perf-mem(1)
===========

NAME
----
perf-mem - Profile memory accesses

SYNOPSIS
--------
[verse]
'perf mem' [<options>] (record [<command>] | report)

DESCRIPTION
-----------
"perf mem record" runs a command and gathers memory operation data
from it, into perf.data. Perf record options are accepted and are passed through.

"perf mem report" displays the result. It invokes perf report with the
right set of options to display a memory access profile. By default, loads
and stores are sampled. Use the -t option to limit to loads or stores.

Note that on Intel systems the memory latency reported is the use-latency,
not the pure load (or store latency). Use latency includes any pipeline
queueing delays in addition to the memory subsystem latency.

OPTIONS
-------
<command>...::
	Any command you can specify in a shell.

-t::
--type=::
	Select the memory operation type: load or store (default: load,store)

-D::
--dump-raw-samples=::
	Dump the raw decoded samples on the screen in a format that is easy to parse with
	one sample per line.

-x::
--field-separator::
	Specify the field separator used when dump raw samples (-D option). By default,
	The separator is the space character.

-C::
--cpu-list::
	Restrict dump of raw samples to those provided via this option. Note that the same
	option can be passed in record mode. It will be interpreted the same way as perf
	record.

-K::
--all-kernel::
	Configure all used events to run in kernel space.

-U::
--all-user::
	Configure all used events to run in user space.

--ldload::
	Specify desired latency for loads event.

SEE ALSO
--------
linkperf:perf-record[1], linkperf:perf-report[1]
git.cgi/linux/net-next.git/log/net/sched/cls_u32.c'>log</a><a href='/cgit.cgi/linux/net-next.git/tree/net/sched/cls_u32.c?id=79c6f448c8b79c321e4a1f31f98194e4f6b6cae7'>tree</a><a class='active' href='/cgit.cgi/linux/net-next.git/commit/net/sched/cls_u32.c?id=79c6f448c8b79c321e4a1f31f98194e4f6b6cae7'>commit</a><a href='/cgit.cgi/linux/net-next.git/diff/net/sched/cls_u32.c?id=79c6f448c8b79c321e4a1f31f98194e4f6b6cae7'>diff</a></td><td class='form'><form class='right' method='get' action='/cgit.cgi/linux/net-next.git/log/net/sched/cls_u32.c'>
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<div class='path'>path: <a href='/cgit.cgi/linux/net-next.git/commit/?id=79c6f448c8b79c321e4a1f31f98194e4f6b6cae7'>root</a>/<a href='/cgit.cgi/linux/net-next.git/commit/net?id=79c6f448c8b79c321e4a1f31f98194e4f6b6cae7'>net</a>/<a href='/cgit.cgi/linux/net-next.git/commit/net/sched?id=79c6f448c8b79c321e4a1f31f98194e4f6b6cae7'>sched</a>/<a href='/cgit.cgi/linux/net-next.git/commit/net/sched/cls_u32.c?id=79c6f448c8b79c321e4a1f31f98194e4f6b6cae7'>cls_u32.c</a></div><div class='content'><div class='cgit-panel'><b>diff options</b><form method='get'><input type='hidden' name='id' value='79c6f448c8b79c321e4a1f31f98194e4f6b6cae7'/><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>Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;</td><td class='right'>2017-01-30 19:27:10 -0500</td></tr>
<tr><th>committer</th><td>Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;</td><td class='right'>2017-01-31 09:13:49 -0500</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/net/sched/cls_u32.c?id=79c6f448c8b79c321e4a1f31f98194e4f6b6cae7'>79c6f448c8b79c321e4a1f31f98194e4f6b6cae7</a> (<a href='/cgit.cgi/linux/net-next.git/patch/net/sched/cls_u32.c?id=79c6f448c8b79c321e4a1f31f98194e4f6b6cae7'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?id=79c6f448c8b79c321e4a1f31f98194e4f6b6cae7'>370efda701f03cccf21e02bb1fdd3b852547d75c</a> /<a href='/cgit.cgi/linux/net-next.git/tree/net/sched/cls_u32.c?id=79c6f448c8b79c321e4a1f31f98194e4f6b6cae7'>net/sched/cls_u32.c</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/net/sched/cls_u32.c?id=0c744ea4f77d72b3dcebb7a8f2684633ec79be88'>0c744ea4f77d72b3dcebb7a8f2684633ec79be88</a> (<a href='/cgit.cgi/linux/net-next.git/diff/net/sched/cls_u32.c?id=79c6f448c8b79c321e4a1f31f98194e4f6b6cae7&amp;id2=0c744ea4f77d72b3dcebb7a8f2684633ec79be88'>diff</a>)</td></tr></table>
<div class='commit-subject'>tracing: Fix hwlat kthread migration</div><div class='commit-msg'>The hwlat tracer creates a kernel thread at start of the tracer. It is
pinned to a single CPU and will move to the next CPU after each period of
running. If the user modifies the migration thread's affinity, it will not
change after that happens.

The original code created the thread at the first instance it was called,
but later was changed to destroy the thread after the tracer was finished,
and would not be created until the next instance of the tracer was
established. The code that initialized the affinity was only called on the
initial instantiation of the tracer. After that, it was not initialized, and
the previous affinity did not match the current newly created one, making
it appear that the user modified the thread's affinity when it did not, and
the thread failed to migrate again.

Cc: stable@vger.kernel.org
Fixes: 0330f7aa8ee6 ("tracing: Have hwlat trace migrate across tracing_cpumask CPUs")
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?id=79c6f448c8b79c321e4a1f31f98194e4f6b6cae7'>Diffstat</a> (limited to 'net/sched/cls_u32.c')</div><table summary='diffstat' class='diffstat'>