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2012-12-06lib/Makefile: Fix oid_registry build dependencyTim Gardner
It is $(obj)/oid_registry.o that is dependent on $(obj)/oid_registry_data.c. The object file cannot be built until $(obj)/oid_registry_data.c has been generated. A periodic and hard to reproduce parallel build failure is due to this incorrect lib/Makefile dependency. The compile error is completely disingenuous. GEN lib/oid_registry_data.c Compiling 49 OIDs CC lib/oid_registry.o gcc: error: lib/oid_registry.c: No such file or directory gcc: fatal error: no input files compilation terminated. make[3]: *** [lib/oid_registry.o] Error 4 Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Akinobu Mita <akinobu.mita@gmail.com> Cc: Michel Lespinasse <walken@google.com> Cc: David Howells <dhowells@redhat.com> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Tim Gardner <tim.gardner@canonical.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-12-05ASN.1: Fix an indefinite length skip errorDavid Howells
Fix an error in asn1_find_indefinite_length() whereby small definite length elements of size 0x7f are incorrecly classified as non-small. Without this fix, an error will be given as the length of the length will be perceived as being very much greater than the maximum supported size. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-12-03treewide: Fix typos in various KconfigMasanari Iida
Correct spelling typo within various Kconfig. Signed-off-by: Masanari Iida <standby24x7@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2012-12-03Merge branch 'rcu/next' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu Conflicts: arch/x86/kernel/ptrace.c Pull the latest RCU tree from Paul E. McKenney: " The major features of this series are: 1. A first version of no-callbacks CPUs. This version prohibits offlining CPU 0, but only when enabled via CONFIG_RCU_NOCB_CPU=y. Relaxing this constraint is in progress, but not yet ready for prime time. These commits were posted to LKML at https://lkml.org/lkml/2012/10/30/724, and are at branch rcu/nocb. 2. Changes to SRCU that allows statically initialized srcu_struct structures. These commits were posted to LKML at https://lkml.org/lkml/2012/10/30/296, and are at branch rcu/srcu. 3. Restructuring of RCU's debugfs output. These commits were posted to LKML at https://lkml.org/lkml/2012/10/30/341, and are at branch rcu/tracing. 4. Additional CPU-hotplug/RCU improvements, posted to LKML at https://lkml.org/lkml/2012/10/30/327, and are at branch rcu/hotplug. Note that the commit eliminating __stop_machine() was judged to be too-high of risk, so is deferred to 3.9. 5. Changes to RCU's idle interface, most notably a new module parameter that redirects normal grace-period operations to their expedited equivalents. These were posted to LKML at https://lkml.org/lkml/2012/10/30/739, and are at branch rcu/idle. 6. Additional diagnostics for RCU's CPU stall warning facility, posted to LKML at https://lkml.org/lkml/2012/10/30/315, and are at branch rcu/stall. The most notable change reduces the default RCU CPU stall-warning time from 60 seconds to 21 seconds, so that it once again happens sooner than the softlockup timeout. 7. Documentation updates, which were posted to LKML at https://lkml.org/lkml/2012/10/30/280, and are at branch rcu/doc. A couple of late-breaking changes were posted at https://lkml.org/lkml/2012/11/16/634 and https://lkml.org/lkml/2012/11/16/547. 8. Miscellaneous fixes, which were posted to LKML at https://lkml.org/lkml/2012/10/30/309, along with a late-breaking change posted at Fri, 16 Nov 2012 11:26:25 -0800 with message-ID <20121116192625.GA447@linux.vnet.ibm.com>, but which lkml.org seems to have missed. These are at branch rcu/fixes. 9. Finally, a fix for an lockdep-RCU splat was posted to LKML at https://lkml.org/lkml/2012/11/7/486. This is at rcu/next. " Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-11-28lib: kobject_uevent is no longer dependant on CONFIG_HOTPLUGBill Pemberton
CONFIG_HOTPLUG is being removed so kobject_uevent needs to always be part of the library. Signed-off-by: Bill Pemberton <wfp5p@virginia.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-23MPI: Fix compilation on MIPS with GCC 4.4 and newerManuel Lauss
Since 4.4 GCC on MIPS no longer recognizes the "h" constraint, leading to this build failure: CC lib/mpi/generic_mpih-mul1.o lib/mpi/generic_mpih-mul1.c: In function 'mpihelp_mul_1': lib/mpi/generic_mpih-mul1.c:50:3: error: impossible constraint in 'asm' This patch updates MPI with the latest umul_ppm implementations for MIPS. Signed-off-by: Manuel Lauss <manuel.lauss@gmail.com> Cc: Linux-MIPS <linux-mips@linux-mips.org> Cc: Dmitry Kasatkin <dmitry.kasatkin@intel.com> Cc: James Morris <jmorris@namei.org> Patchwork: https://patchwork.linux-mips.org/patch/4612/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2012-11-17dma-debug: fix to not have dependency on get_dma_ops() interfaceShuah Khan
