- 23 4月, 2010 1 次提交
-
-
由 Benjamin Herrenschmidt 提交于
Due to recent load-balancer changes that delay the task migration to the next wakeup, the adaptive mutex spinning ends up in a live lock when the owner's CPU gets offlined because the cpu_online() check lives before the owner running check. This patch changes mutex_spin_on_owner() to return 0 (don't spin) in any case where we aren't sure about the owner struct validity or CPU number, and if the said CPU is offline. There is no point going back & re-evaluate spinning in corner cases like that, let's just go to sleep. Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <1271212509.13059.135.camel@pasglop> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
- 06 4月, 2010 1 次提交
-
-
由 Anton Blanchard 提交于
taskset on 2.6.34-rc3 fails on one of my ppc64 test boxes with the following error: sched_getaffinity(0, 16, 0x10029650030) = -1 EINVAL (Invalid argument) This box has 128 threads and 16 bytes is enough to cover it. Commit cd3d8031 (sched: sched_getaffinity(): Allow less than NR_CPUS length) is comparing this 16 bytes agains nr_cpu_ids. Fix it by comparing nr_cpu_ids to the number of bits in the cpumask we pass in. Signed-off-by: NAnton Blanchard <anton@samba.org> Reviewed-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Sharyathi Nagesh <sharyath@in.ibm.com> Cc: Ulrich Drepper <drepper@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Jack Steiner <steiner@sgi.com> Cc: Russ Anderson <rja@sgi.com> Cc: Mike Travis <travis@sgi.com> LKML-Reference: <20100406070218.GM5594@kryten> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
- 03 4月, 2010 1 次提交
-
-
由 Oleg Nesterov 提交于
Trivial typo fix. rq->migration_thread can be NULL after task_rq_unlock(), this is why we have "mt" which should be used instead. Signed-off-by: NOleg Nesterov <oleg@redhat.com> Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <20100330165829.GA18284@redhat.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
- 30 3月, 2010 1 次提交
-
-
由 Tejun Heo 提交于
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: NTejun Heo <tj@kernel.org> Guess-its-ok-by: NChristoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
-
- 17 3月, 2010 1 次提交
-
-
由 KOSAKI Motohiro 提交于
Using the proper type fixes the following compiler warning: kernel/sched.c:4850: warning: comparison of distinct pointer types lacks a cast Signed-off-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: torvalds@linux-foundation.org Cc: travis@sgi.com Cc: peterz@infradead.org Cc: drepper@redhat.com Cc: rja@sgi.com Cc: sharyath@in.ibm.com Cc: steiner@sgi.com LKML-Reference: <20100317090046.4C79.A69D9226@jp.fujitsu.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
- 16 3月, 2010 1 次提交
-
-
由 Andrew Morton 提交于
On UP: kernel/sched.c: In function 'wake_up_new_task': kernel/sched.c:2631: warning: unused variable 'cpu' Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
- 15 3月, 2010 1 次提交
-
-
由 KOSAKI Motohiro 提交于
[ Note, this commit changes the syscall ABI for > 1024 CPUs systems. ] Recently, some distro decided to use NR_CPUS=4096 for mysterious reasons. Unfortunately, glibc sched interface has the following definition: # define __CPU_SETSIZE 1024 # define __NCPUBITS (8 * sizeof (__cpu_mask)) typedef unsigned long int __cpu_mask; typedef struct { __cpu_mask __bits[__CPU_SETSIZE / __NCPUBITS]; } cpu_set_t; It mean, if NR_CPUS is bigger than 1024, cpu_set_t makes an ABI issue ... More recently, Sharyathi Nagesh reported following test program makes misterious syscall failure: ----------------------------------------------------------------------- #define _GNU_SOURCE #include<stdio.h> #include<errno.h> #include<sched.h> int main() { cpu_set_t set; if (sched_getaffinity(0, sizeof(cpu_set_t), &set) < 0) printf("\n Call is failing with:%d", errno); } ----------------------------------------------------------------------- Because the kernel assumes len argument of sched_getaffinity() is bigger than NR_CPUS. But now it is not correct. Now we are faced with the following annoying dilemma, due to the limitations of the glibc interface built in years ago: (1) if we change glibc's __CPU_SETSIZE definition, we lost binary compatibility of _all_ application. (2) if we don't change it, we also lost binary compatibility of Sharyathi's use case. Then, I would propse to change the rule of the len argument of sched_getaffinity(). Old: len should be bigger than