Commit 00ae4064 authored by Tejun Heo's avatar Tejun Heo
Browse files

percpu: rename 4k first chunk allocator to page 



Page size isn't always 4k depending on arch and configuration.  Rename
4k first chunk allocator to page.

Signed-off-by: default avatarTejun Heo <tj@kernel.org>
Cc: David Howells <dhowells@redhat.com>
parent 004018e2

Documentation/kernel-parameters.txt

+1 −1
Original line number Diff line number Diff line
@@ -1920,7 +1920,7 @@ and is between 256 and 4096 characters. It is defined in the file 
			See arch/parisc/kernel/pdc_chassis.c



	percpu_alloc=	[X86] Select which percpu first chunk allocator to use.

			Allowed values are one of "lpage", "embed" and "4k".

			Allowed values are one of "lpage", "embed" and "page".

			See comments in arch/x86/kernel/setup_percpu.c for

			details on each allocator.  This parameter is primarily

			for debugging and performance comparison.

arch/x86/kernel/setup_percpu.c

+12 −11
Original line number Diff line number Diff line
@@ -249,21 +249,22 @@ static ssize_t __init setup_pcpu_embed(size_t static_size, bool chosen) 
}



/*

 * 4k allocator

 * Page allocator

 *

 * Boring fallback 4k allocator.  This allocator puts more pressure on

 * PTE TLBs but other than that behaves nicely on both UMA and NUMA.

 * Boring fallback 4k page allocator.  This allocator puts more

 * pressure on PTE TLBs but other than that behaves nicely on both UMA

 * and NUMA.

 */

static void __init pcpu4k_populate_pte(unsigned long addr)

static void __init pcpup_populate_pte(unsigned long addr)

{

	populate_extra_pte(addr);

}



static ssize_t __init setup_pcpu_4k(size_t static_size)

static ssize_t __init setup_pcpu_page(size_t static_size)

{

	return pcpu_4k_first_chunk(static_size, PERCPU_FIRST_CHUNK_RESERVE,

	return pcpu_page_first_chunk(static_size, PERCPU_FIRST_CHUNK_RESERVE,

				     pcpu_fc_alloc, pcpu_fc_free,

				   pcpu4k_populate_pte);

				     pcpup_populate_pte);

}



/* for explicit first chunk allocator selection */
@@ -307,7 +308,7 @@ void __init setup_per_cpu_areas(void) 
	 */

	ret = -EINVAL;

	if (strlen(pcpu_chosen_alloc)) {

		if (strcmp(pcpu_chosen_alloc, "4k")) {

		if (strcmp(pcpu_chosen_alloc, "page")) {

			if (!strcmp(pcpu_chosen_alloc, "lpage"))

				ret = setup_pcpu_lpage(static_size, true);

			else if (!strcmp(pcpu_chosen_alloc, "embed"))
@@ -317,7 +318,7 @@ void __init setup_per_cpu_areas(void) 
					   "specified\n", pcpu_chosen_alloc);

			if (ret < 0)

				pr_warning("PERCPU: %s allocator failed (%zd), "

					   "falling back to 4k\n",

					   "falling back to page size\n",

					   pcpu_chosen_alloc, ret);

		}

	} else {
@@ -326,7 +327,7 @@ void __init setup_per_cpu_areas(void) 
			ret = setup_pcpu_embed(static_size, false);

	}

	if (ret < 0)

		ret = setup_pcpu_4k(static_size);

		ret = setup_pcpu_page(static_size);

	if (ret < 0)

		panic("cannot allocate static percpu area (%zu bytes, err=%zd)",

		      static_size, ret);

include/linux/percpu.h

+1 −1
Original line number Diff line number Diff line
@@ -74,7 +74,7 @@ extern ssize_t __init pcpu_embed_first_chunk( 
				size_t static_size, size_t reserved_size,

				ssize_t dyn_size);



extern ssize_t __init pcpu_4k_first_chunk(

extern ssize_t __init pcpu_page_first_chunk(

				size_t static_size, size_t reserved_size,

				pcpu_fc_alloc_fn_t alloc_fn,

				pcpu_fc_free_fn_t free_fn,

mm/percpu.c

+14 −11
Original line number Diff line number Diff line
@@ -1497,15 +1497,15 @@ ssize_t __init pcpu_embed_first_chunk(size_t static_size, size_t reserved_size, 
}



/**

 * pcpu_4k_first_chunk - map the first chunk using PAGE_SIZE pages

 * pcpu_page_first_chunk - map the first chunk using PAGE_SIZE pages

 * @static_size: the size of static percpu area in bytes

 * @reserved_size: the size of reserved percpu area in bytes

 * @alloc_fn: function to allocate percpu page, always called with PAGE_SIZE

 * @free_fn: funtion to free percpu page, always called with PAGE_SIZE

 * @populate_pte_fn: function to populate pte

 *

 * This is a helper to ease setting up embedded first percpu chunk and

 * can be called where pcpu_setup_first_chunk() is expected.

 * This is a helper to ease setting up page-remapped first percpu

 * chunk and can be called where pcpu_setup_first_chunk() is expected.

 *

 * This is the basic allocator.  Static percpu area is allocated

 * page-by-page into vmalloc area.
@@ -1514,12 +1514,13 @@ ssize_t __init pcpu_embed_first_chunk(size_t static_size, size_t reserved_size, 
 * The determined pcpu_unit_size which can be used to initialize

 * percpu access on success, -errno on failure.

 */

ssize_t __init pcpu_4k_first_chunk(size_t static_size, size_t reserved_size,

ssize_t __init pcpu_page_first_chunk(size_t static_size, size_t reserved_size,

				     pcpu_fc_alloc_fn_t alloc_fn,

				     pcpu_fc_free_fn_t free_fn,

				     pcpu_fc_populate_pte_fn_t populate_pte_fn)

{

	static struct vm_struct vm;

	char psize_str[16];

	int unit_pages;

	size_t pages_size;

	struct page **pages;
@@ -1527,6 +1528,8 @@ ssize_t __init pcpu_4k_first_chunk(size_t static_size, size_t reserved_size, 
	int i, j;

	ssize_t ret;



	snprintf(psize_str, sizeof(psize_str), "%luK", PAGE_SIZE >> 10);



	unit_pages = PFN_UP(max_t(size_t, static_size + reserved_size,

				  PCPU_MIN_UNIT_SIZE));
@@ -1542,8 +1545,8 @@ ssize_t __init pcpu_4k_first_chunk(size_t static_size, size_t reserved_size, 


			ptr = alloc_fn(cpu, PAGE_SIZE);

			if (!ptr) {

				pr_warning("PERCPU: failed to allocate "

					   "4k page for cpu%u\n", cpu);

				pr_warning("PERCPU: failed to allocate %s page "

					   "for cpu%u\n", psize_str, cpu);

				goto enomem;

			}

			pages[j++] = virt_to_page(ptr);
@@ -1580,8 +1583,8 @@ ssize_t __init pcpu_4k_first_chunk(size_t static_size, size_t reserved_size, 
	}



	/* we're ready, commit */

	pr_info("PERCPU: %d 4k pages/cpu @%p s%zu r%zu\n",

		unit_pages, vm.addr, static_size, reserved_size);

	pr_info("PERCPU: %d %s pages/cpu @%p s%zu r%zu\n",

		unit_pages, psize_str, vm.addr, static_size, reserved_size);



	ret = pcpu_setup_first_chunk(static_size, reserved_size, -1,

				     unit_pages << PAGE_SHIFT, vm.addr, NULL);