dma-debug depends on get_dma_ops() interface. Several architectures do not define dma_ops and get_dma_ops(). When dma debug interfaces are used on an architecture (e.g: c6x) that doesn't define get_dmap_ops(), compilation fails. Changing dma-debug to call dma_mapping_error() instead of defining its own that calls get_dma_ops(), such that the internal use of dma_mapping_error() doesn't interfere with the debug_dma_mapping_error() interface's mapping error checks. Moving dma_mapping_error() checks in check_unmap() under the dma debug entry not found is sufficient to fix the problem. Reference: https://lkml.org/lkml/2012/10/26/367 Signed-off-by: Shuah Khan <shuah.khan@hp.com> Reported-by: Mark Salter <msalter@redhat.com> Signed-off-by: Joerg Roedel <joro@8bytes.org>
2012-11-13rcu: Reduce default RCU CPU stall warning timeoutPaul E. McKenney
The RCU CPU stall warning timeout has defaulted to 60 seconds for some years, with almost no false positives. This commit therefore reduces the default to 21 seconds, slightly shorter than the new soft-lockup timeout. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2012-11-09Merge branch 'drbd-8.4_ed6' into for-3.8-drivers-drbd-8.4_ed6Philipp Reisner
2012-10-30swiotlb: Do not export swiotlb_bounce since there are no external consumersAlexander Duyck
Currently swiotlb is the only consumer for swiotlb_bounce. Since that is the case it doesn't make much sense to be exporting it so make it a static function only. In addition we can save a few more lines of code by making it so that it accepts the DMA address as a physical address instead of a virtual one. This is the last piece in essentially pushing all of the DMA address values to use physical addresses in swiotlb. In order to clarify things since we now have 2 physical addresses in use inside of swiotlb_bounce I am renaming phys to orig_addr, and dma_addr to tlb_addr. This way is should be clear that orig_addr is contained within io_orig_addr and tlb_addr is an address within the io_tlb_addr buffer. Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-10-30swiotlb: Use physical addresses instead of virtual in swiotlb_tbl_sync_singleAlexander Duyck
This change makes it so that the sync functionality also uses physical addresses. This helps to further reduce the use of virt_to_phys and phys_to_virt functions. In order to clarify things since we now have 2 physical addresses in use inside of swiotlb_tbl_sync_single I am renaming phys to orig_addr, and dma_addr to tlb_addr. This way is should be clear that orig_addr is contained within io_orig_addr and tlb_addr is an address within the io_tlb_addr buffer. Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-10-30swiotlb: Use physical addresses for swiotlb_tbl_unmap_singleAlexander Duyck
This change makes it so that the unmap functionality also uses physical addresses. This helps to further reduce the use of virt_to_phys and phys_to_virt functions. In order to clarify things since we now have 2 physical addresses in use inside of swiotlb_tbl_unmap_single I am renaming phys to orig_addr, and dma_addr to tlb_addr. This way is should be clear that orig_addr is contained within io_orig_addr and tlb_addr is an address within the io_tlb_addr buffer. Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-10-30swiotlb: Return physical addresses when calling swiotlb_tbl_map_singleAlexander Duyck
This change makes it so that swiotlb_tbl_map_single will return a physical address instead of a virtual address when called. The advantage to this once again is that we are avoiding a number of virt_to_phys and phys_to_virt translations by working with everything as a physical address. One change I had to make in order to support using physical addresses is that I could no longer trust 0 to be a invalid physical address on all platforms. So instead I made it so that ~0 is returned on error. This should never be a valid return value as it implies that only one byte would be available for use. In order to clarify things since we now have 2 physical addresses in use inside of swiotlb_tbl_map_single I am renaming phys to orig_addr, and dma_addr to tlb_addr. This way is should be clear that orig_addr is contained within io_orig_addr and tlb_addr is an address within the io_tlb_addr buffer. Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-10-30swiotlb: Make io_tlb_overflow_buffer a physical addressAlexander Duyck
This change makes it so that we can avoid virt_to_phys overhead when using the io_tlb_overflow_buffer. My original plan was to completely remove the value and replace it with a constant but I had seen that there were recent patches that stated this couldn't be done until all device drivers that depended on that functionality be updated. Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-10-30swiotlb: Make io_tlb_start a physical address instead of a virtual oneAlexander Duyck
This change replaces all references to the virtual address for io_tlb_start with references to the physical address io_tlb_end. The main advantage of replacing the virtual address with a physical address is that we can avoid having to do multiple translations from the virtual address to the physical one needed for testing an existing DMA address. Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-10-30swiotlb: Make io_tlb_end a physical address instead of a virtual oneAlexander Duyck
This change replaces all references to the virtual address for io_tlb_end with references to the physical address io_tlb_end. The main advantage of replacing the virtual address with a physical address is that we can avoid having to do multiple translations from the virtual address to the physical one needed for testing an existing DMA address. Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-10-25genalloc: stop crashing the system when destroying a poolThadeu Lima de Souza Cascardo
The genalloc code uses the bitmap API from include/linux/bitmap.h and lib/bitmap.c, which is based on long values. Both bitmap_set from lib/bitmap.c and bitmap_set_ll, which is the lockless version from genalloc.c, use BITMAP_LAST_WORD_MASK to set the first bits in a long in the bitmap. That one uses (1 << bits) - 1, 0b111, if you are setting the first three bits. This means that the API counts from the least significant bits (LSB from now on) to the MSB. The LSB in the first long is bit 0, then. The same works for the lookup functions. The genalloc code uses longs for the bitmap, as it should. In include/linux/genalloc.h, struct gen_pool_chunk has unsigned long bits[0] as its last member. When allocating the struct, genalloc should reserve enough space for the bitmap. This should be a proper number of longs that can fit the amount of bits in the bitmap. However, genalloc allocates an integer number of bytes that fit the amount of bits, but may not be an integer amount of longs. 9 bytes, for example, could be allocated for 70 bits. This is a problem in itself if the Least Significat Bit in a long is in the byte with the largest address, which happens in Big Endian machines. This means genalloc is not allocating the byte in which it will try to set or check for a bit. This may end up in memory corruption, where genalloc will try to set the bits it has not allocated. In fact, genalloc may not set these bits because it may find them already set, because they were not zeroed since they were not allocated. And that's what causes a BUG when gen_pool_destroy is called and check for any set bits. What really happens is that genalloc uses kmalloc_node with __GFP_ZERO on gen_pool_add_virt. With SLAB and SLUB, this means the whole slab will be cleared, not only the requested bytes. Since struct gen_pool_chunk has a size that is a multiple of 8, and slab sizes are multiples of 8, we get lucky and allocate and clear the right amount of bytes. Hower, this is not the case with SLOB or with older code that did memset after allocating instead of using __GFP_ZERO. So, a simple module as this (running 3.6.0), will cause a crash when rmmod'ed. [root@phantom-lp2 foo]# cat foo.c #include <linux/kernel.h> #include <linux/module.h> #include <linux/init.h> #include <linux/genalloc.h> MODULE_LICENSE("GPL"); MODULE_VERSION("0.1"); static struct gen_pool *foo_pool; static __init int foo_init(void) { int ret; foo_pool = gen_pool_create(10, -1); if (!foo_pool) return -ENOMEM; ret = gen_pool_add(foo_pool, 0xa0000000, 32 << 10, -1); if (ret) { gen_pool_destroy(foo_pool); return ret; } return 0; } static __exit void foo_exit(void) { gen_pool_destroy(foo_pool); } module_init(foo_init); module_exit(foo_exit); [root@phantom-lp2 foo]# zcat /proc/config.gz | grep SLOB CONFIG_SLOB=y [root@phantom-lp2 foo]# insmod ./foo.ko [root@phantom-lp2 foo]# rmmod foo ------------[ cut here ]------------ kernel BUG at lib/genalloc.c:243! cpu 0x4: Vector: 700 (Program Check) at [c0000000bb0e7960] pc: c0000000003cb50c: .gen_pool_destroy+0xac/0x110 lr: c0000000003cb4fc: .gen_pool_destroy+0x9c/0x110 sp: c0000000bb0e7be0 msr: 8000000000029032 current = 0xc0000000bb0e0000 paca = 0xc000000006d30e00 softe: 0 irq_happened: 0x01 pid = 13044, comm = rmmod kernel BUG at lib/genalloc.c:243! [c0000000bb0e7ca0] d000000004b00020 .foo_exit+0x20/0x38 [foo] [c0000000bb0e7d20] c0000000000dff98 .SyS_delete_module+0x1a8/0x290 [c0000000bb0e7e30] c0000000000097d4 syscall_exit+0x0/0x94 --- Exception: c00 (System Call) at 000000800753d1a0 SP (fffd0b0e640) is in userspace Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@linux.vnet.ibm.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Benjamin Gaignard <benjamin.gaignard@stericsson.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-24dma-debug: New interfaces to debug dma mapping errorsShuah Khan
Add dma-debug interface debug_dma_mapping_error() to debug drivers that fail to check dma mapping errors on addresses returned by dma_map_single() and dma_map_page() interfaces. This interface clears a flag set by debug_dma_map_page() to indicate that dma_mapping_error() has been called by the driver. When driver does unmap, debug_dma_unmap() checks the flag and if this flag is still set, prints warning message that includes call trace that leads up to the unmap. This interface can be called from dma_mapping_error() routines to enable dma mapping error check debugging. Tested: Intel iommu and swiotlb (iommu=soft) on x86-64 with CONFIG_DMA_API_DEBUG enabled and disabled. Signed-off-by: Shuah Khan <shuah.khan@hp.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2012-10-19lib/dma-debug.c: fix __hash_bucket_find()Ming Lei
