aboutsummaryrefslogtreecommitdiffstats
path: root/include/linux/sched.h
Commit message (Collapse)AuthorAge
* remove task_ppid_nr_nsRoland McGrath2008-01-13
| | | | | | | | | | | | | | | | | | | task_ppid_nr_ns is called in three places. One of these should never have called it. In the other two, using it broke the existing semantics. This was presumably accidental. If the function had not been there, it would have been much more obvious to the eye that those patches were changing the behavior. We don't need this function. In task_state, the pid of the ptracer is not the ppid of the ptracer. In do_task_stat, ppid is the tgid of the real_parent, not its pid. I also moved the call outside of lock_task_sighand, since it doesn't need it. In sys_getppid, ppid is the tgid of the real_parent, not its pid. Signed-off-by: Roland McGrath <roland@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* sched: clean up, move __sched_text_start/end to sched.hIngo Molnar2007-11-28
| | | | | | | | | | move __sched_text_start/end to sched.h. No code changed: text data bss dec hex filename 26582 2310 28 28920 70f8 sched.o.before 26582 2310 28 28920 70f8 sched.o.after Signed-off-by: Ingo Molnar <mingo@elte.hu>
* sched: proper prototype for kernel/sched.c:migration_init()Adrian Bunk2007-11-09
| | | | | | | | | | | | This patch adds a proper prototype for migration_init() in include/linux/sched.h Since there's no point in always returning 0 to a caller that doesn't check the return value it also changes the function to return void. Signed-off-by: Adrian Bunk <bunk@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* sched: avoid large irq-latencies in smp-balancingPeter Zijlstra2007-11-09
| | | | | | | | | | | | | SMP balancing is done with IRQs disabled and can iterate the full rq. When rqs are large this can cause large irq-latencies. Limit the nr of iterations on each run. This fixes a scheduling latency regression reported by the -rt folks. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Steven Rostedt <rostedt@goodmis.org> Tested-by: Gregory Haskins <ghaskins@novell.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* sched: remove PREEMPT_RESTRICTIngo Molnar2007-11-09
| | | | | | | remove PREEMPT_RESTRICT. (this is a separate commit so that any regression related to the removal itself is bisectable) Signed-off-by: Ingo Molnar <mingo@elte.hu>
* sched: restore deterministic CPU accounting on powerpcPaul Mackerras2007-11-09
| | | | | | | | | | | | | | | | | | | | | | | | | | Since powerpc started using CONFIG_GENERIC_CLOCKEVENTS, the deterministic CPU accounting (CONFIG_VIRT_CPU_ACCOUNTING) has been broken on powerpc, because we end up counting user time twice: once in timer_interrupt() and once in update_process_times(). This fixes the problem by pulling the code in update_process_times that updates utime and stime into a separate function called account_process_tick. If CONFIG_VIRT_CPU_ACCOUNTING is not defined, there is a version of account_process_tick in kernel/timer.c that simply accounts a whole tick to either utime or stime as before. If CONFIG_VIRT_CPU_ACCOUNTING is defined, then arch code gets to implement account_process_tick. This also lets us simplify the s390 code a bit; it means that the s390 timer interrupt can now call update_process_times even when CONFIG_VIRT_CPU_ACCOUNTING is turned on, and can just implement a suitable account_process_tick(). account_process_tick() now takes the task_struct * as an argument. Tested both with and without CONFIG_VIRT_CPU_ACCOUNTING. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* sched: reintroduce the sched_min_granularity tunablePeter Zijlstra2007-11-09
| | | | | | | | | | | | | | | we lost the sched_min_granularity tunable to a clever optimization that uses the sched_latency/min_granularity ratio - but the ratio is quite unintuitive to users and can also crash the kernel if the ratio is set to 0. So reintroduce the min_granularity tunable, while keeping the ratio maintained internally. no functionality changed. [ mingo@elte.hu: some fixlets. ] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* sched: fix /proc/<PID>/stat stime/utime monotonicity, part 2Balbir Singh2007-10-29
| | | | | | | | | Extend Peter's patch to fix accounting issues, by keeping stime monotonic too. Signed-off-by: Balbir Singh <balbir@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Tested-by: Frans Pop <elendil@planet.nl>
* sched: keep utime/stime monotonicPeter Zijlstra2007-10-29
