[PATCH 06/20] percpu: drop @static_size from first chunk allocators

Tejun Heo
2009-07-21T10:26:05Z

First chunk allocators assume percpu areas have been linked using one
of PERCPU_*() macros and depend on __per_cpu_load symbol defined by
those macros, so there isn't much point in passing in static area size
explicitly when it can be easily calculated from __per_cpu_start and
__per_cpu_end. Drop @static_size from all percpu first chunk
allocators and helpers.

Signed-off-by: Tejun Heo <tj@kernel.org>
---
arch/x86/kernel/setup_percpu.c | 34 +++++++++++++++-------------------
include/linux/percpu.h | 18 ++++++++----------
mm/percpu.c | 29 +++++++++++++----------------
3 files changed, 36 insertions(+), 45 deletions(-)

diff --git a/arch/x86/kernel/setup_percpu.c b/arch/x86/kernel/setup_percpu.c
index 7f1e09b..b0e7ac4 100644
--- a/arch/x86/kernel/setup_percpu.c
+++ b/arch/x86/kernel/setup_percpu.c
@@ -157,7 +157,7 @@ static int pcpu_lpage_cpu_distance(unsigned int from, unsigned int to)
return REMOTE_DISTANCE;
}

-static ssize_t __init setup_pcpu_lpage(size_t static_size, bool chosen)
+static ssize_t __init setup_pcpu_lpage(bool chosen)
{
size_t reserve = PERCPU_MODULE_RESERVE + PERCPU_DYNAMIC_RESERVE;
size_t dyn_size = reserve - PERCPU_FIRST_CHUNK_RESERVE;
@@ -184,8 +184,7 @@ static ssize_t __init setup_pcpu_lpage(size_t static_size, bool chosen)
return -ENOMEM;
}

- ret = pcpu_lpage_build_unit_map(static_size,
- PERCPU_FIRST_CHUNK_RESERVE,
+ ret = pcpu_lpage_build_unit_map(PERCPU_FIRST_CHUNK_RESERVE,
&dyn_size, &unit_size, PMD_SIZE,
unit_map, pcpu_lpage_cpu_distance);
if (ret < 0) {
@@ -208,9 +207,8 @@ static ssize_t __init setup_pcpu_lpage(size_t static_size, bool chosen)
}
}

- ret = pcpu_lpage_first_chunk(static_size, PERCPU_FIRST_CHUNK_RESERVE,
- dyn_size, unit_size, PMD_SIZE,
- unit_map, nr_units,
+ ret = pcpu_lpage_first_chunk(PERCPU_FIRST_CHUNK_RESERVE, dyn_size,
+ unit_size, PMD_SIZE, unit_map, nr_units,
pcpu_fc_alloc, pcpu_fc_free, pcpul_map);
out_free:
if (ret < 0)
@@ -218,7 +216,7 @@ out_free:
return ret;
}
#else
-static ssize_t __init setup_pcpu_lpage(size_t static_size, bool chosen)
+static ssize_t __init setup_pcpu_lpage(bool chosen)
{
return -EINVAL;
}
@@ -232,7 +230,7 @@ static ssize_t __init setup_pcpu_lpage(size_t static_size, bool chosen)
* mapping so that it can use PMD mapping without additional TLB
* pressure.
*/
-static ssize_t __init setup_pcpu_embed(size_t static_size, bool chosen)
+static ssize_t __init setup_pcpu_embed(bool chosen)
{
size_t reserve = PERCPU_MODULE_RESERVE + PERCPU_DYNAMIC_RESERVE;

@@ -244,7 +242,7 @@ static ssize_t __init setup_pcpu_embed(size_t static_size, bool chosen)
if (!chosen && (!cpu_has_pse || pcpu_need_numa()))
return -EINVAL;

- return pcpu_embed_first_chunk(static_size, PERCPU_FIRST_CHUNK_RESERVE,
+ return pcpu_embed_first_chunk(PERCPU_FIRST_CHUNK_RESERVE,
reserve - PERCPU_FIRST_CHUNK_RESERVE);
}

@@ -260,9 +258,9 @@ static void __init pcpup_populate_pte(unsigned long addr)
populate_extra_pte(addr);
}

