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* mm: optimize compound_head() by avoiding a shared page flagChristoph Lameter2007-05-072-20/+28
| | | | | | | | | | The patch adds PageTail(page) and PageHead(page) to check if a page is the head or the tail of a compound page. This is done by masking the two bits describing the state of a compound page and then comparing them. So one comparision and a branch instead of two bit checks and two branches. Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Make page->private usable in compound pagesChristoph Lameter2007-05-072-5/+42
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If we add a new flag so that we can distinguish between the first page and the tail pages then we can avoid to use page->private in the first page. page->private == page for the first page, so there is no real information in there. Freeing up page->private makes the use of compound pages more transparent. They become more usable like real pages. Right now we have to be careful f.e. if we are going beyond PAGE_SIZE allocations in the slab on i386 because we can then no longer use the private field. This is one of the issues that cause us not to support debugging for page size slabs in SLAB. Having page->private available for SLUB would allow more meta information in the page struct. I can probably avoid the 16 bit ints that I have in there right now. Also if page->private is available then a compound page may be equipped with buffer heads. This may free up the way for filesystems to support larger blocks than page size. We add PageTail as an alias of PageReclaim. Compound pages cannot currently be reclaimed. Because of the alias one needs to check PageCompound first. The RFC for the this approach was discussed at http://marc.info/?t=117574302800001&r=1&w=2 [nacc@us.ibm.com: fix hugetlbfs] Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* SLUB: allocate smallest object size if the user asks for 0 bytesChristoph Lameter2007-05-071-2/+6
| | | | | | | | | | | | | | Makes SLUB behave like SLAB in this area to avoid issues.... Throw a stack dump to alert people. At some point the behavior should be switched back. NULL is no memory as far as I can tell and if the use asked for 0 bytes then he need to get no memory. Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* SLUB coreChristoph Lameter2007-05-074-6/+229
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is a new slab allocator which was motivated by the complexity of the existing code in mm/slab.c. It attempts to address a variety of concerns with the existing implementation. A. Management of object queues A particular concern was the complex management of the numerous object queues in SLAB. SLUB has no such queues. Instead we dedicate a slab for each allocating CPU and use objects from a slab directly instead of queueing them up. B. Storage overhead of object queues SLAB Object queues exist per node, per CPU. The alien cache queue even has a queue array that contain a queue for each processor on each node. For very large systems the number of queues and the number of objects that may be caught in those queues grows exponentially. On our systems with 1k nodes / processors we have several gigabytes just tied up for storing references to objects for those queues This does not include the objects that could be on those queues. One fears that the whole memory of the machine could one day be consumed by those queues. C. SLAB meta data overhead SLAB has overhead at the beginning of each slab. This means that data cannot be naturally aligned at the beginning of a slab block. SLUB keeps all meta data in the corresponding page_struct. Objects can be naturally aligned in the slab. F.e. a 128 byte object will be aligned at 128 byte boundaries and can fit tightly into a 4k page with no bytes left over. SLAB cannot do this. D. SLAB has a complex cache reaper SLUB does not need a cache reaper for UP systems. On SMP systems the per CPU slab may be pushed back into partial list but that operation is simple and does not require an iteration over a list of objects. SLAB expires per CPU, shared and alien object queues during cache reaping which may cause strange hold offs. E. SLAB has complex NUMA policy layer support SLUB pushes NUMA policy handling into the page allocator. This means that allocation is coarser (SLUB does interleave on a page level) but that situation was also present before 2.6.13. SLABs application of policies to individual slab objects allocated in SLAB is certainly a performance concern due to the frequent references to memory policies which may lead a sequence of objects to come from one node after another. SLUB will get a slab full of objects from one node and then will switch to the next. F. Reduction of the size of partial slab lists SLAB has per node partial lists. This means that over time a large number of partial slabs may accumulate on those lists. These can only be reused if allocator occur on specific nodes. SLUB has a global pool of partial slabs and will consume slabs from that pool to decrease fragmentation. G. Tunables SLAB has sophisticated tuning abilities for each slab cache. One can manipulate the queue sizes in detail. However, filling the queues still requires the uses of the spin lock to check out slabs. SLUB has a global parameter (min_slab_order) for tuning. Increasing the minimum slab order can decrease the locking overhead. The bigger the slab order the less motions of pages between per CPU and partial lists occur