| | | | | | | | | | | keep utime/stime monotonic. cpustats use utime/stime as a ratio against sum_exec_runtime, as a consequence it can happen - when the ratio changes faster than time accumulates - that either can be appear to go backwards. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* De-constify sched.hAlexey Dobriyan2007-10-26
| | | | | | | | | | | | | | | [PATCH] De-constify sched.h This reverts commit a8972ccf00b7184a743eb6cd9bc7f3443357910c ("sched: constify sched.h") 1) Patch doesn't change any code here, so gcc is already smart enough to "feel" constness in such simple functions. 2) There is no such thing as const task_struct. Anyone who think otherwise deserves compiler warning. Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* sched: isolate SMP balancing code a bit morePeter Williams2007-10-24
| | | | | | | | | | | | | | | At the moment, a lot of load balancing code that is irrelevant to non SMP systems gets included during non SMP builds. This patch addresses this issue and reduces the binary size on non SMP systems: text data bss dec hex filename 10983 28 1192 12203 2fab sched.o.before 10739 28 1192 11959 2eb7 sched.o.after Signed-off-by: Peter Williams <pwil3058@bigpond.net.au> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* sched: reduce balance-tasks overheadPeter Williams2007-10-24
| | | | | | | | | | | | | | | At the moment, balance_tasks() provides low level functionality for both move_tasks() and move_one_task() (indirectly) via the load_balance() function (in the sched_class interface) which also provides dual functionality. This dual functionality complicates the interfaces and internal mechanisms and makes the run time overhead of operations that are called with two run queue locks held. This patch addresses this issue and reduces the overhead of these operations. Signed-off-by: Peter Williams <pwil3058@bigpond.net.au> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* sched: constify sched.hJoe Perches2007-10-24
| | | | | | | Add const to some struct task_struct * uses Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* Isolate the explicit usage of signal->pgrpPavel Emelyanov2007-10-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The pgrp field is not used widely around the kernel so it is now marked as deprecated with appropriate comment. The initialization of INIT_SIGNALS is trimmed because a) they are set to 0 automatically; b) gcc cannot properly initialize two anonymous (the second one is the one with the session) unions. In this particular case to make it compile we'd have to add some field initialized right before the .pgrp. This is the same patch as the 1ec320afdc9552c92191d5f89fcd1ebe588334ca one (from Cedric), but for the pgrp field. Some progress report: We have to deprecate the pid, tgid, session and pgrp fields on struct task_struct and struct signal_struct. The session and pgrp are already deprecated. The tgid value is close to being such - the worst known usage in in fs/locks.c and audit code. The pid field deprecation is mainly blocked by numerous printk-s around the kernel that print the tsk->pid to log. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Cc: Oleg Nesterov <oleg@tv-sign.ru> Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Cc: Serge Hallyn <serue@us.ibm.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Herbert Poetzl <herbert@13thfloor.at> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* cpuset sched_load_balance flagPaul Jackson2007-10-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a new per-cpuset flag called 'sched_load_balance'. When enabled in a cpuset (the default value) it tells the kernel scheduler that the scheduler should provide the normal load balancing on the CPUs in that cpuset, sometimes moving tasks from one CPU to a second CPU if the second CPU is less loaded and if that task is allowed to run there. When disabled (write "0" to the file) then it tells the kernel scheduler that load balancing is not required for the CPUs in that cpuset. Now even if this flag is disabled for some cpuset, the kernel may still have to load balance some or all the CPUs in that cpuset, if some overlapping cpuset has its sched_load_balance flag enabled. If there are some CPUs that are not in any cpuset whose sched_load_balance flag is enabled, the kernel scheduler will not load balance tasks to those CPUs. Moreover the kernel will partition the 'sched domains' (non-overlapping sets of CPUs over which load balancing is attempted) into