in the vmalloc area which is very far from the first > chunk. > > This type of reservation will be necessary for other > architectures too where addressing mode used for percpu acess > uses offsets with limited range to access symbols (e.g. ia64 > w/ the magic 64k percpu page). > > This problem was first reported and bisected by Mike > Galbraith[2]. > > This patchset is against the current x86/core/percpu[1] and contains > the following patches. > > 0001-percpu-clean-up-percpu-constants.patch > 0002-percpu-cosmetic-renames-in-pcpu_setup_first_chunk.patch > 0003-percpu-improve-first-chunk-initial-area-map-handlin.patch > 0004-percpu-use-negative-for-auto-for-pcpu_setup_first_c.patch > 0005-x86-make-embedding-percpu-allocator-return-excessiv.patch > 0006-percpu-add-an-indirection-ptr-for-chunk-page-map-ac.patch > 0007-percpu-module-implement-reserved-allocation-and-us.patch > 0008-x86-percpu-setup-reserved-percpu-area-for-x86_64.patch > > 0001-0004 makes misc updates to percpu in preparation of later > changes. 0005 fixes a case where excessive memory can be set > aside in the first chunk when using the embedding allocator. > 0006-0008 implement reserved allocation and use it for x86_64. > > Bryan Wu, can you please review #0001? It contains small > change in blackfin. It's mostly trivial but just in case. > > Diffstat follows. > > arch/blackfin/include/asm/percpu.h | 10 - > arch/x86/kernel/setup_percpu.c | 73 +++++++--- > include/linux/percpu.h | 60 +++----- > kernel/module.c | 2 > mm/percpu.c | 267 ++++++++++++++++++++++++++----------- > 5 files changed, 274 insertions(+), 138 deletions(-)
Pulled, thanks Tejun!
Ingo
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