If there is only one match, the unique matched entry should be returned. Without the fix, the upcoming dma debug interfaces ("dma-debug: new interfaces to debug dma mapping errors") can't work reliably because only device and dma_addr are passed to dma_mapping_error(). Signed-off-by: Ming Lei <ming.lei@canonical.com> Reported-by: Wu Fengguang <fengguang.wu@intel.com> Cc: Joerg Roedel <joerg.roedel@amd.com> Tested-by: Shuah Khan <shuah.khan@hp.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Jakub Kicinski <kubakici@wp.pl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-14Merge branch 'modules-next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux Pull module signing support from Rusty Russell: "module signing is the highlight, but it's an all-over David Howells frenzy..." Hmm "Magrathea: Glacier signing key". Somebody has been reading too much HHGTTG. * 'modules-next' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (37 commits) X.509: Fix indefinite length element skip error handling X.509: Convert some printk calls to pr_devel asymmetric keys: fix printk format warning MODSIGN: Fix 32-bit overflow in X.509 certificate validity date checking MODSIGN: Make mrproper should remove generated files. MODSIGN: Use utf8 strings in signer's name in autogenerated X.509 certs MODSIGN: Use the same digest for the autogen key sig as for the module sig MODSIGN: Sign modules during the build process MODSIGN: Provide a script for generating a key ID from an X.509 cert MODSIGN: Implement module signature checking MODSIGN: Provide module signing public keys to the kernel MODSIGN: Automatically generate module signing keys if missing MODSIGN: Provide Kconfig options MODSIGN: Provide gitignore and make clean rules for extra files MODSIGN: Add FIPS policy module: signature checking hook X.509: Add a crypto key parser for binary (DER) X.509 certificates MPILIB: Provide a function to read raw data into an MPI X.509: Add an ASN.1 decoder X.509: Add simple ASN.1 grammar compiler ...
2012-10-11Merge branch 'akpm' (Fixups from Andrew)Linus Torvalds
Merge misc fixes from Andrew Morton: "Followups, fixes and some random stuff I found on the internet." * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (11 patches) perf: fix duplicate header inclusion memcg, kmem: fix build error when CONFIG_INET is disabled rtc: kconfig: fix RTC_INTF defaults connected to RTC_CLASS rapidio: fix comment lib/kasprintf.c: use kmalloc_track_caller() to get accurate traces for kvasprintf rapidio: update for destination ID allocation rapidio: update asynchronous discovery initialization rapidio: use msleep in discovery wait mm: compaction: fix bit ranges in {get,clear,set}_pageblock_skip() arch/powerpc/platforms/pseries/hotplug-memory.c: section removal cleanups arch/powerpc/platforms/pseries/hotplug-memory.c: fix section handling code
2012-10-11Merge branch 'for-3.7/core' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block IO update from Jens Axboe: "Core block IO bits for 3.7. Not a huge round this time, it contains: - First series from Kent cleaning up and generalizing bio allocation and freeing. - WRITE_SAME support from Martin. - Mikulas patches to prevent O_DIRECT crashes when someone changes the block size of a device. - Make bio_split() work on data-less bio's (like trim/discards). - A few other minor fixups." Fixed up silent semantic mis-merge as per Mikulas Patocka and Andrew Morton. It is due to the VM no longer using a prio-tree (see commit 6b2dbba8b6ac: "mm: replace vma prio_tree with an interval tree"). So make set_blocksize() use mapping_mapped() instead of open-coding the internal VM knowledge that has changed. * 'for-3.7/core' of git://git.kernel.dk/linux-block: (26 commits) block: makes bio_split support bio without data scatterlist: refactor the sg_nents scatterlist: add sg_nents fs: fix include/percpu-rwsem.h export error percpu-rw-semaphore: fix documentation typos fs/block_dev.c:1644:5: sparse: symbol 'blkdev_mmap' was not declared blockdev: turn a rw semaphore into a percpu rw semaphore Fix a crash when block device is read and block size is changed at the same time block: fix request_queue->flags initialization block: lift the initial queue bypass mode on blk_register_queue() instead of blk_init_allocated_queue() block: ioctl to zero block ranges block: Make blkdev_issue_zeroout use WRITE SAME block: Implement support for WRITE SAME block: Consolidate command flag and queue limit checks for merges block: Clean up special command handling logic block/blk-tag.c: Remove useless kfree block: remove the duplicated setting for congestion_threshold block: reject invalid queue attribute values block: Add bio_clone_bioset(), bio_clone_kmalloc() block: Consolidate bio_alloc_bioset(), bio_kmalloc() ...
