- 03 8月, 2017 2 次提交
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由 Roman Gushchin 提交于
Creating cgroup hierearchies of unreasonable size can affect overall system performance. A user might want to limit the size of cgroup hierarchy. This is especially important if a user is delegating some cgroup sub-tree. To address this issue, introduce an ability to control the size of cgroup hierarchy. The cgroup.max.descendants control file allows to set the maximum allowed number of descendant cgroups. The cgroup.max.depth file controls the maximum depth of the cgroup tree. Both are single value r/w files, with "max" default value. The control files exist on each hierarchy level (including root). When a new cgroup is created, we check the total descendants and depth limits on each level, and if none of them are exceeded, a new cgroup is created. Only alive cgroups are counted, removed (dying) cgroups are ignored. Signed-off-by: NRoman Gushchin <guro@fb.com> Suggested-by: NTejun Heo <tj@kernel.org> Signed-off-by: NTejun Heo <tj@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: Waiman Long <longman@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: kernel-team@fb.com Cc: cgroups@vger.kernel.org Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org
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由 Roman Gushchin 提交于
Keep track of the number of online and dying descent cgroups. This data will be used later to add an ability to control cgroup hierarchy (limit the depth and the number of descent cgroups) and display hierarchy stats. Signed-off-by: NRoman Gushchin <guro@fb.com> Suggested-by: NTejun Heo <tj@kernel.org> Signed-off-by: NTejun Heo <tj@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: Waiman Long <longman@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: kernel-team@fb.com Cc: cgroups@vger.kernel.org Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org
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- 26 7月, 2017 2 次提交
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由 Tejun Heo 提交于
Explain cgroup_enable_threaded() and note that the function can never be called on the root cgroup. Signed-off-by: NTejun Heo <tj@kernel.org> Suggested-by: NWaiman Long <longman@redhat.com>
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由 Tejun Heo 提交于
cgroup_enable_threaded() checks that the cgroup doesn't have any tasks or children and fails the operation if so. This test is unnecessary because the first part is already checked by cgroup_can_be_thread_root() and the latter is unnecessary. The latter actually cause a behavioral oddity. Please consider the following hierarchy. All cgroups are domains. A / \ B C \ D If B is made threaded, C and D becomes invalid domains. Due to the no children restriction, threaded mode can't be enabled on C. For C and D, the only thing the user can do is removal. There is no reason for this restriction. Remove it. Acked-by: NWaiman Long <longman@redhat.com> Signed-off-by: NTejun Heo <tj@kernel.org>
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- 21 7月, 2017 6 次提交
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由 Waiman Long 提交于
Update debug controller so that it prints out debug info about thread mode. 1) The relationship between proc_cset and threaded_csets are displayed. 2) The status of being a thread root or threaded cgroup is displayed. This patch is extracted from Waiman's larger patch. v2: - Removed [thread root] / [threaded] from debug.cgroup_css_links file as the same information is available from cgroup.type. Suggested by Waiman. - Threaded marking is moved to the previous patch. Patch-originally-by: NWaiman Long <longman@redhat.com> Signed-off-by: NTejun Heo <tj@kernel.org>
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由 Tejun Heo 提交于
This patch implements cgroup v2 thread support. The goal of the thread mode is supporting hierarchical accounting and control at thread granularity while staying inside the resource domain model which allows coordination across different resource controllers and handling of anonymous resource consumptions. A cgroup is always created as a domain and can be made threaded by writing to the "cgroup.type" file. When a cgroup becomes threaded, it becomes a member of a threaded subtree which is anchored at the closest ancestor which isn't threaded. The threads of the processes which are in a threaded subtree can be placed anywhere without being restricted by process granularity or no-internal-process constraint. Note that the threads aren't allowed to escape to a different threaded subtree. To be used inside a threaded subtree, a controller should explicitly support threaded mode and be able to handle internal competition in the way which is appropriate for the resource. The root of a threaded subtree, the nearest ancestor which isn't threaded, is called the threaded domain and serves as the resource domain for the whole subtree. This is the last cgroup where domain controllers are operational and where all the domain-level resource consumptions in the subtree are accounted. This allows threaded controllers to operate at thread granularity when requested while staying inside the scope of system-level resource distribution. As the root cgroup is exempt from the no-internal-process constraint, it can serve as both a threaded domain and a parent to normal cgroups, so, unlike non-root cgroups, the root cgroup can have both domain and threaded children. Internally, in a threaded subtree, each css_set has its ->dom_cset pointing to a matching css_set which belongs to the threaded domain. This ensures that thread root level cgroup_subsys_state for all threaded controllers are readily accessible for domain-level operations. This patch enables threaded mode for the pids and perf_events controllers. Neither has to worry about domain-level resource consumptions and it's enough to simply set the flag. For more details on the interface and behavior of the thread mode, please refer to the section 2-2-2 in Documentation/cgroup-v2.txt added by this patch. v5: - Dropped silly no-op ->dom_cgrp init from cgroup_create(). Spotted by Waiman. - Documentation updated as suggested by Waiman. - cgroup.type content slightly reformatted. - Mark the debug controller threaded. v4: - Updated to the general idea of marking specific cgroups domain/threaded as suggested by PeterZ. v3: - Dropped "join" and always make mixed children join the parent's threaded subtree. v2: - After discussions with Waiman, support for mixed thread mode is added. This should address the issue that Peter pointed out where any nesting should be avoided for thread subtrees while coexisting with other domain cgroups. - Enabling / disabling thread mode now piggy backs on the existing control mask update mechanism. - Bug fixes and cleanup. Signed-off-by: NTejun Heo <tj@kernel.org> Cc: Waiman Long <longman@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org>
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由 Tejun Heo 提交于
cgroup v2 is in the process of growing thread granularity support. Once thread mode is enabled, the root cgroup of the subtree serves as the dom_cgrp to which the processes of the subtree conceptually belong and domain-level resource consumptions not tied to any specific task are charged. In the subtree, threads won't be subject to process granularity or no-internal-task constraint and can be distributed arbitrarily across the subtree. This patch implements a new task iterator flag CSS_TASK_ITER_THREADED, which, when used on a dom_cgrp, makes the iteration include the tasks on all the associated threaded css_sets. "cgroup.procs" read path is updated to use it so that reading the file on a proc_cgrp lists all processes. This will also be used by controller implementations which need to walk processes or tasks at the resource domain level. Task iteration is implemented nested in css_set iteration. If CSS_TASK_ITER_THREADED is specified, after walking tasks of each !threaded css_set, all the associated threaded css_sets are visited before moving onto the next !threaded css_set. v2: ->cur_pcset renamed to ->cur_dcset. Updated for the new enable-threaded-per-cgroup behavior. Signed-off-by: NTejun Heo <tj@kernel.org>
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由 Tejun Heo 提交于
cgroup v2 is in the process of growing thread granularity support. A threaded subtree is composed of a thread root and threaded cgroups which are proper members of the subtree. The root cgroup of the subtree serves as the domain cgroup to which the processes (as opposed to threads / tasks) of the subtree conceptually belong and domain-level resource consumptions not tied to any specific task are charged. Inside the subtree, threads won't be subject to process granularity or no-internal-task constraint and can be distributed arbitrarily across the subtree. This patch introduces cgroup->dom_cgrp along with threaded css_set handling. * cgroup->dom_cgrp points to self for normal and thread roots. For proper thread subtree members, points to the dom_cgrp (the thread root). * css_set->dom_cset points to self if for normal and thread roots. If threaded, points to the css_set which belongs to the cgrp->dom_cgrp. The dom_cgrp serves as the resource domain and keeps the matching csses available. The dom_cset holds those csses and makes them easily accessible. * All threaded csets are linked on their dom_csets to enable iteration of all threaded tasks. * cgroup->nr_threaded_children keeps track of the number of threaded children. This patch adds the above but doesn't actually use them yet. The following patches will build on top. v4: ->nr_threaded_children added. v3: ->proc_cgrp/cset renamed to ->dom_cgrp/cset. Updated for the new enable-threaded-per-cgroup behavior. v2: Added cgroup_is_threaded() helper. Signed-off-by: NTejun Heo <tj@kernel.org>
