.TH CPUPOWER\-SET "1" "22/02/2011" "" "cpupower Manual"
.SH NAME
cpupower\-set \- Set processor power related kernel or hardware configurations
.SH SYNOPSIS
.ft B
.B cpupower set [ \-b VAL ]


.SH DESCRIPTION
\fBcpupower set \fP sets kernel configurations or directly accesses hardware
registers affecting processor power saving policies.

Some options are platform wide, some affect single cores. By default values
are applied on all cores. How to modify single core configurations is
described in the cpupower(1) manpage in the \-\-cpu option section. Whether an
option affects the whole system or can be applied to individual cores is
described in the Options sections.

Use \fBcpupower info \fP to read out current settings and whether they are
supported on the system at all.

.SH Options
.PP
\-\-perf-bias, \-b
.RS 4
Sets a register on supported Intel processore which allows software to convey
its policy for the relative importance of performance versus energy savings to
the  processor.

The range of valid numbers is 0-15, where 0 is maximum
performance and 15 is maximum energy efficiency.

The processor uses this information in model-specific ways
when it must select trade-offs between performance and
energy efficiency.

This policy hint does not supersede Processor Performance states
(P-states) or CPU Idle power states (C-states), but allows
software to have influence where it would otherwise be unable
to express a preference.

For example, this setting may tell the hardware how
aggressively or conservatively to control frequency
in the "turbo range" above the explicitly OS-controlled
P-state frequency range.  It may also tell the hardware
how aggressively it should enter the OS requested C-states.

This option can be applied to individual cores only via the \-\-cpu option,
cpupower(1).

Setting the performance bias value on one CPU can modify the setting on
related CPUs as well (for example all CPUs on one socket), because of
hardware restrictions.
Use \fBcpupower -c all info -b\fP to verify.

