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* Merge branch 'devel' of master.kernel.org:/home/rmk/linux-2.6-armLinus Torvalds2009-03-28
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm: (422 commits) [ARM] 5435/1: fix compile warning in sanity_check_meminfo() [ARM] 5434/1: ARM: OMAP: Fix mailbox compile for 24xx [ARM] pxa: fix the bad assumption that PCMCIA sockets always start with 0 [ARM] pxa: fix Colibri PXA300 and PXA320 LCD backlight pins imxfb: Fix TFT mode i.MX21/27: remove ifdef CONFIG_FB_IMX imxfb: add clock support mxc: add arch_reset() function clkdev: add possibility to get a clock based on the device name i.MX1: remove fb support from mach-imx [ARM] pxa: build arch/arm/plat-pxa/mfp.c only when PXA3xx or ARCH_MMP defined Gemini: Add support for Teltonika RUT100 Gemini: gpiolib based GPIO support v2 MAINTAINERS: add myself as Gemini architecture maintainer ARM: Add Gemini architecture v3 [ARM] OMAP: Fix compile for omap2_init_common_hw() MAINTAINERS: Add myself as Faraday ARM core variant maintainer ARM: Add support for FA526 v2 [ARM] acorn,ebsa110,footbridge,integrator,sa1100: Convert asm/io.h to linux/io.h [ARM] collie: fix two minor formatting nits ...
| * Merge branch 'origin' into develRussell King2009-03-28
| |\ | | | | | | | | | | | | Conflicts: sound/soc/pxa/pxa2xx-i2s.c
| * \ Merge branch 'for-next' of ↵Russell King2009-03-25
| |\ \ | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6 into devel
| * | | highmem: atomic highmem kmap page pinningNicolas Pitre2009-03-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Most ARM machines have a non IO coherent cache, meaning that the dma_map_*() set of functions must clean and/or invalidate the affected memory manually before DMA occurs. And because the majority of those machines have a VIVT cache, the cache maintenance operations must be performed using virtual addresses. When a highmem page is kunmap'd, its mapping (and cache) remains in place in case it is kmap'd again. However if dma_map_page() is then called with such a page, some cache maintenance on the remaining mapping must be performed. In that case, page_address(page) is non null and we can use that to synchronize the cache. It is unlikely but still possible for kmap() to race and recycle the virtual address obtained above, and use it for another page before some on-going cache invalidation loop in dma_map_page() is done. In that case, the new mapping could end up with dirty cache lines for another page, and the unsuspecting cache invalidation loop in dma_map_page() might simply discard those dirty cache lines resulting in data loss. For example, let's consider this sequence of events: - dma_map_page(..., DMA_FROM_DEVICE) is called on a highmem page. --> - vaddr = page_address(page) is non null. In this case it is likely that the page has valid cache lines associated with vaddr. Remember that the cache is VIVT. --> for (i = vaddr; i < vaddr + PAGE_SIZE; i += 32) invalidate_cache_line(i); *** preemption occurs in the middle of the loop above *** - kmap_high() is called for a different page. --> - last_pkmap_nr wraps to zero and flush_all_zero_pkmaps() is called. The pkmap_count value for the page passed to dma_map_page() above happens to be 1, so the page is unmapped. But prior to that, flush_cache_kmaps() cleared the cache for it. So far so good. - A fresh pkmap entry is assigned for this kmap request. The Murphy law says this pkmap entry will eventually happen to use the same vaddr as the one which used to belong to the other page being processed by dma_map_page() in the preempted thread above. - The kmap_high() caller start dirtying the cache using the just assigned virtual mapping for its page. *** the first thread is rescheduled *** - The for(...) loop is resumed, but now cached data belonging to a different physical page is being discarded ! And this is not only a preemption issue as ARM can be SMP as well, making the above scenario just as likely. Hence the need for some kind of pkmap page pinning which can be used in any context, primarily for the benefit of dma_map_page() on ARM. This provides the necessary interface to cope with the above issue if ARCH_NEEDS_KMAP_HIGH_GET is defined, otherwise the resulting code is unchanged. Signed-off-by: Nicolas Pitre <nico@marvell.com> Reviewed-by: MinChan Kim <minchan.kim@gmail.com> Acked-by: Andrew Morton <akpm@linux-foundation.org>
* | | | Merge branch 'core/percpu' into percpu-cpumask-x86-for-linus-2Ingo Molnar2009-03-27