and the better SLUB will be scaling. G. Slab merging We often have slab caches with similar parameters. SLUB detects those on boot up and merges them into the corresponding general caches. This leads to more effective memory use. About 50% of all caches can be eliminated through slab merging. This will also decrease slab fragmentation because partial allocated slabs can be filled up again. Slab merging can be switched off by specifying slub_nomerge on boot up. Note that merging can expose heretofore unknown bugs in the kernel because corrupted objects may now be placed differently and corrupt differing neighboring objects. Enable sanity checks to find those. H. Diagnostics The current slab diagnostics are difficult to use and require a recompilation of the kernel. SLUB contains debugging code that is always available (but is kept out of the hot code paths). SLUB diagnostics can be enabled via the "slab_debug" option. Parameters can be specified to select a single or a group of slab caches for diagnostics. This means that the system is running with the usual performance and it is much more likely that race conditions can be reproduced. I. Resiliency If basic sanity checks are on then SLUB is capable of detecting common error conditions and recover as best as possible to allow the system to continue. J. Tracing Tracing can be enabled via the slab_debug=T,<slabcache> option during boot. SLUB will then protocol all actions on that slabcache and dump the object contents on free. K. On demand DMA cache creation. Generally DMA caches are not needed. If a kmalloc is used with __GFP_DMA then just create this single slabcache that is needed. For systems that have no ZONE_DMA requirement the support is completely eliminated. L. Performance increase Some benchmarks have shown speed improvements on kernbench in the range of 5-10%. The locking overhead of slub is based on the underlying base allocation size. If we can reliably allocate larger order pages then it is possible to increase slub performance much further. The anti-fragmentation patches may enable further performance increases. Tested on: i386 UP + SMP, x86_64 UP + SMP + NUMA emulation, IA64 NUMA + Simulator SLUB Boot options slub_nomerge Disable merging of slabs slub_min_order=x Require a minimum order for slab caches. This increases the managed chunk size and therefore reduces meta data and locking overhead. slub_min_objects=x Mininum objects per slab. Default is 8. slub_max_order=x Avoid generating slabs larger than order specified. slub_debug Enable all diagnostics for all caches slub_debug=<options> Enable selective options for all caches slub_debug=<o>,<cache> Enable selective options for a certain set of caches Available Debug options F Double Free checking, sanity and resiliency R Red zoning P Object / padding poisoning U Track last free / alloc T Trace all allocs / frees (only use for individual slabs). To use SLUB: Apply this patch and then select SLUB as the default slab allocator. [hugh@veritas.com: fix an oops-causing locking error] [akpm@linux-foundation.org: various stupid cleanups and small fixes] Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Hugh Dickins <hugh@veritas.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* readahead: code cleanupJan Kara2007-05-071-2/+2
| | | | | | | | | | | | | | Rename file_ra_state.prev_page to prev_index and file_ra_state.offset to prev_offset. Also update of prev_index in do_generic_mapping_read() is now moved close to the update of prev_offset. [wfg@mail.ustc.edu.cn: fix it] Signed-off-by: Jan Kara <jack@suse.cz> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Cc: WU Fengguang <wfg@mail.ustc.edu.cn> Signed-off-by: Fengguang Wu <wfg@mail.ustc.edu.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* readahead: improve heuristic detecting sequential readsJan Kara2007-05-071-0/+1
| | | | | | | | | | | | | | Introduce ra.offset and store in it an offset where the previous read ended. This way we can detect whether reads are really sequential (and thus we should not mark the page as accessed repeatedly) or whether they are random and just happen to be in the same page (and the page should really be marked accessed again). Signed-off-by: Jan Kara <jack@suse.cz> Acked-by: Nick Piggin <nickpiggin@yahoo.com.au> Cc: WU Fengguang <wfg@mail.ustc.edu.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* smaps: add clear_refs file to clear referenceDavid Rientjes2007-05-071-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Adds /proc/pid/clear_refs. When any non-zero number is written to this file, pte_mkold() and ClearPageReferenced() is called for each pte and its corresponding page, respectively, in that task's VMAs. This file is only writable by the user who owns the task. It is now possible to measure _approximately_ how much memory a task is using by clearing the reference bits with echo 1 > /proc/pid/clear_refs and checking the reference count for each VMA from the /proc/pid/smaps output at a measured time interval. For example, to observe the approximate change in memory footprint for a task, write a script that clears the references (echo 1 > /proc/pid/clear_refs), sleeps, and then greps for Pgs_Referenced and extracts the size in kB. Add the sizes for each VMA together for the total referenced footprint. Moments later, repeat the process and observe the difference. For example, using an efficient Mozilla: accumulated time referenced memory ---------------- ----------------- 0 s 408 kB 1 s 408 kB 2 s 556 kB 3 s 1028 kB 4 s 872 kB 5 s 1956 kB 6 s 416 kB 7 s 1560 kB 8 s 2336 kB 9 s 1044 kB 10 s 416 kB This is a valuable tool to get an approximate measurement of the memory footprint for a task. Cc: Hugh Dickins <hugh@veritas.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Christoph Lameter <clameter@sgi.com> Signed-off-by: David Rientjes <rientjes@google.com> [akpm@linux-foundation.org: build fixes] [mpm@selenic.com: rename for_each_pmd] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Add unitialized_var() macro for suppressing gcc warningsBorislav Petkov2007-05-073-0/+14
