---

yaml
---
r: 277487
b: refs/heads/master
c: 29e9bf1
h: refs/heads/master
i:
  277485: 9797889
  277483: c4abc44
  277479: a02bad0
  277471: 75925bd
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 82406da4a6998a0c98db0c5afb1695f97889bf79
+refs/heads/master: 29e9bf1841e4f9df13b4992a716fece7087dd237

trunk/Documentation/ABI/testing/sysfs-bus-rbd

@@ -57,6 +57,13 @@ create_snap
 
 	 $ echo <snap-name> > /sys/bus/rbd/devices/<dev-id>/snap_create
 
+rollback_snap
+
+	Rolls back data to the specified snapshot. This goes over the entire
+	list of rados blocks and sends a rollback command to each.
+
+	 $ echo <snap-name> > /sys/bus/rbd/devices/<dev-id>/snap_rollback
+
 snap_*
 
 	A directory per each snapshot

trunk/Documentation/DocBook/debugobjects.tmpl

@@ -96,7 +96,6 @@
 	<listitem><para>debug_object_deactivate</para></listitem>
 	<listitem><para>debug_object_destroy</para></listitem>
 	<listitem><para>debug_object_free</para></listitem>
-	<listitem><para>debug_object_assert_init</para></listitem>
       </itemizedlist>
       Each of these functions takes the address of the real object and
       a pointer to the object type specific debug description
@@ -274,26 +273,6 @@
 	debug checks.
       </para>
     </sect1>
-
-    <sect1 id="debug_object_assert_init">
-      <title>debug_object_assert_init</title>
-      <para>
-	This function is called to assert that an object has been
-	initialized.
-      </para>
-      <para>
-	When the real object is not tracked by debugobjects, it calls
-	fixup_assert_init of the object type description structure
-	provided by the caller, with the hardcoded object state
-	ODEBUG_NOT_AVAILABLE. The fixup function can correct the problem
-	by calling debug_object_init and other specific initializing
-	functions.
-      </para>
-      <para>
-	When the real object is already tracked by debugobjects it is
-	ignored.
-      </para>
-    </sect1>
   </chapter>
   <chapter id="fixupfunctions">
     <title>Fixup functions</title>
@@ -402,35 +381,6 @@
 	statistics.
       </para>
     </sect1>
-    <sect1 id="fixup_assert_init">
-      <title>fixup_assert_init</title>
-      <para>
-	This function is called from the debug code whenever a problem
-	in debug_object_assert_init is detected.
-      </para>
-      <para>
-	Called from debug_object_assert_init() with a hardcoded state
-	ODEBUG_STATE_NOTAVAILABLE when the object is not found in the
-	debug bucket.
-      </para>
-      <para>
-	The function returns 1 when the fixup was successful,
-	otherwise 0. The return value is used to update the
-	statistics.
-      </para>
-      <para>
-	Note, this function should make sure debug_object_init() is
-	called before returning.
-      </para>
-      <para>
-	The handling of statically initialized objects is a special
-	case. The fixup function should check if this is a legitimate
-	case of a statically initialized object or not. In this case only
-	debug_object_init() should be called to make the object known to
-	the tracker. Then the function should return 0 because this is not
-	a real fixup.
-      </para>
-    </sect1>
   </chapter>
   <chapter id="bugs">
     <title>Known Bugs And Assumptions</title>

trunk/Documentation/RCU/checklist.txt

@@ -328,12 +328,6 @@ over a rather long period of time, but improvements are always welcome!
 	RCU rather than SRCU, because RCU is almost always faster and
 	easier to use than is SRCU.
 
-	If you need to enter your read-side critical section in a
-	hardirq or exception handler, and then exit that same read-side
-	critical section in the task that was interrupted, then you need
-	to srcu_read_lock_raw() and srcu_read_unlock_raw(), which avoid
-	the lockdep checking that would otherwise this practice illegal.
-
 	Also unlike other forms of RCU, explicit initialization
 	and cleanup is required via init_srcu_struct() and
 	cleanup_srcu_struct().	These are passed a "struct srcu_struct"

trunk/Documentation/RCU/rcu.txt

@@ -38,11 +38,11 @@ o	How can the updater tell when a grace period has completed
 
 	Preemptible variants of RCU (CONFIG_TREE_PREEMPT_RCU) get the
 	same effect, but require that the readers manipulate CPU-local
-	counters.  These counters allow limited types of blocking within
-	RCU read-side critical sections.  SRCU also uses CPU-local
-	counters, and permits general blocking within RCU read-side
-	critical sections.  These variants of RCU detect grace periods
-	by sampling these counters.
+	counters.  These counters allow limited types of blocking
+	within RCU read-side critical sections.  SRCU also uses
+	CPU-local counters, and permits general blocking within
+	RCU read-side critical sections.  These two variants of
+	RCU detect grace periods by sampling these counters.
 
 o	If I am running on a uniprocessor kernel, which can only do one
 	thing at a time, why should I wait for a grace period?

trunk/Documentation/RCU/stallwarn.txt

@@ -101,11 +101,6 @@ o	A CPU-bound real-time task in a CONFIG_PREEMPT_RT kernel that
 	CONFIG_TREE_PREEMPT_RCU case, you might see stall-warning
 	messages.
 