the finest granularity partition that it can find, while still keeping any two CPUs that are in the same shed_load_balance enabled cpuset in the same element of the partition. This serves two purposes: 1) It provides a mechanism for real time isolation of some CPUs, and 2) it can be used to improve performance on systems with many CPUs by supporting configurations in which load balancing is not done across all CPUs at once, but rather only done in several smaller disjoint sets of CPUs. This mechanism replaces the earlier overloading of the per-cpuset flag 'cpu_exclusive', which overloading was removed in an earlier patch: cpuset-remove-sched-domain-hooks-from-cpusets See further the Documentation and comments in the code itself. [akpm@linux-foundation.org: don't be weird] Signed-off-by: Paul Jackson <pj@sgi.com> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Uninline the task_xid_nr_ns() callsPavel Emelyanov2007-10-19
| | | | | | | | | | | | | | | | | | Since these are expanded into call to pid_nr_ns() anyway, it's OK to move the whole routine out-of-line. This is a cheap way to save ~100 bytes from vmlinux. Together with the previous two patches, it saves half-a-kilo from the vmlinux. Un-inline other (currently inlined) functions must be done with additional performance testing. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com> Cc: Oleg Nesterov <oleg@tv-sign.ru> Cc: Paul Menage <menage@google.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Isolate some explicit usage of task->tgidPavel Emelyanov2007-10-19
| | | | | | | | | | | | | | | | | | | | With pid namespaces this field is now dangerous to use explicitly, so hide it behind the helpers. Also the pid and pgrp fields o task_struct and signal_struct are to be deprecated. Unfortunately this patch cannot be sent right now as this leads to tons of warnings, so start isolating them, and deprecate later. Actually the p->tgid == pid has to be changed to has_group_leader_pid(), but Oleg pointed out that in case of posix cpu timers this is the same, and thread_group_leader() is more preferable. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Acked-by: Oleg Nesterov <oleg@tv-sign.ru> Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Uninline find_task_by_xxx set of functionsPavel Emelyanov2007-10-19
| | | | | | | | | | | | | | | | | | | | | | | | The find_task_by_something is a set of macros are used to find task by pid depending on what kind of pid is proposed - global or virtual one. All of them are wrappers above the most generic one - find_task_by_pid_type_ns() - and just substitute some args for it. It turned out, that dereferencing the current->nsproxy->pid_ns construction and pushing one more argument on the stack inline cause kernel text size to grow. This patch moves all this stuff out-of-line into kernel/pid.c. Together with the next patch it saves a bit less than 400 bytes from the .text section. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com> Cc: Oleg Nesterov <oleg@tv-sign.ru> Cc: Paul Menage <menage@google.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* pid namespaces: allow cloning of new namespacePavel Emelyanov2007-10-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When clone() is invoked with CLONE_NEWPID, create a new pid namespace and then create a new struct pid for the new process. Allocate pid_t's for the new process in the new pid namespace and all ancestor pid namespaces. Make the newly cloned process the session and process group leader. Since the active pid namespace is special and expected to be the first entry in pid->upid_list, preserve the order of pid namespaces. The size of 'struct pid' is dependent on the the number of pid namespaces the process exists in, so we use multiple pid-caches'. Only one pid cache is created during system startup and this used by processes that exist only in init_pid_ns. When a process clones its pid namespace, we create additional pid caches as necessary and use the pid cache to allocate 'struct pids' for that depth. Note, that with this patch the newly created namespace won't work, since the rest of the kernel still uses global pids, but this is to be fixed soon. Init pid namespace still works. [oleg@tv-sign.ru: merge fix] Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com> Cc: Paul Menage <menage@google.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Oleg Nesterov <oleg@tv-sign.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* pid namespaces: miscellaneous preparations for pid namespacesPavel Emelyanov2007-10-19