2012-10-11lib/kasprintf.c: use kmalloc_track_caller() to get accurate traces for ↵Ezequiel Garcia
kvasprintf Previously kvasprintf() allocation was being done through kmalloc(), thus producing an inaccurate trace report. This is a common problem: in order to get accurate callsite tracing, a lib/utils function shouldn't allocate kmalloc but instead use kmalloc_track_caller. Signed-off-by: Ezequiel Garcia <elezegarcia@gmail.com> Cc: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-10X.509: Fix indefinite length element skip error handlingDavid Howells
asn1_find_indefinite_length() returns an error indicator of -1, which the caller asn1_ber_decoder() places in a size_t (which is usually unsigned) and then checks to see whether it is less than 0 (which it can't be). This can lead to the following warning: lib/asn1_decoder.c:320 asn1_ber_decoder() warn: unsigned 'len' is never less than zero. Instead, asn1_find_indefinite_length() update the caller's idea of the data cursor and length separately from returning the error code. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-10-09mm: add CONFIG_DEBUG_VM_RB build optionMichel Lespinasse
Add a CONFIG_DEBUG_VM_RB build option for the previously existing DEBUG_MM_RB code. Now that Andi Kleen modified it to avoid using recursive algorithms, we can expose it a bit more. Also extend this code to validate_mm() after stack expansion, and to check that the vma's start and last pgoffs have not changed since the nodes were inserted on the anon vma interval tree (as it is important that the nodes be reindexed after each such update). Signed-off-by: Michel Lespinasse <walken@google.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Daniel Santos <daniel.santos@pobox.com> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09mm: interval tree updatesMichel Lespinasse
Update the generic interval tree code that was introduced in "mm: replace vma prio_tree with an interval tree". Changes: - fixed 'endpoing' typo noticed by Andrew Morton - replaced include/linux/interval_tree_tmpl.h, which was used as a template (including it automatically defined the interval tree functions) with include/linux/interval_tree_generic.h, which only defines a preprocessor macro INTERVAL_TREE_DEFINE(), which itself defines the interval tree functions when invoked. Now that is a very long macro which is unfortunate, but it does make the usage sites (lib/interval_tree.c and mm/interval_tree.c) a bit nicer than previously. - make use of RB_DECLARE_CALLBACKS() in the INTERVAL_TREE_DEFINE() macro, instead of duplicating that code in the interval tree template. - replaced vma_interval_tree_add(), which was actually handling the nonlinear and interval tree cases, with vma_interval_tree_insert_after() which handles only the interval tree case and has an API that is more consistent with the other interval tree handling functions. The nonlinear case is now handled explicitly in kernel/fork.c dup_mmap(). Signed-off-by: Michel Lespinasse <walken@google.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Daniel Santos <daniel.santos@pobox.com> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09rbtree: move augmented rbtree functionality to rbtree_augmented.hMichel Lespinasse
Provide rb_insert_augmented() and rb_erase_augmented() through a new rbtree_augmented.h include file. rb_erase_augmented() is defined there as an __always_inline function, in order to allow inlining of augmented rbtree callbacks into it. Since this generates a relatively large function, each augmented rbtree user should make sure to have a single call site. Signed-off-by: Michel Lespinasse <walken@google.com> Cc: Rik van Riel <riel@redhat.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09prio_tree: removeMichel Lespinasse
After both prio_tree users have been converted to use red-black trees, there is no need to keep around the prio tree library anymore. Signed-off-by: Michel Lespinasse <walken@google.com> Cc: Rik van Riel <riel@redhat.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09mm: replace vma prio_tree with an interval treeMichel Lespinasse
Implement an interval tree as a replacement for the VMA prio_tree. The algorithms are similar to lib/interval_tree.c; however that code can't be directly reused as the interval endpoints are not explicitly stored in the VMA. So instead, the common algorithm is moved into a template and the details (node type, how to get interval endpoints from the node, etc) are filled in using the C preprocessor. Once the interval tree functions are available, using them as a replacement to the VMA prio tree is a relatively simple, mechanical job. Signed-off-by: Michel Lespinasse <walken@google.com> Cc: Rik van Riel <riel@redhat.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09rbtree: add prio tree and interval tree testsMichel Lespinasse
Patch 1 implements support for interval trees, on top of the augmented rbtree API. It also adds synthetic tests to compare the performance of interval trees vs prio trees. Short answers is that interval trees are slightly faster (~25%) on insert/erase, and much faster (~2.4 - 3x) on search. It is debatable how realistic the synthetic test is, and I have not made such measurements yet, but my impression is that interval trees would still come out faster. Patch 2 uses a preprocessor template to make the interval tree generic, and uses it as a replacement for the vma prio_tree. Patch 3 takes the other prio_tree user, kmemleak, and converts it to use a basic rbtree. We don't actually need the augmented rbtree support here because the intervals are always non-overlapping. Patch 4 removes the now-unused prio tree library. Patch 5 proposes an additional optimization to rb_erase_augmented, now providing it as an inline function so that the augmented callbacks can be inlined in. This provides an additional 5-10% performance improvement for the interval tree insert/erase benchmark. There is a maintainance cost as it exposes augmented rbtree users to some of the rbtree library internals; however I think this cost shouldn't be too high as I expect the augmented rbtree will always have much less users than the base rbtree. I should probably add a quick summary of why I think it makes sense to replace prio trees with augmented rbtree based interval trees now. One of the drivers is that we need augmented rbtrees for Rik's vma gap finding code, and once you have them, it just makes sense to use them for interval trees as well, as this is the simpler and more well known algorithm. prio trees, in comparison, seem *too* clever: they impose an additional 'heap' constraint on the tree, which they use to guarantee a faster worst-case complexity of O(k+log N) for stabbing queries in a well-balanced prio tree, vs O(k*log N) for interval trees (where k=number of matches, N=number of intervals). Now this sounds great, but in practice prio trees don't realize this theorical benefit. First, the additional constraint makes them harder to update, so that the kernel implementation has to simplify things by balancing them like a radix tree, which is not always ideal. Second, the fact that there are both index and heap properties makes both tree manipulation and search more complex, which results in a higher multiplicative time constant. As it turns out, the simple interval tree algorithm ends up running faster than the more clever prio tree. This patch: Add two test modules: - prio_tree_test measures the performance of lib/prio_tree.c, both for insertion/removal and for stabbing searches - interval_tree_test measures the performance of a library of equivalent functionality, built using the augmented rbtree support. In order to support the second test module, lib/interval_tree.c is introduced. It is kept separate from the interval_tree_test main file for two reasons: first we don't want to provide an unfair advantage over prio_tree_test by having everything in a single compilation unit, and second there is the possibility that the interval tree functionality could get some non-test users in kernel over time. Signed-off-by: Michel Lespinasse <walken@google.com> Cc: Rik van Riel <riel@redhat.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09rbtree: add RB_DECLARE_CALLBACKS() macroMichel Lespinasse
As proposed by Peter Zijlstra, this makes it easier to define the augmented rbtree callbacks. Signed-off-by: Michel Lespinasse <walken@google.com> Cc: Rik van Riel <riel@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09rbtree: remove prior augmented rbtree implementationMichel Lespinasse
convert arch/x86/mm/pat_rbtree.c to the proposed augmented rbtree api and remove the old augmented rbtree implementation. Signed-off-by: Michel Lespinasse <walken@google.com> Acked-by: Rik van Riel <riel@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09rbtree: faster augmented rbtree manipulationMichel Lespinasse
Introduce new augmented rbtree APIs that allow minimal recalculation of augmented node information. A new callback is added to the rbtree insertion and erase rebalancing functions, to be called on each tree rotations. Such rotations preserve the subtree's root augmented value, but require recalculation of the one child that was previously located at the subtree root. In the insertion case, the handcoded search phase must be updated to maintain the augmented information on insertion, and then the rbtree coloring/rebalancing algorithms keep it up to date. In the erase case, things are more complicated since it is library code that manipulates the rbtree in order to remove internal nodes. This requires a couple additional callbacks to copy a subtree's augmented value when a new root is stitched in, and to recompute augmented values down the ancestry path when a node is removed from the tree. In order to preserve maximum speed for the non-augmented case, we provide two versions of each tree manipulation function. rb_insert_augmented() is the augmented equivalent of rb_insert_color(), and rb_erase_augmented() is the augmented equivalent of rb_erase(). Signed-off-by: Michel Lespinasse <walken@google.com> Acked-by: Rik van Riel <riel@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09rbtree: augmented rbtree testMichel Lespinasse
