On Wed, Sep 25, 2019 at 03:18:43PM +0800, Yunfeng Ye wrote: > sparse_buffer_init() use memblock_alloc_try_nid_raw() to allocate memory > for page management structure, if memory allocation fails from specified > node, it will fall back to allocate from other nodes. > > Normally, the page management structure will not exceed 2% of the total > memory, but a large continuous block of allocation is needed. In most > cases, memory allocation from the specified node will success always, > but a node memory become highly fragmented will fail. we expect to > allocate memory base section rather than by allocating a large block of > memory from other NUMA nodes > > Add memblock_alloc_exact_nid_raw() for this situation, which allocate > boot memory block on the exact node. If a large contiguous block memory > allocate fail in sparse_buffer_init(), it will fall back to allocate > small block memory base section. > > Signed-off-by: Yunfeng Ye <yeyunfeng@xxxxxxxxxx> One nit below, otherwise Reviewed-by: Mike Rapoport <rppt@xxxxxxxxxxxxx> > --- > v2 -> v3: > - use "bool exact_nid" instead of "int need_exact_nid" > - remove the comment "without panicking" > > v1 -> v2: > - use memblock_alloc_exact_nid_raw() rather than using a flag > > include/linux/memblock.h | 3 +++ > mm/memblock.c | 65 ++++++++++++++++++++++++++++++++++++++++-------- > mm/sparse.c | 2 +- > 3 files changed, 58 insertions(+), 12 deletions(-) > > diff --git a/include/linux/memblock.h b/include/linux/memblock.h > index f491690..b38bbef 100644 > --- a/include/linux/memblock.h > +++ b/include/linux/memblock.h > @@ -358,6 +358,9 @@ static inline phys_addr_t memblock_phys_alloc(phys_addr_t size, > MEMBLOCK_ALLOC_ACCESSIBLE); > } > > +void *memblock_alloc_exact_nid_raw(phys_addr_t size, phys_addr_t align, > + phys_addr_t min_addr, phys_addr_t max_addr, > + int nid); > void *memblock_alloc_try_nid_raw(phys_addr_t size, phys_addr_t align, > phys_addr_t min_addr, phys_addr_t max_addr, > int nid); > diff --git a/mm/memblock.c b/mm/memblock.c > index 7d4f61a..0de9d83 100644 > --- a/mm/memblock.c > +++ b/mm/memblock.c > @@ -1323,12 +1323,13 @@ __next_mem_pfn_range_in_zone(u64 *idx, struct zone *zone, > * @start: the lower bound of the memory region to allocate (phys address) > * @end: the upper bound of the memory region to allocate (phys address) > * @nid: nid of the free area to find, %NUMA_NO_NODE for any node > + * @exact_nid: control the allocation fall back to other nodes > * > * The allocation is performed from memory region limited by > * memblock.current_limit if @max_addr == %MEMBLOCK_ALLOC_ACCESSIBLE. > * > - * If the specified node can not hold the requested memory the > - * allocation falls back to any node in the system > + * If the specified node can not hold the requested memory and @exact_nid > + * is zero, the allocation falls back to any node in the system ^ is false ;-) > * > * For systems with memory mirroring, the allocation is attempted first > * from the regions with mirroring enabled and then retried from any > @@ -1342,7 +1343,8 @@ __next_mem_pfn_range_in_zone(u64 *idx, struct zone *zone, > */ > static phys_addr_t __init memblock_alloc_range_nid(phys_addr_t size, > phys_addr_t align, phys_addr_t start, > - phys_addr_t end, int nid) > + phys_addr_t end, int nid, > + bool exact_nid) > { > enum memblock_flags flags = choose_memblock_flags(); > phys_addr_t found; > @@ -1365,7 +1367,7 @@ static phys_addr_t __init memblock_alloc_range_nid(phys_addr_t size, > if (found && !memblock_reserve(found, size)) > goto done; > > - if (nid != NUMA_NO_NODE) { > + if (nid != NUMA_NO_NODE && !exact_nid) { > found = memblock_find_in_range_node(size, align, start, > end, NUMA_NO_NODE, > flags); > @@ -1413,7 +1415,8 @@ phys_addr_t __init memblock_phys_alloc_range(phys_addr_t size, > phys_addr_t start, > phys_addr_t end) > { > - return memblock_alloc_range_nid(size, align, start, end, NUMA_NO_NODE); > + return memblock_alloc_range_nid(size, align, start, end, NUMA_NO_NODE, > + false); > } > > /** > @@ -1432,7 +1435,7 @@ phys_addr_t __init memblock_phys_alloc_range(phys_addr_t size, > phys_addr_t __init memblock_phys_alloc_try_nid(phys_addr_t size, phys_addr_t align, int nid) > { > return memblock_alloc_range_nid(size, align, 