| | | | | | | | | | | | | | | | | | | | | | | | | Introduce a macro for suppressing gcc from generating a warning about a probable uninitialized state of a variable. Example: - spinlock_t *ptl; + spinlock_t *uninitialized_var(ptl); Not a happy solution, but those warnings are obnoxious. - Using the usual pointlessly-set-it-to-zero approach wastes several bytes of text. - Using a macro means we can (hopefully) do something else if gcc changes cause the `x = x' hack to stop working - Using a macro means that people who are worried about hiding true bugs can easily turn it off. Signed-off-by: Borislav Petkov <bbpetkov@yahoo.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* add pfn_valid_within helper for sub-MAX_ORDER hole detectionAndy Whitcroft2007-05-071-0/+12
| | | | | | | | | | | | | | | | | | | Generally we work under the assumption that memory the mem_map array is contigious and valid out to MAX_ORDER_NR_PAGES block of pages, ie. that if we have validated any page within this MAX_ORDER_NR_PAGES block we need not check any other. This is not true when CONFIG_HOLES_IN_ZONE is set and we must check each and every reference we make from a pfn. Add a pfn_valid_within() helper which should be used when scanning pages within a MAX_ORDER_NR_PAGES block when we have already checked the validility of the block normally with pfn_valid(). This can then be optimised away when we do not have holes within a MAX_ORDER_NR_PAGES block of pages. Signed-off-by: Andy Whitcroft <apw@shadowen.org> Acked-by: Mel Gorman <mel@csn.ul.ie> Acked-by: Bob Picco <bob.picco@hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/slab.c: proper prototypesAdrian Bunk2007-05-071-0/+3
| | | | | | | | Add proper prototypes in include/linux/slab.h. Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: make read_cache_page synchronousNick Piggin2007-05-071-0/+11
| | | | | | | | | | | | | | | | Ensure pages are uptodate after returning from read_cache_page, which allows us to cut out most of the filesystem-internal PageUptodate calls. I didn't have a great look down the call chains, but this appears to fixes 7 possible use-before uptodate in hfs, 2 in hfsplus, 1 in jfs, a few in ecryptfs, 1 in jffs2, and a possible cleared data overwritten with readpage in block2mtd. All depending on whether the filler is async and/or can return with a !uptodate page. Signed-off-by: Nick Piggin <npiggin@suse.de> Cc: Hugh Dickins <hugh@veritas.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: remove gcc workaroundNick Piggin2007-05-071-0/+18
| | | | | | | | | | | | Minimum gcc version is 3.2 now. However, with likely profiling, even modern gcc versions cannot always eliminate the call. Replace the placeholder functions with the more conventional empty static inlines, which should be optimal for everyone. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* proper prototype for hugetlb_get_unmapped_area()Adrian Bunk2007-05-071-0/+6
| | | | | | | | | | Add a proper prototype for hugetlb_get_unmapped_area() in include/linux/hugetlb.h. Signed-off-by: Adrian Bunk <bunk@stusta.de> Acked-by: William Irwin <wli@holomorphy.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Add apply_to_page_range() which applies a function to a pte rangeJeremy Fitzhardinge2007-05-071-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | Add a new mm function apply_to_page_range() which applies a given function to every pte in a given virtual address range in a given mm structure. This is a generic alternative to cut-and-pasting the Linux idiomatic pagetable walking code in every place that a sequence of PTEs must be accessed. Although this interface is intended to be useful in a wide range of situations, it is currently used specifically by several Xen subsystems, for example: to ensure that pagetables have been allocated for a virtual address range, and to construct batched special pagetable update requests to map I/O memory (in ioremap()). [akpm@linux-foundation.org: fix warning, unpleasantly] Signed-off-by: Ian Pratt <ian.pratt@xensource.com> Signed-off-by: Christian Limpach <Christian.Limpach@cl.cam.ac.uk> Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Cc: Christoph Lameter <clameter@sgi.com> Cc: Matt Mackall <mpm@waste.org> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* serial: define FIXED_PORT flag for serial_coreDavid Gibson2007-05-071-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | At present, the serial core always allows setserial in userspace to change the port address, irq and base clock of any serial port. That makes sense for legacy ISA ports, but not for (say) embedded ns16550 compatible serial ports at peculiar addresses. In these cases, the kernel code configuring the ports must know exactly where they are, and their clocking arrangements (which can be unusual on embedded boards). It doesn't make sense for userspace to change these settings. Therefore, this patch defines a UPF_FIXED_PORT flag for the uart_port structure. If this flag is set when the serial port is configured, any attempts to alter the port's type, io address, irq or base clock with setserial are ignored. In addition this patch uses the new flag for on-chip serial ports probed in arch/powerpc/kernel/legacy_serial.c, and for other hard-wired serial ports probed by drivers/serial/of_serial.c. Signed-off-by: David Gibson <dwg@au1.ibm.com> Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* RM9000 serial driverThomas Koeller2007-05-071-1/+3
