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authorIngo Molnar <mingo@elte.hu>2009-06-11 17:31:52 -0400
committerIngo Molnar <mingo@elte.hu>2009-06-11 17:31:52 -0400
commit0d5959723e1db3fd7323c198a50c16cecf96c7a9 (patch)
tree802b623fff261ebcbbddadf84af5524398364a18 /Documentation
parent62fdac5913f71f8f200bd2c9bd59a02e9a1498e9 (diff)
parent512626a04e72aca60effe111fa0333ed0b195d21 (diff)
Merge branch 'linus' into x86/mce3
Conflicts: arch/x86/kernel/cpu/mcheck/mce_64.c arch/x86/kernel/irq.c Merge reason: Resolve the conflicts above. Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/ABI/testing/sysfs-block59
-rw-r--r--Documentation/ABI/testing/sysfs-bus-pci-devices-cciss33
-rw-r--r--Documentation/ABI/testing/sysfs-devices-cache_disable18
-rw-r--r--Documentation/DMA-API.txt12
-rw-r--r--Documentation/DocBook/Makefile3
-rw-r--r--Documentation/DocBook/tracepoint.tmpl89
-rw-r--r--Documentation/RCU/trace.txt102
-rw-r--r--Documentation/Smack.txt20
-rw-r--r--Documentation/block/biodoc.txt2
-rw-r--r--Documentation/filesystems/gfs2-glocks.txt2
-rw-r--r--Documentation/filesystems/gfs2.txt19
-rw-r--r--Documentation/futex-requeue-pi.txt131
-rw-r--r--Documentation/kernel-parameters.txt57
-rw-r--r--Documentation/kmemleak.txt142
-rw-r--r--Documentation/memory-barriers.txt129
-rw-r--r--Documentation/scheduler/sched-rt-group.txt20
-rw-r--r--Documentation/sysctl/kernel.txt11
-rw-r--r--Documentation/trace/events.txt90
-rw-r--r--Documentation/trace/ftrace.txt17
-rw-r--r--Documentation/trace/power.txt17
-rw-r--r--Documentation/x86/boot.txt122
-rw-r--r--Documentation/x86/x86_64/boot-options.txt5
-rw-r--r--Documentation/x86/x86_64/mm.txt9
23 files changed, 1034 insertions, 75 deletions
diff --git a/Documentation/ABI/testing/sysfs-block b/Documentation/ABI/testing/sysfs-block
index 44f52a4f590..cbbd3e06994 100644
--- a/Documentation/ABI/testing/sysfs-block
+++ b/Documentation/ABI/testing/sysfs-block
@@ -60,3 +60,62 @@ Description:
60 Indicates whether the block layer should automatically 60 Indicates whether the block layer should automatically
61 generate checksums for write requests bound for 61 generate checksums for write requests bound for
62 devices that support receiving integrity metadata. 62 devices that support receiving integrity metadata.
63
64What: /sys/block/<disk>/alignment_offset
65Date: April 2009
66Contact: Martin K. Petersen <martin.petersen@oracle.com>
67Description:
68 Storage devices may report a physical block size that is
69 bigger than the logical block size (for instance a drive
70 with 4KB physical sectors exposing 512-byte logical
71 blocks to the operating system). This parameter
72 indicates how many bytes the beginning of the device is
73 offset from the disk's natural alignment.
74
75What: /sys/block/<disk>/<partition>/alignment_offset
76Date: April 2009
77Contact: Martin K. Petersen <martin.petersen@oracle.com>
78Description:
79 Storage devices may report a physical block size that is
80 bigger than the logical block size (for instance a drive
81 with 4KB physical sectors exposing 512-byte logical
82 blocks to the operating system). This parameter
83 indicates how many bytes the beginning of the partition
84 is offset from the disk's natural alignment.
85
86What: /sys/block/<disk>/queue/logical_block_size
87Date: May 2009
88Contact: Martin K. Petersen <martin.petersen@oracle.com>
89Description:
90 This is the smallest unit the storage device can
91 address. It is typically 512 bytes.
92
93What: /sys/block/<disk>/queue/physical_block_size
94Date: May 2009
95Contact: Martin K. Petersen <martin.petersen@oracle.com>
96Description:
97 This is the smallest unit the storage device can write
98 without resorting to read-modify-write operation. It is
99 usually the same as the logical block size but may be
100 bigger. One example is SATA drives with 4KB sectors
101 that expose a 512-byte logical block size to the
102 operating system.
103
104What: /sys/block/<disk>/queue/minimum_io_size
105Date: April 2009
106Contact: Martin K. Petersen <martin.petersen@oracle.com>
107Description:
108 Storage devices may report a preferred minimum I/O size,
109 which is the smallest request the device can perform
110 without incurring a read-modify-write penalty. For disk
111 drives this is often the physical block size. For RAID
112 arrays it is often the stripe chunk size.
113
114What: /sys/block/<disk>/queue/optimal_io_size
115Date: April 2009
116Contact: Martin K. Petersen <martin.petersen@oracle.com>
117Description:
118 Storage devices may report an optimal I/O size, which is
119 the device's preferred unit of receiving I/O. This is
120 rarely reported for disk drives. For RAID devices it is
121 usually the stripe width or the internal block size.
diff --git a/Documentation/ABI/testing/sysfs-bus-pci-devices-cciss b/Documentation/ABI/testing/sysfs-bus-pci-devices-cciss
new file mode 100644
index 00000000000..0a92a7c93a6
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-bus-pci-devices-cciss
@@ -0,0 +1,33 @@
1Where: /sys/bus/pci/devices/<dev>/ccissX/cXdY/model
2Date: March 2009
3Kernel Version: 2.6.30
4Contact: iss_storagedev@hp.com
5Description: Displays the SCSI INQUIRY page 0 model for logical drive
6 Y of controller X.
7
8Where: /sys/bus/pci/devices/<dev>/ccissX/cXdY/rev
9Date: March 2009
10Kernel Version: 2.6.30
11Contact: iss_storagedev@hp.com
12Description: Displays the SCSI INQUIRY page 0 revision for logical
13 drive Y of controller X.
14
15Where: /sys/bus/pci/devices/<dev>/ccissX/cXdY/unique_id
16Date: March 2009
17Kernel Version: 2.6.30
18Contact: iss_storagedev@hp.com
19Description: Displays the SCSI INQUIRY page 83 serial number for logical
20 drive Y of controller X.
21
22Where: /sys/bus/pci/devices/<dev>/ccissX/cXdY/vendor
23Date: March 2009
24Kernel Version: 2.6.30
25Contact: iss_storagedev@hp.com
26Description: Displays the SCSI INQUIRY page 0 vendor for logical drive
27 Y of controller X.
28
29Where: /sys/bus/pci/devices/<dev>/ccissX/cXdY/block:cciss!cXdY
30Date: March 2009
31Kernel Version: 2.6.30
32Contact: iss_storagedev@hp.com
33Description: A symbolic link to /sys/block/cciss!cXdY
diff --git a/Documentation/ABI/testing/sysfs-devices-cache_disable b/Documentation/ABI/testing/sysfs-devices-cache_disable
new file mode 100644
index 00000000000..175bb4f7051
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-devices-cache_disable
@@ -0,0 +1,18 @@
1What: /sys/devices/system/cpu/cpu*/cache/index*/cache_disable_X
2Date: August 2008
3KernelVersion: 2.6.27
4Contact: mark.langsdorf@amd.com
5Description: These files exist in every cpu's cache index directories.
6 There are currently 2 cache_disable_# files in each
7 directory. Reading from these files on a supported
8 processor will return that cache disable index value
9 for that processor and node. Writing to one of these
10 files will cause the specificed cache index to be disabled.
11
12 Currently, only AMD Family 10h Processors support cache index
13 disable, and only for their L3 caches. See the BIOS and
14 Kernel Developer's Guide at
15 http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/31116-Public-GH-BKDG_3.20_2-4-09.pdf
16 for formatting information and other details on the
17 cache index disable.
18Users: joachim.deguara@amd.com
diff --git a/Documentation/DMA-API.txt b/Documentation/DMA-API.txt
index d9aa43d78bc..25fb8bcf32a 100644
--- a/Documentation/DMA-API.txt
+++ b/Documentation/DMA-API.txt
@@ -704,12 +704,24 @@ this directory the following files can currently be found:
704 The current number of free dma_debug_entries 704 The current number of free dma_debug_entries
705 in the allocator. 705 in the allocator.
706 706
707 dma-api/driver-filter
708 You can write a name of a driver into this file
709 to limit the debug output to requests from that
710 particular driver. Write an empty string to
711 that file to disable the filter and see
712 all errors again.
