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-rw-r--r--Documentation/cgroups/cpuacct.txt18
-rw-r--r--Documentation/feature-removal-schedule.txt9
-rw-r--r--Documentation/infiniband/ipoib.txt45
-rw-r--r--Documentation/trace/ftrace.txt (renamed from Documentation/ftrace.txt)0
-rw-r--r--Documentation/trace/kmemtrace.txt (renamed from Documentation/vm/kmemtrace.txt)0
-rw-r--r--Documentation/trace/mmiotrace.txt (renamed from Documentation/tracers/mmiotrace.txt)0
-rw-r--r--Documentation/trace/tracepoints.txt (renamed from Documentation/tracepoints.txt)0
7 files changed, 72 insertions, 0 deletions
diff --git a/Documentation/cgroups/cpuacct.txt b/Documentation/cgroups/cpuacct.txt
index bb775fbe43d7..8b930946c52a 100644
--- a/Documentation/cgroups/cpuacct.txt
+++ b/Documentation/cgroups/cpuacct.txt
@@ -30,3 +30,21 @@ The above steps create a new group g1 and move the current shell
30process (bash) into it. CPU time consumed by this bash and its children 30process (bash) into it. CPU time consumed by this bash and its children
31can be obtained from g1/cpuacct.usage and the same is accumulated in 31can be obtained from g1/cpuacct.usage and the same is accumulated in
32/cgroups/cpuacct.usage also. 32/cgroups/cpuacct.usage also.
33
34cpuacct.stat file lists a few statistics which further divide the
35CPU time obtained by the cgroup into user and system times. Currently
36the following statistics are supported:
37
38user: Time spent by tasks of the cgroup in user mode.
39system: Time spent by tasks of the cgroup in kernel mode.
40
41user and system are in USER_HZ unit.
42
43cpuacct controller uses percpu_counter interface to collect user and
44system times. This has two side effects:
45
46- It is theoretically possible to see wrong values for user and system times.
47 This is because percpu_counter_read() on 32bit systems isn't safe
48 against concurrent writes.
49- It is possible to see slightly outdated values for user and system times
50 due to the batch processing nature of percpu_counter.
diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt
index 7e2af10e8264..de491a3e2313 100644
--- a/Documentation/feature-removal-schedule.txt
+++ b/Documentation/feature-removal-schedule.txt
@@ -428,3 +428,12 @@ Why: In 2.6.27, the semantics of /sys/bus/pci/slots was redefined to
428 After a reasonable transition period, we will remove the legacy 428 After a reasonable transition period, we will remove the legacy
429 fakephp interface. 429 fakephp interface.
430Who: Alex Chiang <achiang@hp.com> 430Who: Alex Chiang <achiang@hp.com>
431
432---------------------------
433
434What: i2c-voodoo3 driver
435When: October 2009
436Why: Superseded by tdfxfb. I2C/DDC support used to live in a separate
437 driver but this caused driver conflicts.
438Who: Jean Delvare <khali@linux-fr.org>
439 Krzysztof Helt <krzysztof.h1@wp.pl>
diff --git a/Documentation/infiniband/ipoib.txt b/Documentation/infiniband/ipoib.txt
index 864ff3283780..6d40f00b358c 100644
--- a/Documentation/infiniband/ipoib.txt
+++ b/Documentation/infiniband/ipoib.txt
@@ -24,6 +24,49 @@ Partitions and P_Keys
24 The P_Key for any interface is given by the "pkey" file, and the 24 The P_Key for any interface is given by the "pkey" file, and the
25 main interface for a subinterface is in "parent." 25 main interface for a subinterface is in "parent."
26 26
27Datagram vs Connected modes
28
29 The IPoIB driver supports two modes of operation: datagram and
30 connected. The mode is set and read through an interface's
31 /sys/class/net/<intf name>/mode file.
32
33 In datagram mode, the IB UD (Unreliable Datagram) transport is used
34 and so the interface MTU has is equal to the IB L2 MTU minus the
35 IPoIB encapsulation header (4 bytes). For example, in a typical IB
36 fabric with a 2K MTU, the IPoIB MTU will be 2048 - 4 = 2044 bytes.
37
38 In connected mode, the IB RC (Reliable Connected) transport is used.
39 Connected mode is to takes advantage of the connected nature of the
40 IB transport and allows an MTU up to the maximal IP packet size of
41 64K, which reduces the number of IP packets needed for handling
42 large UDP datagrams, TCP segments, etc and increases the performance
43 for large messages.
44
45 In connected mode, the interface's UD QP is still used for multicast
46 and communication with peers that don't support connected mode. In
47 this case, RX emulation of ICMP PMTU packets is used to cause the
48 networking stack to use the smaller UD MTU for these neighbours.
49
50Stateless offloads
51
52 If the IB HW supports IPoIB stateless offloads, IPoIB advertises
53 TCP/IP checksum and/or Large Send (LSO) offloading capability to the
54 network stack.
55
56 Large Receive (LRO) offloading is also implemented and may be turned
57 on/off using ethtool calls. Currently LRO is supported only for
58 checksum offload capable devices.
59
60 Stateless offloads are supported only in datagram mode.
61
62Interrupt moderation
63
64 If the underlying IB device supports CQ event moderation, one can
65 use ethtool to set interrupt mitigation parameters and thus reduce
66 the overhead incurred by handling interrupts. The main code path of
67 IPoIB doesn't use events for TX completion signaling so only RX
68 moderation is supported.
69
27Debugging Information 70Debugging Information
28 71
29 By compiling the IPoIB driver with CONFIG_INFINIBAND_IPOIB_DEBUG set 72 By compiling the IPoIB driver with CONFIG_INFINIBAND_IPOIB_DEBUG set
@@ -55,3 +98,5 @@ References
55 http://ietf.org/rfc/rfc4391.txt 98 http://ietf.org/rfc/rfc4391.txt
56 IP over InfiniBand (IPoIB) Architecture (RFC 4392) 99 IP over InfiniBand (IPoIB) Architecture (RFC 4392)
57 http://ietf.org/rfc/rfc4392.txt 100 http://ietf.org/rfc/rfc4392.txt
101 IP over InfiniBand: Connected Mode (RFC 4755)
102 http://ietf.org/rfc/rfc4755.txt
diff --git a/Documentation/ftrace.txt b/Documentation/trace/ftrace.txt
index fd9a3e693813..fd9a3e693813 100644
--- a/Documentation/ftrace.txt
+++ b/Documentation/trace/ftrace.txt
diff --git a/Documentation/vm/kmemtrace.txt b/Documentation/trace/kmemtrace.txt
index a956d9b7f943..a956d9b7f943 100644
--- a/Documentation/vm/kmemtrace.txt
+++ b/Documentation/trace/kmemtrace.txt
diff --git a/Documentation/tracers/mmiotrace.txt b/Documentation/trace/mmiotrace.txt
index 5731c67abc55..5731c67abc55 100644
--- a/Documentation/tracers/mmiotrace.txt
+++ b/Documentation/trace/mmiotrace.txt
diff --git a/Documentation/tracepoints.txt b/Documentation/trace/tracepoints.txt
index c0e1ceed75a4..c0e1ceed75a4 100644
--- a/Documentation/tracepoints.txt
+++ b/Documentation/trace/tracepoints.txt