-static ssize_t __init setup_pcpu_page(size_t static_size)
+static ssize_t __init setup_pcpu_page(void)
{
- return pcpu_page_first_chunk(static_size, PERCPU_FIRST_CHUNK_RESERVE,
+ return pcpu_page_first_chunk(PERCPU_FIRST_CHUNK_RESERVE,
pcpu_fc_alloc, pcpu_fc_free,
pcpup_populate_pte);
}
@@ -282,7 +280,6 @@ static inline void setup_percpu_segment(int cpu)

void __init setup_per_cpu_areas(void)
{
- size_t static_size = __per_cpu_end - __per_cpu_start;
unsigned int cpu;
unsigned long delta;
size_t pcpu_unit_size;
@@ -300,9 +297,9 @@ void __init setup_per_cpu_areas(void)
if (pcpu_chosen_fc != PCPU_FC_AUTO) {
if (pcpu_chosen_fc != PCPU_FC_PAGE) {
if (pcpu_chosen_fc == PCPU_FC_LPAGE)
- ret = setup_pcpu_lpage(static_size, true);
+ ret = setup_pcpu_lpage(true);
else
- ret = setup_pcpu_embed(static_size, true);
+ ret = setup_pcpu_embed(true);

if (ret < 0)
pr_warning("PERCPU: %s allocator failed (%zd), "
@@ -310,15 +307,14 @@ void __init setup_per_cpu_areas(void)
pcpu_fc_names[pcpu_chosen_fc], ret);
}
} else {
- ret = setup_pcpu_lpage(static_size, false);
+ ret = setup_pcpu_lpage(false);
if (ret < 0)
- ret = setup_pcpu_embed(static_size, false);
+ ret = setup_pcpu_embed(false);
}
if (ret < 0)
- ret = setup_pcpu_page(static_size);
+ ret = setup_pcpu_page();
if (ret < 0)
- panic("cannot allocate static percpu area (%zu bytes, err=%zd)",
- static_size, ret);
+ panic("cannot initialize percpu area (err=%zd)", ret);

pcpu_unit_size = ret;

diff --git a/include/linux/percpu.h b/include/linux/percpu.h
index 9be05cb..be2fc8f 100644
--- a/include/linux/percpu.h
+++ b/include/linux/percpu.h
@@ -84,13 +84,12 @@ extern size_t __init pcpu_setup_first_chunk(

#ifdef CONFIG_NEED_PER_CPU_EMBED_FIRST_CHUNK
extern ssize_t __init pcpu_embed_first_chunk(
- size_t static_size, size_t reserved_size,
- ssize_t dyn_size);
+ size_t reserved_size, ssize_t dyn_size);
#endif

#ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK
extern ssize_t __init pcpu_page_first_chunk(
- size_t static_size, size_t reserved_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);
@@ -98,16 +97,15 @@ extern ssize_t __init pcpu_page_first_chunk(

#ifdef CONFIG_NEED_PER_CPU_LPAGE_FIRST_CHUNK
extern int __init pcpu_lpage_build_unit_map(
- size_t static_size, size_t reserved_size,
- ssize_t *dyn_sizep, size_t *unit_sizep,
- size_t lpage_size, int *unit_map,
+ size_t reserved_size, ssize_t *dyn_sizep,
+ size_t *unit_sizep, size_t lpage_size,
+ int *unit_map,
pcpu_fc_cpu_distance_fn_t cpu_distance_fn);

