---

yaml
---
r: 30654
b: refs/heads/master
c: f6e6e88
h: refs/heads/master
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: f964c303fe33b0d2ee563349bc8bea4d57d7a265
+refs/heads/master: f6e6e883730aff2718610d3eba7608fcf73328ed

trunk/CREDITS

@@ -24,6 +24,11 @@ S: C. Negri 6, bl. D3
 S: Iasi 6600
 S: Romania
 
+N: Mark Adler
+E: madler@alumni.caltech.edu
+W: http://alumnus.caltech.edu/~madler/
+D: zlib decompression
+
 N: Monalisa Agrawal
 E: magrawal@nortelnetworks.com
 D: Basic Interphase 5575 driver with UBR and ABR support.
@@ -1573,12 +1578,8 @@ S: 160 00 Praha 6
 S: Czech Republic
 
 N: Niels Kristian Bech Jensen
-E: nkbj@image.dk
-W: http://www.image.dk/~nkbj
+E: nkbj1970@hotmail.com
 D: Miscellaneous kernel updates and fixes.
-S: Dr. Holsts Vej 34, lejl. 164
-S: DK-8230 �byh�j
-S: Denmark
 
 N: Michael K. Johnson
 E: johnsonm@redhat.com

trunk/Documentation/DocBook/kernel-api.tmpl

@@ -62,6 +62,8 @@
      <sect1><title>Internal Functions</title>
 !Ikernel/exit.c
 !Ikernel/signal.c
+!Iinclude/linux/kthread.h
+!Ekernel/kthread.c
      </sect1>
 
      <sect1><title>Kernel objects manipulation</title>
@@ -114,6 +116,29 @@ X!Ilib/string.c
      </sect1>
   </chapter>
 
+  <chapter id="kernel-lib">
+     <title>Basic Kernel Library Functions</title>
+
+     <para>
+       The Linux kernel provides more basic utility functions.
+     </para>
+
+     <sect1><title>Bitmap Operations</title>
+!Elib/bitmap.c
+!Ilib/bitmap.c
+     </sect1>
+
+     <sect1><title>Command-line Parsing</title>
+!Elib/cmdline.c
+     </sect1>
+
+     <sect1><title>CRC Functions</title>
+!Elib/crc16.c
+!Elib/crc32.c
+!Elib/crc-ccitt.c
+     </sect1>
+  </chapter>
+
   <chapter id="mm">
      <title>Memory Management in Linux</title>
      <sect1><title>The Slab Cache</title>
@@ -281,12 +306,13 @@ X!Ekernel/module.c
      <sect1><title>MTRR Handling</title>
 !Earch/i386/kernel/cpu/mtrr/main.c
      </sect1>
+
      <sect1><title>PCI Support Library</title>
 !Edrivers/pci/pci.c
 !Edrivers/pci/pci-driver.c
 !Edrivers/pci/remove.c
 !Edrivers/pci/pci-acpi.c
-<!-- kerneldoc does not understand to __devinit
+<!-- kerneldoc does not understand __devinit
 X!Edrivers/pci/search.c
  -->
 !Edrivers/pci/msi.c
@@ -315,6 +341,13 @@ X!Earch/i386/kernel/mca.c
      </sect1>
   </chapter>
 
+  <chapter id="firmware">
+     <title>Firmware Interfaces</title>
+     <sect1><title>DMI Interfaces</title>
+!Edrivers/firmware/dmi_scan.c
+     </sect1>
+  </chapter>
+
   <chapter id="devfs">
      <title>The Device File System</title>
 !Efs/devfs/base.c
@@ -403,7 +436,6 @@ X!Edrivers/pnp/system.c
      </sect1>
   </chapter>
 
-
   <chapter id="blkdev">
      <title>Block Devices</title>
 !Eblock/ll_rw_blk.c
@@ -414,6 +446,14 @@ X!Edrivers/pnp/system.c
 !Edrivers/char/misc.c
   </chapter>
 
