summaryrefslogtreecommitdiffstats
path: root/kernel
Commit message (Collapse)AuthorAgeFilesLines
* kernel/sys.c: fix "warning: do-while statement is not a compound statement" ↵H Hartley Sweeten2009-12-151-4/+4
| | | | | | | | | | | | | | | | | | | | | | noise do_each_thread/while_each_thread wrap a block of code that is in this format: for (...) do ... while If curly braces do not surround the inner loop the following warning is generated by sparse: warning: do-while statement is not a compound statement Fix the warning by adding the braces. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* generic-ipi: cleanup for generic_smp_call_function_interrupt()Xiao Guangrong2009-12-151-2/+1
| | | | | | | | | | | | | | | | Use smp_processor_id() instead of get_cpu() and put_cpu() in generic_smp_call_function_interrupt(), It's no need to disable preempt, because we must call generic_smp_call_function_interrupt() with interrupts disabled. Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'sysctl_max_map_count' should be non-negativeAmerigo Wang2009-12-151-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | Jan Engelhardt reported we have this problem: setting max_map_count to a value large enough results in programs dying at first try. This is on 2.6.31.6: 15:59 borg:/proc/sys/vm # echo $[1<<31-1] >max_map_count 15:59 borg:/proc/sys/vm # cat max_map_count 1073741824 15:59 borg:/proc/sys/vm # echo $[1<<31] >max_map_count 15:59 borg:/proc/sys/vm # cat max_map_count Killed This is because we have a chance to make 'max_map_count' negative. but it's meaningless. Make it only accept non-negative values. Reported-by: Jan Engelhardt <jengelh@medozas.de> Signed-off-by: WANG Cong <amwang@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: James Morris <jmorris@namei.org> Cc: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* hugetlb: derive huge pages nodes allowed from task mempolicyLee Schermerhorn2009-12-151-2/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch derives a "nodes_allowed" node mask from the numa mempolicy of the task modifying the number of persistent huge pages to control the allocation, freeing and adjusting of surplus huge pages when the pool page count is modified via the new sysctl or sysfs attribute "nr_hugepages_mempolicy". The nodes_allowed mask is derived as follows: * For "default" [NULL] task mempolicy, a NULL nodemask_t pointer is produced. This will cause the hugetlb subsystem to use node_online_map as the "nodes_allowed". This preserves the behavior before this patch. * For "preferred" mempolicy, including explicit local allocation, a nodemask with the single preferred node will be produced. "local" policy will NOT track any internode migrations of the task adjusting nr_hugepages. * For "bind" and "interleave" policy, the mempolicy's nodemask will be used. * Other than to inform the construction of the nodes_allowed node mask, the actual mempolicy mode is ignored. That is, all modes behave like interleave over the resulting nodes_allowed mask with no "fallback". See the updated documentation [next patch] for more information about the implications of this patch. Examples: Starting with: Node 0 HugePages_Total: 0 Node 1 HugePages_Total: 0 Node 2 HugePages_Total: 0 Node 3 HugePages_Total: 0 Default behavior [with or without this patch] balances persistent hugepage allocation across nodes [with sufficient contiguous memory]: sysctl vm.nr_hugepages[_mempolicy]=32 yields: Node 0 HugePages_Total: 8 Node 1 HugePages_Total: 8 Node 2 HugePages_Total: 8 Node 3 HugePages_Total: 8 Of course, we only have nr_hugepages_mempolicy with the patch, but with default mempolicy, nr_hugepages_mempolicy behaves the same as nr_hugepages. Applying mempolicy--e.g., with numactl [using '-m' a.k.a. '--membind' because it allows multiple nodes to be specified and it's easy to type]--we can allocate huge pages on individual nodes or sets of nodes. So, starting from the condition above, with 8 huge pages per node, add 8 more to node 2 using: numactl -m 2 sysctl vm.nr_hugepages_mempolicy=40 This yields: Node 0 HugePages_Total: 8 Node 1 HugePages_Total: 8 Node 2 HugePages_Total: 16 Node 3 HugePages_Total: 8 The incremental 8 huge pages were restricted to node 2 by the specified mempolicy. Similarly, we can use mempolicy to free persistent huge pages from specified nodes: numactl -m 0,1 sysctl vm.nr_hugepages_mempolicy=32 yields: Node 0 HugePages_Total: 4 Node 1 HugePages_Total: 4 Node 2 HugePages_Total: 16 Node 3 HugePages_Total: 8 The 8 huge pages freed were balanced over nodes 0 and 1. [rientjes@google.com: accomodate reworked NODEMASK_ALLOC] Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com> Acked-by: Mel Gorman <mel@csn.ul.ie> Reviewed-by: Andi Kleen <andi@firstfloor.org> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Randy Dunlap <randy.dunlap@oracle.com> Cc: Nishanth Aravamudan <nacc@us.ibm.com> Cc: Adam Litke <agl@us.ibm.com> Cc: Andy Whitcroft <apw@canonical.com> Cc: Eric Whitney <eric.whitney@hp.com> Cc: Christoph Lameter <cl@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* bsdacct: fix uid/gid misreportingAlexey Dobriyan2009-12-151-1/+2
