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Message-Id: <1273744873-10243-1-git-send-email-xiaosuo@gmail.com>
Date: Thu, 13 May 2010 18:01:13 +0800
From: Changli Gao <xiaosuo@...il.com>
To: akpm@...ux-foundation.org
Cc: Alexander Viro <viro@...iv.linux.org.uk>,
linux-fsdevel@...r.kernel.org, linux-kernel@...r.kernel.org,
Changli Gao <xiaosuo@...il.com>
Subject: [PATCH 4/9] file: use kvmalloc, kvfree and kvfree_inatomic
use kvmalloc, kvfree and kvfree_inatomic
use kvmalloc, kvfree and kvfree_inatomic
Signed-off-by: Changli Gao <xiaosuo@...il.com>
----
fs/file.c | 109 +++++++++-----------------------------------------------------
1 file changed, 16 insertions(+), 93 deletions(-)
diff --git a/fs/file.c b/fs/file.c
index 34bb7f7..54e70b6 100644
--- a/fs/file.c
+++ b/fs/file.c
@@ -12,7 +12,6 @@
#include <linux/time.h>
#include <linux/sched.h>
#include <linux/slab.h>
-#include <linux/vmalloc.h>
#include <linux/file.h>
#include <linux/fdtable.h>
#include <linux/bitops.h>
@@ -31,61 +30,16 @@ int sysctl_nr_open __read_mostly = 1024*1024;
int sysctl_nr_open_min = BITS_PER_LONG;
int sysctl_nr_open_max = 1024 * 1024; /* raised later */
-/*
- * We use this list to defer free fdtables that have vmalloced
- * sets/arrays. By keeping a per-cpu list, we avoid having to embed
- * the work_struct in fdtable itself which avoids a 64 byte (i386) increase in
- * this per-task structure.
- */
-static DEFINE_PER_CPU(struct fdtable_defer, fdtable_defer_list);
-
-static inline void * alloc_fdmem(unsigned int size)
-{
- if (size <= PAGE_SIZE)
- return kmalloc(size, GFP_KERNEL);
- else
- return vmalloc(size);
-}
-
-static inline void free_fdarr(struct fdtable *fdt)
+static void __free_fdtable(struct fdtable *fdt)
{
- if (fdt->max_fds <= (PAGE_SIZE / sizeof(struct file *)))
- kfree(fdt->fd);
- else
- vfree(fdt->fd);
-}
-
-static inline void free_fdset(struct fdtable *fdt)
-{
- if (fdt->max_fds <= (PAGE_SIZE * BITS_PER_BYTE / 2))
- kfree(fdt->open_fds);
- else
- vfree(fdt->open_fds);
-}
-
-static void free_fdtable_work(struct work_struct *work)
-{
- struct fdtable_defer *f =
- container_of(work, struct fdtable_defer, wq);
- struct fdtable *fdt;
-
- spin_lock_bh(&f->lock);
- fdt = f->next;
- f->next = NULL;
- spin_unlock_bh(&f->lock);
- while(fdt) {
- struct fdtable *next = fdt->next;
- vfree(fdt->fd);
- free_fdset(fdt);
- kfree(fdt);
- fdt = next;
- }
+ kvfree(fdt->fd);
+ kvfree(fdt->open_fds);
+ kfree(fdt);
}
void free_fdtable_rcu(struct rcu_head *rcu)
{
struct fdtable *fdt = container_of(rcu, struct fdtable, rcu);
- struct fdtable_defer *fddef;
BUG_ON(!fdt);
@@ -98,20 +52,9 @@ void free_fdtable_rcu(struct rcu_head *rcu)
container_of(fdt, struct files_struct, fdtab));
return;
}
- if (fdt->max_fds <= (PAGE_SIZE / sizeof(struct file *))) {
- kfree(fdt->fd);
- kfree(fdt->open_fds);