| | | | | | | | | | | | | | Add support for the integrated serial ports of the MIPS RM9122 processor and its relatives. The patch also does some whitespace cleanup. [akpm@linux-foundation.org: cleanups] Signed-off-by: Thomas Koeller <thomas.koeller@baslerweb.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* serial driver PMC MSP71xxMarc St-Jean2007-05-072-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Serial driver patch for the PMC-Sierra MSP71xx devices. There are three different fixes: 1 Fix for DesignWare APB THRE errata: In brief, this is a non-standard 16550 in that the THRE interrupt will not re-assert itself simply by disabling and re-enabling the THRI bit in the IER, it is only re-enabled if a character is actually sent out. It appears that the "8250-uart-backup-timer.patch" in the "mm" tree also fixes it so we have dropped our initial workaround. This patch now needs to be applied on top of that "mm" patch. 2 Fix for Busy Detect on LCR write: The DesignWare APB UART has a feature which causes a new Busy Detect interrupt to be generated if it's busy when the LCR is written. This fix saves the value of the LCR and rewrites it after clearing the interrupt. 3 Workaround for interrupt/data concurrency issue: The SoC needs to ensure that writes that can cause interrupts to be cleared reach the UART before returning from the ISR. This fix reads a non-destructive register on the UART so the read transaction completion ensures the previously queued write transaction has also completed. Signed-off-by: Marc St-Jean <Marc_St-Jean@pmc-sierra.com> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* slab: introduce kreallocPekka Enberg2007-05-071-1/+2
| | | | | | | | | | | | | | | This introduce krealloc() that reallocates memory while keeping the contents unchanged. The allocator avoids reallocation if the new size fits the currently used cache. I also added a simple non-optimized version for mm/slob.c for compatibility. [akpm@linux-foundation.org: fix warnings] Acked-by: Josef Sipek <jsipek@fsl.cs.sunysb.edu> Acked-by: Matt Mackall <mpm@selenic.com> Acked-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuildLinus Torvalds2007-05-062-0/+5
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild: (38 commits) kconfig: fix mconf segmentation fault kbuild: enable use of code from a different dir kconfig: error out if recursive dependencies are found kbuild: scripts/basic/fixdep segfault on pathological string-o-death kconfig: correct minor typo in Kconfig warning message. kconfig: fix path to modules.txt in Kconfig help usr/Kconfig: fix typo kernel-doc: alphabetically-sorted entries in index.html of 'htmldocs' kbuild: be more explicit on missing .config file kbuild: clarify the creation of the LOCALVERSION_AUTO string. kbuild: propagate errors from find in scripts/gen_initramfs_list.sh kconfig: refer to qt3 if we cannot find qt libraries kbuild: handle compressed cpio initramfs-es kbuild: ignore section mismatch warning for references from .paravirtprobe to .init.text kbuild: remove stale comment in modpost.c kbuild/mkuboot.sh: allow spaces in CROSS_COMPILE kbuild: fix make mrproper for Documentation/DocBook/man kbuild: remove kconfig binaries during make mrproper kconfig/menuconfig: do not hardcode '.config' kbuild: override build timestamp & version ...
| * kbuild: remove dependency on input.h from file2aliasSam Ravnborg2007-05-022-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | Almost all definitions used by file2alias was already present in mod_devicetable.h. Added the last definition and killed the input.h usage. The errornous include was pointed out by: Jan Engelhardt <jengelh@linux01.gwdg.de> Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Cc: Jan Engelhardt <jengelh@linux01.gwdg.de> Cc: Deepak Saxena <dsaxena@plexity.net>
* | Merge branch 'for-linus' of ↵Linus Torvalds2007-05-063-38/+97
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/avi/kvm * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/avi/kvm: (66 commits) KVM: Remove unused 'instruction_length' KVM: Don't require explicit indication of completion of mmio or pio KVM: Remove extraneous guest entry on mmio read KVM: SVM: Only save/restore MSRs when needed KVM: fix an if() condition KVM: VMX: Add lazy FPU support for VT KVM: VMX: Properly shadow the CR0 register in the vcpu struct KVM: Don't complain about cpu erratum AA15 KVM: Lazy FPU support for SVM KVM: Allow passing 64-bit values to the emulated read/write API KVM: Per-vcpu statistics KVM: VMX: Avoid unnecessary vcpu_load()/vcpu_put() cycles KVM: MMU: Avoid heavy ASSERT at non debug mode. KVM: VMX: Only save/restore MSR_K6_STAR if necessary KVM: Fold drivers/kvm/kvm_vmx.h into drivers/kvm/vmx.c KVM: VMX: Don't switch 64-bit msrs for 32-bit guests KVM: VMX: Reduce unnecessary saving of host msrs KVM: Handle guest page faults when emulating mmio KVM: SVM: Report hardware exit reason to userspace instead of dmesg KVM: Retry sleeping allocation if atomic allocation fails ...