|\ \ \ \ | |_|_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Conflicts: arch/parisc/kernel/irq.c arch/x86/include/asm/fixmap_64.h arch/x86/include/asm/setup.h kernel/irq/handle.c Semantic merge: arch/x86/include/asm/fixmap.h Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | percpu: fix spurious alignment WARN in legacy SMP percpu allocatorTejun Heo2009-03-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: remove spurious WARN on legacy SMP percpu allocator Commit f2a8205c4ef1af917d175c36a4097ae5587791c8 incorrectly added too tight WARN_ON_ONCE() on alignments for UP and legacy SMP percpu allocator. Commit e317603694bfd17b28a40de9d65e1a4ec12f816e fixed it for UP but legacy SMP allocator was forgotten. Fix it. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Sachin P. Sant <sachinp@in.ibm.com>
| * | | percpu: generalize embedding first chunk setup helperTejun Heo2009-03-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: code reorganization Separate out embedding first chunk setup helper from x86 embedding first chunk allocator and put it in mm/percpu.c. This will be used by the default percpu first chunk allocator and possibly by other archs. Signed-off-by: Tejun Heo <tj@kernel.org>
| * | | percpu: more flexibility for @dyn_size of pcpu_setup_first_chunk()Tejun Heo2009-03-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: cleanup, more flexibility for first chunk init Non-negative @dyn_size used to be allowed iff @unit_size wasn't auto. This restriction stemmed from implementation detail and made things a bit less intuitive. This patch allows @dyn_size to be specified regardless of @unit_size and swaps the positions of @dyn_size and @unit_size so that the parameter order makes more sense (static, reserved and dyn sizes followed by enclosing unit_size). While at it, add @unit_size >= PCPU_MIN_UNIT_SIZE sanity check. Signed-off-by: Tejun Heo <tj@kernel.org>
| * | | percpu: make x86 addr <-> pcpu ptr conversion macros genericTejun Heo2009-03-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: generic addr <-> pcpu ptr conversion macros There's nothing arch specific about x86 __addr_to_pcpu_ptr() and __pcpu_ptr_to_addr(). With proper __per_cpu_load and __per_cpu_start defined, they'll do the right thing regardless of actual layout. Move these macros from arch/x86/include/asm/percpu.h to mm/percpu.c and allow archs to override it as necessary. Signed-off-by: Tejun Heo <tj@kernel.org>
| * | | percpu: finer grained locking to break deadlock and allow atomic freeTejun Heo2009-03-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: fix deadlock and allow atomic free Percpu allocation always uses GFP_KERNEL and whole alloc/free paths were protected by single mutex. All percpu allocations have been from GFP_KERNEL-safe context and the original allocator had this assumption too. However, by protecting both alloc and free paths with the same mutex, the new allocator creates free -> alloc -> GFP_KERNEL dependency which the original allocator didn't have. This can lead to deadlock if free is called from FS or IO paths. Also, in general, allocators are expected to allow free to be called from atomic context. This patch implements finer grained locking to break the deadlock and allow atomic free. For details, please read the "Synchronization rules" comment. While at it, also add CONTEXT: to function comments to describe which context they expect to be called from and what they do to it. This problem was reported by Thomas Gleixner and Peter Zijlstra. http://thread.gmane.org/gmane.linux.kernel/802384 Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Thomas Gleixner <tglx@linutronix.de> Reported-by: Peter Zijlstra <peterz@infradead.org>
| * | | percpu: move fully free chunk reclamation into a workTejun Heo2009-03-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: code reorganization for later changes Do fully free chunk reclamation using a work. This change is to prepare for locking changes. Signed-off-by: Tejun Heo <tj@kernel.org>
| * | | percpu: move chunk area map extension out of area allocationTejun Heo2009-03-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: code reorganization for later changes Separate out chunk area map extension into a separate function - pcpu_extend_area_map() - and call it directly from pcpu_alloc() such that pcpu_alloc_area() is guaranteed to have enough area map slots on invocation. With this change, pcpu_alloc_area() does only area allocation and the only failure mode is when the chunk doens't have enough room, so there's no need to distinguish it from memory allocation failures. Make it return -1 on such cases instead of hacky -ENOSPC. Signed-off-by: Tejun Heo <tj@kernel.org>