+  <chapter id="parportdev">
+     <title>Parallel Port Devices</title>
+!Iinclude/linux/parport.h
+!Edrivers/parport/ieee1284.c
+!Edrivers/parport/share.c
+!Idrivers/parport/daisy.c
+  </chapter>
+
   <chapter id="viddev">
      <title>Video4Linux</title>
 !Edrivers/media/video/videodev.c

trunk/Documentation/DocBook/kernel-locking.tmpl

@@ -1590,7 +1590,7 @@ the amount of locking which needs to be done.
     <para>
       Our final dilemma is this: when can we actually destroy the
       removed element?  Remember, a reader might be stepping through
-      this element in the list right now: it we free this element and
+      this element in the list right now: if we free this element and
       the <symbol>next</symbol> pointer changes, the reader will jump
       off into garbage and crash.  We need to wait until we know that
       all the readers who were traversing the list when we deleted the

trunk/Documentation/RCU/checklist.txt

@@ -144,9 +144,47 @@ over a rather long period of time, but improvements are always welcome!
 	whether the increased speed is worth it.
 
 8.	Although synchronize_rcu() is a bit slower than is call_rcu(),
-	it usually results in simpler code.  So, unless update performance
-	is important or the updaters cannot block, synchronize_rcu()
-	should be used in preference to call_rcu().
+	it usually results in simpler code.  So, unless update
+	performance is critically important or the updaters cannot block,
+	synchronize_rcu() should be used in preference to call_rcu().
+
+	An especially important property of the synchronize_rcu()
+	primitive is that it automatically self-limits: if grace periods
+	are delayed for whatever reason, then the synchronize_rcu()
+	primitive will correspondingly delay updates.  In contrast,
+	code using call_rcu() should explicitly limit update rate in
+	cases where grace periods are delayed, as failing to do so can
+	result in excessive realtime latencies or even OOM conditions.
+
+	Ways of gaining this self-limiting property when using call_rcu()
+	include:
+
+	a.	Keeping a count of the number of data-structure elements
+		used by the RCU-protected data structure, including those
+		waiting for a grace period to elapse.  Enforce a limit
+		on this number, stalling updates as needed to allow
+		previously deferred frees to complete.
+
+		Alternatively, limit only the number awaiting deferred
+		free rather than the total number of elements.
+
+	b.	Limiting update rate.  For example, if updates occur only
+		once per hour, then no explicit rate limiting is required,
+		unless your system is already badly broken.  The dcache
+		subsystem takes this approach -- updates are guarded
+		by a global lock, limiting their rate.
+
+	c.	Trusted update -- if updates can only be done manually by
+		superuser or some other trusted user, then it might not
+		be necessary to automatically limit them.  The theory
+		here is that superuser already has lots of ways to crash
+		the machine.
+
+	d.	Use call_rcu_bh() rather than call_rcu(), in order to take
+		advantage of call_rcu_bh()'s faster grace periods.
+
+	e.	Periodically invoke synchronize_rcu(), permitting a limited
+		number of updates per grace period.
 
 9.	All RCU list-traversal primitives, which include
 	list_for_each_rcu(), list_for_each_entry_rcu(),

trunk/Documentation/RCU/whatisRCU.txt

@@ -184,7 +184,17 @@ synchronize_rcu()
 	blocking, it registers a function and argument which are invoked
 	after all ongoing RCU read-side critical sections have completed.
 	This callback variant is particularly useful in situations where
-	it is illegal to block.
+	it is illegal to block or where update-side performance is
+	critically important.
+
+	However, the call_rcu() API should not be used lightly, as use
+	of the synchronize_rcu() API generally results in simpler code.
+	In addition, the synchronize_rcu() API has the nice property
+	of automatically limiting update rate should grace periods
+	be delayed.  This property results in system resilience in face
+	of denial-of-service attacks.  Code using call_rcu() should limit
+	update rate in order to gain this same sort of resilience.  See
+	checklist.txt for some approaches to limiting the update rate.
 
