Commit 5f5d8405 authored by Tejun Heo's avatar Tejun Heo

x86: separate out setup_pcpu_4k() from setup_per_cpu_areas()

Impact: modularize percpu first chunk allocation

x86 is gonna have a few different strategies for the first chunk
allocation.  Modularize it by separating out the current allocation
mechanism into pcpu_alloc_bootmem() and setup_pcpu_4k().
Signed-off-by: default avatarTejun Heo <tj@kernel.org>
parent 8d408b4b
...@@ -7,6 +7,7 @@ ...@@ -7,6 +7,7 @@
#include <linux/crash_dump.h> #include <linux/crash_dump.h>
#include <linux/smp.h> #include <linux/smp.h>
#include <linux/topology.h> #include <linux/topology.h>
#include <linux/pfn.h>
#include <asm/sections.h> #include <asm/sections.h>
#include <asm/processor.h> #include <asm/processor.h>
#include <asm/setup.h> #include <asm/setup.h>
...@@ -41,6 +42,52 @@ unsigned long __per_cpu_offset[NR_CPUS] __read_mostly = { ...@@ -41,6 +42,52 @@ unsigned long __per_cpu_offset[NR_CPUS] __read_mostly = {
}; };
EXPORT_SYMBOL(__per_cpu_offset); EXPORT_SYMBOL(__per_cpu_offset);
/**
* pcpu_alloc_bootmem - NUMA friendly alloc_bootmem wrapper for percpu
* @cpu: cpu to allocate for
* @size: size allocation in bytes
* @align: alignment
*
* Allocate @size bytes aligned at @align for cpu @cpu. This wrapper
* does the right thing for NUMA regardless of the current
* configuration.
*
* RETURNS:
* Pointer to the allocated area on success, NULL on failure.
*/
static void * __init pcpu_alloc_bootmem(unsigned int cpu, unsigned long size,
unsigned long align)
{
const unsigned long goal = __pa(MAX_DMA_ADDRESS);
#ifdef CONFIG_NEED_MULTIPLE_NODES
int node = early_cpu_to_node(cpu);
void *ptr;
if (!node_online(node) || !NODE_DATA(node)) {
ptr = __alloc_bootmem_nopanic(size, align, goal);
pr_info("cpu %d has no node %d or node-local memory\n",
cpu, node);
pr_debug("per cpu data for cpu%d %lu bytes at %016lx\n",
cpu, size, __pa(ptr));
} else {
ptr = __alloc_bootmem_node_nopanic(NODE_DATA(node),
size, align, goal);
pr_debug("per cpu data for cpu%d %lu bytes on node%d at "
"%016lx\n", cpu, size, node, __pa(ptr));
}
return ptr;
#else
return __alloc_bootmem_nopanic(size, align, goal);
#endif
}
/*
* 4k page allocator
*
* This is the basic allocator. Static percpu area is allocated
* page-by-page and most of initialization is done by the generic
* setup function.
*/
static struct page **pcpu4k_pages __initdata; static struct page **pcpu4k_pages __initdata;
static int pcpu4k_nr_static_pages __initdata; static int pcpu4k_nr_static_pages __initdata;
...@@ -56,6 +103,51 @@ static void __init pcpu4k_populate_pte(unsigned long addr) ...@@ -56,6 +103,51 @@ static void __init pcpu4k_populate_pte(unsigned long addr)
populate_extra_pte(addr); populate_extra_pte(addr);
} }
static ssize_t __init setup_pcpu_4k(size_t static_size)
{
size_t pages_size;
unsigned int cpu;
int i, j;
ssize_t ret;
pcpu4k_nr_static_pages = PFN_UP(static_size);
/* unaligned allocations can't be freed, round up to page size */
pages_size = PFN_ALIGN(pcpu4k_nr_static_pages * num_possible_cpus()
* sizeof(pcpu4k_pages[0]));
pcpu4k_pages = alloc_bootmem(pages_size);
/* allocate and copy */
j = 0;
for_each_possible_cpu(cpu)
for (i = 0; i < pcpu4k_nr_static_pages; i++) {
void *ptr;
ptr = pcpu_alloc_bootmem(cpu, PAGE_SIZE, PAGE_SIZE);
if (!ptr)
goto enomem;
memcpy(ptr, __per_cpu_load + i * PAGE_SIZE, PAGE_SIZE);
pcpu4k_pages[j++] = virt_to_page(ptr);
}
/* we're ready, commit */
pr_info("PERCPU: Allocated %d 4k pages, static data %zu bytes\n",
pcpu4k_nr_static_pages, static_size);
ret = pcpu_setup_first_chunk(pcpu4k_get_page, static_size, 0, 0, NULL,
pcpu4k_populate_pte);
goto out_free_ar;
enomem:
while (--j >= 0)
free_bootmem(__pa(page_address(pcpu4k_pages[j])), PAGE_SIZE);
ret = -ENOMEM;
out_free_ar:
free_bootmem(__pa(pcpu4k_pages), pages_size);
return ret;
}
static inline void setup_percpu_segment(int cpu) static inline void setup_percpu_segment(int cpu)
{ {
#ifdef CONFIG_X86_32 #ifdef CONFIG_X86_32
...@@ -76,56 +168,24 @@ static inline void setup_percpu_segment(int cpu) ...@@ -76,56 +168,24 @@ static inline void setup_percpu_segment(int cpu)
*/ */
void __init setup_per_cpu_areas(void) void __init setup_per_cpu_areas(void)
{ {
ssize_t size = __per_cpu_end - __per_cpu_start; size_t static_size = __per_cpu_end - __per_cpu_start;
unsigned int nr_cpu_pages = DIV_ROUND_UP(size, PAGE_SIZE); unsigned int cpu;
static struct page **pages;
size_t pages_size;
unsigned int cpu, i, j;
unsigned long delta; unsigned long delta;
size_t pcpu_unit_size; size_t pcpu_unit_size;
ssize_t ret;
pr_info("NR_CPUS:%d nr_cpumask_bits:%d nr_cpu_ids:%d nr_node_ids:%d\n", 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); NR_CPUS, nr_cpumask_bits, nr_cpu_ids, nr_node_ids);
pr_info("PERCPU: Allocating %zd bytes for static 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(PAGE_SIZE);
#else
int node = early_cpu_to_node(cpu);
if (!node_online(node) || !NODE_DATA(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),
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);
}
}
pcpu4k_pages = pages; /* allocate percpu area */
pcpu4k_nr_static_pages = nr_cpu_pages; ret = setup_pcpu_4k(static_size);
pcpu_unit_size = pcpu_setup_first_chunk(pcpu4k_get_page, size, 0, 0, if (ret < 0)
NULL, pcpu4k_populate_pte); panic("cannot allocate static percpu area (%zu bytes, err=%zd)",
static_size, ret);
free_bootmem(__pa(pages), pages_size); pcpu_unit_size = ret;
/* alrighty, percpu areas up and running */
delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start; delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start;
for_each_possible_cpu(cpu) { for_each_possible_cpu(cpu) {
per_cpu_offset(cpu) = delta + cpu * pcpu_unit_size; per_cpu_offset(cpu) = delta + cpu * pcpu_unit_size;
......
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