0, > - MEMBLOCK_ALLOC_ACCESSIBLE, nid); > + MEMBLOCK_ALLOC_ACCESSIBLE, nid, false); > } > > /** > @@ -1442,6 +1445,7 @@ phys_addr_t __init memblock_phys_alloc_try_nid(phys_addr_t size, phys_addr_t ali > * @min_addr: the lower bound of the memory region to allocate (phys address) > * @max_addr: the upper bound of the memory region to allocate (phys address) > * @nid: nid of the free area to find, %NUMA_NO_NODE for any node > + * @exact_nid: control the allocation fall back to other nodes > * > * Allocates memory block using memblock_alloc_range_nid() and > * converts the returned physical address to virtual. > @@ -1457,7 +1461,7 @@ phys_addr_t __init memblock_phys_alloc_try_nid(phys_addr_t size, phys_addr_t ali > static void * __init memblock_alloc_internal( > phys_addr_t size, phys_addr_t align, > phys_addr_t min_addr, phys_addr_t max_addr, > - int nid) > + int nid, bool exact_nid) > { > phys_addr_t alloc; > > @@ -1469,11 +1473,13 @@ static void * __init memblock_alloc_internal( > if (WARN_ON_ONCE(slab_is_available())) > return kzalloc_node(size, GFP_NOWAIT, nid); > > - alloc = memblock_alloc_range_nid(size, align, min_addr, max_addr, nid); > + alloc = memblock_alloc_range_nid(size, align, min_addr, max_addr, nid, > + exact_nid); > > /* retry allocation without lower limit */ > if (!alloc && min_addr) > - alloc = memblock_alloc_range_nid(size, align, 0, max_addr, nid); > + alloc = memblock_alloc_range_nid(size, align, 0, max_addr, nid, > + exact_nid); > > if (!alloc) > return NULL; > @@ -1482,6 +1488,43 @@ static void * __init memblock_alloc_internal( > } > > /** > + * memblock_alloc_exact_nid_raw - allocate boot memory block on the exact node > + * without zeroing memory > + * @size: size of memory block to be allocated in bytes > + * @align: alignment of the region and block's size > + * @min_addr: the lower bound of the memory region from where the allocation > + * is preferred (phys address) > + * @max_addr: the upper bound of the memory region from where the allocation > + * is preferred (phys address), or %MEMBLOCK_ALLOC_ACCESSIBLE to > + * allocate only from memory limited by memblock.current_limit value > + * @nid: nid of the free area to find, %NUMA_NO_NODE for any node > + * > + * Public function, provides additional debug information (including caller > + * info), if enabled. Does not zero allocated memory. > + * > + * Return: > + * Virtual address of allocated memory block on success, NULL on failure. > + */ > +void * __init memblock_alloc_exact_nid_raw( > + phys_addr_t size, phys_addr_t align, > + phys_addr_t min_addr, phys_addr_t max_addr, > + int nid) > +{ > + void *ptr; > + > + memblock_dbg("%s: %llu bytes align=0x%llx nid=%d from=%pa max_addr=%pa %pS\n", > + __func__, (u64)size, (u64)align, nid, &min_addr, > + &max_addr, (void *)_RET_IP_); > + > + ptr = memblock_alloc_internal(size, align, > + min_addr, max_addr, nid, true); > + if (ptr && size > 0) > + page_init_poison(ptr, size); > + > + return ptr; > +} > + > +/** > * memblock_alloc_try_nid_raw - allocate boot memory block without zeroing > * memory and without panicking > * @size: size of memory block to be allocated in bytes > @@ -1512,7 +1555,7 @@ void * __init memblock_alloc_try_nid_raw( > &max_addr, (void *)_RET_IP_); > > ptr = memblock_alloc_internal(size, align, > - min_addr, max_addr, nid); > + min_addr, max_addr, nid, false); > if (ptr && size > 0) > page_init_poison(ptr, size); > > @@ -1547,7 +1590,7 @@ void * __init memblock_alloc_try_nid( > __func__, (u64)size, (u64)align, nid, &min_addr, > &max_addr, (void *)_RET_IP_); > ptr = memblock_alloc_internal(size, align, > - min_addr, max_addr, nid); > + min_addr, max_addr, nid, false); > if (ptr) > memset(ptr, 0, size); > > diff --git a/mm/sparse.c b/mm/sparse.c > index 72f010d..1a06471 100644 > --- a/mm/sparse.c > +++ b/mm/sparse.c > @@ -475,7 +475,7 @@ static void __init sparse_buffer_init(unsigned long size, int nid) > phys_addr_t addr = __pa(MAX_DMA_ADDRESS); > WARN_ON(sparsemap_buf); /* forgot to call sparse_buffer_fini()? */ > sparsemap_buf = > - memblock_alloc_try_nid_raw(size, PAGE_SIZE, > + memblock_alloc_exact_nid_raw(size, PAGE_SIZE, > addr, > MEMBLOCK_ALLOC_ACCESSIBLE, nid); > sparsemap_buf_end = sparsemap_buf + size; > -- > 2.7.4 > -- Sincerely yours, Mike.