| | | | | | | | | | | | | | | * remove pid.h from pid_namespaces.h; * rework is_(cgroup|global)_init; * optimize (get|put)_pid_ns for init_pid_ns; * declare task_child_reaper to return actual reaper. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Cc: Oleg Nesterov <oleg@tv-sign.ru> Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com> Cc: Paul Menage <menage@google.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* pid namespaces: helpers to find the task by its numerical idsPavel Emelyanov2007-10-19
| | | | | | | | | | | | | | | | When searching the task by numerical id on may need to find it using global pid (as it is done now in kernel) or by its virtual id, e.g. when sending a signal to a task from one namespace the sender will specify the task's virtual id and we should find the task by this value. [akpm@linux-foundation.org: fix gfs2 linkage] Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Cc: Oleg Nesterov <oleg@tv-sign.ru> Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com> Cc: Paul Menage <menage@google.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* pid namespaces: helpers to obtain pid numbersPavel Emelyanov2007-10-19
| | | | | | | | | | | | | | | | | When showing pid to user or getting the pid numerical id for in-kernel use the value of this id may differ depending on the namespace. This set of helpers is used to get the global pid nr, the virtual (i.e. seen by task in its namespace) nr and the nr as it is seen from the specified namespace. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Cc: Oleg Nesterov <oleg@tv-sign.ru> Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com> Cc: Paul Menage <menage@google.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* pid namespaces: define is_global_init() and is_container_init()Serge E. Hallyn2007-10-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | is_init() is an ambiguous name for the pid==1 check. Split it into is_global_init() and is_container_init(). A cgroup init has it's tsk->pid == 1. A global init also has it's tsk->pid == 1 and it's active pid namespace is the init_pid_ns. But rather than check the active pid namespace, compare the task structure with 'init_pid_ns.child_reaper', which is initialized during boot to the /sbin/init process and never changes. Changelog: 2.6.22-rc4-mm2-pidns1: - Use 'init_pid_ns.child_reaper' to determine if a given task is the global init (/sbin/init) process. This would improve performance and remove dependence on the task_pid(). 2.6.21-mm2-pidns2: - [Sukadev Bhattiprolu] Changed is_container_init() calls in {powerpc, ppc,avr32}/traps.c for the _exception() call to is_global_init(). This way, we kill only the cgroup if the cgroup's init has a bug rather than force a kernel panic. [akpm@linux-foundation.org: fix comment] [sukadev@us.ibm.com: Use is_global_init() in arch/m32r/mm/fault.c] [bunk@stusta.de: kernel/pid.c: remove unused exports] [sukadev@us.ibm.com: Fix capability.c to work with threaded init] Signed-off-by: Serge E. Hallyn <serue@us.ibm.com> Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com> Acked-by: Pavel Emelianov <xemul@openvz.org> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Herbert Poetzel <herbert@13thfloor.at> Cc: Kirill Korotaev <dev@sw.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* pid namespaces: round up the APIPavel Emelianov2007-10-19
| | | | | | | | | | | | | | | | | | | | | | | | | | The set of functions process_session, task_session, process_group and task_pgrp is confusing, as the names can be mixed with each other when looking at the code for a long time. The proposals are to * equip the functions that return the integer with _nr suffix to represent that fact, * and to make all functions work with task (not process) by making the common prefix of the same name. For monotony the routines signal_session() and set_signal_session() are replaced with task_session_nr() and set_task_session(), especially since they are only used with the explicit task->signal dereference. Signed-off-by: Pavel Emelianov <xemul@openvz.org> Acked-by: Serge E. Hallyn <serue@us.ibm.com> Cc: Kirill Korotaev <dev@openvz.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Cc: Herbert Poetzl <herbert@13thfloor.at> Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Task Control Groups: make cpusets a client of cgroupsPaul Menage2007-10-19