- kfree(fdt);
- } else {
- fddef = &get_cpu_var(fdtable_defer_list);
- spin_lock(&fddef->lock);
- fdt->next = fddef->next;
- fddef->next = fdt;
- /* vmallocs are handled from the workqueue context */
- schedule_work(&fddef->wq);
- spin_unlock(&fddef->lock);
- put_cpu_var(fdtable_defer_list);
- }
+ kvfree_inatomic(fdt->fd);
+ kvfree_inatomic(fdt->open_fds);
+ kfree(fdt);
}
/*
@@ -167,12 +110,12 @@ static struct fdtable * alloc_fdtable(unsigned int nr)
if (!fdt)
goto out;
fdt->max_fds = nr;
- data = alloc_fdmem(nr * sizeof(struct file *));
+ data = kvmalloc(nr * sizeof(struct file *));
if (!data)
goto out_fdt;
fdt->fd = (struct file **)data;
- data = alloc_fdmem(max_t(unsigned int,
- 2 * nr / BITS_PER_BYTE, L1_CACHE_BYTES));
+ data = kvmalloc(max_t(unsigned int,
+ 2 * nr / BITS_PER_BYTE, L1_CACHE_BYTES));
if (!data)
goto out_arr;
fdt->open_fds = (fd_set *)data;
@@ -184,7 +127,7 @@ static struct fdtable * alloc_fdtable(unsigned int nr)
return fdt;
out_arr:
- free_fdarr(fdt);
+ kvfree(fdt->fd);
out_fdt:
kfree(fdt);
out:
@@ -214,9 +157,7 @@ static int expand_fdtable(struct files_struct *files, int nr)
* caller and alloc_fdtable(). Cheaper to catch it here...
*/
if (unlikely(new_fdt->max_fds <= nr)) {
- free_fdarr(new_fdt);
- free_fdset(new_fdt);
- kfree(new_fdt);
+ __free_fdtable(new_fdt);
return -EMFILE;
}
/*
@@ -232,9 +173,7 @@ static int expand_fdtable(struct files_struct *files, int nr)
free_fdtable(cur_fdt);
} else {
/* Somebody else expanded, so undo our attempt */
- free_fdarr(new_fdt);
- free_fdset(new_fdt);
- kfree(new_fdt);
+ __free_fdtable(new_fdt);
}
return 1;
}
@@ -325,11 +264,8 @@ struct files_struct *dup_fd(struct files_struct *oldf, int *errorp)
while (unlikely(open_files > new_fdt->max_fds)) {
spin_unlock(&oldf->file_lock);
- if (new_fdt != &newf->fdtab) {
- free_fdarr(new_fdt);
- free_fdset(new_fdt);
- kfree(new_fdt);
- }
+ if (new_fdt != &newf->fdtab)
+ __free_fdtable(new_fdt);
new_fdt = alloc_fdtable(open_files - 1);
if (!new_fdt) {
@@ -339,9 +275,7 @@ struct files_struct *dup_fd(struct files_struct *oldf, int *errorp)
/* beyond sysctl_nr_open; nothing to do */
if (unlikely(new_fdt->max_fds < open_files)) {
- free_fdarr(new_fdt);
- free_fdset(new_fdt);
- kfree(new_fdt);
+ __free_fdtable(new_fdt);
*errorp = -EMFILE;
goto out_release;
}
@@ -405,19 +339,8 @@ out:
return NULL;
}
-static void __devinit fdtable_defer_list_init(int cpu)
-{
- struct fdtable_defer *fddef = &per_cpu(fdtable_defer_list, cpu);
- spin_lock_init(&fddef->lock);
- INIT_WORK(&fddef->wq, free_fdtable_work);
- fddef->next = NULL;
-}
-
void __init files_defer_init(void)
{
- int i;
- for_each_possible_cpu(i)
- fdtable_defer_list_init(i);
sysctl_nr_open_max = min((size_t)INT_MAX, ~(size_t)0/sizeof(void *)) &
-BITS_PER_LONG;
}
--
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