From ac3e3c5b1164397656df81b9e9ab4991184d3236 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sun, 28 Apr 2013 21:42:33 -0400 Subject: [PATCH] don't bother with deferred freeing of fdtables Signed-off-by: Al Viro --- fs/file.c | 68 ++--------------------------------------- include/linux/fdtable.h | 1 - 2 files changed, 2 insertions(+), 67 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 #include -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 fb7dacae0522..085197bd8812 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) -- 2.20.1