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authorAl Viro <viro@zeniv.linux.org.uk>2013-04-28 21:42:33 -0400
committerAl Viro <viro@zeniv.linux.org.uk>2013-05-01 17:31:42 -0400
commitac3e3c5b1164397656df81b9e9ab4991184d3236 (patch)
tree3f2f0db03d858eff7a97cc71779cd844a8387391
parent094dd33b178d52c9ef959ed62cc0759310bd9657 (diff)
don't bother with deferred freeing of fdtables
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
-rw-r--r--fs/file.c68
-rw-r--r--include/linux/fdtable.h1
2 files changed, 2 insertions, 67 deletions
diff --git a/fs/file.c b/fs/file.c
index 3906d9577a1..4a78f981557 100644
--- a/fs/file.c
+++ b/fs/file.c
@@ -23,24 +23,10 @@
#include <linux/rcupdate.h>
#include <linux/workqueue.h>
-struct fdtable_defer {
- spinlock_t lock;
- struct work_struct wq;
- struct fdtable *next;
-};
-
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 void *alloc_fdmem(size_t size)
{
/*
@@ -67,46 +53,9 @@ static void __free_fdtable(struct fdtable *fdt)
kfree(fdt);
}
-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;
-
- __free_fdtable(fdt);
- fdt = next;
- }
-}
-
static void free_fdtable_rcu(struct rcu_head *rcu)
{
- struct fdtable *fdt = container_of(rcu, struct fdtable, rcu);
- struct fdtable_defer *fddef;
-
- BUG_ON(!fdt);
- BUG_ON(fdt->max_fds <= NR_OPEN_DEFAULT);
-
- if (!is_vmalloc_addr(fdt->fd) && !is_vmalloc_addr(fdt->open_fds)) {
- 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);
- }
+ __free_fdtable(container_of(rcu, struct fdtable, rcu));
}
/*
@@ -174,7 +123,6 @@ static struct fdtable * alloc_fdtable(unsigned int nr)
fdt->open_fds = data;
data += nr / BITS_PER_BYTE;
fdt->close_on_exec = data;
- fdt->next = NULL;
return fdt;
@@ -221,7 +169,7 @@ static int expand_fdtable(struct files_struct *files, int nr)
/* Continue as planned */
copy_fdtable(new_fdt, cur_fdt);
rcu_assign_pointer(files->fdt, new_fdt);
- if (cur_fdt->max_fds > NR_OPEN_DEFAULT)
+ if (cur_fdt != &files->fdtab)
call_rcu(&cur_fdt->rcu, free_fdtable_rcu);
} else {
/* Somebody else expanded, so undo our attempt */
@@ -316,7 +264,6 @@ struct files_struct *dup_fd(struct files_struct *oldf, int *errorp)
new_fdt->close_on_exec = newf->close_on_exec_init;
new_fdt->open_fds = newf->open_fds_init;
new_fdt->fd = &newf->fd_array[0];
- new_fdt->next = NULL;
spin_lock(&oldf->file_lock);
old_fdt = files_fdtable(oldf);
@@ -490,19 +437,8 @@ void exit_files(struct task_struct *tsk)
}
}
-static void 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;
}
diff --git a/include/linux/fdtable.h b/include/linux/fdtable.h
index fb7dacae052..085197bd881 100644
--- a/include/linux/fdtable.h
+++ b/include/linux/fdtable.h
@@ -27,7 +27,6 @@ struct fdtable {
unsigned long *close_on_exec;
unsigned long *open_fds;
struct rcu_head rcu;
- struct fdtable *next;
};
static inline bool close_on_exec(int fd, const struct fdtable *fdt)