| * | | percpu: replace pcpu_realloc() with pcpu_mem_alloc() and pcpu_mem_free()Tejun Heo2009-03-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: code reorganization for later changes With static map handling moved to pcpu_split_block(), pcpu_realloc() only clutters the code and it's also unsuitable for scheduled locking changes. Implement and use pcpu_mem_alloc/free() instead. Signed-off-by: Tejun Heo <tj@kernel.org>
| * | | percpu, module: implement reserved allocation and use it for module percpu ↵Tejun Heo2009-03-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | variables Impact: add reserved allocation functionality and use it for module percpu variables This patch implements reserved allocation from the first chunk. When setting up the first chunk, arch can ask to set aside certain number of bytes right after the core static area which is available only through a separate reserved allocator. This will be used primarily for module static percpu variables on architectures with limited relocation range to ensure that the module perpcu symbols are inside the relocatable range. If reserved area is requested, the first chunk becomes reserved and isn't available for regular allocation. If the first chunk also includes piggy-back dynamic allocation area, a separate chunk mapping the same region is created to serve dynamic allocation. The first one is called static first chunk and the second dynamic first chunk. Although they share the page map, their different area map initializations guarantee they serve disjoint areas according to their purposes. If arch doesn't setup reserved area, reserved allocation is handled like any other allocation. Signed-off-by: Tejun Heo <tj@kernel.org>
| * | | percpu: add an indirection ptr for chunk page map accessTejun Heo2009-03-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: allow sharing page map, no functional difference yet Make chunk->page access indirect by adding a pointer and renaming the actual array to page_ar. This will be used by future changes. Signed-off-by: Tejun Heo <tj@kernel.org>
| * | | percpu: use negative for auto for pcpu_setup_first_chunk() argumentsTejun Heo2009-03-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: argument semantic cleanup In pcpu_setup_first_chunk(), zero @unit_size and @dyn_size meant auto-sizing. It's okay for @unit_size as 0 doesn't make sense but 0 dynamic reserve size is valid. Alos, if arch @dyn_size is calculated from other parameters, it might end up passing in 0 @dyn_size and malfunction when the size is automatically adjusted. This patch makes both @unit_size and @dyn_size ssize_t and use -1 for auto sizing. Signed-off-by: Tejun Heo <tj@kernel.org>
| * | | percpu: improve first chunk initial area map handlingTejun Heo2009-03-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: no functional change When the first chunk is created, its initial area map is not allocated because kmalloc isn't online yet. The map is allocated and initialized on the first allocation request on the chunk. This works fine but the scattering of initialization logic between the init function and allocation path is a bit confusing. This patch makes the first chunk initialize and use minimal statically allocated map from pcpu_setpu_first_chunk(). The map resizing path still needs to handle this specially but it's more straight-forward and gives more latitude to the init path. This will ease future changes. Signed-off-by: Tejun Heo <tj@kernel.org>
| * | | percpu: cosmetic renames in pcpu_setup_first_chunk()Tejun Heo2009-03-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: cosmetic, preparation for future changes Make the following renames in pcpur_setup_first_chunk() in preparation for future changes. * s/free_size/dyn_size/ * s/static_vm/first_vm/ * s/static_chunk/schunk/ Signed-off-by: Tejun Heo <tj@kernel.org>
| * | | Merge branch 'x86/core' into core/percpuIngo Molnar2009-03-03
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| | *-------. | | Merge branches 'x86/apic', 'x86/cpu', 'x86/fixmap', 'x86/mm', 'x86/sched', ↵Ingo Molnar2009-03-03
| | |\ \ \ \ \| | | | | | | | | | | | | | | | | | | | | | | | | | | | | 'x86/setup-lzma', 'x86/signal' and 'x86/urgent' into x86/core
| | | | | * | | | Merge branch 'x86/urgent' into x86/patIngo Molnar2009-03-01
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| | | | * | | | x86, mm: dont use non-temporal stores in pagecache accessesIngo Molnar2009-03-02
