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* powerpc: various straight conversions from module.h --> export.hPaul Gortmaker2011-10-311-1/+1
| | | | | | | | | All these files were including module.h just for the basic EXPORT_SYMBOL infrastructure. We can shift them off to the export.h header which is a way smaller footprint and thus realize some compile time gains. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
* powerpc: is_hugepage_only_range() must account for both 4kB and 64kB slicesDave Kleikamp2009-01-161-1/+10
| | | | | | | | | | | powerpc: is_hugepage_only_range() must account for both 4kB and 64kB slices The subpage_prot syscall fails on second and subsequent calls for a given region, because is_hugepage_only_range() is mis-identifying the 4 kB slices when the process has a 64 kB page size. Signed-off-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* Merge commit 'origin/master'Benjamin Herrenschmidt2008-07-161-1/+1
|\ | | | | | | | | | | | | | | Manual merge of: arch/powerpc/Kconfig arch/powerpc/kernel/stacktrace.c arch/powerpc/mm/slice.c arch/ppc/kernel/smp.c
| * on_each_cpu(): kill unused 'retry' parameterJens Axboe2008-06-261-1/+1
| | | | | | | | | | | | | | | | | | It's not even passed on to smp_call_function() anymore, since that was removed. So kill it. Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* | powerpc: Only demote individual slices rather than whole processPaul Mackerras2008-07-011-44/+133
|/ | | | | | | | | | | | | | | | | | | | | At present, if we have a kernel with a 64kB page size, and some process maps something that has to be mapped with 4kB pages (such as a cache-inhibited mapping on POWER5+, or the eHCA infiniband queue-pair pages), we change the process to use 4kB pages everywhere. This hurts the performance of HPC programs that access eHCA from userspace. With this patch, the kernel will only demote the slice(s) containing the eHCA or cache-inhibited mappings, leaving the remaining slices able to use 64kB hardware pages. This also changes the slice_get_unmapped_area code so that it is willing to place a 64k-page mapping into (or across) a 4k-page slice if there is no better alternative, i.e. if the program specified MAP_FIXED or if there is not sufficient space available in slices that are either empty or already have 64k-page mappings in them. Signed-off-by: Paul Mackerras <paulus@samba.org> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* spin_lock_unlocked cleanupsRoel Kluin2007-10-171-1/+1
| | | | | | | | | Replace some SPIN_LOCK_UNLOCKED with DEFINE_SPINLOCK Signed-off-by: Roel Kluin <12o3l@tiscali.nl> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [POWERPC] Fix non HUGETLB_PAGE build warningStephen Rothwell2007-08-171-0/+1
| | | | | | | | arch/powerpc/mm/mmu_context_64.c: In function 'init_new_context': arch/powerpc/mm/mmu_context_64.c:31: warning: unused variable 'new_context' Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
* [POWERPC] Fix size check for hugetlbfsBenjamin Herrenschmidt2007-08-101-0/+2
| | | | | | | | | | | | My "slices" address space management code that was added in the 2.6.22 implementation of get_unmapped_area() doesn't properly check that the size is a multiple of the requested page size. This allows userland to create VMAs that aren't a multiple of the huge page size with hugetlbfs (since hugetlbfs entirely relies on get_unmapped_area() to do that checking) which leads to a kernel BUG() when such areas are torn down. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
* [POWERPC] Introduce address space "slices"Benjamin Herrenschmidt2007-05-091-0/+633
The basic issue is to be able to do what hugetlbfs does but with different page sizes for some other special filesystems; more specifically, my need is: - Huge pages - SPE local store mappings using 64K pages on a 4K base page size kernel on Cell - Some special 4K segments in 64K-page kernels for mapping a dodgy type of powerpc-specific infiniband hardware that requires 4K MMU mappings for various reasons I won't explain here. The main issues are: - To maintain/keep track of the page size per "segment" (as we can only have one page size per segment on powerpc, which are 256MB divisions of the address space). - To make sure special mappings stay within their allotted "segments" (including MAP_FIXED crap) - To make sure everybody else doesn't mmap/brk/grow_stack into a "segment" that is used for a special mapping Some of the necessary mechanisms to handle that were present in the hugetlbfs code, but mostly in ways not suitable for anything else. The patch relies on some changes to the generic get_unmapped_area() that just got merged. It still hijacks hugetlb callbacks here or there as the generic code hasn't been entirely cleaned up yet but that shouldn't be a problem. So what is a slice ? Well, I re-used the mechanism used formerly by our hugetlbfs implementation which divides the address space in "meta-segments" which I called "slices". The division is done using 256MB slices below 4G, and 1T slices above. Thus the address space is divided currently into 16 "low" slices and 16 "high" slices. (Special case: high slice 0 is the area between 4G and 1T). Doing so simplifies significantly the tracking of segments and avoids having to keep track of all the 256MB segments in the address space. While I used the "concepts" of hugetlbfs, I mostly re-implemented everything in a more generic way and "ported" hugetlbfs to it. Slices can have an associated page size, which is encoded in the mmu context and used by the SLB miss handler to set the segment sizes. The hash code currently doesn't care, it has a specific check for hugepages, though I might add a mechanism to provide per-slice hash mapping functions in the future. The slice code provide a pair of "generic" get_unmapped_area() (bottomup and topdown) functions that should work with any slice size. There is some trickiness here so I would appreciate people to have a look at the implementation of these and let me know if I got something wrong. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
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