 rcu_assign_pointer()
 

trunk/Documentation/atomic_ops.txt

@@ -157,13 +157,13 @@ For example, smp_mb__before_atomic_dec() can be used like so:
 	smp_mb__before_atomic_dec();
 	atomic_dec(&obj->ref_count);
 
-It makes sure that all memory operations preceeding the atomic_dec()
+It makes sure that all memory operations preceding the atomic_dec()
 call are strongly ordered with respect to the atomic counter
-operation.  In the above example, it guarentees that the assignment of
+operation.  In the above example, it guarantees that the assignment of
 "1" to obj->dead will be globally visible to other cpus before the
 atomic counter decrement.
 
-Without the explicitl smp_mb__before_atomic_dec() call, the
+Without the explicit smp_mb__before_atomic_dec() call, the
 implementation could legally allow the atomic counter update visible
 to other cpus before the "obj->dead = 1;" assignment.
 
@@ -173,11 +173,11 @@ ordering with respect to memory operations after an atomic_dec() call
 (smp_mb__{before,after}_atomic_inc()).
 
 A missing memory barrier in the cases where they are required by the
-atomic_t implementation above can have disasterous results.  Here is
-an example, which follows a pattern occuring frequently in the Linux
+atomic_t implementation above can have disastrous results.  Here is
+an example, which follows a pattern occurring frequently in the Linux
 kernel.  It is the use of atomic counters to implement reference
 counting, and it works such that once the counter falls to zero it can
-be guarenteed that no other entity can be accessing the object:
+be guaranteed that no other entity can be accessing the object:
 
 static void obj_list_add(struct obj *obj)
 {
@@ -291,19 +291,19 @@ to the size of an "unsigned long" C data type, and are least of that
 size.  The endianness of the bits within each "unsigned long" are the
 native endianness of the cpu.
 
-	void set_bit(unsigned long nr, volatils unsigned long *addr);
-	void clear_bit(unsigned long nr, volatils unsigned long *addr);
-	void change_bit(unsigned long nr, volatils unsigned long *addr);
+	void set_bit(unsigned long nr, volatile unsigned long *addr);
+	void clear_bit(unsigned long nr, volatile unsigned long *addr);
+	void change_bit(unsigned long nr, volatile unsigned long *addr);
 
 These routines set, clear, and change, respectively, the bit number
 indicated by "nr" on the bit mask pointed to by "ADDR".
 
 They must execute atomically, yet there are no implicit memory barrier
 semantics required of these interfaces.
 
-	int test_and_set_bit(unsigned long nr, volatils unsigned long *addr);
-	int test_and_clear_bit(unsigned long nr, volatils unsigned long *addr);
-	int test_and_change_bit(unsigned long nr, volatils unsigned long *addr);
+	int test_and_set_bit(unsigned long nr, volatile unsigned long *addr);
+	int test_and_clear_bit(unsigned long nr, volatile unsigned long *addr);
+	int test_and_change_bit(unsigned long nr, volatile unsigned long *addr);
 
 Like the above, except that these routines return a boolean which
 indicates whether the changed bit was set _BEFORE_ the atomic bit
@@ -335,7 +335,7 @@ subsequent memory operation is made visible.  For example:
 		/* ... */;
 	obj->killed = 1;
 
-The implementation of test_and_set_bit() must guarentee that
+The implementation of test_and_set_bit() must guarantee that
 "obj->dead = 1;" is visible to cpus before the atomic memory operation
 done by test_and_set_bit() becomes visible.  Likewise, the atomic
 memory operation done by test_and_set_bit() must become visible before
@@ -474,7 +474,7 @@ Now, as far as memory barriers go, as long as spin_lock()
 strictly orders all subsequent memory operations (including
 the cas()) with respect to itself, things will be fine.
 
-Said another way, _atomic_dec_and_lock() must guarentee that
+Said another way, _atomic_dec_and_lock() must guarantee that
 a counter dropping to zero is never made visible before the
 spinlock being acquired.