NR_CPUS New: len should be bigger than maximum possible cpu id This creates the following behavior: (A) In the real 4096 cpus machine, the above test program still return -EINVAL. (B) NR_CPUS=4096 but the machine have less than 1024 cpus (almost all machines in the world), the above can run successfully. Fortunatelly, BIG SGI machine is mainly used for HPC use case. It means they can rebuild their programs. IOW we hope they are not annoyed by this issue ... Reported-by: NSharyathi Nagesh <sharyath@in.ibm.com> Signed-off-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Acked-by: NUlrich Drepper <drepper@redhat.com> Acked-by: NPeter Zijlstra <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Jack Steiner <steiner@sgi.com> Cc: Russ Anderson <rja@sgi.com> Cc: Mike Travis <travis@sgi.com> LKML-Reference: <20100312161316.9520.A69D9226@jp.fujitsu.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
- 11 3月, 2010 1 次提交
-
-
由 Dan Carpenter 提交于
We haven't used the "orig_rq" variable since 055a0086 "Fix/add missing update_rq_clock() calls" Signed-off-by: NDan Carpenter <error27@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Andreas Herrmann <andreas.herrmann3@amd.com> Cc: Gautham R Shenoy <ego@in.ibm.com> Cc: efault@gmx.de LKML-Reference: <20100306111752.GL4958@bicker> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
- 08 3月, 2010 1 次提交
-
-
由 Andi Kleen 提交于
Passing the attribute to the low level IO functions allows all kinds of cleanups, by sharing low level IO code without requiring an own function for every piece of data. Also drivers can extend the attributes with own data fields and use that in the low level function. Similar to sysdev_attributes and normal attributes. This is a tree-wide sweep, converting everything in one go. No functional changes in this patch other than passing the new argument everywhere. Tested on x86, the non x86 parts are uncompiled. Signed-off-by: NAndi Kleen <ak@linux.intel.com> Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
-
- 07 3月, 2010 1 次提交
-
-
由 Jiri Slaby 提交于
Make sure compiler won't do weird things with limits. E.g. fetching them twice may return 2 different values after writable limits are implemented. I.e. either use rlimit helpers added in commit 3e10e716 ("resource: add helpers for fetching rlimits") or ACCESS_ONCE if not applicable. Signed-off-by: NJiri Slaby <jslaby@suse.cz> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: john stultz <johnstul@us.ibm.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
- 25 2月, 2010 2 次提交
-
-
由 Paul E. McKenney 提交于
As suggested by Peter Ziljstra, make better choice of name for for_each_domain_rd(), containing "rcu_dereference", given that it is but a wrapper for rcu_dereference_check(). The name rcu_dereference_check_sched_domain() does that and provides a separate per-subsystem name space. Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: laijs@cn.fujitsu.com Cc: dipankar@in.ibm.com Cc: mathieu.desnoyers@polymtl.ca Cc: josh@joshtriplett.org Cc: dvhltc@us.ibm.com Cc: niv@us.ibm.com Cc: peterz@infradead.org Cc: rostedt@goodmis.org Cc: Valdis.Kletnieks@vt.edu Cc: dhowells@redhat.com LKML-Reference: <1266887105-1528-7-git-send-email-paulmck@linux.vnet.ibm.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Paul E. McKenney 提交于
Update the rcu_dereference() usages to take advantage of the new lockdep-based checking. Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: laijs@cn.fujitsu.com Cc: dipankar@in.ibm.com Cc: mathieu.desnoyers@polymtl.ca Cc: josh@joshtriplett.org Cc: dvhltc@us.ibm.com Cc: niv@us.ibm.com Cc: peterz@infradead.org Cc: rostedt@goodmis.org Cc: Valdis.Kletnieks@vt.edu Cc: dhowells@redhat.com LKML-Reference: <1266887105-1528-6-git-send-email-paulmck@linux.vnet.ibm.com> [ -v2: fix allmodconfig missing symbol export build failure on x86 ] Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
- 17 2月, 2010 2 次提交
-
-
由 Thomas Gleixner 提交于
setscheduler() saves task->sched_class outside of the rq->lock held region for a check after the setscheduler changes have become effective. That might result in checking a stale value. rtmutex_setprio() has the same problem, though it is protected by p->pi_lock against setscheduler(), but for correctness sake (and to avoid bad examples) it needs to be fixed as well. Retrieve task->sched_class inside of the rq->lock held region. Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Acked-by: NPeter Zijlstra <peterz@infradead.org> Cc: stable@kernel.org