| | | | | | | | | | | | | | | | | | | | commit d8e180dcd5bbbab9cd3ff2e779efcf70692ef541 "bsdacct: switch credentials for writing to the accounting file" introduced credential switching during final acct data collecting. However, uid/gid pair continued to be collected from current which became credentials of who created acct file, not who exits. Addresses http://bugzilla.kernel.org/show_bug.cgi?id=14676 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Reported-by: Juho K. Juopperi <jkj@kapsi.fi> Acked-by: Serge Hallyn <serue@us.ibm.com> Acked-by: David Howells <dhowells@redhat.com> Reviewed-by: Michal Schmidt <mschmidt@redhat.com> Cc: James Morris <jmorris@namei.org> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'for-linus' of ↵Linus Torvalds2009-12-1411-231/+84
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (34 commits) m68k: rename global variable vmalloc_end to m68k_vmalloc_end percpu: add missing per_cpu_ptr_to_phys() definition for UP percpu: Fix kdump failure if booted with percpu_alloc=page percpu: make misc percpu symbols unique percpu: make percpu symbols in ia64 unique percpu: make percpu symbols in powerpc unique percpu: make percpu symbols in x86 unique percpu: make percpu symbols in xen unique percpu: make percpu symbols in cpufreq unique percpu: make percpu symbols in oprofile unique percpu: make percpu symbols in tracer unique percpu: make percpu symbols under kernel/ and mm/ unique percpu: remove some sparse warnings percpu: make alloc_percpu() handle array types vmalloc: fix use of non-existent percpu variable in put_cpu_var() this_cpu: Use this_cpu_xx in trace_functions_graph.c this_cpu: Use this_cpu_xx for ftrace this_cpu: Use this_cpu_xx in nmi handling this_cpu: Use this_cpu operations in RCU this_cpu: Use this_cpu ops for VM statistics ... Fix up trivial (famous last words) global per-cpu naming conflicts in arch/x86/kvm/svm.c mm/slab.c
| * Merge branch 'for-linus' into for-nextTejun Heo2009-12-081-11/+11
| |\ | | | | | | | | | | | | Conflicts: mm/percpu.c
| * | percpu: make percpu symbols in tracer uniqueTejun Heo2009-10-292-27/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch updates percpu related symbols in kernel tracer such that percpu symbols are unique and don't clash with local symbols. This serves two purposes of decreasing the possibility of global percpu symbol collision and allowing dropping per_cpu__ prefix from percpu symbols. * kernel/trace/trace.c: s/max_data/max_tr_data/ * kernel/trace/trace_hw_branches: s/tracer/hwb_tracer/, s/buffer/hwb_buffer/ Partly based on Rusty Russell's "alloc_percpu: rename percpu vars which cause name clashes" patch. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com>
| * | percpu: make percpu symbols under kernel/ and mm/ uniqueTejun Heo2009-10-295-43/+45
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch updates percpu related symbols under kernel/ and mm/ such that percpu symbols are unique and don't clash with local symbols. This serves two purposes of decreasing the possibility of global percpu symbol collision and allowing dropping per_cpu__ prefix from percpu symbols. * kernel/lockdep.c: s/lock_stats/cpu_lock_stats/ * kernel/sched.c: s/init_rq_rt/init_rt_rq_var/ (any better idea?) s/sched_group_cpus/sched_groups/ * kernel/softirq.c: s/ksoftirqd/run_ksoftirqd/a * kernel/softlockup.c: s/(*)_timestamp/softlockup_\1_ts/ s/watchdog_task/softlockup_watchdog/ s/timestamp/ts/ for local variables * kernel/time/timer_stats: s/lookup_lock/tstats_lookup_lock/ * mm/slab.c: s/reap_work/slab_reap_work/ s/reap_node/slab_reap_node/ * mm/vmstat.c: local variable changed to avoid collision with vmstat_work Partly based on Rusty Russell's "alloc_percpu: rename percpu vars which cause name clashes" patch. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: (slab/vmstat) Christoph Lameter <cl@linux-foundation.org> Reviewed-by: Christoph Lameter <cl@linux-foundation.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Nick Piggin <npiggin@suse.de>
| * | this_cpu: Use this_cpu_xx in trace_functions_graph.cTejun Heo2009-10-131-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ftrace_cpu_disabled usage in trace_functions_graph.c were left out during this_cpu_xx conversion in commit 9288f99a causing compile failure. Convert them. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Christoph Lameter <cl@linux-foundation.org>
| * | this_cpu: Use this_cpu_xx for ftraceChristoph Lameter2009-10-122-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | this_cpu_xx can reduce the instruction count here and also avoid address arithmetic. Signed-off-by: Christoph Lameter <cl@linux-foundation.org> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Tejun Heo <tj@kernel.org>