| * | KVM: Remove unused 'instruction_length'Avi Kivity2007-05-031-3/+2
| | | | | | | | | | | | | | | | | | | | | As we no longer emulate in userspace, this is meaningless. We don't compute it on SVM anyway. Signed-off-by: Avi Kivity <avi@qumranet.com>
| * | KVM: Don't require explicit indication of completion of mmio or pioAvi Kivity2007-05-031-3/+2
| | | | | | | | | | | | | | | | | | | | | | | | It is illegal not to return from a pio or mmio request without completing it, as mmio or pio is an atomic operation. Therefore, we can simplify the userspace interface by avoiding the completion indication. Signed-off-by: Avi Kivity <avi@qumranet.com>
| * | KVM: Add fpu get/set operationsAvi Kivity2007-05-031-0/+17
| | | | | | | | | | | | | | | | | | | | | These are really helpful when migrating an floating point app to another machine. Signed-off-by: Avi Kivity <avi@qumranet.com>
| * | KVM: Add physical memory aliasing featureAvi Kivity2007-05-031-1/+9
| | | | | | | | | | | | | | | | | | | | | | | | With this, we can specify that accesses to one physical memory range will be remapped to another. This is useful for the vga window at 0xa0000 which is used as a movable window into the (much larger) framebuffer. Signed-off-by: Avi Kivity <avi@qumranet.com>
| * | KVM: Avoid guest virtual addresses in string pio userspace interfaceAvi Kivity2007-05-031-9/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The current string pio interface communicates using guest virtual addresses, relying on userspace to translate addresses and to check permissions. This interface cannot fully support guest smp, as the check needs to take into account two pages at one in case an unaligned string transfer straddles a page boundary. Change the interface not to communicate guest addresses at all; instead use a buffer page (mmaped by userspace) and do transfers there. The kernel manages the virtual to physical translation and can perform the checks atomically by taking the appropriate locks. Signed-off-by: Avi Kivity <avi@qumranet.com>
| * | KVM: Allow kernel to select size of mmap() bufferAvi Kivity2007-05-031-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | This allows us to store offsets in the kernel/user kvm_run area, and be sure that userspace has them mapped. As offsets can be outside the kvm_run struct, userspace has no way of knowing how much to mmap. Signed-off-by: Avi Kivity <avi@qumranet.com>
| * | KVM: Add guest mode signal maskAvi Kivity2007-05-031-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | Allow a special signal mask to be used while executing in guest mode. This allows signals to be used to interrupt a vcpu without requiring signal delivery to a userspace handler, which is quite expensive. Userspace still receives -EINTR and can get the signal via sigwait(). Signed-off-by: Avi Kivity <avi@qumranet.com>
| * | KVM: Add a special exit reason when exiting due to an interruptAvi Kivity2007-05-031-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | This is redundant, as we also return -EINTR from the ioctl, but it allows us to examine the exit_reason field on resume without seeing old data. Signed-off-by: Avi Kivity <avi@qumranet.com>
| * | KVM: Fold kvm_run::exit_type into kvm_run::exit_reasonAvi Kivity2007-05-031-7/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, userspace is told about the nature of the last exit from the guest using two fields, exit_type and exit_reason, where exit_type has just two enumerations (and no need for more). So fold exit_type into exit_reason, reducing the complexity of determining what really happened. Signed-off-by: Avi Kivity <avi@qumranet.com>
| * | KVM: Allow userspace to process hypercalls which have no kernel handlerAvi Kivity2007-05-031-1/+9
| | | | | | | | | | | | | | | | | | This is useful for paravirtualized graphics devices, for example. Signed-off-by: Avi Kivity <avi@qumranet.com>
| * | KVM: Add method to check for backwards-compatible API extensionsAvi Kivity2007-05-031-0/+5
| | | | | | | | | | | | Signed-off-by: Avi Kivity <avi@qumranet.com>
| * | KVM: Renumber ioctlsAvi Kivity2007-05-031-17/+17
| | | | | | | | | | | | | | | | | | The recent changes have left the ioctl numbers in complete disarray. Signed-off-by: Avi Kivity <avi@qumranet.com>
| * | KVM: Remove minor wart from KVM_CREATE_VCPU ioctlAvi Kivity2007-05-031-1/+1
| | | | | | | | | | | | | | | | | | | | | That ioctl does not transfer any data, so it should be an _IO rather than an _IOW. Signed-off-by: Avi Kivity <avi@qumranet.com>
| * | KVM: Remove the 'emulated' field from the userspace interfaceAvi Kivity2007-05-031-2/+1
