/*
 * Regression3
 * Description:
 * Helper radix_tree_iter_retry resets next_index to the current index.
 * In following radix_tree_next_slot current chunk size becomes zero.
 * This isn't checked and it tries to dereference null pointer in slot.
 *
 * Helper radix_tree_iter_resume reset slot to NULL and next_index to index + 1,
 * for tagger iteraction it also must reset cached tags in iterator to abort
 * next radix_tree_next_slot and go to slow-path into radix_tree_next_chunk.
 *
 * Running:
 * This test should run to completion immediately. The above bug would
 * cause it to segfault.
 *
 * Upstream commit:
 * Not yet
 */
#include <linux/kernel.h>
#include <linux/gfp.h>
#include <linux/slab.h>
#include <linux/radix-tree.h>
#include <stdlib.h>
#include <stdio.h>

#include "regression.h"

void regression3_test(void)
{
	RADIX_TREE(root, GFP_KERNEL);
	void *ptr0 = (void *)4ul;
	void *ptr = (void *)8ul;
	struct radix_tree_iter iter;
	void **slot;
	bool first;

	printf("running regression test 3 (should take milliseconds)\n");

	radix_tree_insert(&root, 0, ptr0);
	radix_tree_tag_set(&root, 0, 0);

	first = true;
	radix_tree_for_each_tagged(slot, &root, &iter, 0, 0) {
		printf("tagged %ld %p\n", iter.index, *slot);
		if (first) {
			radix_tree_insert(&root, 1, ptr);
			radix_tree_tag_set(&root, 1, 0);
			first = false;
		}
		if (radix_tree_deref_retry(*slot)) {
			printf("retry at %ld\n", iter.index);
			slot = radix_tree_iter_retry(&iter);
			continue;
		}
	}
	radix_tree_delete(&root, 1);

	first = true;
	radix_tree_for_each_slot(slot, &root, &iter, 0) {
		printf("slot %ld %p\n", iter.index, *slot);
		if (first) {
			radix_tree_insert(&root, 1, ptr);
			first = false;
		}
		if (radix_tree_deref_retry(*slot)) {
			printk("retry at %ld\n", iter.index);
			slot = radix_tree_iter_retry(&iter);
			continue;
		}
	}
	radix_tree_delete(&root, 1);

	first = true;
	radix_tree_for_each_contig(slot, &root, &iter, 0) {
		printk("contig %ld %p\n", iter.index, *slot);
		if (first) {
			radix_tree_insert(&root, 1, ptr);
			first = false;
		}
		if (radix_tree_deref_retry(*slot)) {
			printk("retry at %ld\n", iter.index);
			slot = radix_tree_iter_retry(&iter);
			continue;
		}
	}

	radix_tree_for_each_slot(slot, &root, &iter, 0) {
		printf("slot %ld %p\n", iter.index, *slot);
		if (!iter.index) {
			printf("next at %ld\n", iter.index);
			slot = radix_tree_iter_resume(slot, &iter);
		}
	}

	radix_tree_for_each_contig(slot, &root, &iter, 0) {
		printf("contig %ld %p\n", iter.index, *slot);
		if (!iter.index) {
			printf("next at %ld\n", iter.index);
			slot = radix_tree_iter_resume(slot, &iter);
		}
	}

	radix_tree_tag_set(&root, 0, 0);
	radix_tree_tag_set(&root, 1, 0);
	radix_tree_for_each_tagged(slot, &root, &iter, 0, 0) {
		printf("tagged %ld %p\n", iter.index, *slot);
		if (!iter.index) {
			printf("next at %ld\n", iter.index);
			slot = radix_tree_iter_resume(slot, &iter);
		}
	}

	radix_tree_delete(&root, 0);
	radix_tree_delete(&root, 1);

	printf("regression test 3 passed\n");
}
21e4a1f31f98194e4f6b6cae7'>root</a>/<a href='/cgit.cgi/linux/net-next.git/commit/kernel?h=nds-private-remove&amp;id=79c6f448c8b79c321e4a1f31f98194e4f6b6cae7'>kernel</a>/<a href='/cgit.cgi/linux/net-next.git/commit/kernel/events?h=nds-private-remove&amp;id=79c6f448c8b79c321e4a1f31f98194e4f6b6cae7'>events</a>/<a href='/cgit.cgi/linux/net-next.git/commit/kernel/events/hw_breakpoint.c?h=nds-private-remove&amp;id=79c6f448c8b79c321e4a1f31f98194e4f6b6cae7'>hw_breakpoint.c</a></div><div class='content'><div class='cgit-panel'><b>diff options</b><form method='get'><input type='hidden' name='h' value='nds-private-remove'/><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/kernel/events/hw_breakpoint.c?h=nds-private-remove&amp;id=79c6f448c8b79c321e4a1f31f98194e4f6b6cae7'>79c6f448c8b79c321e4a1f31f98194e4f6b6cae7</a> (<a href='/cgit.cgi/linux/net-next.git/patch/kernel/events/hw_breakpoint.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/?h=nds-private-remove&amp;id=79c6f448c8b79c321e4a1f31f98194e4f6b6cae7'>370efda701f03cccf21e02bb1fdd3b852547d75c</a> /<a href='/cgit.cgi/linux/net-next.git/tree/kernel/events/hw_breakpoint.c?h=nds-private-remove&amp;id=79c6f448c8b79c321e4a1f31f98194e4f6b6cae7'>kernel/events/hw_breakpoint.c</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/kernel/events/hw_breakpoint.c?h=nds-private-remove&amp;id=0c744ea4f77d72b3dcebb7a8f2684633ec79be88'>0c744ea4f77d72b3dcebb7a8f2684633ec79be88</a> (<a href='/cgit.cgi/linux/net-next.git/diff/kernel/events/hw_breakpoint.c?h=nds-private-remove&amp;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/?h=nds-private-remove&amp;id=79c6f448c8b79c321e4a1f31f98194e4f6b6cae7'>Diffstat</a> (limited to 'kernel/events/hw_breakpoint.c')</div><table summary='diffstat' class='diffstat'>