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由 Tejun Heo 提交于
css_task_iter currently always walks all tasks. With the scheduled cgroup v2 thread support, the iterator would need to handle multiple types of iteration. As a preparation, add @flags to css_task_iter_start() and implement CSS_TASK_ITER_PROCS. If the flag is not specified, it walks all tasks as before. When asserted, the iterator only walks the group leaders. For now, the only user of the flag is cgroup v2 "cgroup.procs" file which no longer needs to skip non-leader tasks in cgroup_procs_next(). Note that cgroup v1 "cgroup.procs" can't use the group leader walk as v1 "cgroup.procs" doesn't mean "list all thread group leaders in the cgroup" but "list all thread group id's with any threads in the cgroup". While at it, update cgroup_procs_show() to use task_pid_vnr() instead of task_tgid_vnr(). As the iteration guarantees that the function only sees group leaders, this doesn't change the output and will allow sharing the function for thread iteration. Signed-off-by: NTejun Heo <tj@kernel.org>
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由 Tejun Heo 提交于
Currently, writes "cgroup.procs" and "cgroup.tasks" files are all handled by __cgroup_procs_write() on both v1 and v2. This patch reoragnizes the write path so that there are common helper functions that different write paths use. While this somewhat increases LOC, the different paths are no longer intertwined and each path has more flexibility to implement different behaviors which will be necessary for the planned v2 thread support. v3: - Restructured so that cgroup_procs_write_permission() takes @src_cgrp and @dst_cgrp. v2: - Rolled in Waiman's task reference count fix. - Updated on top of nsdelegate changes. Signed-off-by: NTejun Heo <tj@kernel.org> Cc: Waiman Long <longman@redhat.com>
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- 17 7月, 2017 3 次提交
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由 Tejun Heo 提交于
Implement trivial cgroup_has_tasks() which tests whether cgrp->nr_populated_csets is zero and replace the explicit local populated test in cgroup_subtree_control(). This simplifies the code and cgroup_has_tasks() will be used in more places later. Signed-off-by: NTejun Heo <tj@kernel.org>
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由 Tejun Heo 提交于
cgrp->populated_cnt counts both local (the cgroup's populated css_sets) and subtree proper (populated children) so that it's only zero when the whole subtree, including self, is empty. This patch splits the counter into two so that local and children populated states are tracked separately. It allows finer-grained tests on the state of the hierarchy which will be used to replace css_set walking local populated test. Signed-off-by: NTejun Heo <tj@kernel.org>
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由 Tejun Heo 提交于
Signed-off-by: NTejun Heo <tj@kernel.org>
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- 29 6月, 2017 2 次提交
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由 Tejun Heo 提交于
Currently, cgroup only supports delegation to !root users and cgroup namespaces don't get any special treatments. This limits the usefulness of cgroup namespaces as they by themselves can't be safe delegation boundaries. A process inside a cgroup can change the resource control knobs of the parent in the namespace root and may move processes in and out of the namespace if cgroups outside its namespace are visible somehow. This patch adds a new mount option "nsdelegate" which makes cgroup namespaces delegation boundaries. If set, cgroup behaves as if write permission based delegation took place at namespace boundaries - writes to the resource control knobs from the namespace root are denied and migration crossing the namespace boundary aren't allowed from inside the namespace. This allows cgroup namespace to function as a delegation boundary by itself. v2: Silently ignore nsdelegate specified on !init mounts. Signed-off-by: NTejun Heo <tj@kernel.org> Cc: Aravind Anbudurai <aru7@fb.com> Cc: Serge Hallyn <serge@hallyn.com> Cc: Eric Biederman <ebiederm@xmission.com>