Small test to measure the performance of augmented rbtrees. Signed-off-by: Michel Lespinasse <walken@google.com> Acked-by: Rik van Riel <riel@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09rbtree: low level optimizations in rb_erase()Michel Lespinasse
Various minor optimizations in rb_erase(): - Avoid multiple loading of node->__rb_parent_color when computing parent and color information (possibly not in close sequence, as there might be further branches in the algorithm) - In the 1-child subcase of case 1, copy the __rb_parent_color field from the erased node to the child instead of recomputing it from the desired parent and color - When searching for the erased node's successor, differentiate between cases 2 and 3 based on whether any left links were followed. This avoids a condition later down. - In case 3, keep a pointer to the erased node's right child so we don't have to refetch it later to adjust its parent. - In the no-childs subcase of cases 2 and 3, place the rebalance assigment last so that the compiler can remove the following if(rebalance) test. Also, added some comments to illustrate cases 2 and 3. Signed-off-by: Michel Lespinasse <walken@google.com> Acked-by: Rik van Riel <riel@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09rbtree: handle 1-child recoloring in rb_erase() instead of rb_erase_color()Michel Lespinasse
An interesting observation for rb_erase() is that when a node has exactly one child, the node must be black and the child must be red. An interesting consequence is that removing such a node can be done by simply replacing it with its child and making the child black, which we can do efficiently in rb_erase(). __rb_erase_color() then only needs to handle the no-childs case and can be modified accordingly. Signed-off-by: Michel Lespinasse <walken@google.com> Acked-by: Rik van Riel <riel@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09rbtree: place easiest case first in rb_erase()Michel Lespinasse
In rb_erase, move the easy case (node to erase has no more than 1 child) first. I feel the code reads easier that way. Signed-off-by: Michel Lespinasse <walken@google.com> Reviewed-by: Rik van Riel <riel@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09rbtree: add __rb_change_child() helper functionMichel Lespinasse
Add __rb_change_child() as an inline helper function to replace code that would otherwise be duplicated 4 times in the source. No changes to binary size or speed. Signed-off-by: Michel Lespinasse <walken@google.com> Reviewed-by: Rik van Riel <riel@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09rbtree test: fix sparse warning about 64-bit constantMichel Lespinasse
Just a small fix to make sparse happy. Signed-off-by: Michel Lespinasse <walken@google.com> Reported-by: Fengguang Wu <wfg@linux.intel.com> Acked-by: Rik van Riel <riel@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09rbtree: optimize fetching of sibling nodeMichel Lespinasse
When looking to fetch a node's sibling, we went through a sequence of: - check if node is the parent's left child - if it is, then fetch the parent's right child This can be replaced with: - fetch the parent's right child as an assumed sibling - check that node is NOT the fetched child This avoids fetching the parent's left child when node is actually that child. Saves a bit on code size, though it doesn't seem to make a large difference in speed. Signed-off-by: Michel Lespinasse <walken@google.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: David Woodhouse <David.Woodhouse@intel.com> Acked-by: Rik van Riel <riel@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Daniel Santos <daniel.santos@pobox.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09rbtree: coding style adjustmentsMichel Lespinasse
Set comment and indentation style to be consistent with linux coding style and the rest of the file, as suggested by Peter Zijlstra Signed-off-by: Michel Lespinasse <walken@google.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Acked-by: David Woodhouse <David.Woodhouse@intel.com> Cc: Rik van Riel <riel@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Daniel Santos <daniel.santos@pobox.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09rbtree: low level optimizations in __rb_erase_color()Michel Lespinasse
In __rb_erase_color(), we often already have pointers to the nodes being rotated and/or know what their colors must be, so we can generate more efficient code than the generic __rb_rotate_left() and __rb_rotate_right() functions. Also when the current node is red or when flipping the sibling's color, the parent is already known so we can use the more efficient rb_set_parent_color() function to set the desired color. Signed-off-by: Michel Lespinasse <walken@google.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Acked-by: David Woodhouse <David.Woodhouse@intel.com> Cc: Rik van Riel <riel@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Daniel Santos <daniel.santos@pobox.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09rbtree: optimize case selection logic in __rb_erase_color()Michel Lespinasse