-
由 Tejun Heo 提交于
Add __percpu sparse annotations to core subsystems. These annotations are to make sparse consider percpu variables to be in a different address space and warn if accessed without going through percpu accessors. This patch doesn't affect normal builds. Signed-off-by: NTejun Heo <tj@kernel.org> Reviewed-by: NChristoph Lameter <cl@linux-foundation.org> Acked-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: linux-mm@kvack.org Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Dipankar Sarma <dipankar@in.ibm.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Eric Biederman <ebiederm@xmission.com>
-
- 16 2月, 2010 2 次提交
-
-
由 Peter Zijlstra 提交于
Thomas found that due to ttwu() changing a task's cpu without holding the rq->lock, task_rq_lock() might end up locking the wrong rq. Avoid this by serializing against TASK_WAKING. Reported-by: NThomas Gleixner <tglx@linutronix.de> Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <1266241712.15770.420.camel@laptop> Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
-
由 Suresh Siddha 提交于
Fix a SMT scheduler performance regression that is leading to a scenario where SMT threads in one core are completely idle while both the SMT threads in another core (on the same socket) are busy. This is caused by this commit (with the problematic code highlighted) commit bdb94aa5 Author: Peter Zijlstra <a.p.zijlstra@chello.nl> Date: Tue Sep 1 10:34:38 2009 +0200 sched: Try to deal with low capacity @@ -4203,15 +4223,18 @@ find_busiest_queue() ... for_each_cpu(i, sched_group_cpus(group)) { + unsigned long power = power_of(i); ... - wl = weighted_cpuload(i); + wl = weighted_cpuload(i) * SCHED_LOAD_SCALE; + wl /= power; - if (rq->nr_running == 1 && wl > imbalance) + if (capacity && rq->nr_running == 1 && wl > imbalance) continue; On a SMT system, power of the HT logical cpu will be 589 and the scheduler load imbalance (for scenarios like the one mentioned above) can be approximately 1024 (SCHED_LOAD_SCALE). The above change of scaling the weighted load with the power will result in "wl > imbalance" and ultimately resulting in find_busiest_queue() return NULL, causing load_balance() to think that the load is well balanced. But infact one of the tasks can be moved to the idle core for optimal performance. We don't need to use the weighted load (wl) scaled by the cpu power to compare with imabalance. In that condition, we already know there is only a single task "rq->nr_running == 1" and the comparison between imbalance, wl is to make sure that we select the correct priority thread which matches imbalance. So we really need to compare the imabalnce with the original weighted load of the cpu and not the scaled load. But in other conditions where we want the most hammered(busiest) cpu, we can use scaled load to ensure that we consider the cpu power in addition to the actual load on that cpu, so that we can move the load away from the guy that is getting most hammered with respect to the actual capacity, as compared with the rest of the cpu's in that busiest group. Fix it. Reported-by: NMa Ling <ling.ma@intel.com> Initial-Analysis-by: NZhang, Yanmin <yanmin_zhang@linux.intel.com> Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <1266023662.2808.118.camel@sbs-t61.sc.intel.com> Cc: stable@kernel.org [2.6.32.x] Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
-
- 08 2月, 2010 2 次提交
-
-
由 Anton Blanchard 提交于
When CONFIG_VIRT_CPU_ACCOUNTING and CONFIG_CGROUP_CPUACCT are enabled we can call cpuacct_update_stats with values much larger than percpu_counter_batch. This means the call to percpu_counter_add will always add to the global count which is protected by a spinlock and we end up with a global spinlock in the scheduler. Based on an idea by KOSAKI Motohiro, this patch scales the batch value by cputime_one_jiffy such that we have the same batch limit as we would if CONFIG_VIRT_CPU_ACCOUNTING was disabled. His patch did this once at boot but that initialisation happened too early on PowerPC (before time_init) and it was never updated at runtime as a result of a hotplug cpu add/remove. This patch instead scales percpu_counter_batch by cputime_one_jiffy at runtime, which keeps the batch correct even after cpu hotplug operations. We cap it at INT_MAX in case of overflow. For architectures that do not support