- return ret;
-}
-
-/*
- * Large page remapping first chunk setup helper
- */
-#ifdef CONFIG_NEED_MULTIPLE_NODES
-
-/**
- * pcpu_lpage_build_unit_map - build unit_map for large page remapping
- * @static_size: the size of static percpu area in bytes
- * @reserved_size: the size of reserved percpu area in bytes
- * @dyn_sizep: in/out parameter for dynamic size, -1 for auto
- * @unit_sizep: out parameter for unit size
- * @unit_map: unit_map to be filled
- * @cpu_distance_fn: callback to determine distance between cpus
- *
- * This function builds cpu -> unit map and determine other parameters
- * considering needed percpu size, large page size and distances
- * between CPUs in NUMA.
- *
- * CPUs which are of LOCAL_DISTANCE both ways are grouped together and
- * may share units in the same large page. The returned configuration
- * is guaranteed to have CPUs on different nodes on different large
- * pages and >=75% usage of allocated virtual address space.
- *
- * RETURNS:
- * On success, fills in @unit_map, sets *@dyn_sizep, *@unit_sizep and
- * returns the number of units to be allocated. -errno on failure.
- */
-int __init pcpu_lpage_build_unit_map(size_t static_size, size_t reserved_size,
- ssize_t *dyn_sizep, size_t *unit_sizep,
- size_t lpage_size, int *unit_map,
- pcpu_fc_cpu_distance_fn_t cpu_distance_fn)
-{
- static int group_map[NR_CPUS] __initdata;
- static int group_cnt[NR_CPUS] __initdata;
- int group_cnt_max = 0;
- size_t size_sum, min_unit_size, alloc_size;
- int upa, max_upa, uninitialized_var(best_upa); /* units_per_alloc */
- int last_allocs;
- unsigned int cpu, tcpu;
- int group, unit;
-
- /*
- * Determine min_unit_size, alloc_size and max_upa such that
- * alloc_size is multiple of lpage_size and is the smallest
- * which can accomodate 4k aligned segments which are equal to
- * or larger than min_unit_size.
- */
- size_sum = pcpu_calc_fc_sizes(static_size, reserved_size, dyn_sizep);
- min_unit_size = max_t(size_t, size_sum, PCPU_MIN_UNIT_SIZE);
-
- alloc_size = roundup(min_unit_size, lpage_size);
- upa = alloc_size / min_unit_size;
- while (alloc_size % upa || ((alloc_size / upa) & ~PAGE_MASK))
- upa--;
- max_upa = upa;
-
- /* group cpus according to their proximity */
- for_each_possible_cpu(cpu) {
- group = 0;
- next_group:
- for_each_possible_cpu(tcpu) {
- if (cpu == tcpu)
- break;
- if (group_map[tcpu] == group &&
- (cpu_distance_fn(cpu, tcpu) > LOCAL_DISTANCE ||
- cpu_distance_fn(tcpu, cpu) > LOCAL_DISTANCE)) {
- group++;
- goto next_group;
- }
- }
- group_map[cpu] = group;
- group_cnt[group]++;
- group_cnt_max = max(group_cnt_max, group_cnt[group]);
- }
-
- /*
- * Expand unit size until address space usage goes over 75%
- * and then as much as possible without using more address
- * space.
- */
- last_allocs = INT_MAX;
- for (upa = max_upa; upa; upa--) {
- int allocs = 0, wasted = 0;
-
- if (alloc_size % upa || ((alloc_size / upa) & ~PAGE_MASK))
- continue;
-
- for (group = 0; group_cnt[group]; group++) {
- int this_allocs = DIV_ROUND_UP(group_cnt[group], upa);
- allocs += this_allocs;
- wasted += this_allocs * upa - group_cnt[group];
- }
-
- /*
- * Don't accept if wastage is over 25%. The
- * greater-than comparison ensures upa==1 always
- * passes the following check.
