user/sven/linux.git/include/linux/genalloc.h, branch v3.16.74

include/linux/genalloc.h: spinlock_t needs spinlock_types.h

2014-01-24T00:36:52Z

Compiling a C file which includes genalloc.h but without spinlock_types.h being included before, we will see the compile error below. include/linux/genalloc.h:54:2: error: unknown type name `spinlock_t' Include spinlock_types.h from genalloc.h to fix the problem. Signed-off-by: Shawn Guo Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

lib/genalloc: add a helper function for DMA buffer allocation

2013-11-13T03:09:22Z

When using pool space for DMA buffer, there might be duplicated calling of gen_pool_alloc() and gen_pool_virt_to_phys() in each implementation. Thus it's better to add a simple helper function, a compatible one to the common dma_alloc_coherent(), to save some code. Signed-off-by: Nicolin Chen Cc: "Hans J. Koch" Cc: Dan Williams Cc: Eric Miao Cc: Grant Likely Cc: Greg Kroah-Hartman Cc: Haojian Zhuang Cc: Jaroslav Kysela Cc: Kevin Hilman Cc: Liam Girdwood Cc: Mark Brown Cc: Mauro Carvalho Chehab Cc: Rob Herring Cc: Russell King Cc: Sekhar Nori Cc: Takashi Iwai Cc: Vinod Koul Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

lib/genalloc.c: fix overflow of ending address of memory chunk

2013-09-11T22:57:35Z

In struct gen_pool_chunk, end_addr means the end address of memory chunk (inclusive), but in the implementation it is treated as address + size of memory chunk (exclusive), so it points to the address plus one instead of correct ending address. The ending address of memory chunk plus one will cause overflow on the memory chunk including the last address of memory map, e.g. when starting address is 0xFFF00000 and size is 0x100000 on 32bit machine, ending address will be 0x100000000. Use correct ending address like starting address + size - 1. [akpm@linux-foundation.org: add comment to struct gen_pool_chunk:end_addr] Signed-off-by: Joonyoung Shim Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

genalloc: add devres support, allow to find a managed pool by device

2013-04-30T01:28:13Z

This patch adds three exported functions to lib/genalloc.c: devm_gen_pool_create, dev_get_gen_pool, and of_get_named_gen_pool. devm_gen_pool_create is a managed version of gen_pool_create that keeps track of the pool via devres and allows the management code to automatically destroy it after device removal. dev_get_gen_pool retrieves the gen_pool for a given device, if it was created with devm_gen_pool_create, using devres_find. of_get_named_gen_pool retrieves the gen_pool for a given device node and property name, where the property must contain a phandle pointing to a platform device node. The corresponding platform device is then fed into dev_get_gen_pool and the resulting gen_pool is returned. [akpm@linux-foundation.org: make the of_get_named_gen_pool() stub static, fixing a zillion link errors] [akpm@linux-foundation.org: squish "struct device declared inside parameter list" warning] Signed-off-by: Philipp Zabel Acked-by: Grant Likely Tested-by: Michal Simek Cc: Fabio Estevam Cc: Matt Porter Cc: Dong Aisheng Cc: Greg Kroah-Hartman Cc: Rob Herring Cc: Paul Gortmaker Cc: Javier Martin Cc: Huang Shijie Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

genalloc: make it possible to use a custom allocation algorithm

2012-10-05T18:04:57Z

Premit use of another algorithm than the default first-fit one. For example a custom algorithm could be used to manage alignment requirements. As I can't predict all the possible requirements/needs for all allocation uses cases, I add a "free" field 'void *data' to pass any needed information to the allocation function. For example 'data' could be used to handle a structure where you store the alignment, the expected memory bank, the requester device, or any information that could influence the allocation algorithm. An usage example may look like this: struct my_pool_constraints { int align; int bank; ... }; unsigned long my_custom_algo(unsigned long *map, unsigned long size, unsigned long start, unsigned int nr, void *data) { struct my_pool_constraints *constraints = data; ... deal with allocation contraints ... return the index in bitmap where perform the allocation } void create_my_pool() { struct my_pool_constraints c; struct gen_pool *pool = gen_pool_create(...); gen_pool_add(pool, ...); gen_pool_set_algo(pool, my_custom_algo, &c); } Add of best-fit algorithm function: most of the time best-fit is slower then first-fit but memory fragmentation is lower. The random buffer allocation/free tests don't show any arithmetic relation between the allocation time and fragmentation but the best-fit algorithm is sometime able to perform the allocation when the first-fit can't. This new algorithm help to remove static allocations on ESRAM, a small but fast on-chip RAM of few KB, used for high-performance uses cases like DMA linked lists, graphic accelerators, encoders/decoders. On the Ux500 (in the ARM tree) we have define 5 ESRAM banks of 128 KB each and use of static allocations becomes unmaintainable: cd arch/arm/mach-ux500 && grep -r ESRAM . ./include/mach/db8500-regs.h:/* Base address and bank offsets for ESRAM */ ./include/mach/db8500-regs.h:#define U8500_ESRAM_BASE 0x40000000 ./include/mach/db8500-regs.h:#define U8500_ESRAM_BANK_SIZE 0x00020000 ./include/mach/db8500-regs.h:#define U8500_ESRAM_BANK0 U8500_ESRAM_BASE ./include/mach/db8500-regs.h:#define U8500_ESRAM_BANK1 (U8500_ESRAM_BASE + U8500_ESRAM_BANK_SIZE) ./include/mach/db8500-regs.h:#define U8500_ESRAM_BANK2 (U8500_ESRAM_BANK1 + U8500_ESRAM_BANK_SIZE) ./include/mach/db8500-regs.h:#define U8500_ESRAM_BANK3 (U8500_ESRAM_BANK2 + U8500_ESRAM_BANK_SIZE) ./include/mach/db8500-regs.h:#define U8500_ESRAM_BANK4 (U8500_ESRAM_BANK3 + U8500_ESRAM_BANK_SIZE) ./include/mach/db8500-regs.h:#define U8500_ESRAM_DMA_LCPA_OFFSET 0x10000 ./include/mach/db8500-regs.h:#define U8500_DMA_LCPA_BASE (U8500_ESRAM_BANK0 + U8500_ESRAM_DMA_LCPA_OFFSET) ./include/mach/db8500-regs.h:#define U8500_DMA_LCLA_BASE U8500_ESRAM_BANK4 I want to use genalloc to do dynamic allocations but I need to be able to fine tune the allocation algorithm. I my case best-fit algorithm give better results than first-fit, but it will not be true for every use case. Signed-off-by: Benjamin Gaignard Cc: Huang Ying Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

lib, Make gen_pool memory allocator lockless

2011-08-03T15:15:57Z

This version of the gen_pool memory allocator supports lockless operation. This makes it safe to use in NMI handlers and other special unblockable contexts that could otherwise deadlock on locks. This is implemented by using atomic operations and retries on any conflicts. The disadvantage is that there may be livelocks in extreme cases. For better scalability, one gen_pool allocator can be used for each CPU. The lockless operation only works if there is enough memory available. If new memory is added to the pool a lock has to be still taken. So any user relying on locklessness has to ensure that sufficient memory is preallocated. The basic atomic operation of this allocator is cmpxchg on long. On architectures that don't have NMI-safe cmpxchg implementation, the allocator can NOT be used in NMI handler. So code uses the allocator in NMI handler should depend on CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG. Signed-off-by: Huang Ying Reviewed-by: Andi Kleen Reviewed-by: Mathieu Desnoyers Cc: Andrew Morton Signed-off-by: Len Brown

lib/genalloc.c: add support for specifying the physical address

2011-05-25T15:39:54Z

So we can specify the virtual address as the base of the pool chunk and then get physical addresses for hardware IP. For example on at91 we will use this on spi, uart or macb Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD Cc: Nicolas Ferre Cc: Patrice VILCHEZ Cc: Jes Sorensen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

include/linux/genalloc.h: add multiple-inclusion guards

2011-05-25T15:39:53Z

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD Cc: Nicolas Ferre Cc: Patrice VILCHEZ Cc: Jes Sorensen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] LIB: add gen_pool_destroy()

2006-10-02T14:57:12Z

Modules using the genpool allocator need to be able to destroy the data structure when unloading. Signed-off-by: Steve Wise Cc: Randy Dunlap Cc: Dean Nelson Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] change gen_pool allocator to not touch managed memory

2006-06-23T14:42:49Z

Modify the gen_pool allocator (lib/genalloc.c) to utilize a bitmap scheme instead of the buddy scheme. The purpose of this change is to eliminate the touching of the actual memory being allocated. Since the change modifies the interface, a change to the uncached allocator (arch/ia64/kernel/uncached.c) is also required. Both Andrey Volkov and Jes Sorenson have expressed a desire that the gen_pool allocator not write to the memory being managed. See the following: http://marc.theaimsgroup.com/?l=linux-kernel&m=113518602713125&w=2 http://marc.theaimsgroup.com/?l=linux-kernel&m=113533568827916&w=2 Signed-off-by: Dean Nelson Cc: Andrey Volkov Acked-by: Jes Sorensen Cc: "Luck, Tony" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds