From: Greg KH <gregkh@suse.de>
To: linux-kernel@vger.kernel.org, stable@kernel.org
Cc: stable-review@kernel.org, torvalds@linux-foundation.org,
akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk,
Peter Zijlstra <a.p.zijlstra@chello.nl>,
Ingo Molnar <mingo@elte.hu>
Subject: [29/30] sched: Fix task priority bug
Date: Wed, 20 Jan 2010 20:15:50 -0800 [thread overview]
Message-ID: <20100121041836.286147376@mini.kroah.org> (raw)
In-Reply-To: <20100121041852.GA9656@kroah.com>
2.6.32-stable review patch. If anyone has any objections, please let us know.
------------------
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
commit 57785df5ac53c70da9fb53696130f3c551bfe1f9 upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---
kernel/sched.c | 6 ------
1 file changed, 6 deletions(-)
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -3177,10 +3177,6 @@ static void pull_task(struct rq *src_rq,
deactivate_task(src_rq, p, 0);
set_task_cpu(p, this_cpu);
activate_task(this_rq, p, 0);
- /*
- * Note that idle threads have a prio of MAX_PRIO, for this test
- * to be always true for them.
- */
check_preempt_curr(this_rq, p, 0);
}
@@ -6982,7 +6978,6 @@ void __cpuinit init_idle(struct task_str
__sched_fork(idle);
idle->se.exec_start = sched_clock();
- idle->prio = idle->normal_prio = MAX_PRIO;
cpumask_copy(&idle->cpus_allowed, cpumask_of(cpu));
__set_task_cpu(idle, cpu);
@@ -7686,7 +7681,6 @@ migration_call(struct notifier_block *nf
spin_lock_irq(&rq->lock);
update_rq_clock(rq);
deactivate_task(rq, rq->idle, 0);
- rq->idle->static_prio = MAX_PRIO;
__setscheduler(rq, rq->idle, SCHED_NORMAL, 0);
rq->idle->sched_class = &idle_sched_class;
migrate_dead_tasks(cpu);
next prev parent reply other threads:[~2010-01-21 4:24 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-01-21 4:18 [00/30] 2.6.32.5 review Greg KH
2010-01-21 4:15 ` [01/30] inotify: do not reuse watch descriptors Greg KH
2010-01-21 4:15 ` [02/30] inotify: only warn once for inotify problems Greg KH
2010-01-21 4:15 ` [03/30] revert "drivers/video/s3c-fb.c: fix clock setting for Samsung SoC Framebuffer" Greg KH
2010-01-21 4:15 ` [04/30] memcg: ensure list is empty at rmdir Greg KH
2010-01-21 4:15 ` [05/30] drm/i915: remove loop in Ironlake interrupt handler Greg KH
2010-01-21 4:15 ` [06/30] block: Fix incorrect reporting of partition alignment Greg KH
2010-01-21 4:15 ` [07/30] x86, mce: Thermal monitoring depends on APIC being enabled Greg KH
2010-01-21 4:15 ` [08/30] futexes: Remove rw parameter from get_futex_key() Greg KH
2010-01-21 4:15 ` [09/30] page allocator: update NR_FREE_PAGES only when necessary Greg KH
2010-01-21 4:15 ` [10/30] x86, apic: use physical mode for IBM summit platforms Greg KH
2010-01-21 4:15 ` [11/30] edac: i5000_edac critical fix panic out of bounds Greg KH
2010-01-21 4:15 ` [12/30] x86: SGI UV: Fix mapping of MMIO registers Greg KH
2010-01-21 4:15 ` [13/30] mfd: WM835x GPIO direction register is not locked Greg KH
2010-01-21 4:15 ` [14/30] mfd: Correct WM835x ISINK ramp time defines Greg KH
2010-01-21 4:15 ` [15/30] ALSA: hda - Fix missing capture mixer for ALC861/660 codecs Greg KH
2010-01-21 4:15 ` [16/30] V4L/DVB (13868): gspca - sn9c20x: Fix test of unsigned Greg KH
2010-01-21 4:15 ` [17/30] reiserfs: truncate blocks not used by a write Greg KH
2010-01-21 4:15 ` [18/30] HID: add device IDs for new model of Apple Wireless Keyboard Greg KH
2010-01-21 4:15 ` [19/30] PCI/cardbus: Add a fixup hook and fix powerpc Greg KH
2010-01-21 4:15 ` [20/30] [SCSI] megaraid_sas: remove sysfs poll_mode_io world writeable permissions Greg KH
2010-01-21 4:15 ` [21/30] Input: pmouse - move Sentelic probe down the list Greg KH
2010-01-21 4:15 ` [22/30] asus-laptop: add Lenovo SL hotkey support Greg KH
2010-01-21 4:15 ` [23/30] sched: Fix cpu_clock() in NMIs, on !CONFIG_HAVE_UNSTABLE_SCHED_CLOCK Greg KH
2010-01-21 4:15 ` [24/30] sparc64: Fix NMI programming when perf events are active Greg KH
2010-01-21 4:15 ` [25/30] sparc64: Fix Niagara2 perf event handling Greg KH
2010-01-21 4:15 ` [26/30] i2c: Do not use device name after device_unregister Greg KH
2010-01-21 4:15 ` [27/30] i2c/pca: Dont use *_interruptible Greg KH
2010-01-21 4:15 ` [28/30] serial/8250_pnp: add a new Fujitsu Wacom Tablet PC device Greg KH
2010-01-21 4:15 ` Greg KH [this message]
2010-01-21 4:15 ` [30/30] vfs: Fix vmtruncate() regression Greg KH
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