| | | | | | | | | | | | | | | | | | | | | We no longer emulate single instructions in userspace. Instead, we service mmio or pio requests. Signed-off-by: Avi Kivity <avi@qumranet.com>
| * | KVM: Handle cpuid in the kernel instead of punting to userspaceAvi Kivity2007-05-031-1/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | KVM used to handle cpuid by letting userspace decide what values to return to the guest. We now handle cpuid completely in the kernel. We still let userspace decide which values the guest will see by having userspace set up the value table beforehand (this is necessary to allow management software to set the cpu features to the least common denominator, so that live migration can work). The motivation for the change is that kvm kernel code can be impacted by cpuid features, for example the x86 emulator. Signed-off-by: Avi Kivity <avi@qumranet.com>
| * | KVM: Do not communicate to userspace through cpu registers during PIOAvi Kivity2007-05-031-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently when passing the a PIO emulation request to userspace, we rely on userspace updating %rax (on 'in' instructions) and %rsi/%rdi/%rcx (on string instructions). This (a) requires two extra ioctls for getting and setting the registers and (b) is unfriendly to non-x86 archs, when they get kvm ports. So fix by doing the register fixups in the kernel and passing to userspace only an abstract description of the PIO to be done. Signed-off-by: Avi Kivity <avi@qumranet.com>
| * | KVM: Use a shared page for kernel/user communication when runing a vcpuAvi Kivity2007-05-031-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | Instead of passing a 'struct kvm_run' back and forth between the kernel and userspace, allocate a page and allow the user to mmap() it. This reduces needless copying and makes the interface expandable by providing lots of free space. Signed-off-by: Avi Kivity <avi@qumranet.com>
| * | KVM: Export <linux/kvm.h>Avi Kivity2007-05-031-0/+1
| | | | | | | | | | | | | | | | | | | | | This allows users to actually build prgrams that use kvm without the entire source tree. Signed-off-by: Avi Kivity <avi@qumranet.com>
| * | KVM: Use own minor numberAvi Kivity2007-05-031-0/+1
| |/ | | | | | | | | | | Use the minor number (232) allocated to kvm by lanana. Signed-off-by: Avi Kivity <avi@qumranet.com>
* | Merge branch 'for-linus' of git://one.firstfloor.org/home/andi/git/linux-2.6Linus Torvalds2007-05-0510-22/+64
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * 'for-linus' of git://one.firstfloor.org/home/andi/git/linux-2.6: (231 commits) [PATCH] i386: Don't delete cpu_devs data to identify different x86 types in late_initcall [PATCH] i386: type may be unused [PATCH] i386: Some additional chipset register values validation. [PATCH] i386: Add missing !X86_PAE dependincy to the 2G/2G split. [PATCH] x86-64: Don't exclude asm-offsets.c in Documentation/dontdiff [PATCH] i386: avoid redundant preempt_disable in __unlazy_fpu [PATCH] i386: white space fixes in i387.h [PATCH] i386: Drop noisy e820 debugging printks [PATCH] x86-64: Fix allnoconfig error in genapic_flat.c [PATCH] x86-64: Shut up warnings for vfat compat ioctls on other file systems [PATCH] x86-64: Share identical video.S between i386 and x86-64 [PATCH] x86-64: Remove CONFIG_REORDER [PATCH] x86-64: Print type and size correctly for unknown compat ioctls [PATCH] i386: Remove copy_*_user BUG_ONs for (size < 0) [PATCH] i386: Little cleanups in smpboot.c [PATCH] x86-64: Don't enable NUMA for a single node in K8 NUMA scanning [PATCH] x86: Use RDTSCP for synchronous get_cycles if possible [PATCH] i386: Add X86_FEATURE_RDTSCP [PATCH] i386: Implement X86_FEATURE_SYNC_RDTSC on i386 [PATCH] i386: Implement alternative_io for i386 ... Fix up trivial conflict in include/linux/highmem.h manually. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | [PATCH] i386: Clean up ELF note generationJeremy Fitzhardinge2007-05-021-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Three cleanups: 1: ELF notes are never mapped, so there's no need to have any access flags in their phdr. 2: When generating them from asm, tell the assembler to use a SHT_NOTE section type. There doesn't seem to be a way to do this from C. 3: Use ANSI rather than traditional cpp behaviour to stringify the macro argument. Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by: Andi Kleen <ak@suse.de> Cc: Eric W. Biederman <ebiederm@xmission.com>