extern ssize_t __init pcpu_lpage_first_chunk(
- size_t static_size, size_t reserved_size,
- size_t dyn_size, size_t unit_size,
- size_t lpage_size, const int *unit_map,
- int nr_units,
+ size_t reserved_size, size_t dyn_size,
+ size_t unit_size, size_t lpage_size,
+ const int *unit_map, int nr_units,
pcpu_fc_alloc_fn_t alloc_fn,
pcpu_fc_free_fn_t free_fn,
pcpu_fc_map_fn_t map_fn);
diff --git a/mm/percpu.c b/mm/percpu.c
index 6617020..e9f45ab 100644
--- a/mm/percpu.c
+++ b/mm/percpu.c
@@ -1464,7 +1464,6 @@ static inline size_t pcpu_calc_fc_sizes(size_t static_size,
!defined(CONFIG_HAVE_SETUP_PER_CPU_AREA)
/**
* pcpu_embed_first_chunk - embed the first percpu chunk into bootmem
- * @static_size: the size of static percpu area in bytes
* @reserved_size: the size of reserved percpu area in bytes
* @dyn_size: free size for dynamic allocation in bytes, -1 for auto
*
@@ -1489,9 +1488,9 @@ static inline size_t pcpu_calc_fc_sizes(size_t static_size,
* The determined pcpu_unit_size which can be used to initialize
* percpu access on success, -errno on failure.
*/
-ssize_t __init pcpu_embed_first_chunk(size_t static_size, size_t reserved_size,
- ssize_t dyn_size)
+ssize_t __init pcpu_embed_first_chunk(size_t reserved_size, ssize_t dyn_size)
{
+ const size_t static_size = __per_cpu_end - __per_cpu_start;
size_t size_sum, unit_size, chunk_size;
void *base;
unsigned int cpu;
@@ -1536,7 +1535,6 @@ ssize_t __init pcpu_embed_first_chunk(size_t static_size, size_t reserved_size,
#ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK
/**
* 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
@@ -1552,12 +1550,13 @@ 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_page_first_chunk(size_t static_size, size_t reserved_size,
+ssize_t __init pcpu_page_first_chunk(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;
+ const size_t static_size = __per_cpu_end - __per_cpu_start;
char psize_str[16];
int unit_pages;
size_t pages_size;
@@ -1641,7 +1640,6 @@ out_free_ar:
#ifdef CONFIG_NEED_PER_CPU_LPAGE_FIRST_CHUNK
/**
* pcpu_lpage_build_unit_map - build unit_map for large page remapping
- * @static_size: the size of static percpu area in bytes
* @reserved_size: the size of reserved percpu area in bytes
* @dyn_sizep: in/out parameter for dynamic size, -1 for auto
* @unit_sizep: out parameter for unit size
@@ -1661,13 +1659,14 @@ out_free_ar:
* On success, fills in @unit_map, sets *@dyn_sizep, *@unit_sizep and
* returns the number of units to be allocated. -errno on failure.
*/
-int __init pcpu_lpage_build_unit_map(size_t static_size, size_t reserved_size,
- ssize_t *dyn_sizep, size_t *unit_sizep,
- size_t lpage_size, int *unit_map,
+int __init pcpu_lpage_build_unit_map(size_t reserved_size, ssize_t *dyn_sizep,
+ size_t *unit_sizep, size_t lpage_size,
+ int *unit_map,
pcpu_fc_cpu_distance_fn_t cpu_distance_fn)
{
static int group_map[NR_CPUS] __initdata;
static int group_cnt[NR_CPUS] __initdata;
+ const size_t static_size = __per_cpu_end - __per_cpu_start;
int group_cnt_max = 0;
size_t size_sum, min_unit_size, alloc_size;
int upa, max_upa, uninitialized_var(best_upa); /* units_per_alloc */
@@ -1819,7 +1818,6 @@ static void __init pcpul_lpage_dump_cfg(const char *lvl, size_t static_size,

/**
* pcpu_lpage_first_chunk - remap the first percpu chunk using large page
- * @static_size: the size of static percpu area in bytes
* @reserved_size: the size of reserved percpu area in bytes
* @dyn_size: free size for dynamic allocation in bytes
* @unit_size: unit size in bytes
@@ -1850,15 +1848,15 @@ static void __init pcpul_lpage_dump_cfg(const char *lvl, size_t static_size,
* The determined pcpu_unit_size which can be used to initialize
* percpu access on success, -errno on failure.
*/
-ssize_t __init pcpu_lpage_first_chunk(size_t static_size, size_t reserved_size,
- size_t dyn_size, size_t unit_size,
- size_t lpage_size, const int *unit_map,
- int nr_units,
+ssize_t __init pcpu_lpage_first_chunk(size_t reserved_size, size_t dyn_size,
+ size_t unit_size, size_t lpage_size,
+ const int *unit_map, int nr_units,
pcpu_fc_alloc_fn_t alloc_fn,
pcpu_fc_free_fn_t free_fn,
pcpu_fc_map_fn_t map_fn)
{
static struct vm_struct vm;
+ const size_t static_size = __per_cpu_end - __per_cpu_start;
size_t chunk_size = unit_size * nr_units;
size_t map_size;
unsigned int cpu;
@@ -2037,7 +2035,6 @@ EXPORT_SYMBOL(__per_cpu_offset);

void __init setup_per_cpu_areas(void)
{
- size_t static_size = __per_cpu_end - __per_cpu_start;
ssize_t unit_size;
unsigned long delta;
unsigned int cpu;
@@ -2046,7 +2043,7 @@ void __init setup_per_cpu_areas(void)
* Always reserve area for module percpu variables. That's
* what the legacy allocator did.
*/
- unit_size = pcpu_embed_first_chunk(static_size, PERCPU_MODULE_RESERVE,
+ unit_size = pcpu_embed_first_chunk(PERCPU_MODULE_RESERVE,
PERCPU_DYNAMIC_RESERVE);
if (unit_size < 0)
panic("Failed to initialized percpu areas.");
--
1.6.0.2