#ifdef CONFIG_SCHED_AUTOGROUP

#include <linux/kref.h>
#include <linux/rwsem.h>

struct autogroup {
	/*
	 * reference doesn't mean how many thread attach to this
	 * autogroup now. It just stands for the number of task
	 * could use this autogroup.
	 */
	struct kref		kref;
	struct task_group	*tg;
	struct rw_semaphore	lock;
	unsigned long		id;
	int			nice;
};

extern void autogroup_init(struct task_struct *init_task);
extern void autogroup_free(struct task_group *tg);

static inline bool task_group_is_autogroup(struct task_group *tg)
{
	return !!tg->autogroup;
}

extern bool task_wants_autogroup(struct task_struct *p, struct task_group *tg);

static inline struct task_group *
autogroup_task_group(struct task_struct *p, struct task_group *tg)
{
	int enabled = READ_ONCE(sysctl_sched_autogroup_enabled);

	if (enabled && task_wants_autogroup(p, tg))
		return p->signal->autogroup->tg;

	return tg;
}

extern int autogroup_path(struct task_group *tg, char *buf, int buflen);

#else /* !CONFIG_SCHED_AUTOGROUP */

static inline void autogroup_init(struct task_struct *init_task) {  }
static inline void autogroup_free(struct task_group *tg) { }
static inline bool task_group_is_autogroup(struct task_group *tg)
{
	return 0;
}

static inline struct task_group *
autogroup_task_group(struct task_struct *p, struct task_group *tg)
{
	return tg;
}

#ifdef CONFIG_SCHED_DEBUG
static inline int autogroup_path(struct task_group *tg, char *buf, int buflen)
{
	return 0;
}
#endif

#endif /* CONFIG_SCHED_AUTOGROUP */
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<div class='path'>path: <a href='/cgit.cgi/linux/net-next.git/commit/?id=433e19cf33d34bb6751c874a9c00980552fe508c'>root</a>/<a href='/cgit.cgi/linux/net-next.git/commit/include?id=433e19cf33d34bb6751c874a9c00980552fe508c'>include</a>/<a href='/cgit.cgi/linux/net-next.git/commit/include/sound?id=433e19cf33d34bb6751c874a9c00980552fe508c'>sound</a>/<a href='/cgit.cgi/linux/net-next.git/commit/include/sound/gus.h?id=433e19cf33d34bb6751c874a9c00980552fe508c'>gus.h</a></div><div class='content'><div class='cgit-panel'><b>diff options</b><form method='get'><input type='hidden' name='id' value='433e19cf33d34bb6751c874a9c00980552fe508c'/><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>Dexuan Cui &lt;decui@microsoft.com&gt;</td><td class='right'>2017-01-28 11:46:02 -0700</td></tr>
<tr><th>committer</th><td>Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;</td><td class='right'>2017-01-31 10:59:48 +0100</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/include/sound/gus.h?id=433e19cf33d34bb6751c874a9c00980552fe508c'>433e19cf33d34bb6751c874a9c00980552fe508c</a> (<a href='/cgit.cgi/linux/net-next.git/patch/include/sound/gus.h?id=433e19cf33d34bb6751c874a9c00980552fe508c'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?id=433e19cf33d34bb6751c874a9c00980552fe508c'>ce6547ef2987fbb289fa28f03536328a42781651</a> /<a href='/cgit.cgi/linux/net-next.git/tree/include/sound/gus.h?id=433e19cf33d34bb6751c874a9c00980552fe508c'>include/sound/gus.h</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/include/sound/gus.h?id=191e885a2e130e639bb0c8ee350d7047294f2ce6'>191e885a2e130e639bb0c8ee350d7047294f2ce6</a> (<a href='/cgit.cgi/linux/net-next.git/diff/include/sound/gus.h?id=433e19cf33d34bb6751c874a9c00980552fe508c&amp;id2=191e885a2e130e639bb0c8ee350d7047294f2ce6'>diff</a>)</td></tr></table>
<div class='commit-subject'>Drivers: hv: vmbus: finally fix hv_need_to_signal_on_read()</div><div class='commit-msg'>Commit a389fcfd2cb5 ("Drivers: hv: vmbus: Fix signaling logic in
hv_need_to_signal_on_read()")
added the proper mb(), but removed the test "prev_write_sz &lt; pending_sz"
when making the signal decision.

As a result, the guest can signal the host unnecessarily,
and then the host can throttle the guest because the host
thinks the guest is buggy or malicious; finally the user
running stress test can perceive intermittent freeze of
the guest.

This patch brings back the test, and properly handles the
in-place consumption APIs used by NetVSC (see get_next_pkt_raw(),
put_pkt_raw() and commit_rd_index()).

Fixes: a389fcfd2cb5 ("Drivers: hv: vmbus: Fix signaling logic in
hv_need_to_signal_on_read()")

Signed-off-by: Dexuan Cui &lt;decui@microsoft.com&gt;
Reported-by: Rolf Neugebauer &lt;rolf.neugebauer@docker.com&gt;
Tested-by: Rolf Neugebauer &lt;rolf.neugebauer@docker.com&gt;
Cc: "K. Y. Srinivasan" &lt;kys@microsoft.com&gt;
Cc: Haiyang Zhang &lt;haiyangz@microsoft.com&gt;
Cc: Stephen Hemminger &lt;sthemmin@microsoft.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: K. Y. Srinivasan &lt;kys@microsoft.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?id=433e19cf33d34bb6751c874a9c00980552fe508c'>Diffstat</a> (limited to 'include/sound/gus.h')</div><table summary='diffstat' class='diffstat'>