| * | [PATCH] i386: PARAVIRT: add kmap_atomic_pte for mapping highpte pagesJeremy Fitzhardinge2007-05-021-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Xen and VMI both have special requirements when mapping a highmem pte page into the kernel address space. These can be dealt with by adding a new kmap_atomic_pte() function for mapping highptes, and hooking it into the paravirt_ops infrastructure. Xen specifically wants to map the pte page RO, so this patch exposes a helper function, kmap_atomic_prot, which maps the page with the specified page protections. This also adds a kmap_flush_unused() function to clear out the cached kmap mappings. Xen needs this to clear out any potential stray RW mappings of pages which will become part of a pagetable. [ Zach - vmi.c will need some attention after this patch. It wasn't immediately obvious to me what needs to be done. ] Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by: Andi Kleen <ak@suse.de> Cc: Zachary Amsden <zach@vmware.com>
| * | [PATCH] i386: Relocate VDSO ELF headers to match mapped location with ↵Jeremy Fitzhardinge2007-05-021-0/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | COMPAT_VDSO Some versions of libc can't deal with a VDSO which doesn't have its ELF headers matching its mapped address. COMPAT_VDSO maps the VDSO at a specific system-wide fixed address. Previously this was all done at build time, on the grounds that the fixed VDSO address is always at the top of the address space. However, a hypervisor may reserve some of that address space, pushing the fixmap address down. This patch does the adjustment dynamically at runtime, depending on the runtime location of the VDSO fixmap. [ Patch has been through several hands: Jan Beulich wrote the orignal version; Zach reworked it, and Jeremy converted it to relocate phdrs as well as sections. ] Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by: Andi Kleen <ak@suse.de> Cc: Zachary Amsden <zach@vmware.com> Cc: "Jan Beulich" <JBeulich@novell.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Andi Kleen <ak@suse.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: Roland McGrath <roland@redhat.com>
| * | [PATCH] x86-64: Account for module percpu space separately from kernel percpuJeremy Fitzhardinge2007-05-021-1/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Rather than using a single constant PERCPU_ENOUGH_ROOM, compute it as the sum of kernel_percpu + PERCPU_MODULE_RESERVE. This is now common to all architectures; if an architecture wants to set PERCPU_ENOUGH_ROOM to something special, then it may do so (ia64 is the only one which does). Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by: Andi Kleen <ak@suse.de> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Andi Kleen <ak@suse.de>
| * | [PATCH] x86: tighten kernel image page access rightsJan Beulich2007-05-021-3/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On x86-64, kernel memory freed after init can be entirely unmapped instead of just getting 'poisoned' by overwriting with a debug pattern. On i386 and x86-64 (under CONFIG_DEBUG_RODATA), kernel text and bug table can also be write-protected. Compared to the first version, this one prevents re-creating deleted mappings in the kernel image range on x86-64, if those got removed previously. This, together with the original changes, prevents temporarily having inconsistent mappings when cacheability attributes are being changed on such pages (e.g. from AGP code). While on i386 such duplicate mappings don't exist, the same change is done there, too, both for consistency and because checking pte_present() before using various other pte_XXX functions is a requirement anyway. At once, i386 code gets adjusted to use pte_huge() instead of open coding this. AK: split out cpa() changes Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Andi Kleen <ak@suse.de>
| * | [PATCH] i386: Allow i386 crash kernels to handle x86_64 dumpsIan Campbell2007-05-021-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The specific case I am encountering is kdump under Xen with a 64 bit hypervisor and 32 bit kernel/userspace. The dump created is 64 bit due to the hypervisor but the dump kernel is 32 bit for maximum compatibility. It's possibly less likely to be useful in a purely native scenario but I see no reason to disallow it. [akpm@linux-foundation.org: build fix] Signed-off-by: Ian Campbell <ian.campbell@xensource.com> Signed-off-by: Andi Kleen <ak@suse.de> Acked-by: Vivek Goyal <vgoyal@in.ibm.com> Cc: Horms <horms@verge.net.au> Cc: Magnus Damm <magnus.damm@gmail.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Andi Kleen <ak@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| * | [PATCH] x86-64: Set HASHDIST_DEFAULT to 1 for x86_64 NUMARavikiran G Thirumalai2007-05-021-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Enable system hashtable memory to be distributed among nodes on x86_64 NUMA Forcing the kernel to use node interleaved vmalloc instead of bootmem for the system hashtable memory (alloc_large_system_hash) reduces the memory imbalance on node 0 by around 40MB on a 8 node x86_64 NUMA box: Before the following patch, on bootup of a 8 node box: Node 0 MemTotal: 3407488 kB Node 0 MemFree: 3206296 kB Node 0 MemUsed: 201192 kB Node 0 Active: 7012 kB Node 0 Inactive: 512 kB Node 0 Dirty: 0 kB Node 0 Writeback: 0 kB Node 0 FilePages: 1912 kB Node 0 Mapped: 420 kB Node 0 AnonPages: 5612 kB Node 0 PageTables: 468 kB Node 0 NFS_Unstable: 0 kB Node 0 Bounce: 0 kB Node 0 Slab: 5408 kB Node 0 SReclaimable: 644 kB Node 0 SUnreclaim: 4764 kB After the patch (or using hashdist=1 on the kernel command line): Node 0 MemTotal: 3407488 kB Node 0 MemFree: 3247608 kB Node 0 MemUsed: 159880 kB Node 0 Active: 3012 kB Node 0 Inactive: 616 kB Node 0 Dirty: 0 kB Node 0 Writeback: 0 kB Node 0 FilePages: 2424 kB Node 0 Mapped: 380 kB Node 0 AnonPages: 1200 kB Node 0 PageTables: 396 kB Node 0 NFS_Unstable: 0 kB Node 0 Bounce: 0 kB Node 0 Slab: 6304 kB Node 0 SReclaimable: 1596 kB Node 0 SUnreclaim: 4708 kB I guess it is a good idea to keep HASHDIST_DEFAULT "on" for x86_64 NUMA since x86_64 has no dearth of vmalloc space? Or maybe enable hash distribution for all 64bit NUMA arches? The following patch does it only for x86_64. I ran a HPC MPI benchmark -- 'Ansys wingsolid', which takes up quite a bit of memory and uses up tlb entries. This was on a 4 way, 2 socket Tyan AMD box (non vsmp), with 8G total memory (4G pernode). The results with and without hash distribution are: 1. Vanilla - runtime of 1188.000s 2. With hashdist=1 runtime of 1154.000s Oprofile output for the duration of run is: 1. Vanilla: PU: AMD64 processors, speed 2411.16 MHz (estimated) Counted L1_AND_L2_DTLB_MISSES events (L1 and L2 DTLB misses) with a unit mask of 0x00 (No unit mask) count 500 samples % app name symbol name 163054 6.5513 libansys1.so MultiFront::decompose(int, int, Elemset *, int *, int, int, int) 162061 6.5114 libansys3.so blockSaxpy6L_fd 162042 6.5107 libansys3.so blockInnerProduct6L_fd 156286 6.2794 libansys3.so maxb33_ 87879 3.5309 libansys1.so elmatrixmultpcg_ 84857 3.4095 libansys4.so saxpy_pcg 58637 2.3560 libansys4.so .st4560 46612 1.8728 libansys4.so .st4282 43043 1.7294 vmlinux-t copy_user_generic_string 41326 1.6604 libansys3.so blockSaxpyBackSolve6L_fd 41288 1.6589 libansys3.so blockInnerProductBackSolve6L_fd 2. With hashdist=1 CPU: AMD64 processors, speed 2411.13 MHz (estimated) Counted L1_AND_L2_DTLB_MISSES events (L1 and L2 DTLB misses) with a unit mask of 0x00 (No unit mask) count 500 samples % app name symbol name 162993 6.9814 libansys1.so MultiFront::decompose(int, int, Elemset *, int *, int, int, int) 160799 6.8874 libansys3.so blockInnerProduct6L_fd 160459 6.8729 libansys3.so blockSaxpy6L_fd 156018 6.6826 libansys3.so maxb33_ 84700 3.6279 libansys4.so saxpy_pcg 83434 3.5737 libansys1.so elmatrixmultpcg_ 58074 2.4875 libansys4.so .st4560 46000 1.9703 libansys4.so .st4282 41166 1.7632 libansys3.so blockSaxpyBackSolve6L_fd 41033 1.7575 libansys3.so blockInnerProductBackSolve6L_fd 35762 1.5318 libansys1.so inner_product_sub 35591 1.5245 libansys1.so inner_product_sub2 28259 1.2104 libansys4.so addVectors Signed-off-by: Pravin B. Shelar <pravin.shelar@calsoftinc.com> Signed-off-by: Ravikiran Thirumalai <kiran@scalex86.org> Signed-off-by: Shai Fultheim <shai@scalex86.org> Signed-off-by: Andi Kleen <ak@suse.de> Acked-by: Christoph Lameter <clameter@engr.sgi.com> Cc: Andi Kleen <ak@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| * | [PATCH] x86-64: fix x86_64-mm-sched-clock-shareAndrew Morton2007-05-021-3/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix for the following patch. Provide dummy cpufreq functions when CPUFREQ is not compiled in. Cc: Andi Kleen <ak@suse.de> Cc: Dave Jones <davej@codemonkey.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andi Kleen <ak@suse.de>
| * | [PATCH] i386: clean up mach_reboot_fixupsJeremy Fitzhardinge2007-05-021-10/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The reboot_fixups stuff seems to be a bit of a mess, specifically the header is in linux/ when its a purely i386-specific piece of code. I'm not sure why it has its config option; its only currently needed for "geode-gx1/cs5530a", so perhaps whatever config option controls that hardware should enable this? Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by: Andi Kleen <ak@suse.de>