[PATCH 03/20] percpu: rename 4k first chunk allocator to page

Tejun Heo
2009-07-21T10:28:05Z

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

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: David Howells <dhowells@redhat.com>
---
Documentation/kernel-parameters.txt | 2 +-
arch/x86/kernel/setup_percpu.c | 23 ++++++++++++-----------
include/linux/percpu.h | 2 +-
mm/percpu.c | 25 ++++++++++++++-----------
4 files changed, 28 insertions(+), 24 deletions(-)

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index dd1a6d4..faa7178 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1916,7 +1916,7 @@ 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.
diff --git a/arch/x86/kernel/setup_percpu.c b/arch/x86/kernel/setup_percpu.c
index 7501bb1..3c943b4 100644
--- a/arch/x86/kernel/setup_percpu.c
+++ b/arch/x86/kernel/setup_percpu.c
@@ -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,
- pcpu_fc_alloc, pcpu_fc_free,
- pcpu4k_populate_pte);
+ return pcpu_page_first_chunk(static_size, PERCPU_FIRST_CHUNK_RESERVE,
+ pcpu_fc_alloc, pcpu_fc_free,
+ 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\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);
diff --git a/include/linux/percpu.h b/include/linux/percpu.h
index e134c82..7989f61 100644
--- a/include/linux/percpu.h
+++ b/include/linux/percpu.h
@@ -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,
diff --git a/mm/percpu.c b/mm/percpu.c
index 80317dc..27a3033 100644
--- a/mm/percpu.c
+++ b/mm/percpu.c
@@ -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,
- pcpu_fc_alloc_fn_t alloc_fn,
- pcpu_fc_free_fn_t free_fn,
- pcpu_fc_populate_pte_fn_t populate_pte_fn)
+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);
--
1.6.0.2