Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755322AbbK0S5K (ORCPT ); Fri, 27 Nov 2015 13:57:10 -0500 Received: from mx1.redhat.com ([209.132.183.28]:55297 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755017AbbK0S4q (ORCPT ); Fri, 27 Nov 2015 13:56:46 -0500 Date: Fri, 27 Nov 2015 19:57:25 +0100 From: Oleg Nesterov To: Aleksa Sarai , Johannes Weiner , Li Zefan , Tejun Heo Cc: linux-kernel@vger.kernel.org Subject: [PATCH 3/3] cgroup: kill cgrp_ss_priv[CGROUP_CANFORK_COUNT] and friends Message-ID: <20151127185725.GA14692@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20151127185705.GA14669@redhat.com> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 10901 Lines: 326 Now that nobody use the "priv" arg passed to can_fork/cancel_fork/fork we can kill CGROUP_CANFORK_COUNT/SUBSYS_TAG/etc and cgrp_ss_priv[] in copy_process(). Signed-off-by: Oleg Nesterov --- include/linux/cgroup-defs.h | 12 +++--------- include/linux/cgroup.h | 19 ++++++------------- include/linux/cgroup_subsys.h | 18 ------------------ kernel/cgroup.c | 30 +++++++----------------------- kernel/cgroup_freezer.c | 2 +- kernel/cgroup_pids.c | 4 ++-- kernel/fork.c | 7 +++---- kernel/sched/core.c | 2 +- 8 files changed, 23 insertions(+), 71 deletions(-) diff --git a/include/linux/cgroup-defs.h b/include/linux/cgroup-defs.h index 60d44b2..ed98f99 100644 --- a/include/linux/cgroup-defs.h +++ b/include/linux/cgroup-defs.h @@ -34,17 +34,12 @@ struct seq_file; /* define the enumeration of all cgroup subsystems */ #define SUBSYS(_x) _x ## _cgrp_id, -#define SUBSYS_TAG(_t) CGROUP_ ## _t, \ - __unused_tag_ ## _t = CGROUP_ ## _t - 1, enum cgroup_subsys_id { #include CGROUP_SUBSYS_COUNT, }; -#undef SUBSYS_TAG #undef SUBSYS -#define CGROUP_CANFORK_COUNT (CGROUP_CANFORK_END - CGROUP_CANFORK_START) - /* bits in struct cgroup_subsys_state flags field */ enum { CSS_NO_REF = (1 << 0), /* no reference counting for this css */ @@ -432,9 +427,9 @@ struct cgroup_subsys { struct cgroup_taskset *tset); void (*attach)(struct cgroup_subsys_state *css, struct cgroup_taskset *tset); - int (*can_fork)(struct task_struct *task, void **priv_p); - void (*cancel_fork)(struct task_struct *task, void *priv); - void (*fork)(struct task_struct *task, void *priv); + int (*can_fork)(struct task_struct *task); + void (*cancel_fork)(struct task_struct *task); + void (*fork)(struct task_struct *task); void (*exit)(struct task_struct *task); void (*free)(struct task_struct *task); void (*bind)(struct cgroup_subsys_state *root_css); @@ -520,7 +515,6 @@ static inline void cgroup_threadgroup_change_end(struct task_struct *tsk) #else /* CONFIG_CGROUPS */ -#define CGROUP_CANFORK_COUNT 0 #define CGROUP_SUBSYS_COUNT 0 static inline void cgroup_threadgroup_change_begin(struct task_struct *tsk) {} diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index 22e3754..f15e86d 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -95,12 +95,9 @@ int proc_cgroup_show(struct seq_file *m, struct pid_namespace *ns, struct pid *pid, struct task_struct *tsk); void cgroup_fork(struct task_struct *p); -extern int cgroup_can_fork(struct task_struct *p, - void *ss_priv[CGROUP_CANFORK_COUNT]); -extern void cgroup_cancel_fork(struct task_struct *p, - void *ss_priv[CGROUP_CANFORK_COUNT]); -extern void cgroup_post_fork(struct task_struct *p, - void *old_ss_priv[CGROUP_CANFORK_COUNT]); +extern int cgroup_can_fork(struct task_struct *p); +extern void cgroup_cancel_fork(struct task_struct *p); +extern void cgroup_post_fork(struct task_struct *p); void cgroup_exit(struct task_struct *p); void cgroup_free(struct task_struct *p); @@ -540,13 +537,9 @@ static inline int cgroupstats_build(struct cgroupstats *stats, struct dentry *dentry) { return -EINVAL; } static inline void cgroup_fork(struct task_struct *p) {} -static inline int cgroup_can_fork(struct task_struct *p, - void *ss_priv[CGROUP_CANFORK_COUNT]) -{ return 0; } -static inline void cgroup_cancel_fork(struct task_struct *p, - void *ss_priv[CGROUP_CANFORK_COUNT]) {} -static inline void cgroup_post_fork(struct task_struct *p, - void *ss_priv[CGROUP_CANFORK_COUNT]) {} +static inline int cgroup_can_fork(struct task_struct *p) { return 0; } +static inline void cgroup_cancel_fork(struct task_struct *p) {} +static inline void cgroup_post_fork(struct task_struct *p) {} static inline void cgroup_exit(struct task_struct *p) {} static inline void cgroup_free(struct task_struct *p) {} diff --git a/include/linux/cgroup_subsys.h b/include/linux/cgroup_subsys.h index 1a96fda..0df0336 100644 --- a/include/linux/cgroup_subsys.h +++ b/include/linux/cgroup_subsys.h @@ -6,14 +6,8 @@ /* * This file *must* be included with SUBSYS() defined. - * SUBSYS_TAG() is a noop if undefined. */ -#ifndef SUBSYS_TAG -#define __TMP_SUBSYS_TAG -#define SUBSYS_TAG(_x) -#endif - #if IS_ENABLED(CONFIG_CPUSETS) SUBSYS(cpuset) #endif @@ -58,17 +52,10 @@ SUBSYS(net_prio) SUBSYS(hugetlb) #endif -/* - * Subsystems that implement the can_fork() family of callbacks. - */ -SUBSYS_TAG(CANFORK_START) - #if IS_ENABLED(CONFIG_CGROUP_PIDS) SUBSYS(pids) #endif -SUBSYS_TAG(CANFORK_END) - /* * The following subsystems are not supported on the default hierarchy. */ @@ -76,11 +63,6 @@ SUBSYS_TAG(CANFORK_END) SUBSYS(debug) #endif -#ifdef __TMP_SUBSYS_TAG -#undef __TMP_SUBSYS_TAG -#undef SUBSYS_TAG -#endif - /* * DO NOT ADD ANY SUBSYSTEM WITHOUT EXPLICIT ACKS FROM CGROUP MAINTAINERS. */ diff --git a/kernel/cgroup.c b/kernel/cgroup.c index f1603c1..7380a37 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -5432,19 +5432,6 @@ static const struct file_operations proc_cgroupstats_operations = { .release = single_release, }; -static void **subsys_canfork_priv_p(void *ss_priv[CGROUP_CANFORK_COUNT], int i) -{ - if (CGROUP_CANFORK_START <= i && i < CGROUP_CANFORK_END) - return &ss_priv[i - CGROUP_CANFORK_START]; - return NULL; -} - -static void *subsys_canfork_priv(void *ss_priv[CGROUP_CANFORK_COUNT], int i) -{ - void **private = subsys_canfork_priv_p(ss_priv, i); - return private ? *private : NULL; -} - /** * cgroup_fork - initialize cgroup related fields during copy_process() * @child: pointer to task_struct of forking parent process. @@ -5467,14 +5454,13 @@ void cgroup_fork(struct task_struct *child) * returns an error, the fork aborts with that error code. This allows for * a cgroup subsystem to conditionally allow or deny new forks. */ -int cgroup_can_fork(struct task_struct *child, - void *ss_priv[CGROUP_CANFORK_COUNT]) +int cgroup_can_fork(struct task_struct *child) { struct cgroup_subsys *ss; int i, j, ret; for_each_subsys_which(ss, i, &have_canfork_callback) { - ret = ss->can_fork(child, subsys_canfork_priv_p(ss_priv, i)); + ret = ss->can_fork(child); if (ret) goto out_revert; } @@ -5486,7 +5472,7 @@ out_revert: if (j >= i) break; if (ss->cancel_fork) - ss->cancel_fork(child, subsys_canfork_priv(ss_priv, j)); + ss->cancel_fork(child); } return ret; @@ -5499,15 +5485,14 @@ out_revert: * This calls the cancel_fork() callbacks if a fork failed *after* * cgroup_can_fork() succeded. */ -void cgroup_cancel_fork(struct task_struct *child, - void *ss_priv[CGROUP_CANFORK_COUNT]) +void cgroup_cancel_fork(struct task_struct *child) { struct cgroup_subsys *ss; int i; for_each_subsys(ss, i) if (ss->cancel_fork) - ss->cancel_fork(child, subsys_canfork_priv(ss_priv, i)); + ss->cancel_fork(child); } /** @@ -5520,8 +5505,7 @@ void cgroup_cancel_fork(struct task_struct *child, * cgroup_task_iter_start() - to guarantee that the new task ends up on its * list. */ -void cgroup_post_fork(struct task_struct *child, - void *old_ss_priv[CGROUP_CANFORK_COUNT]) +void cgroup_post_fork(struct task_struct *child) { struct cgroup_subsys *ss; int i; @@ -5565,7 +5549,7 @@ void cgroup_post_fork(struct task_struct *child, * and addition to css_set. */ for_each_subsys_which(ss, i, &have_fork_callback) - ss->fork(child, subsys_canfork_priv(old_ss_priv, i)); + ss->fork(child); } /** diff --git a/kernel/cgroup_freezer.c b/kernel/cgroup_freezer.c index f1b30ad..92b98cc 100644 --- a/kernel/cgroup_freezer.c +++ b/kernel/cgroup_freezer.c @@ -203,7 +203,7 @@ static void freezer_attach(struct cgroup_subsys_state *new_css, * to do anything as freezer_attach() will put @task into the appropriate * state. */ -static void freezer_fork(struct task_struct *task, void *private) +static void freezer_fork(struct task_struct *task) { struct freezer *freezer; diff --git a/kernel/cgroup_pids.c b/kernel/cgroup_pids.c index de3359a..7f19e6c 100644 --- a/kernel/cgroup_pids.c +++ b/kernel/cgroup_pids.c @@ -209,7 +209,7 @@ static void pids_cancel_attach(struct cgroup_subsys_state *css, * task_css_check(true) in pids_can_fork() and pids_cancel_fork() relies * on threadgroup_change_begin() held by the copy_process(). */ -static int pids_can_fork(struct task_struct *task, void **priv_p) +static int pids_can_fork(struct task_struct *task) { struct cgroup_subsys_state *css; struct pids_cgroup *pids; @@ -219,7 +219,7 @@ static int pids_can_fork(struct task_struct *task, void **priv_p) return pids_try_charge(pids, 1); } -static void pids_cancel_fork(struct task_struct *task, void *priv) +static void pids_cancel_fork(struct task_struct *task) { struct cgroup_subsys_state *css; struct pids_cgroup *pids; diff --git a/kernel/fork.c b/kernel/fork.c index fce002e..ba7d1c0 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1249,7 +1249,6 @@ static struct task_struct *copy_process(unsigned long clone_flags, { int retval; struct task_struct *p; - void *cgrp_ss_priv[CGROUP_CANFORK_COUNT] = {}; if ((clone_flags & (CLONE_NEWNS|CLONE_FS)) == (CLONE_NEWNS|CLONE_FS)) return ERR_PTR(-EINVAL); @@ -1526,7 +1525,7 @@ static struct task_struct *copy_process(unsigned long clone_flags, * between here and cgroup_post_fork() if an organisation operation is in * progress. */ - retval = cgroup_can_fork(p, cgrp_ss_priv); + retval = cgroup_can_fork(p); if (retval) goto bad_fork_free_pid; @@ -1608,7 +1607,7 @@ static struct task_struct *copy_process(unsigned long clone_flags, write_unlock_irq(&tasklist_lock); proc_fork_connector(p); - cgroup_post_fork(p, cgrp_ss_priv); + cgroup_post_fork(p); threadgroup_change_end(current); perf_event_fork(p); @@ -1618,7 +1617,7 @@ static struct task_struct *copy_process(unsigned long clone_flags, return p; bad_fork_cancel_cgroup: - cgroup_cancel_fork(p, cgrp_ss_priv); + cgroup_cancel_fork(p); bad_fork_free_pid: if (pid != &init_struct_pid) free_pid(pid); diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 4d568ac..d6bd5eb 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -8212,7 +8212,7 @@ static void cpu_cgroup_css_offline(struct cgroup_subsys_state *css) sched_offline_group(tg); } -static void cpu_cgroup_fork(struct task_struct *task, void *private) +static void cpu_cgroup_fork(struct task_struct *task) { sched_move_task(task); } -- 1.5.5.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/