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由 Tejun Heo 提交于
Restructure cgroup_procs_write_permission() to make extending permission logic easier. This patch doesn't cause any functional changes. Signed-off-by: NTejun Heo <tj@kernel.org>
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- 15 6月, 2017 1 次提交
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由 Waiman Long 提交于
The reference count in the css_set data structure was used as a proxy of the number of tasks attached to that css_set. However, that count is actually not an accurate measure especially with thread mode support. So a new variable nr_tasks is added to the css_set to keep track of the actual task count. This new variable is protected by the css_set_lock. Functions that require the actual task count are updated to use the new variable. tj: s/task_count/nr_tasks/ for consistency with cgroup_root->nr_cgrps. Refreshed on top of cgroup/for-v4.13 which dropped on css_set_populated() -> nr_tasks conversion. Signed-off-by: NWaiman Long <longman@redhat.com> Signed-off-by: NTejun Heo <tj@kernel.org>
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- 18 5月, 2017 1 次提交
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由 Waiman Long 提交于
The kill_css() function may be called more than once under the condition that the css was killed but not physically removed yet followed by the removal of the cgroup that is hosting the css. This patch prevents any harmm from being done when that happens. Signed-off-by: NWaiman Long <longman@redhat.com> Signed-off-by: NTejun Heo <tj@kernel.org> Cc: stable@vger.kernel.org # v4.5+
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- 02 5月, 2017 1 次提交
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由 Tejun Heo 提交于
a590b90d ("cgroup: fix spurious warnings on cgroup_is_dead() from cgroup_sk_alloc()") converted most cgroup_get() usages to cgroup_get_live() leaving cgroup_sk_alloc() the sole user of cgroup_get(). When !CONFIG_SOCK_CGROUP_DATA, this ends up triggering unused warning for cgroup_get(). Silence the warning by adding __maybe_unused to cgroup_get(). Reported-by: NStephen Rothwell <sfr@canb.auug.org.au> Link: http://lkml.kernel.org/r/20170501145340.17e8ef86@canb.auug.org.auSigned-off-by: NTejun Heo <tj@kernel.org>
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- 29 4月, 2017 2 次提交
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由 Zefan Li 提交于
Commit bfb0b80d ("cgroup: avoid attaching a cgroup root to two different superblocks") is broken. Now we try to fix the race by delaying the initialization of cgroup root refcnt until a superblock has been allocated. Reported-by: NDmitry Vyukov <dvyukov@google.com> Reported-by: NAndrei Vagin <avagin@virtuozzo.com> Tested-by: NAndrei Vagin <avagin@virtuozzo.com> Signed-off-by: NZefan Li <lizefan@huawei.com> Signed-off-by: NTejun Heo <tj@kernel.org>
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由 Tejun Heo 提交于
cgroup_get() expected to be called only on live cgroups and triggers warning on a dead cgroup; however, cgroup_sk_alloc() may be called while cloning a socket which is left in an empty and removed cgroup and thus may legitimately duplicate its reference on a dead cgroup. This currently triggers the following warning spuriously. WARNING: CPU: 14 PID: 0 at kernel/cgroup.c:490 cgroup_get+0x55/0x60 ... [<ffffffff8107e123>] __warn+0xd3/0xf0 [<ffffffff8107e20e>] warn_slowpath_null+0x1e/0x20 [<ffffffff810ff465>] cgroup_get+0x55/0x60 [<ffffffff81106061>] cgroup_sk_alloc+0x51/0xe0 [<ffffffff81761beb>] sk_clone_lock+0x2db/0x390 [<ffffffff817cce06>] inet_csk_clone_lock+0x16/0xc0 [<ffffffff817e8173>] tcp_create_openreq_child+0x23/0x4b0 [<ffffffff818601a1>] tcp_v6_syn_recv_sock+0x91/0x670 [<ffffffff817e8b16>] tcp_check_req+0x3a6/0x4e0 [<ffffffff81861ba3>] tcp_v6_rcv+0x693/0xa00 [<ffffffff81837429>] ip6_input_finish+0x59/0x3e0 [<ffffffff81837cb2>] ip6_input+0x32/0xb0 [<ffffffff81837387>] ip6_rcv_finish+0x57/0xa0 [<ffffffff81837ac8>] ipv6_rcv+0x318/0x4d0 [<ffffffff817778c7>] __netif_receive_skb_core+0x2d7/0x9a0 [<ffffffff81777fa6>] __netif_receive_skb+0x16/0x70 [<ffffffff81778023>] netif_receive_skb_internal+0x23/0x80 [<ffffffff817787d8>] napi_gro_frags+0x208/0x270 [<ffffffff8168a9ec>] mlx4_en_process_rx_cq+0x74c/0xf40 [<ffffffff8168b270>] mlx4_en_poll_rx_cq+0x30/0x90 [<ffffffff81778b30>] net_rx_action+0x210/0x350 [<ffffffff8188c426>] __do_softirq+0x106/0x2c7 [<ffffffff81082bad>] irq_exit+0x9d/0xa0 [<ffffffff8188c0e4>] do_IRQ+0x54/0xd0 [<ffffffff8188a63f>] common_interrupt+0x7f/0x7f <EOI> [<ffffffff8173d7e7>] cpuidle_enter+0x17/0x20 [<ffffffff810bdfd9>] cpu_startup_entry+0x2a9/0x2f0 [<ffffffff8103edd1>] start_secondary+0xf1/0x100 This patch renames the existing cgroup_get() with the dead cgroup warning to cgroup_get_live() after cgroup_kn_lock_live() and introduces the new cgroup_get() which doesn't check whether the cgroup is live or dead. All existing cgroup_get() users except for cgroup_sk_alloc() are converted to use cgroup_get_live(). Fixes: d979a39d ("cgroup: duplicate cgroup reference when cloning sockets") Cc: stable@vger.kernel.org # v4.5+ Cc: Johannes Weiner <hannes@cmpxchg.org> Reported-by: NChris Mason <clm@fb.com> Signed-off-by: NTejun Heo <tj@kernel.org>