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: standardize IO on cached ops On modern CPUs it is almost always a bad idea to use non-temporal stores, as the regression in this commit has shown it: 30d697f: x86: fix performance regression in write() syscall The kernel simply has no good information about whether using non-temporal stores is a good idea or not - and trying to add heuristics only increases complexity and inserts fragility. The regression on cached write()s took very long to be found - over two years. So dont take any chances and let the hardware decide how it makes use of its caches. The only exception is drivers/gpu/drm/i915/i915_gem.c: there were we are absolutely sure that another entity (the GPU) will pick up the dirty data immediately and that the CPU will not touch that data before the GPU will. Also, keep the _nocache() primitives to make it easier for people to experiment with these details. There may be more clear-cut cases where non-cached copies can be used, outside of filemap.c. Cc: Salman Qazi <sqazi@google.com> Cc: Nick Piggin <npiggin@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
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| | | *-. \ \ \ \ Merge branches 'x86/paravirt', 'x86/pat', 'x86/setup-v2', 'x86/subarch', ↵Ingo Molnar2009-02-13
| | | |\ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 'x86/uaccess' and 'x86/urgent' into x86/core
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| | *-. \ \ \ \ \ \ \ Merge branches 'x86/apic', 'x86/defconfig', 'x86/memtest', 'x86/mm' and ↵Ingo Molnar2009-02-26
| | |\ \ \ \ \ \ \ \ \ | | | | | |_|_|/ / / / | | | | |/| | | | | | | | | | | | | | | | | 'linus' into x86/core
| | | | * | | | | | | x86: make vmap yell louder when it is used under irqs_disabled()Peter Zijlstra2009-02-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Ingo Molnar <mingo@elte.hu>
| | | | * | | | | | | x86, mm: pass in 'total' to __copy_from_user_*nocache()Ingo Molnar2009-02-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: cleanup, enable future change Add a 'total bytes copied' parameter to __copy_from_user_*nocache(), and update all the callsites. The parameter is not used yet - architecture code can use it to more intelligently decide whether the copy should be cached or non-temporal. Cc: Salman Qazi <sqazi@google.com> Cc: Nick Piggin <npiggin@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | | | | | | | bootmem, x86: further fixes for arch-specific bootmem wrappingTejun Heo2009-03-01
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: fix new breakages introduced by previous fix Commit c132937556f56ee4b831ef4b23f1846e05fde102 tried to clean up bootmem arch wrapper but it wasn't quite correct. Before the commit, the followings were broken. * Low level interface functions prefixed with __ ignored arch preference. * reserve_bootmem(...) can't be mapped into reserve_bootmem_node(NODE_DATA(0)->bdata, ...) because the node is not preference here. The region specified MUST fall into the specified region; otherwise, it will panic. After the commit, * If allocation fails for the arch preferred node, it should fallback to whatever is available. Instead, it simply failed allocation. There are too many internal details to allow generic wrapping and still keep things simple for archs. Plus, all that arch wants is a way to prefer certain node over another. This patch drops the generic wrapping around alloc_bootmem_core() and add alloc_bootmem_core() instead. If necessary, arch can define bootmem_arch_referred_node() macro or function which takes all allocation information and returns the preferred node. bootmem generic code will always try the preferred node first and then fallback to other nodes as usual. Breakages noted and changes reviewed by Johannes Weiner. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Johannes Weiner <hannes@cmpxchg.org>
| * | | | | | | | | | percpu: kill compile warning in pcpu_populate_chunk()Tejun Heo2009-03-01
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: remove compile warning Mark local variable map_end in pcpu_populate_chunk() with uninitialized_var(). The variable is always used in tandem with map_start and guaranteed to be initialized before use but gcc doesn't understand that. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Ingo Molnar <mingo@elte.hu>
| * | | | | | | | | | Merge branch 'tj-percpu' of ↵Ingo Molnar2009-02-24
| |\ \ \ \ \ \ \ \ \ \ | | |/ / / / / / / / / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tj/misc into core/percpu Conflicts: arch/x86/include/asm/pgtable.h
