From 17cf22c33e1f1b5e435469c84e43872579497653 Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Tue, 2 Mar 2010 14:51:53 -0800 Subject: [PATCH] pidns: Use task_active_pid_ns where appropriate The expressions tsk->nsproxy->pid_ns and task_active_pid_ns aka ns_of_pid(task_pid(tsk)) should have the same number of cache line misses with the practical difference that ns_of_pid(task_pid(tsk)) is released later in a processes life. Furthermore by using task_active_pid_ns it becomes trivial to write an unshare implementation for the the pid namespace. So I have used task_active_pid_ns everywhere I can. In fork since the pid has not yet been attached to the process I use ns_of_pid, to achieve the same effect. Signed-off-by: Eric W. Biederman --- arch/powerpc/platforms/cell/spufs/sched.c | 2 +- arch/um/drivers/mconsole_kern.c | 2 +- drivers/staging/android/binder.c | 3 ++- fs/hppfs/hppfs.c | 2 +- fs/proc/root.c | 2 +- kernel/cgroup.c | 2 +- kernel/events/core.c | 2 +- kernel/fork.c | 2 +- kernel/nsproxy.c | 2 +- kernel/pid.c | 8 ++++---- kernel/signal.c | 2 +- kernel/sysctl_binary.c | 2 +- 12 files changed, 16 insertions(+), 15 deletions(-) diff --git a/arch/powerpc/platforms/cell/spufs/sched.c b/arch/powerpc/platforms/cell/spufs/sched.c index 965d381abd75..25db92a8e1cf 100644 --- a/arch/powerpc/platforms/cell/spufs/sched.c +++ b/arch/powerpc/platforms/cell/spufs/sched.c @@ -1094,7 +1094,7 @@ static int show_spu_loadavg(struct seq_file *s, void *private) LOAD_INT(c), LOAD_FRAC(c), count_active_contexts(), atomic_read(&nr_spu_contexts), - current->nsproxy->pid_ns->last_pid); + task_active_pid_ns(current)->last_pid); return 0; } diff --git a/arch/um/drivers/mconsole_kern.c b/arch/um/drivers/mconsole_kern.c index 79ccfe6c7078..7fc71c628267 100644 --- a/arch/um/drivers/mconsole_kern.c +++ b/arch/um/drivers/mconsole_kern.c @@ -123,7 +123,7 @@ void mconsole_log(struct mc_request *req) void mconsole_proc(struct mc_request *req) { - struct vfsmount *mnt = current->nsproxy->pid_ns->proc_mnt; + struct vfsmount *mnt = task_active_pid_ns(current)->proc_mnt; char *buf; int len; struct file *file; diff --git a/drivers/staging/android/binder.c b/drivers/staging/android/binder.c index 5d4610babd8a..a97bbcd1c9ea 100644 --- a/drivers/staging/android/binder.c +++ b/drivers/staging/android/binder.c @@ -33,6 +33,7 @@ #include #include #include +#include #include "binder.h" @@ -2344,7 +2345,7 @@ retry: if (t->from) { struct task_struct *sender = t->from->proc->tsk; tr.sender_pid = task_tgid_nr_ns(sender, - current->nsproxy->pid_ns); + task_active_pid_ns(current)); } else { tr.sender_pid = 0; } diff --git a/fs/hppfs/hppfs.c b/fs/hppfs/hppfs.c index 78f21f8dc2ec..43b315f2002b 100644 --- a/fs/hppfs/hppfs.c +++ b/fs/hppfs/hppfs.c @@ -710,7 +710,7 @@ static int hppfs_fill_super(struct super_block *sb, void *d, int silent) struct vfsmount *proc_mnt; int err = -ENOENT; - proc_mnt = mntget(current->nsproxy->pid_ns->proc_mnt); + proc_mnt = mntget(task_active_pid_ns(current)->proc_mnt); if (IS_ERR(proc_mnt)) goto out; diff --git a/fs/proc/root.c b/fs/proc/root.c index 13ef6247e7a3..fc1609321a78 100644 --- a/fs/proc/root.c +++ b/fs/proc/root.c @@ -106,7 +106,7 @@ static struct dentry *proc_mount(struct file_system_type *fs_type, ns = (struct pid_namespace *)data; options = NULL; } else { - ns = current->nsproxy->pid_ns; + ns = task_active_pid_ns(current); options = data; } diff --git a/kernel/cgroup.c b/kernel/cgroup.c index f24f724620dd..0dbfba2efa77 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -3390,7 +3390,7 @@ static struct cgroup_pidlist *cgroup_pidlist_find(struct cgroup *cgrp, { struct cgroup_pidlist *l; /* don't need task_nsproxy() if we're looking at ourself */ - struct pid_namespace *ns = current->nsproxy->pid_ns; + struct pid_namespace *ns = task_active_pid_ns(current); /* * We can't drop the pidlist_mutex before taking the l->mutex in case diff --git a/kernel/events/core.c b/kernel/events/core.c index dbccf83c134d..738f3564e83b 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -6155,7 +6155,7 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu, event->parent = parent_event; - event->ns = get_pid_ns(current->nsproxy->pid_ns); + event->ns = get_pid_ns(task_active_pid_ns(current)); event->id = atomic64_inc_return(&perf_event_id); event->state = PERF_EVENT_STATE_INACTIVE; diff --git a/kernel/fork.c b/kernel/fork.c index 8b20ab7d3aa2..7798c247f4b9 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1442,7 +1442,7 @@ static struct task_struct *copy_process(unsigned long clone_flags, if (thread_group_leader(p)) { if (is_child_reaper(pid)) - p->nsproxy->pid_ns->child_reaper = p; + ns_of_pid(pid)->child_reaper = p; p->signal->leader_pid = pid; p->signal->tty = tty_kref_get(current->signal->tty); diff --git a/kernel/nsproxy.c b/kernel/nsproxy.c index ca27d2c5264d..acc92680381a 100644 --- a/kernel/nsproxy.c +++ b/kernel/nsproxy.c @@ -84,7 +84,7 @@ static struct nsproxy *create_new_namespaces(unsigned long flags, goto out_ipc; } - new_nsp->pid_ns = copy_pid_ns(flags, task_cred_xxx(tsk, user_ns), task_active_pid_ns(tsk)); + new_nsp->pid_ns = copy_pid_ns(flags, task_cred_xxx(tsk, user_ns), tsk->nsproxy->pid_ns); if (IS_ERR(new_nsp->pid_ns)) { err = PTR_ERR(new_nsp->pid_ns); goto out_pid; diff --git a/kernel/pid.c b/kernel/pid.c index 2a624f1486e1..3a5f238c1ca0 100644 --- a/kernel/pid.c +++ b/kernel/pid.c @@ -345,7 +345,7 @@ EXPORT_SYMBOL_GPL(find_pid_ns); struct pid *find_vpid(int nr) { - return find_pid_ns(nr, current->nsproxy->pid_ns); + return find_pid_ns(nr, task_active_pid_ns(current)); } EXPORT_SYMBOL_GPL(find_vpid); @@ -429,7 +429,7 @@ struct task_struct *find_task_by_pid_ns(pid_t nr, struct pid_namespace *ns) struct task_struct *find_task_by_vpid(pid_t vnr) { - return find_task_by_pid_ns(vnr, current->nsproxy->pid_ns); + return find_task_by_pid_ns(vnr, task_active_pid_ns(current)); } struct pid *get_task_pid(struct task_struct *task, enum pid_type type) @@ -484,7 +484,7 @@ EXPORT_SYMBOL_GPL(pid_nr_ns); pid_t pid_vnr(struct pid *pid) { - return pid_nr_ns(pid, current->nsproxy->pid_ns); + return pid_nr_ns(pid, task_active_pid_ns(current)); } EXPORT_SYMBOL_GPL(pid_vnr); @@ -495,7 +495,7 @@ pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type, rcu_read_lock(); if (!ns) - ns = current->nsproxy->pid_ns; + ns = task_active_pid_ns(current); if (likely(pid_alive(task))) { if (type != PIDTYPE_PID) task = task->group_leader; diff --git a/kernel/signal.c b/kernel/signal.c index 0af8868525d6..b2445d86f226 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -1752,7 +1752,7 @@ static void do_notify_parent_cldstop(struct task_struct *tsk, * see comment in do_notify_parent() about the following 4 lines */ rcu_read_lock(); - info.si_pid = task_pid_nr_ns(tsk, parent->nsproxy->pid_ns); + info.si_pid = task_pid_nr_ns(tsk, task_active_pid_ns(parent)); info.si_uid = from_kuid_munged(task_cred_xxx(parent, user_ns), task_uid(tsk)); rcu_read_unlock(); diff --git a/kernel/sysctl_binary.c b/kernel/sysctl_binary.c index 65bdcf198d4e..5a6384450501 100644 --- a/kernel/sysctl_binary.c +++ b/kernel/sysctl_binary.c @@ -1344,7 +1344,7 @@ static ssize_t binary_sysctl(const int *name, int nlen, goto out_putname; } - mnt = current->nsproxy->pid_ns->proc_mnt; + mnt = task_active_pid_ns(current)->proc_mnt; file = file_open_root(mnt->mnt_root, mnt, pathname, flags); result = PTR_ERR(file); if (IS_ERR(file)) -- 2.20.1