From: Tejun Heo Date: Tue, 21 Jul 2009 12:18:35 +0000 (+0900) Subject: percpu: kill legacy percpu allocator X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=23fb064bb96f001ecb8682129f7ee1bc1ca691bc;p=GitHub%2Fexynos8895%2Fandroid_kernel_samsung_universal8895.git percpu: kill legacy percpu allocator With ia64 converted, there's no arch left which still uses legacy percpu allocator. Kill it. Signed-off-by: Tejun Heo Delightedly-acked-by: Rusty Russell Cc: Ingo Molnar Cc: Christoph Lameter --- diff --git a/include/linux/percpu.h b/include/linux/percpu.h index 878836ca999c..5baf5b8788fb 100644 --- a/include/linux/percpu.h +++ b/include/linux/percpu.h @@ -34,8 +34,6 @@ #ifdef CONFIG_SMP -#ifndef CONFIG_HAVE_LEGACY_PER_CPU_AREA - /* minimum unit size, also is the maximum supported allocation size */ #define PCPU_MIN_UNIT_SIZE PFN_ALIGN(64 << 10) @@ -130,28 +128,6 @@ extern int __init pcpu_page_first_chunk(size_t reserved_size, #define per_cpu_ptr(ptr, cpu) SHIFT_PERCPU_PTR((ptr), per_cpu_offset((cpu))) extern void *__alloc_reserved_percpu(size_t size, size_t align); - -#else /* CONFIG_HAVE_LEGACY_PER_CPU_AREA */ - -struct percpu_data { - void *ptrs[1]; -}; - -/* pointer disguising messes up the kmemleak objects tracking */ -#ifndef CONFIG_DEBUG_KMEMLEAK -#define __percpu_disguise(pdata) (struct percpu_data *)~(unsigned long)(pdata) -#else -#define __percpu_disguise(pdata) (struct percpu_data *)(pdata) -#endif - -#define per_cpu_ptr(ptr, cpu) \ -({ \ - struct percpu_data *__p = __percpu_disguise(ptr); \ - (__typeof__(ptr))__p->ptrs[(cpu)]; \ -}) - -#endif /* CONFIG_HAVE_LEGACY_PER_CPU_AREA */ - extern void *__alloc_percpu(size_t size, size_t align); extern void free_percpu(void *__pdata); diff --git a/kernel/module.c b/kernel/module.c index 8b7d8805819d..64787cddeb5e 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -370,8 +370,6 @@ EXPORT_SYMBOL_GPL(find_module); #ifdef CONFIG_SMP -#ifndef CONFIG_HAVE_LEGACY_PER_CPU_AREA - static void *percpu_modalloc(unsigned long size, unsigned long align, const char *name) { @@ -395,154 +393,6 @@ static void percpu_modfree(void *freeme) free_percpu(freeme); } -#else /* ... CONFIG_HAVE_LEGACY_PER_CPU_AREA */ - -/* Number of blocks used and allocated. */ -static unsigned int pcpu_num_used, pcpu_num_allocated; -/* Size of each block. -ve means used. */ -static int *pcpu_size; - -static int split_block(unsigned int i, unsigned short size) -{ - /* Reallocation required? */ - if (pcpu_num_used + 1 > pcpu_num_allocated) { - int *new; - - new = krealloc(pcpu_size, sizeof(new[0])*pcpu_num_allocated*2, - GFP_KERNEL); - if (!new) - return 0; - - pcpu_num_allocated *= 2; - pcpu_size = new; - } - - /* Insert a new subblock */ - memmove(&pcpu_size[i+1], &pcpu_size[i], - sizeof(pcpu_size[0]) * (pcpu_num_used - i)); - pcpu_num_used++; - - pcpu_size[i+1] -= size; - pcpu_size[i] = size; - return 1; -} - -static inline unsigned int block_size(int val) -{ - if (val < 0) - return -val; - return val; -} - -static void *percpu_modalloc(unsigned long size, unsigned long align, - const char *name) -{ - unsigned long extra; - unsigned int i; - void *ptr; - int cpu; - - if (align > PAGE_SIZE) { - printk(KERN_WARNING "%s: per-cpu alignment %li > %li\n", - name, align, PAGE_SIZE); - align = PAGE_SIZE; - } - - ptr = __per_cpu_start; - for (i = 0; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) { - /* Extra for alignment requirement. */ - extra = ALIGN((unsigned long)ptr, align) - (unsigned long)ptr; - BUG_ON(i == 0 && extra != 0); - - if (pcpu_size[i] < 0 || pcpu_size[i] < extra + size) - continue; - - /* Transfer extra to previous block. */ - if (pcpu_size[i-1] < 0) - pcpu_size[i-1] -= extra; - else - pcpu_size[i-1] += extra; - pcpu_size[i] -= extra; - ptr += extra; - - /* Split block if warranted */ - if (pcpu_size[i] - size > sizeof(unsigned long)) - if (!split_block(i, size)) - return NULL; - - /* add the per-cpu scanning areas */ - for_each_possible_cpu(cpu) - kmemleak_alloc(ptr + per_cpu_offset(cpu), size, 0, - GFP_KERNEL); - - /* Mark allocated */ - pcpu_size[i] = -pcpu_size[i]; - return ptr; - } - - printk(KERN_WARNING "Could not allocate %lu bytes percpu data\n", - size); - return NULL; -} - -static void percpu_modfree(void *freeme) -{ - unsigned int i; - void *ptr = __per_cpu_start + block_size(pcpu_size[0]); - int cpu; - - /* First entry is core kernel percpu data. */ - for (i = 1; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) { - if (ptr == freeme) { - pcpu_size[i] = -pcpu_size[i]; - goto free; - } - } - BUG(); - - free: - /* remove the per-cpu scanning areas */ - for_each_possible_cpu(cpu) - kmemleak_free(freeme + per_cpu_offset(cpu)); - - /* Merge with previous? */ - if (pcpu_size[i-1] >= 0) { - pcpu_size[i-1] += pcpu_size[i]; - pcpu_num_used--; - memmove(&pcpu_size[i], &pcpu_size[i+1], - (pcpu_num_used - i) * sizeof(pcpu_size[0])); - i--; - } - /* Merge with next? */ - if (i+1 < pcpu_num_used && pcpu_size[i+1] >= 0) { - pcpu_size[i] += pcpu_size[i+1]; - pcpu_num_used--; - memmove(&pcpu_size[i+1], &pcpu_size[i+2], - (pcpu_num_used - (i+1)) * sizeof(pcpu_size[0])); - } -} - -static int percpu_modinit(void) -{ - pcpu_num_used = 2; - pcpu_num_allocated = 2; - pcpu_size = kmalloc(sizeof(pcpu_size[0]) * pcpu_num_allocated, - GFP_KERNEL); - /* Static in-kernel percpu data (used). */ - pcpu_size[0] = -(__per_cpu_end-__per_cpu_start); - /* Free room. */ - pcpu_size[1] = PERCPU_ENOUGH_ROOM + pcpu_size[0]; - if (pcpu_size[1] < 0) { - printk(KERN_ERR "No per-cpu room for modules.\n"); - pcpu_num_used = 1; - } - - return 0; -} -__initcall(percpu_modinit); - -#endif /* CONFIG_HAVE_LEGACY_PER_CPU_AREA */ - static unsigned int find_pcpusec(Elf_Ehdr *hdr, Elf_Shdr *sechdrs, const char *secstrings) diff --git a/mm/Makefile b/mm/Makefile index ebf849042ed3..82131d0f8d85 100644 --- a/mm/Makefile +++ b/mm/Makefile @@ -34,11 +34,7 @@ obj-$(CONFIG_FAILSLAB) += failslab.o obj-$(CONFIG_MEMORY_HOTPLUG) += memory_hotplug.o obj-$(CONFIG_FS_XIP) += filemap_xip.o obj-$(CONFIG_MIGRATION) += migrate.o -ifndef CONFIG_HAVE_LEGACY_PER_CPU_AREA obj-$(CONFIG_SMP) += percpu.o -else -obj-$(CONFIG_SMP) += allocpercpu.o -endif obj-$(CONFIG_QUICKLIST) += quicklist.o obj-$(CONFIG_CGROUP_MEM_RES_CTLR) += memcontrol.o page_cgroup.o obj-$(CONFIG_MEMORY_FAILURE) += memory-failure.o diff --git a/mm/allocpercpu.c b/mm/allocpercpu.c deleted file mode 100644 index df34ceae0c67..000000000000 --- a/mm/allocpercpu.c +++ /dev/null @@ -1,177 +0,0 @@ -/* - * linux/mm/allocpercpu.c - * - * Separated from slab.c August 11, 2006 Christoph Lameter - */ -#include -#include -#include -#include - -#ifndef cache_line_size -#define cache_line_size() L1_CACHE_BYTES -#endif - -/** - * percpu_depopulate - depopulate per-cpu data for given cpu - * @__pdata: per-cpu data to depopulate - * @cpu: depopulate per-cpu data for this cpu - * - * Depopulating per-cpu data for a cpu going offline would be a typical - * use case. You need to register a cpu hotplug handler for that purpose. - */ -static void percpu_depopulate(void *__pdata, int cpu) -{ - struct percpu_data *pdata = __percpu_disguise(__pdata); - - kfree(pdata->ptrs[cpu]); - pdata->ptrs[cpu] = NULL; -} - -/** - * percpu_depopulate_mask - depopulate per-cpu data for some cpu's - * @__pdata: per-cpu data to depopulate - * @mask: depopulate per-cpu data for cpu's selected through mask bits - */ -static void __percpu_depopulate_mask(void *__pdata, const cpumask_t *mask) -{ - int cpu; - for_each_cpu_mask_nr(cpu, *mask) - percpu_depopulate(__pdata, cpu); -} - -#define percpu_depopulate_mask(__pdata, mask) \ - __percpu_depopulate_mask((__pdata), &(mask)) - -/** - * percpu_populate - populate per-cpu data for given cpu - * @__pdata: per-cpu data to populate further - * @size: size of per-cpu object - * @gfp: may sleep or not etc. - * @cpu: populate per-data for this cpu - * - * Populating per-cpu data