| * | this_cpu: Use this_cpu operations in RCUChristoph Lameter2009-10-031-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | RCU does not do dynamic allocations but it increments per cpu variables a lot. These instructions results in a move to a register and then back to memory. This patch will make it use the inc/dec instructions on x86 that do not need a register. Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Christoph Lameter <cl@linux-foundation.org> Signed-off-by: Tejun Heo <tj@kernel.org>
| * | percpu: kill legacy percpu allocatorTejun Heo2009-10-021-150/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With ia64 converted, there's no arch left which still uses legacy percpu allocator. Kill it. Signed-off-by: Tejun Heo <tj@kernel.org> Delightedly-acked-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Ingo Molnar <mingo@redhat.com> Cc: Christoph Lameter <cl@linux-foundation.org>
* | | Merge branch 'sched-fixes-for-linus' of ↵Linus Torvalds2009-12-129-205/+256
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (21 commits) sched: Remove forced2_migrations stats sched: Fix memory leak in two error corner cases sched: Fix build warning in get_update_sysctl_factor() sched: Update normalized values on user updates via proc sched: Make tunable scaling style configurable sched: Fix missing sched tunable recalculation on cpu add/remove sched: Fix task priority bug sched: cgroup: Implement different treatment for idle shares sched: Remove unnecessary RCU exclusion sched: Discard some old bits sched: Clean up check_preempt_wakeup() sched: Move update_curr() in check_preempt_wakeup() to avoid redundant call sched: Sanitize fork() handling sched: Clean up ttwu() rq locking sched: Remove rq->clock coupling from set_task_cpu() sched: Consolidate select_task_rq() callers sched: Remove sysctl.sched_features sched: Protect sched_rr_get_param() access to task->sched_class sched: Protect task->cpus_allowed access in sched_getaffinity() sched: Fix balance vs hotplug race ... Fixed up conflicts in kernel/sysctl.c (due to sysctl cleanup)
| * | | sched: Remove forced2_migrations statsIngo Molnar2009-12-102-8/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This build warning: kernel/sched.c: In function 'set_task_cpu': kernel/sched.c:2070: warning: unused variable 'old_rq' Made me realize that the forced2_migrations stat looks pretty pointless (and a misnomer) - remove it. Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | sched: Fix memory leak in two error corner casesPhil Carmody2009-12-101-2/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If the second in each of these pairs of allocations fails, then the first one will not be freed in the error route out. Found by a static code analysis tool. Signed-off-by: Phil Carmody <ext-phil.2.carmody@nokia.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <1260448177-28448-1-git-send-email-ext-phil.2.carmody@nokia.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | sched: Fix build warning in get_update_sysctl_factor()Mike Galbraith2009-12-101-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Mike Galbraith <efault@gmx.de> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu> LKML-Reference: <new-submission>
| * | | sched: Update normalized values on user updates via procChristian Ehrhardt2009-12-093-8/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The normalized values are also recalculated in case the scaling factor changes. This patch updates the internally used scheduler tuning values that are normalized to one cpu in case a user sets new values via sysfs. Together with patch 2 of this series this allows to let user configured values scale (or not) to cpu add/remove events taking place later. Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <1259579808-11357-4-git-send-email-ehrhardt@linux.vnet.ibm.com> [ v2: fix warning ] Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | sched: Make tunable scaling style configurableChristian Ehrhardt2009-12-094-1/+51
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As scaling now takes place on all kind of cpu add/remove events a user that configures values via proc should be able to configure if his set values are still rescaled or kept whatever happens. As the comments state that log2 was just a second guess that worked the interface is not just designed for on/off, but to choose a scaling type. Currently this allows none, log and linear, but more important it allwos us to keep the interface even if someone has an even better idea how to scale the values. Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <1259579808-11357-3-git-send-email-ehrhardt@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | sched: Fix missing sched tunable recalculation on cpu add/removeChristian Ehrhardt2009-12-092-13/+32