- */
- if (wasted > num_possible_cpus() / 3)
- continue;
-
- /* and then don't consume more memory */
- if (allocs > last_allocs)
- break;
- last_allocs = allocs;
- best_upa = upa;
- }
- *unit_sizep = alloc_size / best_upa;
-
- /* assign units to cpus accordingly */
- unit = 0;
- for (group = 0; group_cnt[group]; group++) {
- for_each_possible_cpu(cpu)
- if (group_map[cpu] == group)
- unit_map[cpu] = unit++;
- unit = roundup(unit, best_upa);
- }
-
- return unit; /* unit contains aligned number of units */
-}
-
-struct pcpul_ent {
- void *ptr;
- void *map_addr;
-};
-
-static size_t pcpul_size;
-static size_t pcpul_lpage_size;
-static int pcpul_nr_lpages;
-static struct pcpul_ent *pcpul_map;
-
-static bool __init pcpul_unit_to_cpu(int unit, const int *unit_map,
- unsigned int *cpup)
-{
- unsigned int cpu;
-
- for_each_possible_cpu(cpu)
- if (unit_map[cpu] == unit) {
- if (cpup)
- *cpup = cpu;
- return true;
- }
-
- return false;
-}
-
-static void __init pcpul_lpage_dump_cfg(const char *lvl, size_t static_size,
- size_t reserved_size, size_t dyn_size,
- size_t unit_size, size_t lpage_size,
- const int *unit_map, int nr_units)
-{
- int width = 1, v = nr_units;
- char empty_str[] = "--------";
- int upl, lpl; /* units per lpage, lpage per line */
- unsigned int cpu;
- int lpage, unit;
-
- while (v /= 10)
- width++;
- empty_str[min_t(int, width, sizeof(empty_str) - 1)] = '\0';
-
- upl = max_t(int, lpage_size / unit_size, 1);
- lpl = rounddown_pow_of_two(max_t(int, 60 / (upl * (width + 1) + 2), 1));
-
- printk("%spcpu-lpage: sta/res/dyn=%zu/%zu/%zu unit=%zu lpage=%zu", lvl,
- static_size, reserved_size, dyn_size, unit_size, lpage_size);
-
- for (lpage = 0, unit = 0; unit < nr_units; unit++) {
- if (!(unit % upl)) {
- if (!(lpage++ % lpl)) {
- printk("\n");
- printk("%spcpu-lpage: ", lvl);
- } else
- printk("| ");
- }
- if (pcpul_unit_to_cpu(unit, unit_map, &cpu))
- printk("%0*d ", width, cpu);
- else
- printk("%s ", empty_str);
- }
- printk("\n");
-}
-
-/**
- * pcpu_lpage_first_chunk - remap the first percpu chunk using large page
- * @static_size: the size of static percpu area in bytes
- * @reserved_size: the size of reserved percpu area in bytes
- * @dyn_size: free size for dynamic allocation in bytes
- * @unit_size: unit size in bytes
- * @lpage_size: the size of a large page
- * @unit_map: cpu -> unit mapping
- * @nr_units: the number of units
- * @alloc_fn: function to allocate percpu lpage, always called with lpage_size
- * @free_fn: function to free percpu memory, @size <= lpage_size
- * @map_fn: function to map percpu lpage, always called with lpage_size
- *
- * This allocator uses large page to build and map the first chunk.
- * Unlike other helpers, the caller should always specify @dyn_size
- * and @unit_size. These parameters along with @unit_map and
- * @nr_units can be determined using pcpu_lpage_build_unit_map().
- * This two stage initialization is to allow arch code to evaluate the
- * parameters before committing to it.
- *
- * Large pages are allocated as directed by @unit_map and other
- * parameters and mapped to vmalloc space. Unused holes are returned
- * to the page allocator. Note that these holes end up being actively
- * mapped twice - once to the physical mapping and to the vmalloc area
- * for the first percpu chunk. Depending on architecture, this might
- * cause problem when changing page attributes of the returned area.
- * These double mapped areas can be detected using
- * pcpu_lpage_remapped().
- *
- * RETURNS:
- * The determined pcpu_unit_size which can be used to initialize
- * percpu access on success, -errno on failure.