This options needs the msr kernel driver (CONFIG_X86_MSR) loaded.
.RE

.SH "SEE ALSO"
cpupower-info(1), cpupower-monitor(1), powertop(1)
.PP
.SH AUTHORS
.nf
\-\-perf\-bias parts written by Len Brown <len.brown@intel.com>
Thomas Renninger <trenn@suse.de>
ogy.c'>
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<input type='submit' value='search'/>
</form>
</td></tr></table>
<div class='path'>path: <a href='/cgit.cgi/linux/net-next.git/commit/?id=92c715fca907686f5298220ece53423e38ba3aed'>root</a>/<a href='/cgit.cgi/linux/net-next.git/commit/tools?id=92c715fca907686f5298220ece53423e38ba3aed'>tools</a>/<a href='/cgit.cgi/linux/net-next.git/commit/tools/perf?id=92c715fca907686f5298220ece53423e38ba3aed'>perf</a>/<a href='/cgit.cgi/linux/net-next.git/commit/tools/perf/tests?id=92c715fca907686f5298220ece53423e38ba3aed'>tests</a>/<a href='/cgit.cgi/linux/net-next.git/commit/tools/perf/tests/topology.c?id=92c715fca907686f5298220ece53423e38ba3aed'>topology.c</a></div><div class='content'><div class='cgit-panel'><b>diff options</b><form method='get'><input type='hidden' name='id' value='92c715fca907686f5298220ece53423e38ba3aed'/><table><tr><td colspan='2'/></tr><tr><td class='label'>context:</td><td class='ctrl'><select name='context' onchange='this.form.submit();'><option value='1'>1</option><option value='2'>2</option><option value='3' selected='selected'>3</option><option value='4'>4</option><option value='5'>5</option><option value='6'>6</option><option value='7'>7</option><option value='8'>8</option><option value='9'>9</option><option value='10'>10</option><option value='15'>15</option><option value='20'>20</option><option value='25'>25</option><option value='30'>30</option><option value='35'>35</option><option value='40'>40</option></select></td></tr><tr><td class='label'>space:</td><td class='ctrl'><select name='ignorews' onchange='this.form.submit();'><option value='0' selected='selected'>include</option><option value='1'>ignore</option></select></td></tr><tr><td class='label'>mode:</td><td class='ctrl'><select name='dt' onchange='this.form.submit();'><option value='0' selected='selected'>unified</option><option value='1'>ssdiff</option><option value='2'>stat only</option></select></td></tr><tr><td/><td class='ctrl'><noscript><input type='submit' value='reload'/></noscript></td></tr></table></form></div><table summary='commit info' class='commit-info'>
<tr><th>author</th><td>Maarten Lankhorst &lt;maarten.lankhorst@linux.intel.com&gt;</td><td class='right'>2017-01-31 10:25:25 +0100</td></tr>
<tr><th>committer</th><td>Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;</td><td class='right'>2017-01-31 13:41:46 +0100</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/tools/perf/tests/topology.c?id=92c715fca907686f5298220ece53423e38ba3aed'>92c715fca907686f5298220ece53423e38ba3aed</a> (<a href='/cgit.cgi/linux/net-next.git/patch/tools/perf/tests/topology.c?id=92c715fca907686f5298220ece53423e38ba3aed'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?id=92c715fca907686f5298220ece53423e38ba3aed'>286158fdad04c9b54955350abb95d4f1c0dc860a</a> /<a href='/cgit.cgi/linux/net-next.git/tree/tools/perf/tests/topology.c?id=92c715fca907686f5298220ece53423e38ba3aed'>tools/perf/tests/topology.c</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/tools/perf/tests/topology.c?id=e6e7b48b295afa5a5ab440de0a94d9ad8b3ce2d0'>e6e7b48b295afa5a5ab440de0a94d9ad8b3ce2d0</a> (<a href='/cgit.cgi/linux/net-next.git/diff/tools/perf/tests/topology.c?id=92c715fca907686f5298220ece53423e38ba3aed&amp;id2=e6e7b48b295afa5a5ab440de0a94d9ad8b3ce2d0'>diff</a>)</td></tr></table>
<div class='commit-subject'>drm/atomic: Fix double free in drm_atomic_state_default_clear</div><div class='commit-msg'>drm_atomic_helper_page_flip and drm_atomic_ioctl set their own events
in crtc_state-&gt;event. But when it's set the event is freed in 2 places.

Solve this by only freeing the event in the atomic ioctl when it
allocated its own event.

This has been broken twice. The first time when the code was introduced,
but only in the corner case when an event is allocated, but more crtc's
were included by atomic check and then failing. This can mostly
happen when you do an atomic modeset in i915 and the display clock is
changed, which forces all crtc's to be included to the state.

This has been broken worse by adding in-fences support, which caused
the double free to be done unconditionally.

[IGT] kms_rotation_crc: starting subtest primary-rotation-180
=============================================================================
BUG kmalloc-128 (Tainted: G     U         ): Object already free
-----------------------------------------------------------------------------

Disabling lock debugging due to kernel taint
INFO: Allocated in drm_atomic_helper_setup_commit+0x285/0x2f0 [drm_kms_helper] age=0 cpu=3 pid=1529
 ___slab_alloc+0x308/0x3b0
 __slab_alloc+0xd/0x20
 kmem_cache_alloc_trace+0x92/0x1c0
 drm_atomic_helper_setup_commit+0x285/0x2f0 [drm_kms_helper]
 intel_atomic_commit+0x35/0x4f0 [i915]
 drm_atomic_commit+0x46/0x50 [drm]
 drm_mode_atomic_ioctl+0x7d4/0xab0 [drm]
 drm_ioctl+0x2b3/0x490 [drm]
 do_vfs_ioctl+0x69c/0x700
 SyS_ioctl+0x4e/0x80
 entry_SYSCALL_64_fastpath+0x13/0x94
INFO: Freed in drm_event_cancel_free+0xa3/0xb0 [drm] age=0 cpu=3 pid=1529
 __slab_free+0x48/0x2e0
 kfree+0x159/0x1a0
 drm_event_cancel_free+0xa3/0xb0 [drm]
 drm_mode_atomic_ioctl+0x86d/0xab0 [drm]
 drm_ioctl+0x2b3/0x490 [drm]
 do_vfs_ioctl+0x69c/0x700
 SyS_ioctl+0x4e/0x80
 entry_SYSCALL_64_fastpath+0x13/0x94
INFO: Slab 0xffffde1f0997b080 objects=17 used=2 fp=0xffff92fb65ec2578 flags=0x200000000008101
INFO: Object 0xffff92fb65ec2578 @offset=1400 fp=0xffff92fb65ec2ae8

