linux/kernel/sched.c, branch v2.6.30

sched: account system time properly

2009-04-29T13:02:28Z

Andrew Gallatin reported that IRQ and SOFTIRQ times were sometime not reported correctly on recent kernels, and even bisected to commit 457533a7d3402d1d91fbc125c8bd1bd16dcd3cd4 ([PATCH] fix scaled & unscaled cputime accounting) as the first bad commit. Further analysis pointed that commit 79741dd35713ff4f6fd0eafd59fa94e8a4ba922d ([PATCH] idle cputime accounting) was the real cause of the problem. account_process_tick() was not taking into account timer IRQ interrupting the idle task servicing a hard or soft irq. On mostly idle cpu, irqs were thus not accounted and top or mpstat could tell user/admin that cpu was 100 % idle, 0.00 % irq, 0.00 % softirq, while it was not. [ Impact: fix occasionally incorrect CPU statistics in top/mpstat ] Reported-by: Andrew Gallatin Re-reported-by: Andrew Morton Signed-off-by: Eric Dumazet Acked-by: Martin Schwidefsky Cc: rick.jones2@hp.com Cc: brice@myri.com Cc: Paul Mackerras Cc: Benjamin Herrenschmidt LKML-Reference: <49F84BC1.7080602@cosmosbay.com> Signed-off-by: Ingo Molnar

sched: Avoid printing sched_group::__cpu_power for default case

2009-04-16T22:46:05Z

Commit 46e0bb9c12f4 ("sched: Print sched_group::__cpu_power in sched_domain_debug") produces a messy dmesg output while attempting to print the sched_group::__cpu_power for each group in the sched_domain hierarchy. Fix this by avoid printing the __cpu_power for default cases. (i.e, __cpu_power == SCHED_LOAD_SCALE). [ Impact: reduce syslog clutter ] Reported-by: Tony Luck Signed-off-by: Gautham R Shenoy Fixed-by: Tony Luck Cc: a.p.zijlstra@chello.nl LKML-Reference: <20090414033936.GA534@in.ibm.com> Signed-off-by: Ingo Molnar

tracing, sched: mark get_parent_ip() notrace

2009-04-14T00:11:05Z

Impact: remove overly redundant tracing entries When tracer is "function" or "function_graph", way too much "get_parent_ip" entries are recorded in ring_buffer. Signed-off-by: Lai Jiangshan Acked-by: Frederic Weisbecker Acked-by: Steven Rostedt LKML-Reference: <49D458B1.5000703@cn.fujitsu.com> Signed-off-by: Ingo Molnar

Merge commit 'v2.6.30-rc1' into sched/urgent

2009-04-08T15:26:00Z

Merge reason: update to latest upstream to queue up fix Signed-off-by: Ingo Molnar

Merge branch 'locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

2009-04-06T20:37:30Z

* 'locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: lockdep: add stack dumps to asserts hrtimer: fix rq->lock inversion (again)

Merge branch 'tracing-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

2009-04-05T18:04:19Z

* 'tracing-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (413 commits) tracing, net: fix net tree and tracing tree merge interaction tracing, powerpc: fix powerpc tree and tracing tree interaction ring-buffer: do not remove reader page from list on ring buffer free function-graph: allow unregistering twice trace: make argument 'mem' of trace_seq_putmem() const tracing: add missing 'extern' keywords to trace_output.h tracing: provide trace_seq_reserve() blktrace: print out BLK_TN_MESSAGE properly blktrace: extract duplidate code blktrace: fix memory leak when freeing struct blk_io_trace blktrace: fix blk_probes_ref chaos blktrace: make classic output more classic blktrace: fix off-by-one bug blktrace: fix the original blktrace blktrace: fix a race when creating blk_tree_root in debugfs blktrace: fix timestamp in binary output tracing, Text Edit Lock: cleanup tracing: filter fix for TRACE_EVENT_FORMAT events ftrace: Using FTRACE_WARN_ON() to check "freed record" in ftrace_release() x86: kretprobe-booster interrupt emulation code fix ... Fix up trivial conflicts in arch/parisc/include/asm/ftrace.h include/linux/memory.h kernel/extable.c kernel/module.c