- */
-ssize_t __init pcpu_lpage_first_chunk(size_t static_size, size_t reserved_size,
- size_t dyn_size, size_t unit_size,
- size_t lpage_size, const int *unit_map,
- int nr_units,
- pcpu_fc_alloc_fn_t alloc_fn,
- pcpu_fc_free_fn_t free_fn,
- pcpu_fc_map_fn_t map_fn)
-{
- static struct vm_struct vm;
- size_t chunk_size = unit_size * nr_units;
- size_t map_size;
- unsigned int cpu;
- ssize_t ret;
- int i, j, unit;
-
- pcpul_lpage_dump_cfg(KERN_DEBUG, static_size, reserved_size, dyn_size,
- unit_size, lpage_size, unit_map, nr_units);
-
- BUG_ON(chunk_size % lpage_size);
-
- pcpul_size = static_size + reserved_size + dyn_size;
- pcpul_lpage_size = lpage_size;
- pcpul_nr_lpages = chunk_size / lpage_size;
-
- /* allocate pointer array and alloc large pages */
- map_size = pcpul_nr_lpages * sizeof(pcpul_map[0]);
- pcpul_map = alloc_bootmem(map_size);
-
- /* allocate all pages */
- for (i = 0; i < pcpul_nr_lpages; i++) {
- size_t offset = i * lpage_size;
- int first_unit = offset / unit_size;
- int last_unit = (offset + lpage_size - 1) / unit_size;
- void *ptr;
-
- /* find out which cpu is mapped to this unit */
- for (unit = first_unit; unit <= last_unit; unit++)
- if (pcpul_unit_to_cpu(unit, unit_map, &cpu))
- goto found;
- continue;
- found:
- ptr = alloc_fn(cpu, lpage_size);
- if (!ptr) {
- pr_warning("PERCPU: failed to allocate large page "
- "for cpu%u\n", cpu);
- goto enomem;
- }
-
- pcpul_map[i].ptr = ptr;
- }
-
- /* return unused holes */
- for (unit = 0; unit < nr_units; unit++) {
- size_t start = unit * unit_size;
- size_t end = start + unit_size;
- size_t off, next;
-
- /* don't free used part of occupied unit */
- if (pcpul_unit_to_cpu(unit, unit_map, NULL))
- start += pcpul_size;
-
- /* unit can span more than one page, punch the holes */
- for (off = start; off < end; off = next) {
- void *ptr = pcpul_map[off / lpage_size].ptr;
- next = min(roundup(off + 1, lpage_size), end);
- if (ptr)
- free_fn(ptr + off % lpage_size, next - off);
- }
- }
-
- /* allocate address, map and copy */
- vm.flags = VM_ALLOC;
- vm.size = chunk_size;
- vm_area_register_early(&vm, unit_size);
-
- for (i = 0; i < pcpul_nr_lpages; i++) {
- if (!pcpul_map[i].ptr)
- continue;
- pcpul_map[i].map_addr = vm.addr + i * lpage_size;
- map_fn(pcpul_map[i].ptr, lpage_size, pcpul_map[i].map_addr);
- }
-
- for_each_possible_cpu(cpu)
- memcpy(vm.addr + unit_map[cpu] * unit_size, __per_cpu_load,
- static_size);
-
- /* we're ready, commit */
- pr_info("PERCPU: large pages @%p s%zu r%zu d%zu u%zu\n",
- vm.addr, static_size, reserved_size, dyn_size, unit_size);
-
- ret = pcpu_setup_first_chunk(static_size, reserved_size, dyn_size,
- unit_size, vm.addr, unit_map);
-
- /*
- * Sort pcpul_map array for pcpu_lpage_remapped(). Unmapped
- * lpages are pushed to the end and trimmed.
- */
- for (i = 0; i < pcpul_nr_lpages - 1; i++)
- for (j = i + 1; j < pcpul_nr_lpages; j++) {
- struct pcpul_ent tmp;
-
- if (!pcpul_map[j].ptr)
- continue;
- if (pcpul_map[i].ptr &&
- pcpul_map[i].ptr < pcpul_map[j].ptr)
- continue;
-
- tmp = pcpul_map[i];
- pcpul_map[i] = pcpul_map[j];
- pcpul_map[j] = tmp;
- }
-
- while (pcpul_nr_lpages && !pcpul_map[pcpul_nr_lpages - 1].ptr)
- pcpul_nr_lpages--;
-
- return ret;
-
-enomem:
- for (i = 0; i < pcpul_nr_lpages; i++)
- if (pcpul_map[i].ptr)
- free_fn(pcpul_map[i].ptr, lpage_size);
- free_bootmem(__pa(pcpul_map), map_size);
- return -ENOMEM;
-}
-
-/**
- * pcpu_lpage_remapped - determine whether a kaddr is in pcpul recycled area
- * @kaddr: the kernel address in question
- *
- * Determine whether @kaddr falls in the pcpul recycled area. This is
- * used by pageattr to detect VM aliases and break up the pcpu large
- * page mapping such that the same physical page is not mapped under
- * different attributes.
- *
- * The recycled area is always at the tail of a partially used large
- * page.
- *
- * RETURNS:
- * Address of corresponding remapped pcpu address if match is found;
- * otherwise, NULL.
- */
-void *pcpu_lpage_remapped(void *kaddr)
-{
- unsigned long lpage_mask = pcpul_lpage_size - 1;
- void *lpage_addr = (void *)((unsigned long)kaddr & ~lpage_mask);
- unsigned long offset = (unsigned long)kaddr & lpage_mask;
- int left = 0, right = pcpul_nr_lpages - 1;
- int pos;
-
- /* pcpul in use at all? */
- if (!pcpul_map)
- return NULL;
-
- /* okay, perform binary search */
- while (left <= right) {
- pos = (left + right) / 2;
-
- if (pcpul_map[pos].ptr < lpage_addr)
- left = pos + 1;
- else if (pcpul_map[pos].ptr > lpage_addr)
- right = pos - 1;
- else
- return pcpul_map[pos].map_addr + offset;
- }
-
- return NULL;