713
707If you have this code compiled into your kernel it will be enabled by default. 714If you have this code compiled into your kernel it will be enabled by default.
708If you want to boot without the bookkeeping anyway you can provide 715If you want to boot without the bookkeeping anyway you can provide
709'dma_debug=off' as a boot parameter. This will disable DMA-API debugging. 716'dma_debug=off' as a boot parameter. This will disable DMA-API debugging.
710Notice that you can not enable it again at runtime. You have to reboot to do 717Notice that you can not enable it again at runtime. You have to reboot to do
711so. 718so.
712 719
720If you want to see debug messages only for a special device driver you can
721specify the dma_debug_driver=<drivername> parameter. This will enable the
722driver filter at boot time. The debug code will only print errors for that
723driver afterwards. This filter can be disabled or changed later using debugfs.
724
713When the code disables itself at runtime this is most likely because it ran 725When the code disables itself at runtime this is most likely because it ran
714out of dma_debug_entries. These entries are preallocated at boot. The number 726out of dma_debug_entries. These entries are preallocated at boot. The number
715of preallocated entries is defined per architecture. If it is too low for you 727of preallocated entries is defined per architecture. If it is too low for you
diff --git a/Documentation/DocBook/Makefile b/Documentation/DocBook/Makefile
index b1eb661e630..9632444f6c6 100644
--- a/Documentation/DocBook/Makefile
+++ b/Documentation/DocBook/Makefile
@@ -13,7 +13,8 @@ DOCBOOKS := z8530book.xml mcabook.xml device-drivers.xml \
13 gadget.xml libata.xml mtdnand.xml librs.xml rapidio.xml \ 13 gadget.xml libata.xml mtdnand.xml librs.xml rapidio.xml \
14 genericirq.xml s390-drivers.xml uio-howto.xml scsi.xml \ 14 genericirq.xml s390-drivers.xml uio-howto.xml scsi.xml \
15 mac80211.xml debugobjects.xml sh.xml regulator.xml \ 15 mac80211.xml debugobjects.xml sh.xml regulator.xml \
16 alsa-driver-api.xml writing-an-alsa-driver.xml 16 alsa-driver-api.xml writing-an-alsa-driver.xml \
17 tracepoint.xml
17 18
18### 19###
19# The build process is as follows (targets): 20# The build process is as follows (targets):
diff --git a/Documentation/DocBook/tracepoint.tmpl b/Documentation/DocBook/tracepoint.tmpl
new file mode 100644
index 00000000000..b0756d0fd57
--- /dev/null
+++ b/Documentation/DocBook/tracepoint.tmpl
@@ -0,0 +1,89 @@
1<?xml version="1.0" encoding="UTF-8"?>
2<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN"
3 "http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd" []>
4
5<book id="Tracepoints">
6 <bookinfo>
7 <title>The Linux Kernel Tracepoint API</title>
8
9 <authorgroup>
10 <author>
11 <firstname>Jason</firstname>
12 <surname>Baron</surname>
13 <affiliation>
14 <address>
15 <email>jbaron@redhat.com</email>
16 </address>
17 </affiliation>
18 </author>
19 </authorgroup>
20
21 <legalnotice>
22 <para>
23 This documentation is free software; you can redistribute
24 it and/or modify it under the terms of the GNU General Public
25 License as published by the Free Software Foundation; either
26 version 2 of the License, or (at your option) any later
27 version.
28 </para>
29
30 <para>
31 This program is distributed in the hope that it will be
32 useful, but WITHOUT ANY WARRANTY; without even the implied
33 warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
34 See the GNU General Public License for more details.
35 </para>
36
37 <para>
38 You should have received a copy of the GNU General Public
39 License along with this program; if not, write to the Free
40 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston,
41 MA 02111-1307 USA
42 </para>
43
44 <para>
45 For more details see the file COPYING in the source
46 distribution of Linux.
47 </para>
48 </legalnotice>
49 </bookinfo>
50
51 <toc></toc>
52 <chapter id="intro">
53 <title>Introduction</title>
54 <para>
55 Tracepoints are static probe points that are located in strategic points
56 throughout the kernel. 'Probes' register/unregister with tracepoints
57 via a callback mechanism. The 'probes' are strictly typed functions that
58 are passed a unique set of parameters defined by each tracepoint.
59 </para>
60
61 <para>
62 From this simple callback mechanism, 'probes' can be used to profile, debug,
63 and understand kernel behavior. There are a number of tools that provide a
64 framework for using 'probes'. These tools include Systemtap, ftrace, and
65 LTTng.
66 </para>
67
68 <para>
69 Tracepoints are defined in a number of header files via various macros. Thus,
70 the purpose of this document is to provide a clear accounting of the available
71 tracepoints. The intention is to understand not only what tracepoints are
72 available but also to understand where future tracepoints might be added.
73 </para>
74
75 <para>
76 The API presented has functions of the form:
77 <function>trace_tracepointname(function parameters)</function>. These are the
78 tracepoints callbacks that are found throughout the code. Registering and
79 unregistering probes with these callback sites is covered in the
80 <filename>Documentation/trace/*</filename> directory.
81 </para>
82 </chapter>
83
84 <chapter id="irq">
85 <title>IRQ</title>
86!Iinclude/trace/events/irq.h
87 </chapter>
88
89</book>
diff --git a/Documentation/RCU/trace.txt b/Documentation/RCU/trace.txt
index 068848240a8..02cced183b2 100644
--- a/Documentation/RCU/trace.txt
+++ b/Documentation/RCU/trace.txt
@@ -192,23 +192,24 @@ rcu/rcuhier (which displays the struct rcu_node hierarchy).
192The output of "cat rcu/rcudata" looks as follows: 192The output of "cat rcu/rcudata" looks as follows:
193 193
194rcu: 194rcu:
195 0 c=4011 g=4012 pq=1 pqc=4011 qp=0 rpfq=1 rp=3c2a dt=23301/73 dn=2 df=1882 of=0 ri=2126 ql=2 b=10 195rcu:
196 1 c=4011 g=4012 pq=1 pqc=4011 qp=0 rpfq=3 rp=39a6 dt=78073/1 dn=2 df=1402 of=0 ri=1875 ql=46 b=10 196 0 c=17829 g=17829 pq=1 pqc=17829 qp=0 dt=10951/1 dn=0 df=1101 of=0 ri=36 ql=0 b=10
197 2 c=4010 g=4010 pq=1 pqc=4010 qp=0 rpfq=-5 rp=1d12 dt=16646/0 dn=2 df=3140 of=0 ri=2080 ql=0 b=10 197 1 c=17829 g=17829 pq=1 pqc=17829 qp=0 dt=16117/1 dn=0 df=1015 of=0 ri=0 ql=0 b=10
198 3 c=4012 g=4013 pq=1 pqc=4012 qp=1 rpfq=3 rp=2b50 dt=21159/1 dn=2 df=2230 of=0 ri=1923 ql=72 b=10 198 2 c=17829 g=17829 pq=1 pqc=17829 qp=0 dt=1445/1 dn=0 df=1839 of=0 ri=0 ql=0 b=10
199 4 c=4012 g=4013 pq=1 pqc=4012 qp=1 rpfq=3 rp=1644 dt=5783/1 dn=2 df=3348 of=0 ri=2805 ql=7 b=10 199 3 c=17829 g=17829 pq=1 pqc=17829 qp=0 dt=6681/1 dn=0 df=1545 of=0 ri=0 ql=0 b=10