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Based on Peter Zijlstras patch suggestion this enables recalculation of the scheduler tunables in response of a change in the number of cpus. It also adds a max of eight cpus that are considered in that scaling. Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <1259579808-11357-2-git-send-email-ehrhardt@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | sched: Fix task priority bugPeter Zijlstra2009-12-091-6/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 83f9ac removed a call to effective_prio() in wake_up_new_task(), which leads to tasks running at MAX_PRIO. This is caused by the idle thread being set to MAX_PRIO before forking off init. O(1) used that to make sure idle was always preempted, CFS uses check_preempt_curr_idle() for that so we can savely remove this bit of legacy code. Reported-by: Mike Galbraith <efault@gmx.de> Tested-by: Mike Galbraith <efault@gmx.de> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <1259754383.4003.610.camel@laptop> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | sched: cgroup: Implement different treatment for idle sharesPeter Zijlstra2009-12-091-2/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When setting the weight for a per-cpu task-group, we have to put in a phantom weight when there is no work on that cpu, otherwise we'll not service that cpu when new work gets placed there until we again update the per-cpu weights. We used to add these phantom weights to the total, so that the idle per-cpu shares don't get inflated, this however causes the non-idle parts to get deflated, causing unexpected weight distibutions. Reverse this, so that the non-idle shares are correct but the idle shares are inflated. Reported-by: Yasunori Goto <y-goto@jp.fujitsu.com> Tested-by: Yasunori Goto <y-goto@jp.fujitsu.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <1257934048.23203.76.camel@twins> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | sched: Remove unnecessary RCU exclusionPeter Zijlstra2009-12-091-7/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As Nick pointed out, and realized by myself when doing: sched: Fix balance vs hotplug race the patch: sched: for_each_domain() vs RCU is wrong, sched_domains are freed after synchronize_sched(), which means disabling preemption is enough. Reported-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | sched: Discard some old bitsPeter Zijlstra2009-12-094-19/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | WAKEUP_RUNNING was an experiment, not sure why that ever ended up being merged... Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | sched: Clean up check_preempt_wakeup()Peter Zijlstra2009-12-091-40/+33
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Streamline the wakeup preemption code a bit, unifying the preempt path so that they all do the same. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | sched: Move update_curr() in check_preempt_wakeup() to avoid redundant callJupyung Lee2009-12-091-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If a RT task is woken up while a non-RT task is running, check_preempt_wakeup() is called to check whether the new task can preempt the old task. The function returns quickly without going deeper because it is apparent that a RT task can always preempt a non-RT task. In this situation, check_preempt_wakeup() always calls update_curr() to update vruntime value of the currently running task. However, the function call is unnecessary and redundant at that moment because (1) a non-RT task can always be preempted by a RT task regardless of its vruntime value, and (2) update_curr() will be called shortly when the context switch between two occurs. By moving update_curr() in check_preempt_wakeup(), we can avoid redundant call to update_curr(), slightly reducing the time taken to wake up RT tasks. Signed-off-by: Jupyung Lee <jupyung@gmail.com> [ Place update_curr() right before the wake_preempt_entity() call, which is the only thing that relies on the updated vruntime ] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <1258451500-6714-1-git-send-email-jupyung@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | sched: Sanitize fork() handlingPeter Zijlstra2009-12-092-42/+33
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently we try to do task placement in wake_up_new_task() after we do the load-balance pass in sched_fork(). This yields complicated semantics in that we have to deal with tasks on different RQs and the set_task_cpu() calls in copy_process() and sched_fork() Rename ->task_new() to ->task_fork() and call it from sched_fork() before the balancing, this gives the policy a clear point to place the task. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | sched: Clean up ttwu() rq lockingPeter Zijlstra2009-12-091-8/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since set_task_clock() doesn't rely on rq->clock anymore we can simplyfy the mess in ttwu(). Optimize things a bit by not fiddling with the IRQ state there. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | sched: Remove rq->clock coupling from set_task_cpu()Peter Zijlstra2009-12-091-12/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | set_task_cpu() should be rq invariant and only touch task state, it currently fails to do so, which opens up a few races, since not all callers hold both rq->locks. Remove the relyance on rq->clock, as any site calling set_task_cpu() should also do a remote clock update, which should ensure the observed time between these two cpus is monotonic, as per kernel/sched_clock.c:sched_clock_remote(). Therefore we can simply remove the clock_offset bits and be happy. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | sched: Consolidate select_task_rq() callersPeter Zijlstra2009-12-091-3/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Small cleanup. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <new-submission> [ v2: build fix ] Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | sched: Remove sysctl.sched_featuresPeter Zijlstra2009-12-091-8/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since we've had a much saner debugfs interface to this, remove the sysctl one. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <new-submission> [ v2: build fix ] Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | sched: Protect sched_rr_get_param() access to task->sched_classThomas Gleixner2009-12-094-8/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | sched_rr_get_param calls task->sched_class->get_rr_interval(task) without protection against a concurrent sched_setscheduler() call which modifies task->sched_class. Serialize the access with task_rq_lock(task) and hand the rq pointer into get_rr_interval() as it's needed at least in the sched_fair implementation. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> LKML-Reference: <alpine.LFD.2.00.0912090930120.3089@localhost.localdomain> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | sched: Protect task->cpus_allowed access in sched_getaffinity()Thomas Gleixner2009-12-091-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | sched_getaffinity() is not protected against a concurrent modification of the tasks affinity. Serialize the access with task_rq_lock(task). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> LKML-Reference: <20091208202026.769251187@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | sched: Fix balance vs hotplug racePeter Zijlstra2009-12-063-27/+39
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since (e761b77: cpu hotplug, sched: Introduce cpu_active_map and redo sched domain managment) we have cpu_active_mask which is suppose to rule scheduler migration and load-balancing, except it never (fully) did. The particular problem being solved here is a crash in try_to_wake_up() where select_task_rq() ends up selecting an offline cpu because select_task_rq_fair() trusts the sched_domain tree to reflect the current state of affairs, similarly select_task_rq_rt() trusts the root_domain. However, the sched_domains are updated from CPU_DEAD, which is after the cpu is taken offline and after stop_machine is done. Therefore it can race perfectly well with code assuming the domains are right. Cure this by building the domains from cpu_active_mask on CPU_DOWN_PREPARE. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | cpumask: Fix generate_sched_domains() for UPGeert Uytterhoeven2009-12-061-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit acc3f5d7cabbfd6cec71f0c1f9900621fa2d6ae7 ("cpumask: Partition_sched_domains takes array of cpumask_var_t") changed the function signature of generate_sched_domains() for the CONFIG_SMP=y case, but forgot to update the corresponding function for the CONFIG_SMP=n case, causing: kernel/cpuset.c:2073: warning: passing argument 1 of 'generate_sched_domains' from incompatible pointer type Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <alpine.DEB.2.00.0912062038070.5693@ayla.of.borg> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | | | Merge branch 'timers-fixes-for-linus' of ↵Linus Torvalds2009-12-112-45/+81
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: itimer: Fix the itimer trace print format hrtimer: move timer stats helper functions to hrtimer.c hrtimer: Tune hrtimer_interrupt hang logic
| * | | | hrtimer: move timer stats helper functions to hrtimer.cHeiko Carstens2009-12-101-4/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is no reason to make timer_stats_hrtimer_set_start_info and friends visible to the rest of the kernel. So move all of them to hrtimer.c. Also make timer_stats_hrtimer_set_start_info a static inline function so it gets inlined and we avoid another function call. Based on a patch by Thomas Gleixner. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> LKML-Reference: <20091210095629.GC4144@osiris.boeblingen.de.ibm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | hrtimer: Tune hrtimer_interrupt hang logicThomas Gleixner2009-12-102-41/+61
