freebsd-dev/cddl/usr.sbin/zfsd/callout.cc
Alan Somers 7a0c41d5d7 zfsd(8), the ZFS fault management daemon
Add zfsd, which deals with hard drive faults in ZFS pools. It manages
hotspares and replements in drive slots that publish physical paths.

cddl/usr.sbin/zfsd
	Add zfsd(8) and its unit tests

cddl/usr.sbin/Makefile
	Add zfsd to the build

lib/libdevdctl
	A C++ library that helps devd clients process events

lib/Makefile
share/mk/bsd.libnames.mk
share/mk/src.libnames.mk
	Add libdevdctl to the build. It's a private library, unusable by
	out-of-tree software.

etc/defaults/rc.conf
	By default, set zfsd_enable to NO

etc/mtree/BSD.include.dist
	Add a directory for libdevdctl's include files

etc/mtree/BSD.tests.dist
	Add a directory for zfsd's unit tests

etc/mtree/BSD.var.dist
	Add /var/db/zfsd/cases, where zfsd stores case files while it's shut
	down.

etc/rc.d/Makefile
etc/rc.d/zfsd
	Add zfsd's rc script

sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev.c
	Fix the resource.fs.zfs.statechange message. It had a number of
	problems:

	It was only being emitted on a transition to the HEALTHY state.
	That made it impossible for zfsd to take actions based on drives
	getting sicker.

	It compared the new state to vdev_prevstate, which is the state that
	the vdev had the last time it was opened.  That doesn't make sense,
	because a vdev can change state multiple times without being
	reopened.

	vdev_set_state contains logic that will change the device's new
	state based on various conditions.  However, the statechange event
	was being posted _before_ that logic took effect.  Now it's being
	posted after.

Submitted by:	gibbs, asomers, mav, allanjude
Reviewed by:	mav, delphij
Relnotes:	yes
Sponsored by:	Spectra Logic Corp, iX Systems
Differential Revision:	https://reviews.freebsd.org/D6564
2016-05-28 17:43:40 +00:00

220 lines
5.5 KiB
C++

/*-
* Copyright (c) 2011, 2012, 2013 Spectra Logic Corporation
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions, and the following disclaimer,
* without modification.
* 2. Redistributions in binary form must reproduce at minimum a disclaimer
* substantially similar to the "NO WARRANTY" disclaimer below
* ("Disclaimer") and any redistribution must be conditioned upon
* including a substantially similar Disclaimer requirement for further
* binary redistribution.
*
* NO WARRANTY
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGES.
*
* Authors: Justin T. Gibbs (Spectra Logic Corporation)
*
* $FreeBSD$
*/
/**
* \file callout.cc
*
* \brief Implementation of the Callout class - multi-client
* timer services built on top of the POSIX interval timer.
*/
#include <sys/time.h>
#include <signal.h>
#include <syslog.h>
#include <climits>
#include <list>
#include <map>
#include <string>
#include <devdctl/guid.h>
#include <devdctl/event.h>
#include <devdctl/event_factory.h>
#include <devdctl/consumer.h>
#include <devdctl/exception.h>
#include "callout.h"
#include "vdev_iterator.h"
#include "zfsd.h"
#include "zfsd_exception.h"
std::list<Callout *> Callout::s_activeCallouts;
bool Callout::s_alarmFired(false);
void
Callout::Init()
{
signal(SIGALRM, Callout::AlarmSignalHandler);
}
bool
Callout::Stop()
{
if (!IsPending())
return (false);
for (std::list<Callout *>::iterator it(s_activeCallouts.begin());
it != s_activeCallouts.end(); it++) {
if (*it != this)
continue;
it = s_activeCallouts.erase(it);
if (it != s_activeCallouts.end()) {
/*
* Maintain correct interval for the
* callouts that follow the just removed
* entry.
*/
timeradd(&(*it)->m_interval, &m_interval,
&(*it)->m_interval);
}
break;
}
m_pending = false;
return (true);
}
bool
Callout::Reset(const timeval &interval, CalloutFunc_t *func, void *arg)
{
bool cancelled(false);
if (!timerisset(&interval))
throw ZfsdException("Callout::Reset: interval of 0");
cancelled = Stop();
m_interval = interval;
m_func = func;
m_arg = arg;
m_pending = true;
std::list<Callout *>::iterator it(s_activeCallouts.begin());
for (; it != s_activeCallouts.end(); it++) {
if (timercmp(&(*it)->m_interval, &m_interval, <=)) {
/*
* Decrease our interval by those that come
* before us.
*/
timersub(&m_interval, &(*it)->m_interval, &m_interval);
} else {
/*
* Account for the time between the newly
* inserted event and those that follow.
*/
timersub(&(*it)->m_interval, &m_interval,
&(*it)->m_interval);
break;
}
}
s_activeCallouts.insert(it, this);
if (s_activeCallouts.front() == this) {
itimerval timerval = { {0, 0}, m_interval };
setitimer(ITIMER_REAL, &timerval, NULL);
}
return (cancelled);
}
void
Callout::AlarmSignalHandler(int)
{
s_alarmFired = true;
ZfsDaemon::WakeEventLoop();
}
void
Callout::ExpireCallouts()
{
if (!s_alarmFired)
return;
s_alarmFired = false;
if (s_activeCallouts.empty()) {
/* Callout removal/SIGALRM race was lost. */
return;
}
/*
* Expire the first callout (the one we used to set the
* interval timer) as well as any callouts following that
* expire at the same time (have a zero interval from
* the callout before it).
*/
do {
Callout *cur(s_activeCallouts.front());
s_activeCallouts.pop_front();
cur->m_pending = false;
cur->m_func(cur->m_arg);
} while (!s_activeCallouts.empty()
&& timerisset(&s_activeCallouts.front()->m_interval) == 0);
if (!s_activeCallouts.empty()) {
Callout *next(s_activeCallouts.front());
itimerval timerval = { { 0, 0 }, next->m_interval };
setitimer(ITIMER_REAL, &timerval, NULL);
}
}
timeval
Callout::TimeRemaining() const
{
/*
* Outline: Add the m_interval for each callout in s_activeCallouts
* ahead of this, except for the first callout. Add to that the result
* of getitimer (That's because the first callout stores its original
* interval setting while the timer is ticking).
*/
itimerval timervalToAlarm;
timeval timeToExpiry;
std::list<Callout *>::iterator it;
if (!IsPending()) {
timeToExpiry.tv_sec = INT_MAX;
timeToExpiry.tv_usec = 999999; /*maximum normalized value*/
return (timeToExpiry);
}
timerclear(&timeToExpiry);
getitimer(ITIMER_REAL, &timervalToAlarm);
timeval& timeToAlarm = timervalToAlarm.it_value;
timeradd(&timeToExpiry, &timeToAlarm, &timeToExpiry);
it =s_activeCallouts.begin();
it++; /*skip the first callout in the list*/
for (; it != s_activeCallouts.end(); it++) {
timeradd(&timeToExpiry, &(*it)->m_interval, &timeToExpiry);
if ((*it) == this)
break;
}
return (timeToExpiry);
}