200 5 c=4012 g=4013 pq=0 pqc=4011 qp=1 rpfq=3 rp=1aac dt=5879/1 dn=2 df=3140 of=0 ri=2066 ql=10 b=10 200 4 c=17829 g=17829 pq=1 pqc=17829 qp=0 dt=1003/1 dn=0 df=1992 of=0 ri=0 ql=0 b=10
201 6 c=4012 g=4013 pq=1 pqc=4012 qp=1 rpfq=3 rp=ed8 dt=5847/1 dn=2 df=3797 of=0 ri=1266 ql=10 b=10 201 5 c=17829 g=17830 pq=1 pqc=17829 qp=1 dt=3887/1 dn=0 df=3331 of=0 ri=4 ql=2 b=10
202 7 c=4012 g=4013 pq=1 pqc=4012 qp=1 rpfq=3 rp=1fa2 dt=6199/1 dn=2 df=2795 of=0 ri=2162 ql=28 b=10 202 6 c=17829 g=17829 pq=1 pqc=17829 qp=0 dt=859/1 dn=0 df=3224 of=0 ri=0 ql=0 b=10
203 7 c=17829 g=17830 pq=0 pqc=17829 qp=1 dt=3761/1 dn=0 df=1818 of=0 ri=0 ql=2 b=10
203rcu_bh: 204rcu_bh:
204 0 c=-268 g=-268 pq=1 pqc=-268 qp=0 rpfq=-145 rp=21d6 dt=23301/73 dn=2 df=0 of=0 ri=0 ql=0 b=10 205 0 c=-275 g=-275 pq=1 pqc=-275 qp=0 dt=10951/1 dn=0 df=0 of=0 ri=0 ql=0 b=10
205 1 c=-268 g=-268 pq=1 pqc=-268 qp=1 rpfq=-170 rp=20ce dt=78073/1 dn=2 df=26 of=0 ri=5 ql=0 b=10 206 1 c=-275 g=-275 pq=1 pqc=-275 qp=0 dt=16117/1 dn=0 df=13 of=0 ri=0 ql=0 b=10
206 2 c=-268 g=-268 pq=1 pqc=-268 qp=1 rpfq=-83 rp=fbd dt=16646/0 dn=2 df=28 of=0 ri=4 ql=0 b=10 207 2 c=-275 g=-275 pq=1 pqc=-275 qp=0 dt=1445/1 dn=0 df=15 of=0 ri=0 ql=0 b=10
207 3 c=-268 g=-268 pq=1 pqc=-268 qp=0 rpfq=-105 rp=178c dt=21159/1 dn=2 df=28 of=0 ri=2 ql=0 b=10 208 3 c=-275 g=-275 pq=1 pqc=-275 qp=0 dt=6681/1 dn=0 df=9 of=0 ri=0 ql=0 b=10
208 4 c=-268 g=-268 pq=1 pqc=-268 qp=1 rpfq=-30 rp=b54 dt=5783/1 dn=2 df=32 of=0 ri=0 ql=0 b=10 209 4 c=-275 g=-275 pq=1 pqc=-275 qp=0 dt=1003/1 dn=0 df=15 of=0 ri=0 ql=0 b=10
209 5 c=-268 g=-268 pq=1 pqc=-268 qp=1 rpfq=-29 rp=df5 dt=5879/1 dn=2 df=30 of=0 ri=3 ql=0 b=10 210 5 c=-275 g=-275 pq=1 pqc=-275 qp=0 dt=3887/1 dn=0 df=15 of=0 ri=0 ql=0 b=10
210 6 c=-268 g=-268 pq=1 pqc=-268 qp=1 rpfq=-28 rp=788 dt=5847/1 dn=2 df=32 of=0 ri=0 ql=0 b=10 211 6 c=-275 g=-275 pq=1 pqc=-275 qp=0 dt=859/1 dn=0 df=15 of=0 ri=0 ql=0 b=10
211 7 c=-268 g=-268 pq=1 pqc=-268 qp=1 rpfq=-53 rp=1098 dt=6199/1 dn=2 df=30 of=0 ri=3 ql=0 b=10 212 7 c=-275 g=-275 pq=1 pqc=-275 qp=0 dt=3761/1 dn=0 df=15 of=0 ri=0 ql=0 b=10
212 213
213The first section lists the rcu_data structures for rcu, the second for 214The first section lists the rcu_data structures for rcu, the second for
214rcu_bh. Each section has one line per CPU, or eight for this 8-CPU system. 215rcu_bh. Each section has one line per CPU, or eight for this 8-CPU system.
@@ -253,12 +254,6 @@ o "pqc" indicates which grace period the last-observed quiescent
253o "qp" indicates that RCU still expects a quiescent state from 254o "qp" indicates that RCU still expects a quiescent state from
254 this CPU. 255 this CPU.
255 256
256o "rpfq" is the number of rcu_pending() calls on this CPU required
257 to induce this CPU to invoke force_quiescent_state().
258
259o "rp" is low-order four hex digits of the count of how many times
260 rcu_pending() has been invoked on this CPU.
261
262o "dt" is the current value of the dyntick counter that is incremented 257o "dt" is the current value of the dyntick counter that is incremented
263 when entering or leaving dynticks idle state, either by the 258 when entering or leaving dynticks idle state, either by the
264 scheduler or by irq. The number after the "/" is the interrupt 259 scheduler or by irq. The number after the "/" is the interrupt
@@ -305,6 +300,9 @@ o "b" is the batch limit for this CPU. If more than this number
305 of RCU callbacks is ready to invoke, then the remainder will 300 of RCU callbacks is ready to invoke, then the remainder will
306 be deferred. 301 be deferred.
307 302
303There is also an rcu/rcudata.csv file with the same information in
304comma-separated-variable spreadsheet format.
305
308 306
309The output of "cat rcu/rcugp" looks as follows: 307The output of "cat rcu/rcugp" looks as follows:
310 308
@@ -411,3 +409,63 @@ o Each element of the form "1/1 0:127 ^0" represents one struct
411 For example, the first entry at the lowest level shows 409 For example, the first entry at the lowest level shows
412 "^0", indicating that it corresponds to bit zero in 410 "^0", indicating that it corresponds to bit zero in
413 the first entry at the middle level. 411 the first entry at the middle level.
412
413
414The output of "cat rcu/rcu_pending" looks as follows:
415
416rcu:
417 0 np=255892 qsp=53936 cbr=0 cng=14417 gpc=10033 gps=24320 nf=6445 nn=146741
418 1 np=261224 qsp=54638 cbr=0 cng=25723 gpc=16310 gps=2849 nf=5912 nn=155792
419 2 np=237496 qsp=49664 cbr=0 cng=2762 gpc=45478 gps=1762 nf=1201 nn=136629
420 3 np=236249 qsp=48766 cbr=0 cng=286 gpc=48049 gps=1218 nf=207 nn=137723
421 4 np=221310 qsp=46850 cbr=0 cng=26 gpc=43161 gps=4634 nf=3529 nn=123110
422 5 np=237332 qsp=48449 cbr=0 cng=54 gpc=47920 gps=3252 nf=201 nn=137456
423 6 np=219995 qsp=46718 cbr=0 cng=50 gpc=42098 gps=6093 nf=4202 nn=120834
424 7 np=249893 qsp=49390 cbr=0 cng=72 gpc=38400 gps=17102 nf=41 nn=144888
425rcu_bh:
426 0 np=146741 qsp=1419 cbr=0 cng=6 gpc=0 gps=0 nf=2 nn=145314
427 1 np=155792 qsp=12597 cbr=0 cng=0 gpc=4 gps=8 nf=3 nn=143180
428 2 np=136629 qsp=18680 cbr=0 cng=0 gpc=7 gps=6 nf=0 nn=117936
429 3 np=137723 qsp=2843 cbr=0 cng=0 gpc=10 gps=7 nf=0 nn=134863
430 4 np=123110 qsp=12433 cbr=0 cng=0 gpc=4 gps=2 nf=0 nn=110671
431 5 np=137456 qsp=4210 cbr=0 cng=0 gpc=6 gps=5 nf=0 nn=133235
432 6 np=120834 qsp=9902 cbr=0 cng=0 gpc=6 gps=3 nf=2 nn=110921
433 7 np=144888 qsp=26336 cbr=0 cng=0 gpc=8 gps=2 nf=0 nn=118542
434
435As always, this is once again split into "rcu" and "rcu_bh" portions.
436The fields are as follows:
437
438o "np" is the number of times that __rcu_pending() has been invoked
439 for the corresponding flavor of RCU.
440
441o "qsp" is the number of times that the RCU was waiting for a
442 quiescent state from this CPU.
443
444o "cbr" is the number of times that this CPU had RCU callbacks
445 that had passed through a grace period, and were thus ready
446 to be invoked.
447
448o "cng" is the number of times that this CPU needed another
449 grace period while RCU was idle.
450
451o "gpc" is the number of times that an old grace period had
452 completed, but this CPU was not yet aware of it.
453
454o "gps" is the number of times that a new grace period had started,
455 but this CPU was not yet aware of it.
456
457o "nf" is the number of times that this CPU suspected that the
458 current grace period had run for too long, and thus needed to
459 be forced.
460
461 Please note that "forcing" consists of sending resched IPIs
462 to holdout CPUs. If that CPU really still is in an old RCU
463 read-side critical section, then we really do have to wait for it.
464 The assumption behing "forcing" is that the CPU is not still in
465 an old RCU read-side critical section, but has not yet responded
466 for some other reason.
