SET_DMA_RESERVE(9) Memory Management in Linux SET_DMA_RESERVE(9)NAME
set_dma_reserve - set the specified number of pages reserved in the first zone
void set_dma_reserve(unsigned long new_dma_reserve);
The number of pages to mark reserved
The per-cpu batchsize and zone watermarks are determined by present_pages. In the DMA zone, a significant percentage may be consumed by
kernel image and other unfreeable allocations which can skew the watermarks badly. This function may optionally be used to account for
unfreeable pages in the first zone (e.g., ZONE_DMA). The effect will be lower watermarks and smaller per-cpu batchsize.
COPYRIGHT Kernel Hackers Manual 3.10 June 2014 SET_DMA_RESERVE(9)
Check Out this Related Man Page
MALLOC_ZONE_MALLOC(3) BSD Library Functions Manual MALLOC_ZONE_MALLOC(3)NAME
malloc_create_zone, malloc_destroy_zone, malloc_default_zone, malloc_zone_from_ptr, malloc_zone_malloc, malloc_zone_calloc,
malloc_zone_valloc, malloc_zone_realloc, malloc_zone_memalign, malloc_zone_free -- zone-based memory allocation
malloc_create_zone(vm_size_t start_size, unsigned flags);
malloc_zone_from_ptr(const void *ptr);
malloc_zone_malloc(malloc_zone_t *zone, size_t size);
malloc_zone_calloc(malloc_zone_t *zone, size_t num_items, size_t size);
malloc_zone_valloc(malloc_zone_t *zone, size_t size);
malloc_zone_realloc(malloc_zone_t *zone, void *ptr, size_t size);
malloc_zone_memalign(malloc_zone_t *zone, size_t alignment, size_t size);
malloc_zone_free(malloc_zone_t *zone, void *ptr);
The malloc_create_zone() function creates a malloc zone, advising an initial allocation of start_size bytes, and specifying flags that alter
the standard behavior of the zone. The returned malloc zone can be used to provide custom allocation and deallocation behavior, and to
retrieve additional information about the allocations in that zone.
The malloc_destroy_zone() function deallocates all memory associated with objects in zone as well as zone itself.
The malloc_default_zone() function returns the default system malloc zone, used by malloc(3), and free(3).
The malloc_zone_from_ptr() function returns a pointer to the malloc zone which contains ptr or NULL, if the pointer does not point to an
allocated object in any current malloc zone.
The malloc_zone_malloc(), malloc_zone_calloc(), malloc_zone_valloc(), malloc_zone_realloc(), malloc_zone_memalign(), and malloc_zone_free()
perform the same task on zone as their non-prefixed variants, malloc(3), calloc(3), valloc(3), realloc(3), posix_memalign(3), and free(3)
perform on the default system malloc zone.
The malloc_create_zone(), malloc_default_zone(), and malloc_zone_from_ptr() functions return a pointer to a malloc_zone_t structure, or NULL
if there was an error.
The malloc_zone_malloc(), malloc_zone_calloc(), malloc_zone_valloc(), malloc_zone_realloc(), and malloc_zone_memalign() functions return a
pointer to allocated memory. If there is an error, they return a NULL pointer. They are not required to set errno.
SEE ALSO malloc(3), posix_memalign(3)BSD Aug 13, 2008 BSD
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