| | * | | | | | | | | percpu: add __read_mostly to variables which are mostly read onlyTejun Heo2009-02-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Most global variables in percpu allocator are initialized during boot and read only from that point on. Add __read_mostly as per Rusty's suggestion. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au>
| | * | | | | | | | | percpu: give more latitude to arch specific first chunk initializationTejun Heo2009-02-23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: more latitude for first percpu chunk allocation The first percpu chunk serves the kernel static percpu area and may or may not contain extra room for further dynamic allocation. Initialization of the first chunk needs to be done before normal memory allocation service is up, so it has its own init path - pcpu_setup_static(). It seems archs need more latitude while initializing the first chunk for example to take advantage of large page mapping. This patch makes the following changes to allow this. * Define PERCPU_DYNAMIC_RESERVE to give arch hint about how much space to reserve in the first chunk for further dynamic allocation. * Rename pcpu_setup_static() to pcpu_setup_first_chunk(). * Make pcpu_setup_first_chunk() much more flexible by fetching page pointer by callback and adding optional @unit_size, @free_size and @base_addr arguments which allow archs to selectively part of chunk initialization to their likings. Signed-off-by: Tejun Heo <tj@kernel.org>
| | * | | | | | | | | percpu: remove unit_size power-of-2 restrictionTejun Heo2009-02-23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: allow unit_size to be arbitrary multiple of PAGE_SIZE In dynamic percpu allocator, there is no reason the unit size should be power of two. Remove the restriction. As non-power-of-two unit size means that empty chunks fall into the same slot index as lightly occupied chunks which is bad for reclaming. Reserve an extra slot for empty chunks. Signed-off-by: Tejun Heo <tj@kernel.org>
| | * | | | | | | | | vmalloc: add @align to vm_area_register_early()Tejun Heo2009-02-23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: allow larger alignment for early vmalloc area allocation Some early vmalloc users might want larger alignment, for example, for custom large page mapping. Add @align to vm_area_register_early(). While at it, drop docbook comment on non-existent @size. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
| | * | | | | | | | | bootmem: clean up arch-specific bootmem wrappingTejun Heo2009-02-23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: cleaner and consistent bootmem wrapping By setting CONFIG_HAVE_ARCH_BOOTMEM_NODE, archs can define arch-specific wrappers for bootmem allocation. However, this is done a bit strangely in that only the high level convenience macros can be changed while lower level, but still exported, interface functions can't be wrapped. This not only is messy but also leads to strange situation where alloc_bootmem() does what the arch wants it to do but the equivalent __alloc_bootmem() call doesn't although they should be able to be used interchangeably. This patch updates bootmem such that archs can override / wrap the backend function - alloc_bootmem_core() instead of the highlevel interface functions to allow simpler and consistent wrapping. Also, HAVE_ARCH_BOOTMEM_NODE is renamed to HAVE_ARCH_BOOTMEM. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Johannes Weiner <hannes@saeurebad.de>
| | * | | | | | | | | percpu: fix pcpu_chunk_struct_sizeTejun Heo2009-02-23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: fix short allocation leading to memory corruption While dropping rvalue wrapping macros around global parameters, pcpu_chunk_struct_size was set incorrectly resulting in shorter page pointer array. Fix it. Signed-off-by: Tejun Heo <tj@kernel.org>
| | * | | | | | | | | percpu: clean up size usageTejun Heo2009-02-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Andrew was concerned about the unit of variables named or have suffix size. Every usage in percpu allocator is in bytes but make it super clear by adding comments. While at it, make pcpu_depopulate_chunk() take int @off and @size like everyone else. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org>
| | * | | | | | | | | percpu: implement new dynamic percpu allocatorTejun Heo2009-02-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: new scalable dynamic percpu allocator which allows dynamic percpu areas to be accessed the same way as static ones Implement scalable dynamic percpu allocator which can be used for both static and dynamic percpu areas. This will allow static and dynamic areas to share faster direct access methods. This feature is optional and enabled only when CONFIG_HAVE_DYNAMIC_PER_CPU_AREA is defined by arch. Please read comment on top of mm/percpu.c for details. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org>
| | * | | | | | | | | vmalloc: add un/map_kernel_range_noflush()Tejun Heo2009-02-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: two more public map/unmap functions Implement map_kernel_range_noflush() and unmap_kernel_range_noflush(). These functions respectively map and unmap address range in kernel VM area but doesn't do any vcache or tlb flushing. These will be used by new percpu allocator. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Nick Piggin <nickpiggin@yahoo.com.au>
| | * | | | | | | | | vmalloc: implement vm_area_register_early()Tejun Heo2009-02-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: allow multiple early vm areas There are places where kernel VM area needs to be allocated before vmalloc is initialized. This is done by allocating static vm_struct, initializing several fields and linking it to vmlist and later vmalloc initialization picking up these from vmlist. This is currently done manually and if there's more than one such areas, there's no defined way to arbitrate who gets which address. This patch implements vm_area_register_early(), which takes vm_area struct with flags and size initialized, assigns address to it and puts it on the vmlist. This way, multiple early vm areas can determine which addresses they should use. The only current user - alpha mm init - is converted to use it. Signed-off-by: Tejun Heo <tj@kernel.org>
| | * | | | | | | | | percpu: kill percpu_alloc() and friendsTejun Heo2009-02-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: kill unused functions percpu_alloc() and its friends never saw much action. It was supposed to replace the cpu-mask unaware __alloc_percpu() but it never happened and in fact __percpu_alloc_mask() itself never really grew proper up/down handling interface either (no exported interface for populate/depopulate). percpu allocation is about to go through major reimplementation and there's no reason to carry this unused interface around. Replace it with __alloc_percpu() and free_percpu(). Signed-off-by: Tejun Heo <tj@kernel.org>
| | * | | | | | | | | vmalloc: call flush_cache_vunmap() from unmap_kernel_range()Tejun Heo2009-02-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: proper vcache flush on unmap_kernel_range() flush_cache_vunmap() should be called before pages are unmapped. Add a call to it in unmap_kernel_range(). Signed-off-by: Tejun Heo <tj@kernel.org>
* | | | | | | | | | | Merge branch 'for-linus' of ↵Linus Torvalds2009-03-26
|\ \ \ \ \ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6: slob: fix lockup in slob_free() slub: use get_track() slub: rename calculate_min_partial() to set_min_partial() slub: add min_partial sysfs tunable slub: move min_partial to struct kmem_cache SLUB: Fix default slab order for big object sizes SLUB: Do not pass 8k objects through to the page allocator SLUB: Introduce and use SLUB_MAX_SIZE and SLUB_PAGE_SHIFT constants slob: clean up the code SLUB: Use ->objsize from struct kmem_cache_cpu in slab_free()
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| *-------. \ \ \ \ \ \ \ \ \ \ Merge branches 'topic/slob/cleanups', 'topic/slob/fixes', 'topic/slub/core', ↵Pekka Enberg2009-03-24
| |\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ | | |_|_|_|_|_|_|_|_|_|_|_|_|_|/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 'topic/slub/cleanups' and 'topic/slub/perf' into for-linus
| | | | | | * | | | | | | | | | SLUB: Fix default slab order for big object sizesZhang Yanmin2009-02-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The default order of kmalloc-8192 on 2*4 stoakley is an issue of calculate_order. slab_size order name ------------------------------------------------- 4096 3 sgpool-128 8192 2 kmalloc-8192 16384 3 kmalloc-16384 kmalloc-8192's default order is smaller than sgpool-128's. On 4*4 tigerton machine, a similiar issue appears on another kmem_cache. Function calculate_order uses 'min_objects /= 2;' to shrink. Plus size calculation/checking in slab_order, sometimes above issue appear. Below patch against 2.6.29-rc2 fixes it. I checked the default orders of all kmem_cache and they don't become smaller than before. So the patch wouldn't hurt performance. Signed-off-by Zhang Yanmin <yanmin.zhang@linux.intel.com> Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