467
468o "nn" is the number of times that this CPU needed nothing. Alert
469 readers will note that the rcu "nn" number for a given CPU very
470 closely matches the rcu_bh "np" number for that same CPU. This
471 is due to short-circuit evaluation in rcu_pending().
diff --git a/Documentation/Smack.txt b/Documentation/Smack.txt
index 629c92e9978..34614b4c708 100644
--- a/Documentation/Smack.txt
+++ b/Documentation/Smack.txt
@@ -184,8 +184,9 @@ length. Single character labels using special characters, that being anything
184other than a letter or digit, are reserved for use by the Smack development 184other than a letter or digit, are reserved for use by the Smack development
185team. Smack labels are unstructured, case sensitive, and the only operation 185team. Smack labels are unstructured, case sensitive, and the only operation
186ever performed on them is comparison for equality. Smack labels cannot 186ever performed on them is comparison for equality. Smack labels cannot
187contain unprintable characters or the "/" (slash) character. Smack labels 187contain unprintable characters, the "/" (slash), the "\" (backslash), the "'"
188cannot begin with a '-', which is reserved for special options. 188(quote) and '"' (double-quote) characters.
189Smack labels cannot begin with a '-', which is reserved for special options.
189 190
190There are some predefined labels: 191There are some predefined labels:
191 192
@@ -523,3 +524,18 @@ Smack supports some mount options:
523 524
524These mount options apply to all file system types. 525These mount options apply to all file system types.
525 526
527Smack auditing
528
529If you want Smack auditing of security events, you need to set CONFIG_AUDIT
530in your kernel configuration.
531By default, all denied events will be audited. You can change this behavior by
532writing a single character to the /smack/logging file :
5330 : no logging
5341 : log denied (default)
5352 : log accepted
5363 : log denied & accepted
537
538Events are logged as 'key=value' pairs, for each event you at least will get
539the subjet, the object, the rights requested, the action, the kernel function
540that triggered the event, plus other pairs depending on the type of event
541audited.
diff --git a/Documentation/block/biodoc.txt b/Documentation/block/biodoc.txt
index 6fab97ea7e6..8d2158a1c6a 100644
--- a/Documentation/block/biodoc.txt
+++ b/Documentation/block/biodoc.txt
@@ -186,7 +186,7 @@ a virtual address mapping (unlike the earlier scheme of virtual address
186do not have a corresponding kernel virtual address space mapping) and 186do not have a corresponding kernel virtual address space mapping) and
187low-memory pages. 187low-memory pages.
188 188
189Note: Please refer to Documentation/PCI/PCI-DMA-mapping.txt for a discussion 189Note: Please refer to Documentation/DMA-mapping.txt for a discussion
190on PCI high mem DMA aspects and mapping of scatter gather lists, and support 190on PCI high mem DMA aspects and mapping of scatter gather lists, and support
191for 64 bit PCI. 191for 64 bit PCI.
192 192
diff --git a/Documentation/filesystems/gfs2-glocks.txt b/Documentation/filesystems/gfs2-glocks.txt
index 4dae9a3840b..0494f78d87e 100644
--- a/Documentation/filesystems/gfs2-glocks.txt
+++ b/Documentation/filesystems/gfs2-glocks.txt
@@ -60,7 +60,7 @@ go_lock | Called for the first local holder of a lock
60go_unlock | Called on the final local unlock of a lock 60go_unlock | Called on the final local unlock of a lock
61go_dump | Called to print content of object for debugfs file, or on 61go_dump | Called to print content of object for debugfs file, or on
62 | error to dump glock to the log. 62 | error to dump glock to the log.
63go_type; | The type of the glock, LM_TYPE_..... 63go_type | The type of the glock, LM_TYPE_.....
64go_min_hold_time | The minimum hold time 64go_min_hold_time | The minimum hold time
65 65
66The minimum hold time for each lock is the time after a remote lock 66The minimum hold time for each lock is the time after a remote lock
diff --git a/Documentation/filesystems/gfs2.txt b/Documentation/filesystems/gfs2.txt
index 593004b6bba..5e3ab8f3bef 100644
--- a/Documentation/filesystems/gfs2.txt
+++ b/Documentation/filesystems/gfs2.txt
@@ -11,18 +11,15 @@ their I/O so file system consistency is maintained. One of the nifty
11features of GFS is perfect consistency -- changes made to the file system 11features of GFS is perfect consistency -- changes made to the file system
12on one machine show up immediately on all other machines in the cluster. 12on one machine show up immediately on all other machines in the cluster.
13 13
14GFS uses interchangable inter-node locking mechanisms. Different lock 14GFS uses interchangable inter-node locking mechanisms, the currently
15modules can plug into GFS and each file system selects the appropriate 15supported mechanisms are:
16lock module at mount time. Lock modules include:
17 16
18 lock_nolock -- allows gfs to be used as a local file system 17 lock_nolock -- allows gfs to be used as a local file system
19 18
20 lock_dlm -- uses a distributed lock manager (dlm) for inter-node locking 19 lock_dlm -- uses a distributed lock manager (dlm) for inter-node locking
21 The dlm is found at linux/fs/dlm/ 20 The dlm is found at linux/fs/dlm/
22 21
23In addition to interfacing with an external locking manager, a gfs lock 22Lock_dlm depends on user space cluster management systems found
24module is responsible for interacting with external cluster management
25systems. Lock_dlm depends on user space cluster management systems found
26at the URL above. 23at the URL above.
27 24
28To use gfs as a local file system, no external clustering systems are 25To use gfs as a local file system, no external clustering systems are
@@ -31,13 +28,19 @@ needed, simply:
31 $ mkfs -t gfs2 -p lock_nolock -j 1 /dev/block_device 28 $ mkfs -t gfs2 -p lock_nolock -j 1 /dev/block_device
32 $ mount -t gfs2 /dev/block_device /dir 29 $ mount -t gfs2 /dev/block_device /dir
33 30
34GFS2 is not on-disk compatible with previous versions of GFS. 31If you are using Fedora, you need to install the gfs2-utils package
32and, for lock_dlm, you will also need to install the cman package
33and write a cluster.conf as per the documentation.
34
35GFS2 is not on-disk compatible with previous versions of GFS, but it
36is pretty close.
35 37
36The following man pages can be found at the URL above: 38The following man pages can be found at the URL above:
37 gfs2_fsck to repair a filesystem 39 fsck.gfs2 to repair a filesystem
38 gfs2_grow to expand a filesystem online 40 gfs2_grow to expand a filesystem online
39 gfs2_jadd to add journals to a filesystem online 41 gfs2_jadd to add journals to a filesystem online
40 gfs2_tool to manipulate, examine and tune a filesystem 42 gfs2_tool to manipulate, examine and tune a filesystem
41 gfs2_quota to examine and change quota values in a filesystem 43 gfs2_quota to examine and change quota values in a filesystem
44 gfs2_convert to convert a gfs filesystem to gfs2 in-place
42 mount.gfs2 to help mount(8) mount a filesystem 45 mount.gfs2 to help mount(8) mount a filesystem
43 mkfs.gfs2 to make a filesystem 46 mkfs.gfs2 to make a filesystem
diff --git a/Documentation/futex-requeue-pi.txt b/Documentation/futex-requeue-pi.txt
new file mode 100644
index 00000000000..9dc1ff4fd53
--- /dev/null
+++ b/Documentation/futex-requeue-pi.txt
@@ -0,0 +1,131 @@
1Futex Requeue PI
2----------------
3
4Requeueing of tasks from a non-PI futex to a PI futex requires
5special handling in order to ensure the underlying rt_mutex is never
6left without an owner if it has waiters; doing so would break the PI
7boosting logic [see rt-mutex-desgin.txt] For the purposes of
8brevity, this action will be referred to as "requeue_pi" throughout
9this document. Priority inheritance is abbreviated throughout as
10"PI".
11
12Motivation
13----------
14
15Without requeue_pi, the glibc implementation of
16pthread_cond_broadcast() must resort to waking all the tasks waiting
17on a pthread_condvar and letting them try to sort out which task
18gets to run first in classic thundering-herd formation. An ideal
19implementation would wake the highest-priority waiter, and leave the
20rest to the natural wakeup inherent in unlocking the mutex
21associated with the condvar.
22
23Consider the simplified glibc calls:
24
25/* caller must lock mutex */
26pthread_cond_wait(cond, mutex)
27{
28 lock(cond->__data.__lock);
29 unlock(mutex);
30 do {
31 unlock(cond->__data.__lock);
32 futex_wait(cond->__data.__futex);
33 lock(cond->__data.__lock);
34 } while(...)