CONFIG_VIRT_CPU_ACCOUNTING, cputime_one_jiffy is the constant 1 and gcc is smart enough to optimise min(s32 percpu_counter_batch, INT_MAX) to just percpu_counter_batch at least on x86 and PowerPC. So there is no need to add an #ifdef. On a 64 thread PowerPC box with CONFIG_VIRT_CPU_ACCOUNTING and CONFIG_CGROUP_CPUACCT enabled, a context switch microbenchmark is 234x faster and almost matches a CONFIG_CGROUP_CPUACCT disabled kernel: CONFIG_CGROUP_CPUACCT disabled: 16906698 ctx switches/sec CONFIG_CGROUP_CPUACCT enabled: 61720 ctx switches/sec CONFIG_CGROUP_CPUACCT + patch: 16663217 ctx switches/sec Tested with: wget http://ozlabs.org/~anton/junkcode/context_switch.c make context_switch for i in `seq 0 63`; do taskset -c $i ./context_switch & done vmstat 1 Signed-off-by: NAnton Blanchard <anton@samba.org> Reviewed-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Acked-by: NBalbir Singh <balbir@linux.vnet.ibm.com> Tested-by: NBalbir Singh <balbir@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: "Luck, Tony" <tony.luck@intel.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Andrew Morton 提交于
On UP: kernel/sched.c: In function 'wake_up_new_task': kernel/sched.c:2631: warning: unused variable 'cpu' Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
- 04 2月, 2010 1 次提交
-
-
由 Yong Zhang 提交于
It's a duplicate of tg->rt_se[cpu] and the only usage is sched_rt_rq_dequeue() and sched_rt_rq_enqueue(). After the first patch to those two function. rt_se can be removed. Signed-off-by: NYong Zhang <yong.zhang0@gmail.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <2674af741001282258q38781619u653ca4a7dd267347@mail.gmail.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
- 02 2月, 2010 1 次提交
-
-
由 Peter Zijlstra 提交于
Commit f492e12e ("sched: Remove load_balance_newidle()") removed the only user of this function, so remove it too. Reported-by: NStephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <1265019219.24455.128.camel@laptop> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
- 23 1月, 2010 2 次提交
-
-
由 Thomas Gleixner 提交于
rtmutex_set_prio() is used to implement priority inheritance for futexes. When a task is deboosted it gets enqueued at the tail of its RT priority list. This is violating the POSIX scheduling semantics: rt priority list X contains two runnable tasks A and B task A runs with priority X and holds mutex M task C preempts A and is blocked on mutex M -> task A is boosted to priority of task C (Y) task A unlocks the mutex M and deboosts itself -> A is dequeued from rt priority list Y -> A is enqueued to the tail of rt priority list X task C schedules away task B runs This is wrong as task A did not schedule away and therefor violates the POSIX scheduling semantics. Enqueue the task to the head of the priority list instead. Reported-by: NMathias Weber <mathias.weber.mw1@roche.com> Reported-by: NCarsten Emde <cbe@osadl.org> Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Acked-by: NPeter Zijlstra <peterz@infradead.org> Tested-by: NCarsten Emde <cbe@osadl.org> Tested-by: NMathias Weber <mathias.weber.mw1@roche.com> LKML-Reference: <20100120171629.809074113@linutronix.de>
-
由 Thomas Gleixner 提交于
The ability of enqueueing a task to the head of a SCHED_FIFO priority list is required to fix some violations of POSIX scheduling policy. Extend the related functions with a "head" argument. Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Acked-by: NPeter Zijlstra <peterz@infradead.org> Tested-by: NCarsten Emde <cbe@osadl.org> Tested-by: NMathias Weber <mathias.weber.mw1@roche.com> LKML-Reference: <20100120171629.734886007@linutronix.de>
-
- 22 1月, 2010 1 次提交
-
-
由 Peter Zijlstra 提交于
There are a number of issues: 1) TASK_WAKING vs cgroup_clone (cpusets) copy_process(): sched_fork() child->state = TASK_WAKING; /* waiting for wake_up_new_task() */ if (current->nsproxy != p->nsproxy) ns_cgroup_clone() cgroup_clone() mutex_lock(inode->i_mutex) mutex_lock(cgroup_mutex) cgroup_attach_task() ss->can_attach() ss->attach() [ -> cpuset_attach() ] cpuset_attach_task() set_cpus_allowed_ptr(); while (child->state == TASK_WAKING) cpu_relax(); will deadlock the system. 2) cgroup_clone (cpusets) vs copy_process So even if the above would work we still have: copy_process(): if (current->nsproxy != p->nsproxy) ns_cgroup_clone() cgroup_clone() mutex_lock(inode->i_mutex) mutex_lock(cgroup_mutex) cgroup_attach_task() ss->can_attach() ss->attach() [ -> cpuset_attach() ] cpuset_attach_task() set_cpus_allowed_ptr(); ... p->cpus_allowed = current->cpus_allowed over-writing the modified cpus_allowed. 