/*
 * netsniff-ng - the packet sniffing beast
 * Copyright 2009, 2010 Daniel Borkmann.
 * Copyright 2010 Emmanuel Roullit.
 * Subject to the GPL, version 2.
 */

#include <stdio.h>
#include <stdint.h>
#include <netinet/in.h>    /* for ntohs() */

#include "proto.h"
#include "protos.h"
#include "dissector_eth.h"
#include "pkt_buff.h"

struct vlanhdr {
	uint16_t h_vlan_TCI;
	uint16_t h_vlan_encapsulated_proto;
} __attribute__((packed));

static void vlan(struct pkt_buff *pkt)
{
	uint16_t tci;
	struct vlanhdr *vlan = (struct vlanhdr *) pkt_pull(pkt, sizeof(*vlan));

	if (vlan == NULL)
		return;

	tci = ntohs(vlan->h_vlan_TCI);

	tprintf(" [ VLAN ");
	tprintf("Prio (%d), ", (tci & 0xE000) >> 13);
	tprintf("CFI (%d), ", (tci & 0x1000) >> 12);
	tprintf("ID (%d), ", (tci & 0x0FFF));
	tprintf("Proto (0x%.4x)", ntohs(vlan->h_vlan_encapsulated_proto));
	tprintf(" ]\n");

	pkt_set_proto(pkt, &eth_lay2, ntohs(vlan->h_vlan_encapsulated_proto));
}

static void vlan_less(struct pkt_buff *pkt)
{
	uint16_t tci;
	struct vlanhdr *vlan = (struct vlanhdr *) pkt_pull(pkt, sizeof(*vlan));

	if (vlan == NULL)
		return;

	tci = ntohs(vlan->h_vlan_TCI);

	tprintf(" VLAN%d", (tci & 0x0FFF));

	pkt_set_proto(pkt, &eth_lay2, ntohs(vlan->h_vlan_encapsulated_proto));
}

struct protocol vlan_ops = {
	.key = 0x8100,
	.print_full = vlan,
	.print_less = vlan_less,
};
ubmit' value='switch'/></form></td></tr>
<tr><td class='sub'>net-next plumbings</td><td class='sub right'>Tobias Klauser</td></tr></table>
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<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='229ce631574761870a2ac938845fadbd07f35caa'/><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>Wanpeng Li &lt;wanpeng.li@hotmail.com&gt;</td><td class='right'>2016-07-14 16:15:56 +0800</td></tr>
<tr><th>committer</th><td>Ingo Molnar &lt;mingo@kernel.org&gt;</td><td class='right'>2016-08-10 14:13:28 +0200</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/?h=nds-private-remove&amp;id=229ce631574761870a2ac938845fadbd07f35caa'>229ce631574761870a2ac938845fadbd07f35caa</a> (<a href='/cgit.cgi/linux/net-next.git/patch/?id=229ce631574761870a2ac938845fadbd07f35caa'>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=229ce631574761870a2ac938845fadbd07f35caa'>ef5627be2364a5105a5a9fd7dd4d2fac942e8594</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/?h=nds-private-remove&amp;id=2db34e8bf9a22f4e38b29deccee57457bc0e7d74'>2db34e8bf9a22f4e38b29deccee57457bc0e7d74</a> (<a href='/cgit.cgi/linux/net-next.git/diff/?h=nds-private-remove&amp;id=229ce631574761870a2ac938845fadbd07f35caa&amp;id2=2db34e8bf9a22f4e38b29deccee57457bc0e7d74'>diff</a>)</td></tr></table>
<div class='commit-subject'>locking/pvqspinlock: Fix double hash race</div><div class='commit-msg'>When the lock holder vCPU is racing with the queue head:

   CPU 0 (lock holder)    CPU1 (queue head)
   ===================    =================
   spin_lock();           spin_lock();
    pv_kick_node():        pv_wait_head_or_lock():
                            if (!lp) {
                             lp = pv_hash(lock, pn);
                             xchg(&amp;l-&gt;locked, _Q_SLOW_VAL);
                            }
                            WRITE_ONCE(pn-&gt;state, vcpu_halted);
     cmpxchg(&amp;pn-&gt;state,
      vcpu_halted, vcpu_hashed);
     WRITE_ONCE(l-&gt;locked, _Q_SLOW_VAL);
     (void)pv_hash(lock, pn);

In this case, lock holder inserts the pv_node of queue head into the
hash table and set _Q_SLOW_VAL unnecessary. This patch avoids it by
restoring/setting vcpu_hashed state after failing adaptive locking
spinning.

Signed-off-by: Wanpeng Li &lt;wanpeng.li@hotmail.com&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Reviewed-by: Pan Xinhui &lt;xinhui.pan@linux.vnet.ibm.com&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Davidlohr Bueso &lt;dave@stgolabs.net&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Paul E. McKenney &lt;paulmck@linux.vnet.ibm.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Waiman Long &lt;Waiman.Long@hpe.com&gt;
Link: http://lkml.kernel.org/r/1468484156-4521-1-git-send-email-wanpeng.li@hotmail.com
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?h=nds-private-remove&amp;id=229ce631574761870a2ac938845fadbd07f35caa'>Diffstat</a></div><table summary='diffstat' class='diffstat'>