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Commit 11124411 authored by Tejun Heo's avatar Tejun Heo
Browse files

x86: convert to the new dynamic percpu allocator 



Impact: use new dynamic allocator, unified access to static/dynamic
        percpu memory

Convert to the new dynamic percpu allocator.

* implement populate_extra_pte() for both 32 and 64
* update setup_per_cpu_areas() to use pcpu_setup_static()
* define __addr_to_pcpu_ptr() and __pcpu_ptr_to_addr()
* define config HAVE_DYNAMIC_PER_CPU_AREA

Signed-off-by: default avatarTejun Heo <tj@kernel.org>
parent fbf59bc9

arch/x86/Kconfig

+3 −0
Original line number Diff line number Diff line
@@ -135,6 +135,9 @@ config ARCH_HAS_CACHE_LINE_SIZE 
config HAVE_SETUP_PER_CPU_AREA

	def_bool y



config HAVE_DYNAMIC_PER_CPU_AREA

	def_bool y



config HAVE_CPUMASK_OF_CPU_MAP

	def_bool X86_64_SMP

arch/x86/include/asm/percpu.h

+8 −0
Original line number Diff line number Diff line
@@ -43,6 +43,14 @@ 
#else /* ...!ASSEMBLY */



#include <linux/stringify.h>

#include <asm/sections.h>



#define __addr_to_pcpu_ptr(addr)					\

	(void *)((unsigned long)(addr) - (unsigned long)pcpu_base_addr	\

		 + (unsigned long)__per_cpu_start)

#define __pcpu_ptr_to_addr(ptr)						\

	(void *)((unsigned long)(ptr) + (unsigned long)pcpu_base_addr	\

		 - (unsigned long)__per_cpu_start)



#ifdef CONFIG_SMP

#define __percpu_arg(x)		"%%"__stringify(__percpu_seg)":%P" #x

arch/x86/include/asm/pgtable.h

+1 −0
Original line number Diff line number Diff line
@@ -402,6 +402,7 @@ int phys_mem_access_prot_allowed(struct file *file, unsigned long pfn, 


/* Install a pte for a particular vaddr in kernel space. */

void set_pte_vaddr(unsigned long vaddr, pte_t pte);

void populate_extra_pte(unsigned long vaddr);



#ifdef CONFIG_X86_32

extern void native_pagetable_setup_start(pgd_t *base);

arch/x86/kernel/setup_percpu.c

+40 −22
Original line number Diff line number Diff line
@@ -61,38 +61,56 @@ static inline void setup_percpu_segment(int cpu) 
 */

void __init setup_per_cpu_areas(void)

{

	ssize_t size;

	char *ptr;

	int cpu;



	/* Copy section for each CPU (we discard the original) */

	size = roundup(PERCPU_ENOUGH_ROOM, PAGE_SIZE);

	ssize_t size = __per_cpu_end - __per_cpu_start;

	unsigned int nr_cpu_pages = DIV_ROUND_UP(size, PAGE_SIZE);

	static struct page **pages;

	size_t pages_size;

	unsigned int cpu, i, j;

	unsigned long delta;

	size_t pcpu_unit_size;



	pr_info("NR_CPUS:%d nr_cpumask_bits:%d nr_cpu_ids:%d nr_node_ids:%d\n",

		NR_CPUS, nr_cpumask_bits, nr_cpu_ids, nr_node_ids);

	pr_info("PERCPU: Allocating %zd bytes for static per cpu data\n", size);



	pr_info("PERCPU: Allocating %zd bytes of per cpu data\n", size);

	pages_size = nr_cpu_pages * num_possible_cpus() * sizeof(pages[0]);

	pages = alloc_bootmem(pages_size);



	j = 0;

	for_each_possible_cpu(cpu) {

		void *ptr;



		for (i = 0; i < nr_cpu_pages; i++) {

#ifndef CONFIG_NEED_MULTIPLE_NODES

		ptr = alloc_bootmem_pages(size);

			ptr = alloc_bootmem_pages(PAGE_SIZE);

#else

			int node = early_cpu_to_node(cpu);



			if (!node_online(node) || !NODE_DATA(node)) {

			ptr = alloc_bootmem_pages(size);

			pr_info("cpu %d has no node %d or node-local memory\n",

				cpu, node);

				ptr = alloc_bootmem_pages(PAGE_SIZE);

				pr_info("cpu %d has no node %d or node-local "

					"memory\n", cpu, node);

				pr_debug("per cpu data for cpu%d at %016lx\n",

					 cpu, __pa(ptr));

			} else {

			ptr = alloc_bootmem_pages_node(NODE_DATA(node), size);

			pr_debug("per cpu data for cpu%d on node%d at %016lx\n",

				cpu, node, __pa(ptr));

				ptr = alloc_bootmem_pages_node(NODE_DATA(node),

							       PAGE_SIZE);

				pr_debug("per cpu data for cpu%d on node%d "

					 "at %016lx\n", cpu, node, __pa(ptr));

			}

#endif

			memcpy(ptr, __per_cpu_load + i * PAGE_SIZE, PAGE_SIZE);

			pages[j++] = virt_to_page(ptr);

		}

	}



	pcpu_unit_size = pcpu_setup_static(populate_extra_pte, pages, size);



		memcpy(ptr, __per_cpu_load, __per_cpu_end - __per_cpu_start);

		per_cpu_offset(cpu) = ptr - __per_cpu_start;

	free_bootmem(__pa(pages), pages_size);



	delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start;

	for_each_possible_cpu(cpu) {

		per_cpu_offset(cpu) = delta + cpu * pcpu_unit_size;

		per_cpu(this_cpu_off, cpu) = per_cpu_offset(cpu);

		per_cpu(cpu_number, cpu) = cpu;

		setup_percpu_segment(cpu);

arch/x86/mm/init_32.c

+10 −0
Original line number Diff line number Diff line
@@ -137,6 +137,16 @@ static pte_t * __init one_page_table_init(pmd_t *pmd) 
	return pte_offset_kernel(pmd, 0);

}



void __init populate_extra_pte(unsigned long vaddr)

{

	int pgd_idx = pgd_index(vaddr);

	int pmd_idx = pmd_index(vaddr);

	pmd_t *pmd;



	pmd = one_md_table_init(swapper_pg_dir + pgd_idx);

	one_page_table_init(pmd + pmd_idx);

}



static pte_t *__init page_table_kmap_check(pte_t *pte, pmd_t *pmd,

					   unsigned long vaddr, pte_t *lastpte)

{