3) fork() vs hotplug if we unplug the child's cpu after the sanity check when the child gets attached to the task_list but before wake_up_new_task() shit will meet with fan. Solve all these issues by moving fork cpu selection into wake_up_new_task(). Reported-by: NSerge E. Hallyn <serue@us.ibm.com> Tested-by: NSerge E. Hallyn <serue@us.ibm.com> Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <1264106190.4283.1314.camel@laptop> Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
-
- 21 1月, 2010 4 次提交
-
-
由 Dhaval Giani 提交于
Remove the USER_SCHED feature. It has been scheduled to be removed in 2.6.34 as per http://marc.info/?l=linux-kernel&m=125728479022976&w=2Signed-off-by: NDhaval Giani <dhaval.giani@gmail.com> Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <1263990378.24844.3.camel@localhost> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Peter Zijlstra 提交于
Take out the sched_class methods for load-balancing. Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <new-submission> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Peter Zijlstra 提交于
Straight fwd code movement. Since non of the load-balance abstractions are used anymore, do away with them and simplify the code some. In preparation move the code around. Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <new-submission> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Yong Zhang 提交于
Assume A->B schedule is processing, if B have acquired BKL before and it need reschedule this time. Then on B's context, it will go to need_resched_nonpreemptible for reschedule. But at this time, prev and switch_count are related to A. It's wrong and will lead to incorrect scheduler statistics. Signed-off-by: NYong Zhang <yong.zhang0@gmail.com> Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <2674af741001102238w7b0ddcadref00d345e2181d11@mail.gmail.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
- 13 1月, 2010 1 次提交
-
-
由 Jamie Iles 提交于
perf_event_task_sched_in() expects interrupts to be disabled, but on architectures with __ARCH_WANT_INTERRUPTS_ON_CTXSW defined, this isn't true. If this is defined, disable irqs around the call in finish_task_switch(). Signed-off-by: NJamie Iles <jamie.iles@picochip.com> Acked-by: NPeter Zijlstra <peterz@infradead.org> Cc: Russell King - ARM Linux <linux@arm.linux.org.uk> LKML-Reference: <1262964453-27370-1-git-send-email-jamie.iles@picochip.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
- 28 12月, 2009 2 次提交
-
-
由 Simon Kagstrom 提交于
Fixes a warning when building with g++: warning: deprecated conversion from string constant to 'char*' And the file parameter use is constant, so mark it as such. Signed-off-by: NSimon Kagstrom <simon.kagstrom@netinsight.net> Cc: peterz@infradead.org LKML-Reference: <20091223110818.442d848e@marrow.netinsight.se> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Peter Zijlstra 提交于
Since we only ever schedule the local cpu, there is no need to pass the cpu number to the perf sched hooks. This micro-optimizes things a bit. Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <new-submission> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
- 23 12月, 2009 1 次提交
-
-
由 Peter Zijlstra 提交于
Effectively reverts 738d2be4. As demonstrated by Eric, we really need to call __set_task_cpu() early in the fork() path to properly initialize the various task state -- specifically the cgroup state through set_task_rq(). [ we could probably fix this by explicitly calling __set_task_cpu() from sched_fork(), but lets try that for the next cycle and simply revert to the old behaviour for now. ] Reported-by: NEric Paris <eparis@redhat.com> Tested-by: Eric Paris <eparis@redhat.com>, Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> Cc: efault@gmx.de LKML-Reference: <1261492999.4937.36.camel@laptop> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
- 21 12月, 2009 2 次提交
-
-
由 Peter Zijlstra 提交于
The hot-unplug kstopmachine usage does a wakeup after deactivating the cpu, hence we cannot use cpu_active() here but must rely on the good olde online. Reported-by: NSachin Sant <sachinp@in.ibm.com> Reported-by: NJens Axboe <jens.axboe@oracle.com> Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> Tested-by: NJens Axboe <jens.axboe@oracle.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> LKML-Reference: <1261326987.4314.24.camel@laptop> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Peter Zijlstra 提交于