35 unlock(cond->__data.__lock);
36 lock(mutex);
37}
38
39pthread_cond_broadcast(cond)
40{
41 lock(cond->__data.__lock);
42 unlock(cond->__data.__lock);
43 futex_requeue(cond->data.__futex, cond->mutex);
44}
45
46Once pthread_cond_broadcast() requeues the tasks, the cond->mutex
47has waiters. Note that pthread_cond_wait() attempts to lock the
48mutex only after it has returned to user space. This will leave the
49underlying rt_mutex with waiters, and no owner, breaking the
50previously mentioned PI-boosting algorithms.
51
52In order to support PI-aware pthread_condvar's, the kernel needs to
53be able to requeue tasks to PI futexes. This support implies that
54upon a successful futex_wait system call, the caller would return to
55user space already holding the PI futex. The glibc implementation
56would be modified as follows:
57
58
59/* caller must lock mutex */
60pthread_cond_wait_pi(cond, mutex)
61{
62 lock(cond->__data.__lock);
63 unlock(mutex);
64 do {
65 unlock(cond->__data.__lock);
66 futex_wait_requeue_pi(cond->__data.__futex);
67 lock(cond->__data.__lock);
68 } while(...)
69 unlock(cond->__data.__lock);
70 /* the kernel acquired the the mutex for us */
71}
72
73pthread_cond_broadcast_pi(cond)
74{
75 lock(cond->__data.__lock);
76 unlock(cond->__data.__lock);
77 futex_requeue_pi(cond->data.__futex, cond->mutex);
78}
79
80The actual glibc implementation will likely test for PI and make the
81necessary changes inside the existing calls rather than creating new
82calls for the PI cases. Similar changes are needed for
83pthread_cond_timedwait() and pthread_cond_signal().
84
85Implementation
86--------------
87
88In order to ensure the rt_mutex has an owner if it has waiters, it
89is necessary for both the requeue code, as well as the waiting code,
90to be able to acquire the rt_mutex before returning to user space.
91The requeue code cannot simply wake the waiter and leave it to
92acquire the rt_mutex as it would open a race window between the
93requeue call returning to user space and the waiter waking and
94starting to run. This is especially true in the uncontended case.
95
96The solution involves two new rt_mutex helper routines,
97rt_mutex_start_proxy_lock() and rt_mutex_finish_proxy_lock(), which
98allow the requeue code to acquire an uncontended rt_mutex on behalf
99of the waiter and to enqueue the waiter on a contended rt_mutex.
100Two new system calls provide the kernel<->user interface to
101requeue_pi: FUTEX_WAIT_REQUEUE_PI and FUTEX_REQUEUE_CMP_PI.
102
103FUTEX_WAIT_REQUEUE_PI is called by the waiter (pthread_cond_wait()
104and pthread_cond_timedwait()) to block on the initial futex and wait
105to be requeued to a PI-aware futex. The implementation is the
106result of a high-speed collision between futex_wait() and
107futex_lock_pi(), with some extra logic to check for the additional
108wake-up scenarios.
109
110FUTEX_REQUEUE_CMP_PI is called by the waker
111(pthread_cond_broadcast() and pthread_cond_signal()) to requeue and
112possibly wake the waiting tasks. Internally, this system call is
113still handled by futex_requeue (by passing requeue_pi=1). Before
114requeueing, futex_requeue() attempts to acquire the requeue target
115PI futex on behalf of the top waiter. If it can, this waiter is
116woken. futex_requeue() then proceeds to requeue the remaining
117nr_wake+nr_requeue tasks to the PI futex, calling
118rt_mutex_start_proxy_lock() prior to each requeue to prepare the
119task as a waiter on the underlying rt_mutex. It is possible that
120the lock can be acquired at this stage as well, if so, the next
121waiter is woken to finish the acquisition of the lock.
122
123FUTEX_REQUEUE_PI accepts nr_wake and nr_requeue as arguments, but
124their sum is all that really matters. futex_requeue() will wake or
125requeue up to nr_wake + nr_requeue tasks. It will wake only as many
126tasks as it can acquire the lock for, which in the majority of cases
127should be 0 as good programming practice dictates that the caller of
128either pthread_cond_broadcast() or pthread_cond_signal() acquire the
129mutex prior to making the call. FUTEX_REQUEUE_PI requires that
130nr_wake=1. nr_requeue should be INT_MAX for broadcast and 0 for
131signal.
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 11648c13a72..7bcdebffdab 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -56,7 +56,6 @@ parameter is applicable:
56 ISAPNP ISA PnP code is enabled. 56 ISAPNP ISA PnP code is enabled.
57 ISDN Appropriate ISDN support is enabled. 57 ISDN Appropriate ISDN support is enabled.
58 JOY Appropriate joystick support is enabled. 58 JOY Appropriate joystick support is enabled.
59 KMEMTRACE kmemtrace is enabled.
60 LIBATA Libata driver is enabled 59 LIBATA Libata driver is enabled
61 LP Printer support is enabled. 60 LP Printer support is enabled.
62 LOOP Loopback device support is enabled. 61 LOOP Loopback device support is enabled.
@@ -329,11 +328,6 @@ and is between 256 and 4096 characters. It is defined in the file
329 flushed before they will be reused, which 328 flushed before they will be reused, which
330 is a lot of faster 329 is a lot of faster
331 330
332 amd_iommu_size= [HW,X86-64]
333 Define the size of the aperture for the AMD IOMMU
334 driver. Possible values are:
335 '32M', '64M' (default), '128M', '256M', '512M', '1G'
336
337 amijoy.map= [HW,JOY] Amiga joystick support 331 amijoy.map= [HW,JOY] Amiga joystick support
338 Map of devices attached to JOY0DAT and JOY1DAT 332 Map of devices attached to JOY0DAT and JOY1DAT
339 Format: <a>,<b> 333 Format: <a>,<b>
@@ -646,6 +640,13 @@ and is between 256 and 4096 characters. It is defined in the file
646 DMA-API debugging code disables itself because the 640 DMA-API debugging code disables itself because the
647 architectural default is too low. 641 architectural default is too low.
648 642
643 dma_debug_driver=<driver_name>
644 With this option the DMA-API debugging driver
645 filter feature can be enabled at boot time. Just
646 pass the driver to filter for as the parameter.
647 The filter can be disabled or changed to another
648 driver later using sysfs.
649
649 dscc4.setup= [NET] 650 dscc4.setup= [NET]
650 651
651 dtc3181e= [HW,SCSI] 652 dtc3181e= [HW,SCSI]
@@ -752,12 +753,25 @@ and is between 256 and 4096 characters. It is defined in the file
752 ia64_pal_cache_flush instead of SAL_CACHE_FLUSH. 753 ia64_pal_cache_flush instead of SAL_CACHE_FLUSH.
753 754
754 ftrace=[tracer] 755 ftrace=[tracer]
755 [ftrace] will set and start the specified tracer 756 [FTRACE] will set and start the specified tracer
756 as early as possible in order to facilitate early 757 as early as possible in order to facilitate early
757 boot debugging. 758 boot debugging.
758 759
759 ftrace_dump_on_oops 760 ftrace_dump_on_oops
760 [ftrace] will dump the trace buffers on oops. 761 [FTRACE] will dump the trace buffers on oops.
762
763 ftrace_filter=[function-list]
764 [FTRACE] Limit the functions traced by the function
765 tracer at boot up. function-list is a comma separated
766 list of functions. This list can be changed at run
767 time by the set_ftrace_filter file in the debugfs
768 tracing directory.
769
770 ftrace_notrace=[function-list]
771 [FTRACE] Do not trace the functions specified in
772 function-list. This list can be changed at run time
773 by the set_ftrace_notrace file in the debugfs
774 tracing directory.
761 775
762 gamecon.map[2|3]= 776 gamecon.map[2|3]=
763 [HW,JOY] Multisystem joystick and NES/SNES/PSX pad 777 [HW,JOY] Multisystem joystick and NES/SNES/PSX pad
@@ -914,6 +928,12 @@ and is between 256 and 4096 characters. It is defined in the file
914 Formt: { "sha1" | "md5" } 928 Formt: { "sha1" | "md5" }
915 default: "sha1" 929 default: "sha1"
916 930
931 ima_tcb [IMA]
932 Load a policy which meets the needs of the Trusted
933 Computing Base. This means IMA will measure all
934 programs exec'd, files mmap'd for exec, and all files
935 opened for read by uid=0.