-o	A hardware or software issue shuts off the scheduler-clock
-	interrupt on a CPU that is not in dyntick-idle mode.  This
-	problem really has happened, and seems to be most likely to
-	result in RCU CPU stall warnings for CONFIG_NO_HZ=n kernels.
-
 o	A bug in the RCU implementation.
 
 o	A hardware failure.  This is quite unlikely, but has occurred
@@ -114,11 +109,12 @@ o	A hardware failure.  This is quite unlikely, but has occurred
 	This resulted in a series of RCU CPU stall warnings, eventually
 	leading the realization that the CPU had failed.
 
-The RCU, RCU-sched, and RCU-bh implementations have CPU stall warning.
-SRCU does not have its own CPU stall warnings, but its calls to
-synchronize_sched() will result in RCU-sched detecting RCU-sched-related
-CPU stalls.  Please note that RCU only detects CPU stalls when there is
-a grace period in progress.  No grace period, no CPU stall warnings.
+The RCU, RCU-sched, and RCU-bh implementations have CPU stall
+warning.  SRCU does not have its own CPU stall warnings, but its
+calls to synchronize_sched() will result in RCU-sched detecting
+RCU-sched-related CPU stalls.  Please note that RCU only detects
+CPU stalls when there is a grace period in progress.  No grace period,
+no CPU stall warnings.
 
 To diagnose the cause of the stall, inspect the stack traces.
 The offending function will usually be near the top of the stack.

trunk/Documentation/RCU/torture.txt

@@ -61,24 +61,11 @@ nreaders	This is the number of RCU reading threads supported.
 		To properly exercise RCU implementations with preemptible
 		read-side critical sections.
 
-onoff_interval
-		The number of seconds between each attempt to execute a
-		randomly selected CPU-hotplug operation.  Defaults to
-		zero, which disables CPU hotplugging.  In HOTPLUG_CPU=n
-		kernels, rcutorture will silently refuse to do any
-		CPU-hotplug operations regardless of what value is
-		specified for onoff_interval.
-
 shuffle_interval
 		The number of seconds to keep the test threads affinitied
 		to a particular subset of the CPUs, defaults to 3 seconds.
 		Used in conjunction with test_no_idle_hz.
 
-shutdown_secs	The number of seconds to run the test before terminating
-		the test and powering off the system.  The default is
-		zero, which disables test termination and system shutdown.
-		This capability is useful for automated testing.
-
 stat_interval	The number of seconds between output of torture
 		statistics (via printk()).  Regardless of the interval,
 		statistics are printed when the module is unloaded.

trunk/Documentation/RCU/trace.txt

@@ -105,10 +105,14 @@ o	"dt" is the current value of the dyntick counter that is incremented
 	or one greater than the interrupt-nesting depth otherwise.
 	The number after the second "/" is the NMI nesting depth.
 
+	This field is displayed only for CONFIG_NO_HZ kernels.
+
 o	"df" is the number of times that some other CPU has forced a
 	quiescent state on behalf of this CPU due to this CPU being in
 	dynticks-idle state.
 
+	This field is displayed only for CONFIG_NO_HZ kernels.
+
 o	"of" is the number of times that some other CPU has forced a
 	quiescent state on behalf of this CPU due to this CPU being
 	offline.  In a perfect world, this might never happen, but it

trunk/Documentation/RCU/whatisRCU.txt

@@ -4,7 +4,6 @@ to start learning about RCU:
 1.	What is RCU, Fundamentally?  http://lwn.net/Articles/262464/
 2.	What is RCU? Part 2: Usage   http://lwn.net/Articles/263130/
 3.	RCU part 3: the RCU API      http://lwn.net/Articles/264090/
-4.	The RCU API, 2010 Edition    http://lwn.net/Articles/418853/
 
 
 What is RCU?
@@ -835,8 +834,6 @@ SRCU:	Critical sections	Grace period		Barrier
 
 	srcu_read_lock		synchronize_srcu	N/A
 	srcu_read_unlock	synchronize_srcu_expedited
-	srcu_read_lock_raw
-	srcu_read_unlock_raw
 	srcu_dereference
 
 SRCU:	Initialization/cleanup
@@ -858,33 +855,27 @@ list can be helpful:
 
 a.	Will readers need to block?  If so, you need SRCU.
 
-b.	Is it necessary to start a read-side critical section in a
-	hardirq handler or exception handler, and then to complete
-	this read-side critical section in the task that was
-	interrupted?  If so, you need SRCU's srcu_read_lock_raw() and
-	srcu_read_unlock_raw() primitives.
-
-c.	What about the -rt patchset?  If readers would need to block
+b.	What about the -rt patchset?  If readers would need to block
 	in an non-rt kernel, you need SRCU.  If readers would block
 	in a -rt kernel, but not in a non-rt kernel, SRCU is not
 	necessary.
 