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The hrtimer_interrupt hang logic adjusts min_delta_ns based on the execution time of the hrtimer callbacks. This is error-prone for virtual machines, where a guest vcpu can be scheduled out during the execution of the callbacks (and the callbacks themselves can do operations that translate to blocking operations in the hypervisor), which in can lead to large min_delta_ns rendering the system unusable. Replace the current heuristics with something more reliable. Allow the interrupt code to try 3 times to catch up with the lost time. If that fails use the total time spent in the interrupt handler to defer the next timer interrupt so the system can catch up with other things which got delayed. Limit that deferment to 100ms. The retry events and the maximum time spent in the interrupt handler are recorded and exposed via /proc/timer_list Inspired by a patch from Marcelo. Reported-by: Michael Tokarev <mjt@tls.msk.ru> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Marcelo Tosatti <mtosatti@redhat.com> Cc: kvm@vger.kernel.org
* | | | | Merge branch 'core-fixes-for-linus' of ↵Linus Torvalds2009-12-112-6/+20
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: lockdep: Avoid out of bounds array reference in save_trace() futex: Take mmap_sem for get_user_pages in fault_in_user_writeable lockstat: Add usage info to Documentation/lockstat.txt lockstat: Fix min, max times in /proc/lock_stats
| * | | | | lockdep: Avoid out of bounds array reference in save_trace()Luck, Tony2009-12-101-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ia64 found this the hard way (because we currently have a stub for save_stack_trace() that does nothing). But it would be a good idea to be cautious in case a real save_stack_trace() bailed out with an error before it set trace->nr_entries. Signed-off-by: Tony Luck <tony.luck@intel.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: luming.yu@intel.com LKML-Reference: <4b2024d085302c2a2@agluck-desktop.sc.intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | | futex: Take mmap_sem for get_user_pages in fault_in_user_writeableAndi Kleen2009-12-081-2/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | get_user_pages() must be called with mmap_sem held. Signed-off-by: Andi Kleen <ak@linux.intel.com> Cc: stable@kernel.org Cc: Andrew Morton <akpm@linuxfoundation.org> Cc: Nick Piggin <npiggin@suse.de> Cc: Darren Hart <dvhltc@us.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> LKML-Reference: <20091208121942.GA21298@basil.fritz.box> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | | | lockstat: Fix min, max times in /proc/lock_statsFrank Rowand2009-12-061-3/+10
| | |/ / / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix min, max times in /proc/lock_stats (1) When collecting lock hold and wait times, if the current minimum time is zero, it will be replaced by the next time. (2) When aggregating minimum and maximum lock hold and wait times accross cpus, the values are added, instead of selecting the minimum and maximum. Signed-off-by: Frank Rowand <frank.rowand@am.sony.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <4B05BBAE.2050005@am.sony.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | | | | Merge branch 'tracing-fixes-for-linus' of ↵Linus Torvalds2009-12-114-57/+242
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: tracing: Remove comparing of NULL to va_list in trace_array_vprintk() tracing: Fix function graph trace_pipe to properly display failed entries tracing: Add full state to trace_seq tracing: Buffer the output of seq_file in case of filled buffer tracing: Only call pipe_close if pipe_close is defined tracing: Add pipe_close interface
| * \ \ \ \ Merge branch 'tip/tracing/core3' of ↵Ingo Molnar2009-12-104-57/+242
| |\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace into tracing/core
| | * | | | | tracing: Remove comparing of NULL to va_list in trace_array_vprintk()Carsten Emde2009-12-091-6/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Olof Johansson stated the following: Comparing a va_list with NULL is bogus. It's supposed to be treated like an opaque type and only be manipulated with va_* accessors. Olof noticed that this code broke the ARM builds: kernel/trace/trace.c: In function 'trace_array_vprintk': kernel/trace/trace.c:1364: error: invalid operands to binary == (have 'va_list' and 'void *') kernel/trace/trace.c: In function 'tracing_mark_write': kernel/trace/trace.c:3349: error: incompatible type for argument 3 of 'trace_vprintk' This patch partly reverts c13d2f7c3231e873f30db92b96c8caa48f100f33 and re-installs the original mark_printk() mechanism. Reported-by: Olof Johansson <olof@lixom.net> Signed-off-by: Carsten Emde <C.Emde@osadl.org> LKML-Reference: <4B1BAB74.104@osadl.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| | * | | | | tracing: Fix function graph trace_pipe to properly display failed entriesJiri Olsa2009-12-091-34/+131