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- 17 3月, 2017 1 次提交
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由 Tejun Heo 提交于
Creation of a kthread goes through a couple interlocked stages between the kthread itself and its creator. Once the new kthread starts running, it initializes itself and wakes up the creator. The creator then can further configure the kthread and then let it start doing its job by waking it up. In this configuration-by-creator stage, the creator is the only one that can wake it up but the kthread is visible to userland. When altering the kthread's attributes from userland is allowed, this is fine; however, for cases where CPU affinity is critical, kthread_bind() is used to first disable affinity changes from userland and then set the affinity. This also prevents the kthread from being migrated into non-root cgroups as that can affect the CPU affinity and many other things. Unfortunately, the cgroup side of protection is racy. While the PF_NO_SETAFFINITY flag prevents further migrations, userland can win the race before the creator sets the flag with kthread_bind() and put the kthread in a non-root cgroup, which can lead to all sorts of problems including incorrect CPU affinity and starvation. This bug got triggered by userland which periodically tries to migrate all processes in the root cpuset cgroup to a non-root one. Per-cpu workqueue workers got caught while being created and ended up with incorrected CPU affinity breaking concurrency management and sometimes stalling workqueue execution. This patch adds task->no_cgroup_migration which disallows the task to be migrated by userland. kthreadd starts with the flag set making every child kthread start in the root cgroup with migration disallowed. The flag is cleared after the kthread finishes initialization by which time PF_NO_SETAFFINITY is set if the kthread should stay in the root cgroup. It'd be better to wait for the initialization instead of failing but I couldn't think of a way of implementing that without adding either a new PF flag, or sleeping and retrying from waiting side. Even if userland depends on changing cgroup membership of a kthread, it either has to be synchronized with kthread_create() or periodically repeat, so it's unlikely that this would break anything. v2: Switch to a simpler implementation using a new task_struct bit field suggested by Oleg. Signed-off-by: NTejun Heo <tj@kernel.org> Suggested-by: NOleg Nesterov <oleg@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Reported-and-debugged-by: NChris Mason <clm@fb.com> Cc: stable@vger.kernel.org # v4.3+ (we can't close the race on < v4.3) Signed-off-by: NTejun Heo <tj@kernel.org>
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- 10 3月, 2017 1 次提交
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由 Masahiro Yamada 提交于
Fix typos and add the following to the scripts/spelling.txt: disble||disable disbled||disabled I kept the TSL2563_INT_DISBLED in /drivers/iio/light/tsl2563.c untouched. The macro is not referenced at all, but this commit is touching only comment blocks just in case. Link: http://lkml.kernel.org/r/1481573103-11329-20-git-send-email-yamada.masahiro@socionext.comSigned-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 09 3月, 2017 1 次提交
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由 Elena Reshetova 提交于
refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: NElena Reshetova <elena.reshetova@intel.com> Signed-off-by: NHans Liljestrand <ishkamiel@gmail.com> Signed-off-by: NKees Cook <keescook@chromium.org> Signed-off-by: NDavid Windsor <dwindsor@gmail.com> Signed-off-by: NTejun Heo <tj@kernel.org>
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- 07 3月, 2017 1 次提交
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由 Elena Reshetova 提交于
refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: NElena Reshetova <elena.reshetova@intel.com> Signed-off-by: NHans Liljestrand <ishkamiel@gmail.com> Signed-off-by: NKees Cook <keescook@chromium.org> Signed-off-by: NDavid Windsor <dwindsor@gmail.com> Signed-off-by: NTejun Heo <tj@kernel.org>