936
917 in2000= [HW,SCSI] 937 in2000= [HW,SCSI]
918 See header of drivers/scsi/in2000.c. 938 See header of drivers/scsi/in2000.c.
919 939
@@ -1054,15 +1074,6 @@ and is between 256 and 4096 characters. It is defined in the file
1054 use the HighMem zone if it exists, and the Normal 1074 use the HighMem zone if it exists, and the Normal
1055 zone if it does not. 1075 zone if it does not.
1056 1076
1057 kmemtrace.enable= [KNL,KMEMTRACE] Format: { yes | no }
1058 Controls whether kmemtrace is enabled
1059 at boot-time.
1060
1061 kmemtrace.subbufs=n [KNL,KMEMTRACE] Overrides the number of
1062 subbufs kmemtrace's relay channel has. Set this
1063 higher than default (KMEMTRACE_N_SUBBUFS in code) if
1064 you experience buffer overruns.
1065
1066 kgdboc= [HW] kgdb over consoles. 1077 kgdboc= [HW] kgdb over consoles.
1067 Requires a tty driver that supports console polling. 1078 Requires a tty driver that supports console polling.
1068 (only serial suported for now) 1079 (only serial suported for now)
@@ -1072,6 +1083,10 @@ and is between 256 and 4096 characters. It is defined in the file
1072 Configure the RouterBoard 532 series on-chip 1083 Configure the RouterBoard 532 series on-chip
1073 Ethernet adapter MAC address. 1084 Ethernet adapter MAC address.
1074 1085
1086 kmemleak= [KNL] Boot-time kmemleak enable/disable
1087 Valid arguments: on, off
1088 Default: on
1089
1075 kstack=N [X86] Print N words from the kernel stack 1090 kstack=N [X86] Print N words from the kernel stack
1076 in oops dumps. 1091 in oops dumps.
1077 1092
@@ -1663,6 +1678,14 @@ and is between 256 and 4096 characters. It is defined in the file
1663 oprofile.timer= [HW] 1678 oprofile.timer= [HW]
1664 Use timer interrupt instead of performance counters 1679 Use timer interrupt instead of performance counters
1665 1680
1681 oprofile.cpu_type= Force an oprofile cpu type
1682 This might be useful if you have an older oprofile
1683 userland or if you want common events.
1684 Format: { archperfmon }
1685 archperfmon: [X86] Force use of architectural
1686 perfmon on Intel CPUs instead of the
1687 CPU specific event set.
1688
1666 osst= [HW,SCSI] SCSI Tape Driver 1689 osst= [HW,SCSI] SCSI Tape Driver
1667 Format: <buffer_size>,<write_threshold> 1690 Format: <buffer_size>,<write_threshold>
1668 See also Documentation/scsi/st.txt. 1691 See also Documentation/scsi/st.txt.
diff --git a/Documentation/kmemleak.txt b/Documentation/kmemleak.txt
new file mode 100644
index 00000000000..0112da3b9ab
--- /dev/null
+++ b/Documentation/kmemleak.txt
@@ -0,0 +1,142 @@
1Kernel Memory Leak Detector
2===========================
3
4Introduction
5------------
6
7Kmemleak provides a way of detecting possible kernel memory leaks in a
8way similar to a tracing garbage collector
9(http://en.wikipedia.org/wiki/Garbage_collection_%28computer_science%29#Tracing_garbage_collectors),
10with the difference that the orphan objects are not freed but only
11reported via /sys/kernel/debug/kmemleak. A similar method is used by the
12Valgrind tool (memcheck --leak-check) to detect the memory leaks in
13user-space applications.
14
15Usage
16-----
17
18CONFIG_DEBUG_KMEMLEAK in "Kernel hacking" has to be enabled. A kernel
19thread scans the memory every 10 minutes (by default) and prints any new
20unreferenced objects found. To trigger an intermediate scan and display
21all the possible memory leaks:
22
23 # mount -t debugfs nodev /sys/kernel/debug/
24 # cat /sys/kernel/debug/kmemleak
25
26Note that the orphan objects are listed in the order they were allocated
27and one object at the beginning of the list may cause other subsequent
28objects to be reported as orphan.
29
30Memory scanning parameters can be modified at run-time by writing to the
31/sys/kernel/debug/kmemleak file. The following parameters are supported:
32
33 off - disable kmemleak (irreversible)
34 stack=on - enable the task stacks scanning
35 stack=off - disable the tasks stacks scanning
36 scan=on - start the automatic memory scanning thread
37 scan=off - stop the automatic memory scanning thread
38 scan=<secs> - set the automatic memory scanning period in seconds (0
39 to disable it)
40
41Kmemleak can also be disabled at boot-time by passing "kmemleak=off" on
42the kernel command line.
43
44Basic Algorithm
45---------------
46
47The memory allocations via kmalloc, vmalloc, kmem_cache_alloc and
48friends are traced and the pointers, together with additional
49information like size and stack trace, are stored in a prio search tree.
50The corresponding freeing function calls are tracked and the pointers
51removed from the kmemleak data structures.
52
53An allocated block of memory is considered orphan if no pointer to its
54start address or to any location inside the block can be found by
55scanning the memory (including saved registers). This means that there
56might be no way for the kernel to pass the address of the allocated
57block to a freeing function and therefore the block is considered a
58memory leak.
59
60The scanning algorithm steps:
61
62 1. mark all objects as white (remaining white objects will later be
63 considered orphan)
64 2. scan the memory starting with the data section and stacks, checking
65 the values against the addresses stored in the prio search tree. If
66 a pointer to a white object is found, the object is added to the
67 gray list
68 3. scan the gray objects for matching addresses (some white objects
69 can become gray and added at the end of the gray list) until the
70 gray set is finished
71 4. the remaining white objects are considered orphan and reported via
72 /sys/kernel/debug/kmemleak
73
74Some allocated memory blocks have pointers stored in the kernel's
75internal data structures and they cannot be detected as orphans. To
76avoid this, kmemleak can also store the number of values pointing to an
77address inside the block address range that need to be found so that the
78block is not considered a leak. One example is __vmalloc().
79
80Kmemleak API
81------------
82
83See the include/linux/kmemleak.h header for the functions prototype.
84
85kmemleak_init - initialize kmemleak
86kmemleak_alloc - notify of a memory block allocation
87kmemleak_free - notify of a memory block freeing
88kmemleak_not_leak - mark an object as not a leak
89kmemleak_ignore - do not scan or report an object as leak
90kmemleak_scan_area - add scan areas inside a memory block
91kmemleak_no_scan - do not scan a memory block
92kmemleak_erase - erase an old value in a pointer variable
93kmemleak_alloc_recursive - as kmemleak_alloc but checks the recursiveness
94kmemleak_free_recursive - as kmemleak_free but checks the recursiveness
95
96Dealing with false positives/negatives
97--------------------------------------
98
99The false negatives are real memory leaks (orphan objects) but not
100reported by kmemleak because values found during the memory scanning
101point to such objects. To reduce the number of false negatives, kmemleak
102provides the kmemleak_ignore, kmemleak_scan_area, kmemleak_no_scan and
103kmemleak_erase functions (see above). The task stacks also increase the
104amount of false negatives and their scanning is not enabled by default.
105
106The false positives are objects wrongly reported as being memory leaks
107(orphan). For objects known not to be leaks, kmemleak provides the
108kmemleak_not_leak function. The kmemleak_ignore could also be used if
109the memory block is known not to contain other pointers and it will no
110longer be scanned.
111
112Some of the reported leaks are only transient, especially on SMP
113systems, because of pointers temporarily stored in CPU registers or
114stacks. Kmemleak defines MSECS_MIN_AGE (defaulting to 1000) representing
115the minimum age of an object to be reported as a memory leak.
116
117Limitations and Drawbacks
118-------------------------
119
120The main drawback is the reduced performance of memory allocation and
121freeing. To avoid other penalties, the memory scanning is only performed
122when the /sys/kernel/debug/kmemleak file is read. Anyway, this tool is
123intended for debugging purposes where the performance might not be the
124most important requirement.
125
126To keep the algorithm simple, kmemleak scans for values pointing to any
127address inside a block's address range. This may lead to an increased
128number of false negatives. However, it is likely that a real memory leak
129will eventually become visible.
130
131Another source of false negatives is the data stored in non-pointer
132values. In a future version, kmemleak could only scan the pointer
133members in the allocated structures. This feature would solve many of
134the false negative cases described above.
135
136The tool can report false positives. These are cases where an allocated
137block doesn't need to be freed (some cases in the init_call functions),
138the pointer is calculated by other methods than the usual container_of
139macro or the pointer is stored in a location not scanned by kmemleak.
