diff options
Diffstat (limited to 'arch/x86/kernel/setup_percpu.c')
| -rw-r--r-- | arch/x86/kernel/setup_percpu.c | 37 |
1 files changed, 28 insertions, 9 deletions
diff --git a/arch/x86/kernel/setup_percpu.c b/arch/x86/kernel/setup_percpu.c index dd4eabc..efa615f 100644 --- a/arch/x86/kernel/setup_percpu.c +++ b/arch/x86/kernel/setup_percpu.c @@ -42,6 +42,19 @@ unsigned long __per_cpu_offset[NR_CPUS] __read_mostly = { }; EXPORT_SYMBOL(__per_cpu_offset); +/* + * On x86_64 symbols referenced from code should be reachable using + * 32bit relocations. Reserve space for static percpu variables in + * modules so that they are always served from the first chunk which + * is located at the percpu segment base. On x86_32, anything can + * address anywhere. No need to reserve space in the first chunk. + */ +#ifdef CONFIG_X86_64 +#define PERCPU_FIRST_CHUNK_RESERVE PERCPU_MODULE_RESERVE +#else +#define PERCPU_FIRST_CHUNK_RESERVE 0 +#endif + /** * pcpu_need_numa - determine percpu allocation needs to consider NUMA * @@ -141,7 +154,7 @@ static ssize_t __init setup_pcpu_remap(size_t static_size) { static struct vm_struct vm; pg_data_t *last; - size_t ptrs_size; + size_t ptrs_size, dyn_size; unsigned int cpu; ssize_t ret; @@ -169,12 +182,14 @@ proceed: * Currently supports only single page. Supporting multiple * pages won't be too difficult if it ever becomes necessary. */ - pcpur_size = PFN_ALIGN(static_size + PERCPU_DYNAMIC_RESERVE); + pcpur_size = PFN_ALIGN(static_size + PERCPU_MODULE_RESERVE + + PERCPU_DYNAMIC_RESERVE); if (pcpur_size > PMD_SIZE) { pr_warning("PERCPU: static data is larger than large page, " "can't use large page\n"); return -EINVAL; } + dyn_size = pcpur_size - static_size - PERCPU_FIRST_CHUNK_RESERVE; /* allocate pointer array and alloc large pages */ ptrs_size = PFN_ALIGN(num_possible_cpus() * sizeof(pcpur_ptrs[0])); @@ -217,8 +232,9 @@ proceed: pr_info("PERCPU: Remapped at %p with large pages, static data " "%zu bytes\n", vm.addr, static_size); - ret = pcpu_setup_first_chunk(pcpur_get_page, static_size, 0, PMD_SIZE, - pcpur_size - static_size, vm.addr, NULL); + ret = pcpu_setup_first_chunk(pcpur_get_page, static_size, + PERCPU_FIRST_CHUNK_RESERVE, + PMD_SIZE, dyn_size, vm.addr, NULL); goto out_free_ar; enomem: @@ -276,9 +292,10 @@ static ssize_t __init setup_pcpu_embed(size_t static_size) return -EINVAL; /* allocate and copy */ - pcpue_size = PFN_ALIGN(static_size + PERCPU_DYNAMIC_RESERVE); + pcpue_size = PFN_ALIGN(static_size + PERCPU_MODULE_RESERVE + + PERCPU_DYNAMIC_RESERVE); pcpue_unit_size = max_t(size_t, pcpue_size, PCPU_MIN_UNIT_SIZE); - dyn_size = pcpue_size - static_size; + dyn_size = pcpue_size - static_size - PERCPU_FIRST_CHUNK_RESERVE; pcpue_ptr = pcpu_alloc_bootmem(0, num_possible_cpus() * pcpue_unit_size, PAGE_SIZE); @@ -297,7 +314,8 @@ static ssize_t __init setup_pcpu_embed(size_t static_size) pr_info("PERCPU: Embedded %zu pages at %p, static data %zu bytes\n", pcpue_size >> PAGE_SHIFT, pcpue_ptr, static_size); - return pcpu_setup_first_chunk(pcpue_get_page, static_size, 0, + return pcpu_setup_first_chunk(pcpue_get_page, static_size, + PERCPU_FIRST_CHUNK_RESERVE, pcpue_unit_size, dyn_size, pcpue_ptr, NULL); } @@ -356,8 +374,9 @@ static ssize_t __init setup_pcpu_4k(size_t static_size) 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, -1, -1, - NULL, pcpu4k_populate_pte); + ret = pcpu_setup_first_chunk(pcpu4k_get_page, static_size, + PERCPU_FIRST_CHUNK_RESERVE, -1, -1, NULL, + pcpu4k_populate_pte); goto out_free_ar; enomem: |