don't bother with deferred freeing of fdtables

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 2 insertions, 66 deletions

diff --git a/fs/file.c b/fs/file.c
index 3906d9577a18..4a78f981557a 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;
 }