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- 02 3月, 2017 1 次提交
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由 Ingo Molnar 提交于
We are going to split <linux/sched/task.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/task.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: NLinus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: NIngo Molnar <mingo@kernel.org>
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- 03 2月, 2017 1 次提交
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由 Tejun Heo 提交于
Along with the write access to the cgroup.procs or tasks file, cgroup has required the writer's euid, unless root, to match [s]uid of the target process or task. On cgroup v1, this is necessary because there's nothing preventing a delegatee from pulling in tasks or processes from all over the system. If a user has a cgroup subdirectory delegated to it, the user would have write access to the cgroup.procs or tasks file. If there are no further checks than file write access check, the user would be able to pull processes from all over the system into its subhierarchy which is clearly not the intended behavior. The matching [s]uid requirement partially prevents this problem by allowing a delegatee to pull in the processes that belongs to it. This isn't a sufficient protection however, because a user would still be able to jump processes across two disjoint sub-hierarchies that has been delegated to them. cgroup v2 resolves the issue by requiring the writer to have access to the common ancestor of the cgroup.procs file of the source and target cgroups. This confines each delegatee to their own sub-hierarchy proper and bases all permission decisions on the cgroup filesystem rather than having to pull in explicit uid matching. cgroup v2 has still been applying the matching [s]uid requirement just for historical reasons. On cgroup2, the requirement doesn't serve any purpose while unnecessarily complicating the permission model. Let's drop it. Signed-off-by: NTejun Heo <tj@kernel.org>
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- 31 1月, 2017 1 次提交
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由 Tejun Heo 提交于
* cgrp_dfl_implicit_ss_mask is ulong instead of u16 unlike other ss_masks. Make it a u16. * Move have_canfork_callback together with other callback ss_masks. Signed-off-by: NTejun Heo <tj@kernel.org>
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- 16 1月, 2017 3 次提交
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由 Tejun Heo 提交于
Currently, subsys->*attach() callbacks are called for all subsystems which are attached to the hierarchy on which the migration is taking place. With cgroup_migrate_prepare_dst() filtering out identity migrations, v1 hierarchies can avoid spurious ->*attach() callback invocations where the source and destination csses are identical; however, this isn't enough on v2 as only a subset of the attached controllers can be affected on controller enable/disable. While spurious ->*attach() invocations aren't critically broken, they're unnecessary overhead and can lead to temporary overcharges on certain controllers. Fix it by tracking which subsystems are affected by a migration and invoking ->*attach() callbacks only on those subsystems. Signed-off-by: NTejun Heo <tj@kernel.org> Acked-by: NZefan Li <lizefan@huawei.com>
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由 Tejun Heo 提交于
cgroup migration is performed in four steps - css_set preloading, addition of target tasks, actual migration, and clean up. A list named preloaded_csets is used to track the preloading. This is a bit too restricted and the code is already depending on the subtlety that all source css_sets appear before destination ones. Let's create struct cgroup_mgctx which keeps track of everything during migration. Currently, it has separate preload lists for source and destination csets and also embeds cgroup_taskset which is used during the actual migration. This moves struct cgroup_taskset definition to cgroup-internal.h. This patch doesn't cause any functional changes. Signed-off-by: NTejun Heo <tj@kernel.org> Acked-by: NZefan Li <lizefan@huawei.com>
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由 Tejun Heo 提交于
cgroup_taskset_add() was using list_add_tail() when for source csets but list_move_tail() for destination. As the operations are gated by list_empty() test, list_move_tail() is equivalent to list_add_tail() here. Use list_add_tail() too for destination csets too. This doesn't cause any functional changes. Signed-off-by: NTejun Heo <tj@kernel.org> Acked-by: NZefan Li <lizefan@huawei.com>