Revert the braindead pr_* crap. (Commit 663997d4 "sched: Use pr_fmt() and pr_<level>()") It's dumb and causes stupid "sched: " strings all over the place. Signed-off-by: NPeter Zijlstra <peterz@infradead.org> Acked-by: NMike Galbraith <efault@gmx.de> Cc: Joe Perches <joe@perches.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> LKML-Reference: <1261315437.4314.6.camel@laptop> [ i dont mind the pr_*() patterns that much - but Peter dislikes them with a vengence. ] [ - v2: remove spurious diffstat from changelog :-/ ] Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
- 17 12月, 2009 7 次提交
-
-
由 Peter Zijlstra 提交于
There's a preemption race in the set_task_cpu() debug check in that when we get preempted after setting task->state we'd still be on the rq proper, but fail the test. Check for preempted tasks, since those are always on the RQ. Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <20091217121830.137155561@chello.nl> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Frederic Weisbecker 提交于
In practice, it is harmless to voluntarily sleep in a rcu_read_lock() section if we are running under preempt rcu, but it is illegal if we build a kernel running non-preemptable rcu. Currently, might_sleep() doesn't notice sleepable operations under rcu_read_lock() sections if we are running under preemptable rcu because preempt_count() is left untouched after rcu_read_lock() in this case. But we want developers who test their changes under such config to notice the "sleeping while atomic" issues. So we add rcu_read_lock_nesting to prempt_count() in might_sleep() checks. [ v2: Handle rcu-tiny ] Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com> Reviewed-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> LKML-Reference: <1260991265-8451-1-git-send-regression-fweisbec@gmail.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Ingo Molnar 提交于
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <20091216170517.807938893@chello.nl> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Peter Zijlstra 提交于
Rearrange code a bit now that its a simpler function. Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <20091216170518.269101883@chello.nl> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Peter Zijlstra 提交于
In order to remove the cfs_rq dependency from set_task_cpu() we need to ensure the task is cfs_rq invariant for all callsites. The simple approach is to substract cfs_rq->min_vruntime from se->vruntime on dequeue, and add cfs_rq->min_vruntime on enqueue. However, this has the downside of breaking FAIR_SLEEPERS since we loose the old vruntime as we only maintain the relative position. To solve this, we observe that we only migrate runnable tasks, we do this using deactivate_task(.sleep=0) and activate_task(.wakeup=0), therefore we can restrain the min_vruntime invariance to that state. The only other case is wakeup balancing, since we want to maintain the old vruntime we cannot make it relative on dequeue, but since we don't migrate inactive tasks, we can do so right before we activate it again. This is where we need the new pre-wakeup hook, we need to call this while still holding the old rq->lock. We could fold it into ->select_task_rq(), but since that has multiple callsites and would obfuscate the locking requirements, that seems like a fudge. This leaves the fork() case, simply make sure that ->task_fork() leaves the ->vruntime in a relative state. This covers all cases where set_task_cpu() gets called, and ensures it sees a relative vruntime. Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <20091216170518.191697025@chello.nl> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Peter Zijlstra 提交于
As will be apparent in the next patch, we need a pre wakeup hook for sched_fair task migration, hence rename the post wakeup hook and one pre wakeup. Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <20091216170518.114746117@chello.nl> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-
由 Peter Zijlstra 提交于
Since kthread_bind() lost its dependencies on sched.c, move it back where it came from. Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <20091216170518.039524041@chello.nl> Signed-off-by: NIngo Molnar <mingo@elte.hu>
-