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is a case where the graph tracer might get confused and omits displaying of a single record. This applies mostly with the trace_pipe since it is unlikely that the trace_seq buffer will overflow with the trace file. As the function_graph tracer goes through the trace entries keeping a pointer to the current record: current -> func1 ENTRY func2 ENTRY func2 RETURN func1 RETURN When an function ENTRY is encountered, it moves the pointer to the next entry to check if the function is a nested or leaf function. func1 ENTRY current -> func2 ENTRY func2 RETURN func1 RETURN If the rest of the writing of the function fills the trace_seq buffer, then the trace_pipe read will ignore this entry. The next read will Now start at the current location, but the first entry (func1) will be discarded. This patch keeps a copy of the current entry in the iterator private storage and will keep track of when the trace_seq buffer fills. When the trace_seq buffer fills, it will reuse the copy of the entry in the next iteration. [ This patch has been largely modified by Steven Rostedt in order to clean it up and simplify it. The original idea and concept was from Jirka and for that, this patch will go under his name to give him the credit he deserves. But because this was modify by Steven Rostedt anything wrong with the patch should be blamed on Steven. ] Signed-off-by: Jiri Olsa <jolsa@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <1259067458-27143-1-git-send-email-jolsa@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| | * | | | | tracing: Add full state to trace_seqJohannes Berg2009-12-091-11/+50
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The trace_seq buffer might fill up, and right now one needs to check the return value of each printf into the buffer to check for that. Instead, have the buffer keep track of whether it is full or not, and reject more input if it is full or would have overflowed with an input that wasn't added. Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| | * | | | | tracing: Buffer the output of seq_file in case of filled bufferSteven Rostedt2009-12-092-6/+43
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If the seq_read fills the buffer it will call s_start again on the next itertation with the same position. This causes a problem with the function_graph tracer because it consumes the iteration in order to determine leaf functions. What happens is that the iterator stores the entry, and the function graph plugin will look at the next entry. If that next entry is a return of the same function and task, then the function is a leaf and the function_graph plugin calls ring_buffer_read which moves the ring buffer iterator forward (the trace iterator still points to the function start entry). The copying of the trace_seq to the seq_file buffer will fail if the seq_file buffer is full. The seq_read will not show this entry. The next read by userspace will cause seq_read to again call s_start which will reuse the trace iterator entry (the function start entry). But the function return entry was already consumed. The function graph plugin will think that this entry is a nested function and not a leaf. To solve this, the trace code now checks the return status of the seq_printf (trace_print_seq). If the writing to the seq_file buffer fails, we set a flag in the iterator (leftover) and we do not reset the trace_seq buffer. On the next call to s_start, we check the leftover flag, and if it is set, we just reuse the trace_seq buffer and do not call into the plugin print functions. Before this patch: 2) | fput() { 2) | __fput() { 2) 0.550 us | inotify_inode_queue_event(); 2) | __fsnotify_parent() { 2) 0.540 us | inotify_dentry_parent_queue_event(); After the patch: 2) | fput() { 2) | __fput() { 2) 0.550 us | inotify_inode_queue_event(); 2) 0.548 us | __fsnotify_parent(); 2) 0.540 us | inotify_dentry_parent_queue_event(); [ Updated the patch to fix a missing return 0 from the trace_print_seq() stub when CONFIG_TRACING is disabled. Reported-by: Ingo Molnar <mingo@elte.hu> ] Reported-by: Jiri Olsa <jolsa@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| | * | | | | tracing: Only call pipe_close if pipe_close is definedSteven Rostedt2009-12-091-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This fixes a cut and paste error that had pipe_close get called if pipe_open was defined (not pipe_close). Reported-by: Kosaki Motohiro <kosaki.motohiro@jp.fujitsu.com> LKML-Reference: <20091209153204.F4CD.A69D9226@jp.fujitsu.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| | * | | | | tracing: Add pipe_close interfaceSteven Rostedt2009-12-072-0/+6
| | |/ / / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | An ftrace plugin can add a pipe_open interface when the user opens trace_pipe. But if the plugin allocates something within the pipe_open it can not free it because there exists no pipe_close. The hook to the trace file open has a corresponding close. The closing of the trace_pipe file should also have a corresponding close. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
OpenPOWER on IntegriCloud