[PATCH 1/4] x86: prepare setup_pcpu_remap() for pageattr fix

Tejun Heo
2009-05-14T12:51:06Z

Make the following changes in preparation of coming pageattr updates.

* Define and use array of struct pcpur_ent instead of array of
pointers. The only difference is ->cpu field which is set but
unused yet.

* Rename variables according to the above change.

* Rename local variable vm to pcpur_vm and move it out of the
function.

[ Impact: no functional difference ]

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jan Beulich <JBeulich@novell.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ingo Molnar <mingo@elte.hu>
---
arch/x86/kernel/setup_percpu.c | 58 ++++++++++++++++++++++-----------------
1 files changed, 33 insertions(+), 25 deletions(-)

diff --git a/arch/x86/kernel/setup_percpu.c b/arch/x86/kernel/setup_percpu.c
index 3a97a4c..c17059c 100644
--- a/arch/x86/kernel/setup_percpu.c
+++ b/arch/x86/kernel/setup_percpu.c
@@ -137,8 +137,14 @@ static void * __init pcpu_alloc_bootmem(unsigned int cpu, unsigned long size,
* better than only using 4k mappings while still being NUMA friendly.
*/
#ifdef CONFIG_NEED_MULTIPLE_NODES
+struct pcpur_ent {
+ unsigned int cpu;
+ void *ptr;
+};
+
static size_t pcpur_size __initdata;
-static void **pcpur_ptrs __initdata;
+static struct pcpur_ent *pcpur_map __initdata;
+static struct vm_struct pcpur_vm;

static struct page * __init pcpur_get_page(unsigned int cpu, int pageno)
{
@@ -147,13 +153,12 @@ static struct page * __init pcpur_get_page(unsigned int cpu, int pageno)
if (off >= pcpur_size)
return NULL;

- return virt_to_page(pcpur_ptrs[cpu] + off);
+ return virt_to_page(pcpur_map[cpu].ptr + off);
}

static ssize_t __init setup_pcpu_remap(size_t static_size)
{
- static struct vm_struct vm;
- size_t ptrs_size, dyn_size;
+ size_t map_size, dyn_size;
unsigned int cpu;
ssize_t ret;

@@ -178,12 +183,14 @@ static ssize_t __init setup_pcpu_remap(size_t static_size)
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]));
- pcpur_ptrs = alloc_bootmem(ptrs_size);
+ map_size = PFN_ALIGN(num_possible_cpus() * sizeof(pcpur_map[0]));
+ pcpur_map = alloc_bootmem(map_size);

for_each_possible_cpu(cpu) {
- pcpur_ptrs[cpu] = pcpu_alloc_bootmem(cpu, PMD_SIZE, PMD_SIZE);
- if (!pcpur_ptrs[cpu])
+ pcpur_map[cpu].cpu = cpu;
+ pcpur_map[cpu].ptr = pcpu_alloc_bootmem(cpu, PMD_SIZE,
+ PMD_SIZE);
+ if (!pcpur_map[cpu].ptr)
goto enomem;

/*
@@ -194,42 +201,43 @@ static ssize_t __init setup_pcpu_remap(size_t static_size)
* not well-specified to have a PAT-incompatible area
* (unmapped RAM, device memory, etc.) in that hole.
*/
- free_bootmem(__pa(pcpur_ptrs[cpu] + pcpur_size),
+ free_bootmem(__pa(pcpur_map[cpu].ptr + pcpur_size),
PMD_SIZE - pcpur_size);

- memcpy(pcpur_ptrs[cpu], __per_cpu_load, static_size);
+ memcpy(pcpur_map[cpu].ptr, __per_cpu_load, static_size);
}

/* allocate address and map */
- vm.flags = VM_ALLOC;
- vm.size = num_possible_cpus() * PMD_SIZE;
- vm_area_register_early(&vm, PMD_SIZE);
+ pcpur_vm.flags = VM_ALLOC;
+ pcpur_vm.size = num_possible_cpus() * PMD_SIZE;
+ vm_area_register_early(&pcpur_vm, PMD_SIZE);

for_each_possible_cpu(cpu) {
- pmd_t *pmd;
+ pmd_t *pmd, pmd_v;

- pmd = populate_extra_pmd((unsigned long)vm.addr
- + cpu * PMD_SIZE);
- set_pmd(pmd, pfn_pmd(page_to_pfn(virt_to_page(pcpur_ptrs[cpu])),
- PAGE_KERNEL_LARGE));
+ pmd = populate_extra_pmd((unsigned long)pcpur_vm.addr +
+ cpu * PMD_SIZE);
+ pmd_v = pfn_pmd(page_to_pfn(virt_to_page(pcpur_map[cpu].ptr)),
+ PAGE_KERNEL_LARGE);
+ set_pmd(pmd, pmd_v);
}

/* we're ready, commit */
pr_info("PERCPU: Remapped at %p with large pages, static data "
- "%zu bytes\n", vm.addr, static_size);
+ "%zu bytes\n", pcpur_vm.addr, static_size);

ret = pcpu_setup_first_chunk(pcpur_get_page, static_size,
PERCPU_FIRST_CHUNK_RESERVE, dyn_size,
- PMD_SIZE, vm.addr, NULL);
- goto out_free_ar;
+ PMD_SIZE, pcpur_vm.addr, NULL);
+ goto out_free_map;

enomem:
for_each_possible_cpu(cpu)
- if (pcpur_ptrs[cpu])
- free_bootmem(__pa(pcpur_ptrs[cpu]), PMD_SIZE);
+ if (pcpur_map[cpu].ptr)
+ free_bootmem(__pa(pcpur_map[cpu].ptr), PMD_SIZE);
ret = -ENOMEM;
-out_free_ar:
- free_bootmem(__pa(pcpur_ptrs), ptrs_size);
+out_free_map:
+ free_bootmem(__pa(pcpur_map), map_size);
return ret;
}
#else
--
1.6.0.2