| | | | | | | | | | | | | | | | | | | | | | Remove the filesystem support logic from the cpusets system and makes cpusets a cgroup subsystem The "cpuset" filesystem becomes a dummy filesystem; attempts to mount it get passed through to the cgroup filesystem with the appropriate options to emulate the old cpuset filesystem behaviour. Signed-off-by: Paul Menage <menage@google.com> Cc: Serge E. Hallyn <serue@us.ibm.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Paul Jackson <pj@sgi.com> Cc: Kirill Korotaev <dev@openvz.org> Cc: Herbert Poetzl <herbert@13thfloor.at> Cc: Srivatsa Vaddagiri <vatsa@in.ibm.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Task Control Groups: shared cgroup subsystem group arraysPaul Menage2007-10-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Replace the struct css_set embedded in task_struct with a pointer; all tasks that have the same set of memberships across all hierarchies will share a css_set object, and will be linked via their css_sets field to the "tasks" list_head in the css_set. Assuming that many tasks share the same cgroup assignments, this reduces overall space usage and keeps the size of the task_struct down (three pointers added to task_struct compared to a non-cgroups kernel, no matter how many subsystems are registered). [akpm@linux-foundation.org: fix a printk] [akpm@linux-foundation.org: build fix] Signed-off-by: Paul Menage <menage@google.com> Cc: Serge E. Hallyn <serue@us.ibm.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Paul Jackson <pj@sgi.com> Cc: Kirill Korotaev <dev@openvz.org> Cc: Herbert Poetzl <herbert@13thfloor.at> Cc: Srivatsa Vaddagiri <vatsa@in.ibm.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Cc: Serge E. Hallyn <serue@us.ibm.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Paul Jackson <pj@sgi.com> Cc: Kirill Korotaev <dev@openvz.org> Cc: Herbert Poetzl <herbert@13thfloor.at> Cc: Srivatsa Vaddagiri <vatsa@in.ibm.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Task Control Groups: basic task cgroup frameworkPaul Menage2007-10-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Generic Process Control Groups -------------------------- There have recently been various proposals floating around for resource management/accounting and other task grouping subsystems in the kernel, including ResGroups, User BeanCounters, NSProxy cgroups, and others. These all need the basic abstraction of being able to group together multiple processes in an aggregate, in order to track/limit the resources permitted to those processes, or control other behaviour of the processes, and all implement this grouping in different ways. This patchset provides a framework for tracking and grouping processes into arbitrary "cgroups" and assigning arbitrary state to those groupings, in order to control the behaviour of the cgroup as an aggregate. The intention is that the various resource management and virtualization/cgroup efforts can also become task cgroup clients, with the result that: - the userspace APIs are (somewhat) normalised - it's easier to test e.g. the ResGroups CPU controller in conjunction with the BeanCounters memory controller, or use either of them as the resource-control portion of a virtual server system. - the additional kernel footprint of any of the competing resource management systems is substantially reduced, since it doesn't need to provide process grouping/containment, hence improving their chances of getting into the kernel This patch: Add the main task cgroups framework - the cgroup filesystem, and the basic structures for tracking membership and associating subsystem state objects to tasks. Signed-off-by: Paul Menage <menage@google.com> Cc: Serge E. Hallyn <serue@us.ibm.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Paul Jackson <pj@sgi.com> Cc: Kirill Korotaev <dev@openvz.org> Cc: Herbert Poetzl <herbert@13thfloor.at> Cc: Srivatsa Vaddagiri <vatsa@in.ibm.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/mingo/linux-2.6-schedLinus Torvalds2007-10-18
|\ | | | | | | | | | | | | | | | | * git://git.kernel.org/pub/scm/linux/kernel/git/mingo/linux-2.6-sched: sched: reduce schedstat variable overhead a bit sched: add KERN_CONT annotation sched: cleanup, make struct rq comments more consistent sched: cleanup, fix spacing sched: fix return value of wait_for_completion_interruptible()