Redzone ffff92fb65ec2570: bb bb bb bb bb bb bb bb                          ........
Object ffff92fb65ec2578: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkkkkkkkkkkkkk
Object ffff92fb65ec2588: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkkkkkkkkkkkkk
Object ffff92fb65ec2598: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkkkkkkkkkkkkk
Object ffff92fb65ec25a8: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkkkkkkkkkkkkk
Object ffff92fb65ec25b8: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkkkkkkkkkkkkk
Object ffff92fb65ec25c8: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkkkkkkkkkkkkk
Object ffff92fb65ec25d8: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkkkkkkkkkkkkk
Object ffff92fb65ec25e8: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b a5  kkkkkkkkkkkkkkk.
Redzone ffff92fb65ec25f8: bb bb bb bb bb bb bb bb                          ........
Padding ffff92fb65ec2738: 5a 5a 5a 5a 5a 5a 5a 5a                          ZZZZZZZZ
CPU: 3 PID: 180 Comm: kworker/3:2 Tainted: G    BU          4.10.0-rc6-patser+ #5039
Hardware name:                  /NUC5PPYB, BIOS PYBSWCEL.86A.0031.2015.0601.1712 06/01/2015
Workqueue: events intel_atomic_helper_free_state [i915]
Call Trace:
 dump_stack+0x4d/0x6d
 print_trailer+0x20c/0x220
 free_debug_processing+0x1c6/0x330
 ? drm_atomic_state_default_clear+0xf7/0x1c0 [drm]
 __slab_free+0x48/0x2e0
 ? drm_atomic_state_default_clear+0xf7/0x1c0 [drm]
 kfree+0x159/0x1a0
 drm_atomic_state_default_clear+0xf7/0x1c0 [drm]
 ? drm_atomic_state_clear+0x30/0x30 [drm]
 intel_atomic_state_clear+0xd/0x20 [i915]
 drm_atomic_state_clear+0x1a/0x30 [drm]
 __drm_atomic_state_free+0x13/0x60 [drm]
 intel_atomic_helper_free_state+0x5d/0x70 [i915]
 process_one_work+0x260/0x4a0
 worker_thread+0x2d1/0x4f0
 kthread+0x127/0x130
 ? process_one_work+0x4a0/0x4a0
 ? kthread_stop+0x120/0x120
 ret_from_fork+0x29/0x40
FIX kmalloc-128: Object at 0xffff92fb65ec2578 not freed

Fixes: 3b24f7d67581 ("drm/atomic: Add struct drm_crtc_commit to track async updates")
Fixes: 9626014258a5 ("drm/fence: add in-fences support")
Cc: &lt;stable@vger.kernel.org&gt; # v4.8+
Cc: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Signed-off-by: Maarten Lankhorst &lt;maarten.lankhorst@linux.intel.com&gt;
Reviewed-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Reviewed-by: Gustavo Padovan &lt;gustavo.padovan@collabora.com&gt;
Signed-off-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Link: http://patchwork.freedesktop.org/patch/msgid/1485854725-27640-1-git-send-email-maarten.lankhorst@linux.intel.com
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?id=92c715fca907686f5298220ece53423e38ba3aed'>Diffstat</a> (limited to 'tools/perf/tests/topology.c')</div><table summary='diffstat' class='diffstat'>