for a cpu coming online would be a typical - * use case. You need to register a cpu hotplug handler for that purpose. - * Per-cpu object is populated with zeroed buffer. - */ -static void *percpu_populate(void *__pdata, size_t size, gfp_t gfp, int cpu) -{ - struct percpu_data *pdata = __percpu_disguise(__pdata); - int node = cpu_to_node(cpu); - - /* - * We should make sure each CPU gets private memory. - */ - size = roundup(size, cache_line_size()); - - BUG_ON(pdata->ptrs[cpu]); - if (node_online(node)) - pdata->ptrs[cpu] = kmalloc_node(size, gfp|__GFP_ZERO, node); - else - pdata->ptrs[cpu] = kzalloc(size, gfp); - return pdata->ptrs[cpu]; -} - -/** - * percpu_populate_mask - populate per-cpu data for more cpu's - * @__pdata: per-cpu data to populate further - * @size: size of per-cpu object - * @gfp: may sleep or not etc. - * @mask: populate per-cpu data for cpu's selected through mask bits - * - * Per-cpu objects are populated with zeroed buffers. - */ -static int __percpu_populate_mask(void *__pdata, size_t size, gfp_t gfp, - cpumask_t *mask) -{ - cpumask_t populated; - int cpu; - - cpus_clear(populated); - for_each_cpu_mask_nr(cpu, *mask) - if (unlikely(!percpu_populate(__pdata, size, gfp, cpu))) { - __percpu_depopulate_mask(__pdata, &populated); - return -ENOMEM; - } else - cpu_set(cpu, populated); - return 0; -} - -#define percpu_populate_mask(__pdata, size, gfp, mask) \ - __percpu_populate_mask((__pdata), (size), (gfp), &(mask)) - -/** - * alloc_percpu - initial setup of per-cpu data - * @size: size of per-cpu object - * @align: alignment - * - * Allocate dynamic percpu area. Percpu objects are populated with - * zeroed buffers. - */ -void *__alloc_percpu(size_t size, size_t align) -{ - /* - * We allocate whole cache lines to avoid false sharing - */ - size_t sz = roundup(nr_cpu_ids * sizeof(void *), cache_line_size()); - void *pdata = kzalloc(sz, GFP_KERNEL); - void *__pdata = __percpu_disguise(pdata); - - /* - * Can't easily make larger alignment work with kmalloc. WARN - * on it. Larger alignment should only be used for module - * percpu sections on SMP for which this path isn't used. - */ - WARN_ON_ONCE(align > SMP_CACHE_BYTES); - - if (unlikely(!pdata)) - return NULL; - if (likely(!__percpu_populate_mask(__pdata, size, GFP_KERNEL, - &cpu_possible_map))) - return __pdata; - kfree(pdata); - return NULL; -} -EXPORT_SYMBOL_GPL(__alloc_percpu); - -/** - * free_percpu - final cleanup of per-cpu data - * @__pdata: object to clean up - * - * We simply clean up any per-cpu object left. No need for the client to - * track and specify through a bis mask which per-cpu objects are to free. - */ -void free_percpu(void *__pdata) -{ - if (unlikely(!__pdata)) - return; - __percpu_depopulate_mask(__pdata, cpu_possible_mask); - kfree(__percpu_disguise(__pdata)); -} -EXPORT_SYMBOL_GPL(free_percpu); - -/* - * Generic percpu area setup. - */ -#ifndef CONFIG_HAVE_SETUP_PER_CPU_AREA -unsigned long __per_cpu_offset[NR_CPUS] __read_mostly; - -EXPORT_SYMBOL(__per_cpu_offset); - -void __init setup_per_cpu_areas(void) -{ - unsigned long size, i; - char *ptr; - unsigned long nr_possible_cpus = num_possible_cpus(); - - /* Copy section for each CPU (we discard the original) */ - size = ALIGN(PERCPU_ENOUGH_ROOM, PAGE_SIZE); - ptr = alloc_bootmem_pages(size * nr_possible_cpus); - - for_each_possible_cpu(i) { - __per_cpu_offset[i] = ptr - __per_cpu_start; - memcpy(ptr, __per_cpu_start, __per_cpu_end - __per_cpu_start); - ptr += size; - } -} -#endif /* CONFIG_HAVE_SETUP_PER_CPU_AREA */ diff --git a/mm/percpu.c b/mm/percpu.c index 4a048abad043..e4e08b87b77e 100644 --- a/mm/percpu.c +++ b/mm/percpu.c @@ -46,8 +46,6 @@ * * To use this allocator, arch code should do the followings. * - * - drop CONFIG_HAVE_LEGACY_PER_CPU_AREA - * * - define __addr_to_pcpu_ptr() and __pcpu_ptr_to_addr() to translate * regular address to percpu pointer and back if they need to be * different from the default