| * sched: reduce schedstat variable overhead a bitKen Chen2007-10-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | schedstat is useful in investigating CPU scheduler behavior. Ideally, I think it is beneficial to have it on all the time. However, the cost of turning it on in production system is quite high, largely due to number of events it collects and also due to its large memory footprint. Most of the fields probably don't need to be full 64-bit on 64-bit arch. Rolling over 4 billion events will most like take a long time and user space tool can be made to accommodate that. I'm proposing kernel to cut back most of variable width on 64-bit system. (note, the following patch doesn't affect 32-bit system). Signed-off-by: Ken Chen <kenchen@google.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | Add scaled time to taskstats based process accountingMichael Neuling2007-10-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds items to the taststats struct to account for user and system time based on scaling the CPU frequency and instruction issue rates. Adds account_(user|system)_time_scaled callbacks which architectures can use to account for time using this mechanism. Signed-off-by: Michael Neuling <mikey@neuling.org> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Jay Lan <jlan@engr.sgi.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Remove struct task_struct::io_waitAlexey Dobriyan2007-10-18
|/ | | | | | | | | | | | Hell knows what happened in commit 63b05203af57e7de4f3bb63b8b81d43bc196d32b during 2.6.9 development. Commit introduced io_wait field which remained write-only than and still remains write-only. Also garbage collect macros which "use" io_wait. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/mingo/linux-2.6-schedLinus Torvalds2007-10-17
|\ | | | | | | | | | | | | | | * git://git.kernel.org/pub/scm/linux/kernel/git/mingo/linux-2.6-sched: sched: fix new task startup crash sched: fix !SYSFS build breakage sched: fix improper load balance across sched domain sched: more robust sd-sysctl entry freeing
| * sched: fix !SYSFS build breakageDhaval Giani2007-10-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When CONFIG_SYSFS is not set, CONFIG_FAIR_USER_SCHED fails to build with kernel/built-in.o: In function `uids_kobject_init': (.init.text+0x1488): undefined reference to `kernel_subsys' kernel/built-in.o: In function `uids_kobject_init': (.init.text+0x1490): undefined reference to `kernel_subsys' kernel/built-in.o: In function `uids_kobject_init': (.init.text+0x1480): undefined reference to `kernel_subsys' kernel/built-in.o: In function `uids_kobject_init': (.init.text+0x1494): undefined reference to `kernel_subsys' This patch fixes this build error. Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com> Signed-off-by: Dhaval Giani <dhaval@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | ifdef struct task_struct::securityAlexey Dobriyan2007-10-17
| | | | | | | | | | | | | | | | | | | | | | | | For those who don't care about CONFIG_SECURITY. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: "Serge E. Hallyn" <serge@hallyn.com> Cc: Casey Schaufler <casey@schaufler-ca.com> Cc: James Morris <jmorris@namei.org> Cc: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | task_struct: move ->fpu_counter and ->oomkilladjAlexey Dobriyan2007-10-17
| | | | | | | | | | | | | | | | | | | | There is nice 2 byte hole after struct task_struct::ioprio field into which we can put two 1-byte fields: ->fpu_counter and ->oomkilladj. Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru> Acked-by: Arjan van de Ven <arjan@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | user.c: #ifdef ->mq_bytesAlexey Dobriyan2007-10-17
| | | | | | | | | | | | | | | | | | | | | | | | For those who deselect POSIX message queues. Reduces SLAB size of user_struct from 64 to 32 bytes here, SLUB size -- from 40 bytes to 32 bytes. [akpm@linux-foundation.org: fix build] Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Shrink task_struct if CONFIG_FUTEX=nAlexey Dobriyan2007-10-17