| | | | | | * | | | | | | | | | SLUB: Introduce and use SLUB_MAX_SIZE and SLUB_PAGE_SHIFT constantsChristoph Lameter2009-02-20
| | | | | | | |_|/ / / / / / / | | | | | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As a preparational patch to bump up page allocator pass-through threshold, introduce two new constants SLUB_MAX_SIZE and SLUB_PAGE_SHIFT and convert mm/slub.c to use them. Reported-by: "Zhang, Yanmin" <yanmin_zhang@linux.intel.com> Tested-by: "Zhang, Yanmin" <yanmin_zhang@linux.intel.com> Signed-off-by: Christoph Lameter <cl@linux-foundation.org> Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
| | | | | * | | | | | | | | | slub: use get_track()Akinobu Mita2009-03-23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use get_track() in set_track() Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
| | | | | * | | | | | | | | | SLUB: Use ->objsize from struct kmem_cache_cpu in slab_free()Pekka Enberg2009-01-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There's no reason to use ->objsize from struct kmem_cache in slab_free() for the SLAB_DEBUG_OBJECTS case. All it does is generate extra cache pressure as we try very hard not to touch struct kmem_cache in the fast-path. Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
| | | | * | | | | | | | | | | slub: rename calculate_min_partial() to set_min_partial()David Rientjes2009-02-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As suggested by Christoph Lameter, rename calculate_min_partial() to set_min_partial() as the function doesn't really do any calculations. Cc: Christoph Lameter <cl@linux-foundation.org> Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
| | | | * | | | | | | | | | | slub: add min_partial sysfs tunableDavid Rientjes2009-02-23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now that a cache's min_partial has been moved to struct kmem_cache, it's possible to easily tune it from userspace by adding a sysfs attribute. It may not be desirable to keep a large number of partial slabs around if a cache is used infrequently and memory, especially when constrained by a cgroup, is scarce. It's better to allow userspace to set the minimum policy per cache instead of relying explicitly on kmem_cache_shrink(). The memory savings from simply moving min_partial from struct kmem_cache_node to struct kmem_cache is obviously not significant (unless maybe you're from SGI or something), at the largest it's # allocated caches * (MAX_NUMNODES - 1) * sizeof(unsigned long) The true savings occurs when userspace reduces the number of partial slabs that would otherwise be wasted, especially on machines with a large number of nodes (ia64 with CONFIG_NODES_SHIFT at 10 for default?). As well as the kernel estimates ideal values for n->min_partial and ensures it's within a sane range, userspace has no other input other than writing to /sys/kernel/slab/cache/shrink. There simply isn't any better heuristic to add when calculating the partial values for a better estimate that works for all possible caches. And since it's currently a static value, the user really has no way of reclaiming that wasted space, which can be significant when constrained by a cgroup (either cpusets or, later, memory controller slab limits) without shrinking it entirely. This also allows the user to specify that increased fragmentation and more partial slabs are actually desired to avoid the cost of allocating new slabs at runtime for specific caches. There's also no reason why this should be a per-struct kmem_cache_node value in the first place. You could argue that a machine would have such node size asymmetries that it should be specified on a per-node basis, but we know nobody is doing that right now since it's a purely static value at the moment and there's no convenient way to tune that via slub's sysfs interface. Cc: Christoph Lameter <cl@linux-foundation.org> Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
| | | | * | | | | | | | | | | slub: move min_partial to struct kmem_cacheDavid Rientjes2009-02-23
| | | | | |/ / / / / / / / / | | | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Although it allows for better cacheline use, it is unnecessary to save a copy of the cache's min_partial value in each kmem_cache_node. Cc: Christoph Lameter <cl@linux-foundation.org> Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>