In __rb_erase_color(), we have to select one of 3 cases depending on the color on the 'other' node children. If both children are black, we flip a few node colors and iterate. Otherwise, we do either one or two tree rotations, depending on the color of the 'other' child opposite to 'node', and then we are done. The corresponding logic had duplicate checks for the color of the 'other' child opposite to 'node'. It was checking it first to determine if both children are black, and then to determine how many tree rotations are required. Rearrange the logic to avoid that extra check. Signed-off-by: Michel Lespinasse <walken@google.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Acked-by: David Woodhouse <David.Woodhouse@intel.com> Cc: Rik van Riel <riel@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Daniel Santos <daniel.santos@pobox.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09rbtree: adjust node color in __rb_erase_color() only when necessaryMichel Lespinasse
In __rb_erase_color(), we were always setting a node to black after exiting the main loop. And in one case, after fixing up the tree to satisfy all rbtree invariants, we were setting the current node to root just to guarantee a loop exit, at which point the root would be set to black. However this is not necessary, as the root of an rbtree is already known to be black. The only case where the color flip is required is when we exit the loop due to the current node being red, and it's easiest to just do the flip at that point instead of doing it after the loop. [adrian.hunter@intel.com: perf tools: fix build for another rbtree.c change] Signed-off-by: Michel Lespinasse <walken@google.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Acked-by: David Woodhouse <David.Woodhouse@intel.com> Cc: Rik van Riel <riel@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Daniel Santos <daniel.santos@pobox.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09rbtree: low level optimizations in rb_insert_color()Michel Lespinasse
- Use the newly introduced rb_set_parent_color() function to flip the color of nodes whose parent is already known. - Optimize rb_parent() when the node is known to be red - there is no need to mask out the color in that case. - Flipping gparent's color to red requires us to fetch its rb_parent_color field, so we can reuse it as the parent value for the next loop iteration. - Do not use __rb_rotate_left() and __rb_rotate_right() to handle tree rotations: we already have pointers to all relevant nodes, and know their colors (either because we want to adjust it, or because we've tested it, or we can deduce it as black due to the node proximity to a known red node). So we can generate more efficient code by making use of the node pointers we already have, and setting both the parent and color attributes for nodes all at once. Also in Case 2, some node attributes don't have to be set because we know another tree rotation (Case 3) will always follow and override them. Signed-off-by: Michel Lespinasse <walken@google.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Acked-by: David Woodhouse <David.Woodhouse@intel.com> Cc: Rik van Riel <riel@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Daniel Santos <daniel.santos@pobox.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09rbtree: adjust root color in rb_insert_color() only when necessaryMichel Lespinasse
The root node of an rbtree must always be black. However, rb_insert_color() only needs to maintain this invariant when it has been broken - that is, when it exits the loop due to the current (red) node being the root. In all other cases (exiting after tree rotations, or exiting due to an existing black parent) the invariant is already satisfied, so there is no need to adjust the root node color. Signed-off-by: Michel Lespinasse <walken@google.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Acked-by: David Woodhouse <David.Woodhouse@intel.com> Cc: Rik van Riel <riel@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Daniel Santos <daniel.santos@pobox.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09rbtree: break out of rb_insert_color loop after tree rotationMichel Lespinasse
It is a well known property of rbtrees that insertion never requires more than two tree rotations. In our implementation, after one loop iteration identified one or two necessary tree rotations, we would iterate and look for more. However at that point the node's parent would always be black, which would cause us to exit the loop. We can make the code flow more obvious by just adding a break statement after the tree rotations, where we know we are done. Additionally, in the cases where two tree rotations are necessary, we don't have to update the 'node' pointer as it wouldn't be used until the next loop iteration, which we now avoid due to this break statement. Signed-off-by: Michel Lespinasse <walken@google.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Acked-by: David Woodhouse <David.Woodhouse@intel.com> Cc: Rik van Riel <riel@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Daniel Santos <daniel.santos@pobox.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09