-d.	Do you need to treat NMI handlers, hardirq handlers,
+c.	Do you need to treat NMI handlers, hardirq handlers,
 	and code segments with preemption disabled (whether
 	via preempt_disable(), local_irq_save(), local_bh_disable(),
 	or some other mechanism) as if they were explicit RCU readers?
 	If so, you need RCU-sched.
 
-e.	Do you need RCU grace periods to complete even in the face
+d.	Do you need RCU grace periods to complete even in the face
 	of softirq monopolization of one or more of the CPUs?  For
 	example, is your code subject to network-based denial-of-service
 	attacks?  If so, you need RCU-bh.
 
-f.	Is your workload too update-intensive for normal use of
+e.	Is your workload too update-intensive for normal use of
 	RCU, but inappropriate for other synchronization mechanisms?
 	If so, consider SLAB_DESTROY_BY_RCU.  But please be careful!
 
-g.	Otherwise, use RCU.
+f.	Otherwise, use RCU.
 
 Of course, this all assumes that you have determined that RCU is in fact
 the right tool for your job.

trunk/Documentation/atomic_ops.txt

@@ -84,93 +84,6 @@ compiler optimizes the section accessing atomic_t variables.
 
 *** YOU HAVE BEEN WARNED! ***
 
-Properly aligned pointers, longs, ints, and chars (and unsigned
-equivalents) may be atomically loaded from and stored to in the same
-sense as described for atomic_read() and atomic_set().  The ACCESS_ONCE()
-macro should be used to prevent the compiler from using optimizations
-that might otherwise optimize accesses out of existence on the one hand,
-or that might create unsolicited accesses on the other.
-
-For example consider the following code:
-
-	while (a > 0)
-		do_something();
-
-If the compiler can prove that do_something() does not store to the
-variable a, then the compiler is within its rights transforming this to
-the following:
-
-	tmp = a;
-	if (a > 0)
-		for (;;)
-			do_something();
-
-If you don't want the compiler to do this (and you probably don't), then
-you should use something like the following:
-
-	while (ACCESS_ONCE(a) < 0)
-		do_something();
-
-Alternatively, you could place a barrier() call in the loop.
-
-For another example, consider the following code:
-
-	tmp_a = a;
-	do_something_with(tmp_a);
-	do_something_else_with(tmp_a);
-
-If the compiler can prove that do_something_with() does not store to the
-variable a, then the compiler is within its rights to manufacture an
-additional load as follows:
-
-	tmp_a = a;
-	do_something_with(tmp_a);
-	tmp_a = a;
-	do_something_else_with(tmp_a);
-
-This could fatally confuse your code if it expected the same value
-to be passed to do_something_with() and do_something_else_with().
-
-The compiler would be likely to manufacture this additional load if
-do_something_with() was an inline function that made very heavy use
-of registers: reloading from variable a could save a flush to the
-stack and later reload.  To prevent the compiler from attacking your
-code in this manner, write the following:
-
-	tmp_a = ACCESS_ONCE(a);
-	do_something_with(tmp_a);
-	do_something_else_with(tmp_a);
-
-For a final example, consider the following code, assuming that the
-variable a is set at boot time before the second CPU is brought online
-and never changed later, so that memory barriers are not needed:
-
-	if (a)
-		b = 9;
-	else
-		b = 42;
-
-The compiler is within its rights to manufacture an additional store
-by transforming the above code into the following:
-
-	b = 42;
-	if (a)
-		b = 9;
-
-This could come as a fatal surprise to other code running concurrently
-that expected b to never have the value 42 if a was zero.  To prevent
-the compiler from doing this, write something like:
-
-	if (a)
-		ACCESS_ONCE(b) = 9;
-	else
-		ACCESS_ONCE(b) = 42;
-
-Don't even -think- about doing this without proper use of memory barriers,
-locks, or atomic operations if variable a can change at runtime!
-
-*** WARNING: ACCESS_ONCE() DOES NOT IMPLY A BARRIER! ***
-
 Now, we move onto the atomic operation interfaces typically implemented with
 the help of assembly code.
 

trunk/Documentation/kernel-parameters.txt

@@ -1885,11 +1885,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 			arch_perfmon: [X86] Force use of architectural
 				perfmon on Intel CPUs instead of the
 				CPU specific event set.
-			timer: [X86] Force use of architectural NMI
-				timer mode (see also oprofile.timer
-				for generic hr timer mode)
-				[s390] Force legacy basic mode sampling
-                                (report cpu_type "timer")
 
 	oops=panic	Always panic on oopses. Default is to just kill the
 			process, but there is a small probability of
@@ -2755,10 +2750,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 			functions are at fixed addresses, they make nice
 			targets for exploits that can control RIP.
 
-			emulate     [default] Vsyscalls turn into traps and are
-			            emulated reasonably safely.
+			emulate     Vsyscalls turn into traps and are emulated
+			            reasonably safely.
 
-			native      Vsyscalls are native syscall instructions.
+			native      [default] Vsyscalls are native syscall
+			            instructions.
 			            This is a little bit faster than trapping
 			            and makes a few dynamic recompilers work
 			            better than they would in emulation mode.