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- 28 12月, 2016 10 次提交
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由 Tejun Heo 提交于
kn->priv which is a void * is used as a RCU pointer by cgroup. When dereferencing it, it was passing kn->priv to rcu_derefreence() without casting it into a RCU pointer triggering address space mismatch warning from sparse. Fix them. Signed-off-by: NTejun Heo <tj@kernel.org> Reported-by: NFengguang Wu <fengguang.wu@intel.com> Acked-by: NAcked-by: Zefan Li <lizefan@huawei.com>
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由 Tejun Heo 提交于
get/put_css_set() get exposed in cgroup-internal.h in the process. Signed-off-by: NTejun Heo <tj@kernel.org> Acked-by: NAcked-by: Zefan Li <lizefan@huawei.com>
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由 Tejun Heo 提交于
Now that v1 functions are separated out, rename some functions for consistency. cgroup_dfl_base_files -> cgroup_base_files cgroup_legacy_base_files -> cgroup1_base_files cgroup_ssid_no_v1() -> cgroup1_ssid_disabled() cgroup_pidlist_destroy_all -> cgroup1_pidlist_destroy_all() cgroup_release_agent() -> cgroup1_release_agent() check_for_release() -> cgroup1_check_for_release() Signed-off-by: NTejun Heo <tj@kernel.org> Acked-by: NAcked-by: Zefan Li <lizefan@huawei.com>
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由 Tejun Heo 提交于
Now that the v1 mount code is split into separate functions, move them to kernel/cgroup/cgroup-v1.c along with the mount option handling code. As this puts all v1-only kernfs_syscall_ops in cgroup-v1.c, move cgroup1_kf_syscall_ops to cgroup-v1.c too. Signed-off-by: NTejun Heo <tj@kernel.org> Acked-by: NAcked-by: Zefan Li <lizefan@huawei.com>
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由 Tejun Heo 提交于
Currently, cgroup_kf_syscall_ops is shared by v1 and v2 and the specific methods test the version and take different actions. Split out v1 functions and put them in cgroup1_kf_syscall_ops and remove the now unnecessary explicit branches in specific methods. Signed-off-by: NTejun Heo <tj@kernel.org> Acked-by: NAcked-by: Zefan Li <lizefan@huawei.com>
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由 Tejun Heo 提交于
While sharing some mechanisms, the mount paths of v1 and v2 are substantially different. Their implementations were mixed in cgroup_mount(). This patch splits them out so that they're easier to follow and organize. This patch causes one functional change - the WARN_ON(new_sb) gets lost. This is because the actual mounting gets moved to cgroup_do_mount() and thus @new_sb is no longer accessible by default to cgroup1_mount(). While we can add it as an explicit out parameter to cgroup_do_mount(), this part of code hasn't changed and the warning hasn't triggered for quite a while. Dropping it should be fine. Signed-off-by: NTejun Heo <tj@kernel.org> Acked-by: NAcked-by: Zefan Li <lizefan@huawei.com>
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由 Tejun Heo 提交于
cgroup.c is getting too unwieldy. Let's move out cgroup v1 specific code along with the debug controller into kernel/cgroup/cgroup-v1.c. v2: cgroup_mutex and css_set_lock made available in cgroup-internal.h regardless of CONFIG_PROVE_RCU. Signed-off-by: NTejun Heo <tj@kernel.org> Acked-by: NAcked-by: Zefan Li <lizefan@huawei.com>
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由 Tejun Heo 提交于
They're growing to be too many and planned to get split further. Move them under their own directory. kernel/cgroup.c -> kernel/cgroup/cgroup.c kernel/cgroup_freezer.c -> kernel/cgroup/freezer.c kernel/cgroup_pids.c -> kernel/cgroup/pids.c kernel/cpuset.c -> kernel/cgroup/cpuset.c Signed-off-by: NTejun Heo <tj@kernel.org> Acked-by: NAcked-by: Zefan Li <lizefan@huawei.com>
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由 Tejun Heo 提交于
Reorder css_set fields so that they're roughly in the order of how hot they are. The rough order is 1. the actual csses 2. reference counter and the default cgroup pointer. 3. task lists and iterations 4. fields used during merge including css_set lookup 5. the rest Signed-off-by: NTejun Heo <tj@kernel.org> Acked-by: NAcked-by: Zefan Li <lizefan@huawei.com>
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由 Tejun Heo 提交于
cgroup_pid_fry() was added to mangle cgroup.procs pid listing order on v2 to make it clear that the output is not sorted. Now that v2 now uses a separate "cgroup.procs" read method, this is no longer used. Remove it. Signed-off-by: NTejun Heo <tj@kernel.org> Acked-by: NAcked-by: Zefan Li <lizefan@huawei.com>
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