140
141Page allocations and ioremap are not tracked. Only the ARM and x86
142architectures are currently supported.
diff --git a/Documentation/memory-barriers.txt b/Documentation/memory-barriers.txt
index f5b7127f54a..7f5809eddee 100644
--- a/Documentation/memory-barriers.txt
+++ b/Documentation/memory-barriers.txt
@@ -31,6 +31,7 @@ Contents:
31 31
32 - Locking functions. 32 - Locking functions.
33 - Interrupt disabling functions. 33 - Interrupt disabling functions.
34 - Sleep and wake-up functions.
34 - Miscellaneous functions. 35 - Miscellaneous functions.
35 36
36 (*) Inter-CPU locking barrier effects. 37 (*) Inter-CPU locking barrier effects.
@@ -1217,6 +1218,132 @@ barriers are required in such a situation, they must be provided from some
1217other means. 1218other means.
1218 1219
1219 1220
1221SLEEP AND WAKE-UP FUNCTIONS
1222---------------------------
1223
1224Sleeping and waking on an event flagged in global data can be viewed as an
1225interaction between two pieces of data: the task state of the task waiting for
1226the event and the global data used to indicate the event. To make sure that
1227these appear to happen in the right order, the primitives to begin the process
1228of going to sleep, and the primitives to initiate a wake up imply certain
1229barriers.
1230
1231Firstly, the sleeper normally follows something like this sequence of events:
1232
1233 for (;;) {
1234 set_current_state(TASK_UNINTERRUPTIBLE);
1235 if (event_indicated)
1236 break;
1237 schedule();
1238 }
1239
1240A general memory barrier is interpolated automatically by set_current_state()
1241after it has altered the task state:
1242
1243 CPU 1
1244 ===============================
1245 set_current_state();
1246 set_mb();
1247 STORE current->state
1248 <general barrier>
1249 LOAD event_indicated
1250
1251set_current_state() may be wrapped by:
1252
1253 prepare_to_wait();
1254 prepare_to_wait_exclusive();
1255
1256which therefore also imply a general memory barrier after setting the state.
1257The whole sequence above is available in various canned forms, all of which
1258interpolate the memory barrier in the right place:
1259
1260 wait_event();
1261 wait_event_interruptible();
1262 wait_event_interruptible_exclusive();
1263 wait_event_interruptible_timeout();
1264 wait_event_killable();
1265 wait_event_timeout();
1266 wait_on_bit();
1267 wait_on_bit_lock();
1268
1269
1270Secondly, code that performs a wake up normally follows something like this:
1271
1272 event_indicated = 1;
1273 wake_up(&event_wait_queue);
1274
1275or:
1276
1277 event_indicated = 1;
1278 wake_up_process(event_daemon);
1279
1280A write memory barrier is implied by wake_up() and co. if and only if they wake
1281something up. The barrier occurs before the task state is cleared, and so sits
1282between the STORE to indicate the event and the STORE to set TASK_RUNNING:
1283
1284 CPU 1 CPU 2
1285 =============================== ===============================
1286 set_current_state(); STORE event_indicated
1287 set_mb(); wake_up();
1288 STORE current->state <write barrier>
1289 <general barrier> STORE current->state
1290 LOAD event_indicated
1291
1292The available waker functions include:
1293
1294 complete();
1295 wake_up();
1296 wake_up_all();
1297 wake_up_bit();
1298 wake_up_interruptible();
1299 wake_up_interruptible_all();
1300 wake_up_interruptible_nr();
1301 wake_up_interruptible_poll();
1302 wake_up_interruptible_sync();
1303 wake_up_interruptible_sync_poll();
1304 wake_up_locked();
1305 wake_up_locked_poll();
1306 wake_up_nr();
1307 wake_up_poll();
1308 wake_up_process();
1309
1310
1311[!] Note that the memory barriers implied by the sleeper and the waker do _not_
1312order multiple stores before the wake-up with respect to loads of those stored
1313values after the sleeper has called set_current_state(). For instance, if the
1314sleeper does:
1315
1316 set_current_state(TASK_INTERRUPTIBLE);
1317 if (event_indicated)
1318 break;
1319 __set_current_state(TASK_RUNNING);
1320 do_something(my_data);
1321
1322and the waker does:
1323
1324 my_data = value;
1325 event_indicated = 1;
1326 wake_up(&event_wait_queue);
1327
1328there's no guarantee that the change to event_indicated will be perceived by
1329the sleeper as coming after the change to my_data. In such a circumstance, the
1330code on both sides must interpolate its own memory barriers between the
1331separate data accesses. Thus the above sleeper ought to do:
1332
1333 set_current_state(TASK_INTERRUPTIBLE);
1334 if (event_indicated) {
1335 smp_rmb();
1336 do_something(my_data);
1337 }
1338
1339and the waker should do:
1340
1341 my_data = value;
1342 smp_wmb();
1343 event_indicated = 1;
1344 wake_up(&event_wait_queue);
1345
1346
1220MISCELLANEOUS FUNCTIONS 1347MISCELLANEOUS FUNCTIONS
1221----------------------- 1348-----------------------
1222 1349
@@ -1366,7 +1493,7 @@ WHERE ARE MEMORY BARRIERS NEEDED?
1366 1493
1367Under normal operation, memory operation reordering is generally not going to 1494Under normal operation, memory operation reordering is generally not going to
1368be a problem as a single-threaded linear piece of code will still appear to 1495be a problem as a single-threaded linear piece of code will still appear to
1369work correctly, even if it's in an SMP kernel. There are, however, three 1496work correctly, even if it's in an SMP kernel. There are, however, four
1370circumstances in which reordering definitely _could_ be a problem: 1497circumstances in which reordering definitely _could_ be a problem:
1371 1498
1372 (*) Interprocessor interaction. 1499 (*) Interprocessor interaction.
diff --git a/Documentation/scheduler/sched-rt-group.txt b/Documentation/scheduler/sched-rt-group.txt
index 5ba4d3fc625..1df7f9cdab0 100644
--- a/Documentation/scheduler/sched-rt-group.txt
+++ b/Documentation/scheduler/sched-rt-group.txt
@@ -4,6 +4,7 @@
4CONTENTS 4CONTENTS
5======== 5========
6 6
70. WARNING
71. Overview 81. Overview
8 1.1 The problem 9 1.1 The problem
9 1.2 The solution 10 1.2 The solution
@@ -14,6 +15,23 @@ CONTENTS
143. Future plans 153. Future plans
15 16
16 17
180. WARNING
19==========
20
21 Fiddling with these settings can result in an unstable system, the knobs are
22 root only and assumes root knows what he is doing.
23
24Most notable:
25
26 * very small values in sched_rt_period_us can result in an unstable
27 system when the period is smaller than either the available hrtimer
28 resolution, or the time it takes to handle the budget refresh itself.
29
30 * very small values in sched_rt_runtime_us can result in an unstable
31 system when the runtime is so small the system has difficulty making
32 forward progress (NOTE: the migration thread and kstopmachine both
33 are real-time processes).
34
171. Overview 351. Overview
18=========== 36===========
19 37
@@ -169,7 +187,7 @@ get their allocated time.
169 187
170Implementing SCHED_EDF might take a while to complete. Priority Inheritance is 188Implementing SCHED_EDF might take a while to complete. Priority Inheritance is
171the biggest challenge as the current linux PI infrastructure is geared towards 189the biggest challenge as the current linux PI infrastructure is geared towards
172the limited static priority levels 0-139. With deadline scheduling you need to 190the limited static priority levels 0-99. With deadline scheduling you need to
173do deadline inheritance (since priority is inversely proportional to the 191do deadline inheritance (since priority is inversely proportional to the
174deadline delta (deadline - now). 192deadline delta (deadline - now).
175 193
diff --git a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt
index f11ca7979fa..322a00bb99d 100644
--- a/Documentation/sysctl/kernel.txt
+++ b/Documentation/sysctl/kernel.txt
@@ -32,6 +32,7 @@ show up in /proc/sys/kernel:
32- kstack_depth_to_print [ X86 only ] 32- kstack_depth_to_print [ X86 only ]
33- l2cr [ PPC only ] 33- l2cr [ PPC only ]
34- modprobe ==> Documentation/debugging-modules.txt 34- modprobe ==> Documentation/debugging-modules.txt
35- modules_disabled
35- msgmax 36- msgmax
36- msgmnb 37- msgmnb
37- msgmni 38- msgmni
@@ -184,6 +185,16 @@ kernel stack.