Merge git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-cpumask

2009-04-05T17:33:07Z

* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-cpumask: (36 commits) cpumask: remove cpumask allocation from idle_balance, fix numa, cpumask: move numa_node_id default implementation to topology.h, fix cpumask: remove cpumask allocation from idle_balance x86: cpumask: x86 mmio-mod.c use cpumask_var_t for downed_cpus x86: cpumask: update 32-bit APM not to mug current->cpus_allowed x86: microcode: cleanup x86: cpumask: use work_on_cpu in arch/x86/kernel/microcode_core.c cpumask: fix CONFIG_CPUMASK_OFFSTACK=y cpu hotunplug crash numa, cpumask: move numa_node_id default implementation to topology.h cpumask: convert node_to_cpumask_map[] to cpumask_var_t cpumask: remove x86 cpumask_t uses. cpumask: use cpumask_var_t in uv_flush_tlb_others. cpumask: remove cpumask_t assignment from vector_allocation_domain() cpumask: make Xen use the new operators. cpumask: clean up summit's send_IPI functions cpumask: use new cpumask functions throughout x86 x86: unify cpu_callin_mask/cpu_callout_mask/cpu_initialized_mask/cpu_sibling_setup_mask cpumask: convert struct cpuinfo_x86's llc_shared_map to cpumask_var_t cpumask: convert node_to_cpumask_map[] to cpumask_var_t x86: unify 32 and 64-bit node_to_cpumask_map ...

Merge branch 'ipi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

2009-04-04T00:33:30Z

* 'ipi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: s390: remove arch specific smp_send_stop() panic: clean up kernel/panic.c panic, smp: provide smp_send_stop() wrapper on UP too panic: decrease oops_in_progress only after having done the panic generic-ipi: eliminate WARN_ON()s during oops/panic generic-ipi: cleanups generic-ipi: remove CSD_FLAG_WAIT generic-ipi: remove kmalloc() generic IPI: simplify barriers and locking

Merge branch 'tracing/core-v2' into tracing-for-linus

2009-04-01T22:49:02Z

Conflicts: include/linux/slub_def.h lib/Kconfig.debug mm/slob.c mm/slub.c

epoll keyed wakeups: add __wake_up_locked_key() and __wake_up_sync_key()

2009-04-01T15:59:20Z

This patchset introduces wakeup hints for some of the most popular (from epoll POV) devices, so that epoll code can avoid spurious wakeups on its waiters. The problem with epoll is that the callback-based wakeups do not, ATM, carry any information about the events the wakeup is related to. So the only choice epoll has (not being able to call f_op->poll() from inside the callback), is to add the file* to a ready-list and resolve the real events later on, at epoll_wait() (or its own f_op->poll()) time. This can cause spurious wakeups, since the wake_up() itself might be for an event the caller is not interested into. The rate of these spurious wakeup can be pretty high in case of many network sockets being monitored. By allowing devices to report the events the wakeups refer to (at least the two major classes - POLLIN/POLLOUT), we are able to spare useless wakeups by proper handling inside the epoll's poll callback. Epoll will have in any case to call f_op->poll() on the file* later on, since the change to be done in order to have the full event set sent via wakeup, is too invasive for the way our f_op->poll() system works (the full event set is calculated inside the poll function - there are too many of them to even start thinking the change - also poll/select would need change too). Epoll is changed in a way that both devices which send event hints, and the ones that don't, are correctly handled. The former will gain some efficiency though. As a general rule for devices, would be to add an event mask by using key-aware wakeup macros, when making up poll wait queues. I tested it (together with the epoll's poll fix patch Andrew has in -mm) and wakeups for the supported devices are correctly filtered. Test program available here: http://www.xmailserver.org/epoll_test.c This patch: Nothing revolutionary here. Just using the available "key" that our wakeup core already support. The __wake_up_locked_key() was no brainer, since both __wake_up_locked() and __wake_up_locked_key() are thin wrappers around __wake_up_common(). The __wake_up_sync() function had a body, so the choice was between borrowing the body for __wake_up_sync_key() and calling it from __wake_up_sync(), or make an inline and calling it from both. I chose the former since in most archs it all resolves to "mov $0, REG; jmp ADDR". Signed-off-by: Davide Libenzi Cc: Alan Cox Cc: Ingo Molnar Cc: David Miller Cc: William Lee Irwin III Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds