diff options
| -rw-r--r-- | Documentation/kernel-parameters.txt | 10 | ||||
| -rw-r--r-- | arch/x86/mm/pageattr.c | 20 | ||||
| -rw-r--r-- | include/linux/percpu.h | 16 | ||||
| -rw-r--r-- | mm/percpu.c | 241 |
4 files changed, 6 insertions, 281 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index dee9ce2..e710093 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1920,11 +1920,11 @@ and is between 256 and 4096 characters. It is defined in the file See arch/parisc/kernel/pdc_chassis.c percpu_alloc= Select which percpu first chunk allocator to use. - Currently supported values are "embed", "page" and - "lpage". Archs may support subset or none of the - selections. See comments in mm/percpu.c for details - on each allocator. This parameter is primarily for - debugging and performance comparison. + Currently supported values are "embed" and "page". + Archs may support subset or none of the selections. + See comments in mm/percpu.c for details on each + allocator. This parameter is primarily for debugging + and performance comparison. pf. [PARIDE] See Documentation/blockdev/paride.txt. diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index dce282f..f53cfc7 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pageattr.c @@ -687,7 +687,7 @@ static int cpa_process_alias(struct cpa_data *cpa) { struct cpa_data alias_cpa; unsigned long laddr = (unsigned long)__va(cpa->pfn << PAGE_SHIFT); - unsigned long vaddr, remapped; + unsigned long vaddr; int ret; if (cpa->pfn >= max_pfn_mapped) @@ -745,24 +745,6 @@ static int cpa_process_alias(struct cpa_data *cpa) } #endif - /* - * If the PMD page was partially used for per-cpu remapping, - * the recycled area needs to be split and modified. Because - * the area is always proper subset of a PMD page - * cpa->numpages is guaranteed to be 1 for these areas, so - * there's no need to loop over and check for further remaps. - */ - remapped = (unsigned long)pcpu_lpage_remapped((void *)laddr); - if (remapped) { - WARN_ON(cpa->numpages > 1); - alias_cpa = *cpa; - alias_cpa.vaddr = &remapped; - alias_cpa.flags &= ~(CPA_PAGES_ARRAY | CPA_ARRAY); - ret = __change_page_attr_set_clr(&alias_cpa, 0); - if (ret) - return ret; - } - return 0; } diff --git a/include/linux/percpu.h b/include/linux/percpu.h index 2535993..878836c 100644 --- a/include/linux/percpu.h +++ b/include/linux/percpu.h @@ -82,7 +82,6 @@ enum pcpu_fc { PCPU_FC_AUTO, PCPU_FC_EMBED, PCPU_FC_PAGE, - PCPU_FC_LPAGE, PCPU_FC_NR, }; @@ -95,7 +94,6 @@ typedef void * (*pcpu_fc_alloc_fn_t)(unsigned int cpu, size_t size, typedef void (*pcpu_fc_free_fn_t)(void *ptr, size_t size); typedef void (*pcpu_fc_populate_pte_fn_t)(unsigned long addr); typedef int (pcpu_fc_cpu_distance_fn_t)(unsigned int from, unsigned int to); -typedef void (*pcpu_fc_map_fn_t)(void *ptr, size_t size, void *addr); extern struct pcpu_alloc_info * __init pcpu_alloc_alloc_info(int nr_groups, int nr_units); @@ -124,20 +122,6 @@ extern int __init pcpu_page_first_chunk(size_t reserved_size, pcpu_fc_populate_pte_fn_t populate_pte_fn); #endif -#ifdef CONFIG_NEED_PER_CPU_LPAGE_FIRST_CHUNK -extern int __init pcpu_lpage_first_chunk(const struct pcpu_alloc_info *ai, - pcpu_fc_alloc_fn_t alloc_fn, - pcpu_fc_free_fn_t free_fn, - pcpu_fc_map_fn_t map_fn); - -extern void *pcpu_lpage_remapped(void *kaddr); -#else -static inline void *pcpu_lpage_remapped(void *kaddr) -{ - return NULL; -} -#endif - /* * Use this to get to a cpu's version of the per-cpu object * dynamically allocated. Non-atomic access to the current CPU's diff --git a/mm/percpu.c b/mm/percpu.c index c2826d0..7793392 100644 --- a/mm/percpu.c +++ b/mm/percpu.c @@ -1713,7 +1713,6 @@ const char *pcpu_fc_names[PCPU_FC_NR] __initdata = { [PCPU_FC_AUTO] = "auto", [PCPU_FC_EMBED] = "embed", [PCPU_FC_PAGE] = "page", - [PCPU_FC_LPAGE] = "lpage", }; enum pcpu_fc pcpu_chosen_fc __initdata = PCPU_FC_AUTO; @@ -1730,10 +1729,6 @@ static int __init percpu_alloc_setup(char *str) else if (!strcmp(str, "page")) pcpu_chosen_fc = PCPU_FC_PAGE; #endif -#ifdef CONFIG_NEED_PER_CPU_LPAGE_FIRST_CHUNK - else if (!strcmp(str, "lpage")) - pcpu_chosen_fc = PCPU_FC_LPAGE; -#endif else pr_warning("PERCPU: unknown allocator %s specified\n", str); @@ -1970,242 +1965,6 @@ out_free_ar: } #endif /* CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK */ -#ifdef CONFIG_NEED_PER_CPU_LPAGE_FIRST_CHUNK -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 struct pcpu_alloc_info *ai, - unsigned int *cpup) -{ - int group, cunit; - - for (group = 0, cunit = 0; group < ai->nr_groups; group++) { - const struct pcpu_group_info *gi = &ai->groups[group]; - - if (unit < cunit + gi->nr_units) { - if (cpup) - *cpup = gi->cpu_map[unit - cunit]; - return true; - } - cunit += gi->nr_units; - } - - return false; -} - -static int __init pcpul_cpu_to_unit(int cpu, const struct pcpu_alloc_info *ai) -{ - int group, unit, i; - - for (group = 0, unit = 0; group < ai->nr_groups; group++, unit += i) { - const struct pcpu_group_info *gi = &ai->groups[group]; - - for (i = 0; i < gi->nr_units; i++) - if (gi->cpu_map[i] == cpu) - return unit + i; - } - BUG(); -} - -/** - * pcpu_lpage_first_chunk - remap the first percpu chunk using large page - * @ai: pcpu_alloc_info - * @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 provide fully initialized - * @ai. This can be done using pcpu_build_alloc_info(). 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: - * 0 on success, -errno on failure. - */ -int __init pcpu_lpage_first_chunk(const struct pcpu_alloc_info *ai, - 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; - const size_t lpage_size = ai->atom_size; - size_t chunk_size, map_size; - unsigned int cpu; - int i, j, unit, nr_units, rc; - - nr_units = 0; - for (i = 0; i < ai->nr_groups; i++) - nr_units += ai->groups[i].nr_units; - - chunk_size = ai->unit_size * nr_units; - BUG_ON(chunk_size % lpage_size); - - pcpul_size = ai->static_size + ai->reserved_size + ai->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 / ai->unit_size; - int last_unit = (offset + lpage_size - 1) / ai->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, ai, &cpu)) - goto found; - continue; - found: - ptr = alloc_fn(cpu, lpage_size, 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 * ai->unit_size; - size_t end = start + ai->unit_size; - size_t off, next; - - /* don't free used part of occupied unit */ - if (pcpul_unit_to_cpu(unit, ai, 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, ai->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 + pcpul_cpu_to_unit(cpu, ai) * ai->unit_size, - __per_cpu_load, ai->static_size); - - /* we're ready, commit */ - pr_info("PERCPU: large pages @%p s%zu r%zu d%zu u%zu\n", - vm.addr, ai->static_size, ai->reserved_size, ai->dyn_size, - ai->unit_size); - - rc = pcpu_setup_first_chunk(ai, vm.addr); - - /* - * 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 rc; - -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; -} -#endif /* CONFIG_NEED_PER_CPU_LPAGE_FIRST_CHUNK */ - /* * Generic percpu area setup. * |