| | | | | | | | | | | | | | | | | | | | robust_list, compat_robust_list, pi_state_list, pi_state_cache are really used if futexes are on. Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Shrink struct task_struct::oomkilladjAlexey Dobriyan2007-10-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | oomkilladj is int, but values which can be assigned to it are -17, [-16, 15], thus fitting into s8. While patch itself doesn't help in making task_struct smaller, because of natural alignment of ->link_count, it will make picture clearer wrt futher task_struct reduction patches. My plan is to move ->fpu_counter and ->oomkilladj after ->ioprio filling hole on i386 and x86_64. But that's for later, because bloated distro configs need looking at as well. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Add MMF_DUMP_ELF_HEADERSRoland McGrath2007-10-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds the MMF_DUMP_ELF_HEADERS option to /proc/pid/coredump_filter. This dumps the first page (only) of a private file mapping if it appears to be a mapping of an ELF file. Including these pages in the core dump may give sufficient identifying information to associate the original DSO and executable file images and their debugging information with a core file in a generic way just from its contents (e.g. when those binaries were built with ld --build-id). I expect this to become the default behavior eventually. Existing versions of gdb can be confused by the core dumps it creates, so it won't enabled by default for some time to come. Soon many people will have systems with a gdb that handle these dumps, so they can arrange to set the bit at boot and have it inherited system-wide. This also cleans up the checking of the MMF_DUMP_* flag bits, which did not need to be using atomic macros. Signed-off-by: Roland McGrath <roland@redhat.com> Cc: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | softlockup: add a /proc tuning parameterRavikiran G Thirumalai2007-10-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Control the trigger limit for softlockup warnings. This is useful for debugging softlockups, by lowering the softlockup_thresh to identify possible softlockups earlier. This patch: 1. Adds a sysctl softlockup_thresh with valid values of 1-60s (Higher value to disable false positives) 2. Changes the softlockup printk to print the cpu softlockup time [akpm@linux-foundation.org: Fix various warnings and add definition of "two"] Signed-off-by: Ravikiran Thirumalai <kiran@scalex86.org> Signed-off-by: Shai Fultheim <shai@scalex86.org> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | mm: dirty balancing for tasksPeter Zijlstra2007-10-17
|/ | | | | | | | | | | | | | | | | | | | Based on ideas of Andrew: http://marc.info/?l=linux-kernel&m=102912915020543&w=2 Scale the bdi dirty limit inversly with the tasks dirty rate. This makes heavy writers have a lower dirty limit than the occasional writer. Andrea proposed something similar: http://lwn.net/Articles/152277/ The main disadvantage to his patch is that he uses an unrelated quantity to measure time, which leaves him with a workload dependant tunable. Other than that the two approaches appear quite similar. [akpm@linux-foundation.org: fix warning] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* cpuset: remove sched domain hooks from cpusetsPaul Jackson2007-10-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Remove the cpuset hooks that defined sched domains depending on the setting of the 'cpu_exclusive' flag. The cpu_exclusive flag can only be set on a child if it is set on the parent. This made that flag painfully unsuitable for use as a flag defining a partitioning of a system. It was entirely unobvious to a cpuset user what partitioning of sched domains they would be causing when they set that one cpu_exclusive bit on one cpuset, because it depended on what CPUs were in the remainder of that cpusets siblings and child cpusets, after subtracting out other cpu_exclusive cpusets. Furthermore, there was no way on production systems to query the result. Using the cpu_exclusive flag for this was simply wrong from the get go. Fortunately, it was sufficiently borked that so far as I know, almost no successful use has been made of this. One real time group did use it to affectively isolate CPUs from any load balancing efforts. They are willing to adapt to alternative mechanisms for this, such as someway to manipulate the list of isolated CPUs on a running system. They can do without this present cpu_exclusive based mechanism while we develop an alternative. There is a real risk, to the best of my understanding, of users accidentally setting up a partitioned scheduler domains, inhibiting desired load balancing across all their CPUs, due to the nonobvious (from the cpuset perspective) side affects of the cpu_exclusive flag. Furthermore, since there was no way on a running system to see what one was doing with sched domains, this change will be invisible to any using code. Unless they have real insight to the scheduler load balancing choices, they will be unable to detect that this change has been made in the kernel's behaviour. Initial discussion on lkml of this patch has generated much comment. My (probably controversial) take on that discussion is that it has reached a rough concensus that the current cpuset cpu_exclusive mechanism for defining sched domains is borked. There is no concensus on the replacement. But since we can remove this mechanism, and since its continued presence risks causing unwanted partitioning of the schedulers load balancing, we should remove it while we can, as we proceed to work the replacement scheduler domain mechanisms. Signed-off-by: Paul Jackson <pj@sgi.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Cc: Christoph Lameter <clameter@engr.sgi.com> Cc: Dinakar Guniguntala <dino@in.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* move mm_struct and vm_area_structMartin Schwidefsky2007-10-16
| | | | | | | | | | | | | Move the definitions of struct mm_struct and struct vma_area_struct to include/mm_types.h. This allows to define more function in asm/pgtable.h and friends with inline assemblies instead of macros. Compile tested on i386, powerpc, powerpc64, s390-32, s390-64 and x86_64. [aurelien@aurel32.net: build fix] Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Aurelien Jarno <aurelien@aurel32.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* sched: guest CPU accounting: maintain stats in account_system_time()Laurent Vivier2007-10-15
| | | | | | | | | | | | | | | modify account_system_time() to add cputime to cpustat->guest if we are running a VCPU. We add this cputime to cpustat->user instead of cpustat->system because this part of KVM code is in fact user code although it is executed in the kernel. We duplicate VCPU time between guest and user to allow an unmodified "top(1)" to display correct value. A modified "top(1)" is able to display good cpu user time and cpu guest time by subtracting cpu guest time from cpu user time. Update "gtime" in task_struct accordingly. Signed-off-by: Laurent Vivier <Laurent.Vivier@bull.net> Acked-by: Avi Kivity <avi@qumranet.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* sched: guest CPU accounting: add guest-CPU /proc/<pid>/stat fieldsLaurent Vivier2007-10-15
| | | | | | | | | | | | like for cpustat, introduce the "gtime" (guest time of the task) and "cgtime" (guest time of the task children) fields for the tasks. Modify signal_struct and task_struct. Modify /proc/<pid>/stat to display these new fields. Signed-off-by: Laurent Vivier <Laurent.Vivier@bull.net> Acked-by: Avi Kivity <avi@qumranet.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* sched: debug, improve migration statisticsIngo Molnar2007-10-15
| | | | | | | add new migration statistics when SCHED_DEBUG and SCHEDSTATS is enabled. Available in /proc/<PID>/sched. Signed-off-by: Ingo Molnar <mingo@elte.hu>
* sched: reintroduce cache-hot affinityIngo Molnar2007-10-15
| | | | | | | | reintroduce a simplified version of cache-hot/cold scheduling affinity. This improves performance with certain SMP workloads, such as sysbench. Signed-off-by: Ingo Molnar <mingo@elte.hu>
* sched: prevent wakeup over-schedulingMike Galbraith2007-10-15
| | | | | | | | | | | Prevent wakeup over-scheduling. Once a task has been preempted by a task of the same or lower priority, it becomes ineligible for repeated preemption by same until it has been ticked, or slept. Instead, the task is marked for preemption at the next tick. Tasks of higher priority still preempt immediately. Signed-off-by: Mike Galbraith <efault@gmx.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* sched: group scheduling, sysfs tunablesDhaval Giani2007-10-15
| | | | | | | | | | | | | | | | | | | | | | | | | Add tunables in sysfs to modify a user's cpu share. A directory is created in sysfs for each new user in the system. /sys/kernel/uids/<uid>/cpu_share Reading this file returns the cpu shares granted for the user. Writing into this file modifies the cpu share for the user. Only an administrator is allowed to modify a user's cpu share. Ex: # cd /sys/kernel/uids/ # cat 512/cpu_share 1024 # echo 2048 > 512/cpu_share # cat 512/cpu_share 2048 # Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com> Signed-off-by: Dhaval Giani <dhaval@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* sched: cleanup: rename task_grp to task_groupIngo Molnar2007-10-15
| | | | | | | cleanup: rename task_grp to task_group. No need to save two characters and 'grp' is annoying to read. Signed-off-by: Ingo Molnar <mingo@elte.hu>