184 185
185============================================================== 186==============================================================
186 187
188modules_disabled:
189
190A toggle value indicating if modules are allowed to be loaded
191in an otherwise modular kernel. This toggle defaults to off
192(0), but can be set true (1). Once true, modules can be
193neither loaded nor unloaded, and the toggle cannot be set back
194to false.
195
196==============================================================
197
187osrelease, ostype & version: 198osrelease, ostype & version:
188 199
189# cat osrelease 200# cat osrelease
diff --git a/Documentation/trace/events.txt b/Documentation/trace/events.txt
new file mode 100644
index 00000000000..f157d7594ea
--- /dev/null
+++ b/Documentation/trace/events.txt
@@ -0,0 +1,90 @@
1 Event Tracing
2
3 Documentation written by Theodore Ts'o
4 Updated by Li Zefan
5
61. Introduction
7===============
8
9Tracepoints (see Documentation/trace/tracepoints.txt) can be used
10without creating custom kernel modules to register probe functions
11using the event tracing infrastructure.
12
13Not all tracepoints can be traced using the event tracing system;
14the kernel developer must provide code snippets which define how the
15tracing information is saved into the tracing buffer, and how the
16tracing information should be printed.
17
182. Using Event Tracing
19======================
20
212.1 Via the 'set_event' interface
22---------------------------------
23
24The events which are available for tracing can be found in the file
25/debug/tracing/available_events.
26
27To enable a particular event, such as 'sched_wakeup', simply echo it
28to /debug/tracing/set_event. For example:
29
30 # echo sched_wakeup >> /debug/tracing/set_event
31
32[ Note: '>>' is necessary, otherwise it will firstly disable
33 all the events. ]
34
35To disable an event, echo the event name to the set_event file prefixed
36with an exclamation point:
37
38 # echo '!sched_wakeup' >> /debug/tracing/set_event
39
40To disable all events, echo an empty line to the set_event file:
41
42 # echo > /debug/tracing/set_event
43
44To enable all events, echo '*:*' or '*:' to the set_event file:
45
46 # echo *:* > /debug/tracing/set_event
47
48The events are organized into subsystems, such as ext4, irq, sched,
49etc., and a full event name looks like this: <subsystem>:<event>. The
50subsystem name is optional, but it is displayed in the available_events
51file. All of the events in a subsystem can be specified via the syntax
52"<subsystem>:*"; for example, to enable all irq events, you can use the
53command:
54
55 # echo 'irq:*' > /debug/tracing/set_event
56
572.2 Via the 'enable' toggle
58---------------------------
59
60The events available are also listed in /debug/tracing/events/ hierarchy
61of directories.
62
63To enable event 'sched_wakeup':
64
65 # echo 1 > /debug/tracing/events/sched/sched_wakeup/enable
66
67To disable it:
68
69 # echo 0 > /debug/tracing/events/sched/sched_wakeup/enable
70
71To enable all events in sched subsystem:
72
73 # echo 1 > /debug/tracing/events/sched/enable
74
75To eanble all events:
76
77 # echo 1 > /debug/tracing/events/enable
78
79When reading one of these enable files, there are four results:
80
81 0 - all events this file affects are disabled
82 1 - all events this file affects are enabled
83 X - there is a mixture of events enabled and disabled
84 ? - this file does not affect any event
85
863. Defining an event-enabled tracepoint
87=======================================
88
89See The example provided in samples/trace_events
90
diff --git a/Documentation/trace/ftrace.txt b/Documentation/trace/ftrace.txt
index fd9a3e69381..2a82d860294 100644
--- a/Documentation/trace/ftrace.txt
+++ b/Documentation/trace/ftrace.txt
@@ -179,7 +179,7 @@ Here is the list of current tracers that may be configured.
179 179
180 Function call tracer to trace all kernel functions. 180 Function call tracer to trace all kernel functions.
181 181
182 "function_graph_tracer" 182 "function_graph"
183 183
184 Similar to the function tracer except that the 184 Similar to the function tracer except that the
185 function tracer probes the functions on their entry 185 function tracer probes the functions on their entry
@@ -518,9 +518,18 @@ priority with zero (0) being the highest priority and the nice
518values starting at 100 (nice -20). Below is a quick chart to map 518values starting at 100 (nice -20). Below is a quick chart to map
519the kernel priority to user land priorities. 519the kernel priority to user land priorities.
520 520
521 Kernel priority: 0 to 99 ==> user RT priority 99 to 0 521 Kernel Space User Space
522 Kernel priority: 100 to 139 ==> user nice -20 to 19 522 ===============================================================
523 Kernel priority: 140 ==> idle task priority 523 0(high) to 98(low) user RT priority 99(high) to 1(low)
524 with SCHED_RR or SCHED_FIFO
525 ---------------------------------------------------------------
526 99 sched_priority is not used in scheduling
527 decisions(it must be specified as 0)
528 ---------------------------------------------------------------
529 100(high) to 139(low) user nice -20(high) to 19(low)
530 ---------------------------------------------------------------
531 140 idle task priority
532 ---------------------------------------------------------------
524 533
525The task states are: 534The task states are:
526 535
diff --git a/Documentation/trace/power.txt b/Documentation/trace/power.txt
new file mode 100644
index 00000000000..cd805e16dc2
--- /dev/null
+++ b/Documentation/trace/power.txt
@@ -0,0 +1,17 @@
1The power tracer collects detailed information about C-state and P-state
2transitions, instead of just looking at the high-level "average"
3information.
4
5There is a helper script found in scrips/tracing/power.pl in the kernel
6sources which can be used to parse this information and create a
7Scalable Vector Graphics (SVG) picture from the trace data.
8
9To use this tracer:
10
11 echo 0 > /sys/kernel/debug/tracing/tracing_enabled
12 echo power > /sys/kernel/debug/tracing/current_tracer
13 echo 1 > /sys/kernel/debug/tracing/tracing_enabled
14 sleep 1
15 echo 0 > /sys/kernel/debug/tracing/tracing_enabled
16 cat /sys/kernel/debug/tracing/trace | \
17 perl scripts/tracing/power.pl > out.sv
diff --git a/Documentation/x86/boot.txt b/Documentation/x86/boot.txt
index e0203662f9e..8da3a795083 100644
--- a/Documentation/x86/boot.txt
+++ b/Documentation/x86/boot.txt
@@ -50,6 +50,10 @@ Protocol 2.08: (Kernel 2.6.26) Added crc32 checksum and ELF format
50Protocol 2.09: (Kernel 2.6.26) Added a field of 64-bit physical 50Protocol 2.09: (Kernel 2.6.26) Added a field of 64-bit physical
51 pointer to single linked list of struct setup_data. 51 pointer to single linked list of struct setup_data.
52 52
53Protocol 2.10: (Kernel 2.6.31) Added a protocol for relaxed alignment
54 beyond the kernel_alignment added, new init_size and
55 pref_address fields. Added extended boot loader IDs.
56
53**** MEMORY LAYOUT 57**** MEMORY LAYOUT
54 58
55The traditional memory map for the kernel loader, used for Image or 59The traditional memory map for the kernel loader, used for Image or
@@ -168,12 +172,13 @@ Offset Proto Name Meaning
168021C/4 2.00+ ramdisk_size initrd size (set by boot loader) 172021C/4 2.00+ ramdisk_size initrd size (set by boot loader)
1690220/4 2.00+ bootsect_kludge DO NOT USE - for bootsect.S use only 1730220/4 2.00+ bootsect_kludge DO NOT USE - for bootsect.S use only
1700224/2 2.01+ heap_end_ptr Free memory after setup end 1740224/2 2.01+ heap_end_ptr Free memory after setup end
1710226/2 N/A pad1 Unused 1750226/1 2.02+(3 ext_loader_ver Extended boot loader version
1760227/1 2.02+(3 ext_loader_type Extended boot loader ID
1720228/4 2.02+ cmd_line_ptr 32-bit pointer to the kernel command line 1770228/4 2.02+ cmd_line_ptr 32-bit pointer to the kernel command line
173022C/4 2.03+ ramdisk_max Highest legal initrd address 178022C/4 2.03+ ramdisk_max Highest legal initrd address
1740230/4 2.05+ kernel_alignment Physical addr alignment required for kernel 1790230/4 2.05+ kernel_alignment Physical addr alignment required for kernel
1750234/1 2.05+ relocatable_kernel Whether kernel is relocatable or not 1800234/1 2.05+ relocatable_kernel Whether kernel is relocatable or not
1760235/1 N/A pad2 Unused 1810235/1 2.10+ min_alignment Minimum alignment, as a power of two
1770236/2 N/A pad3 Unused 1820236/2 N/A pad3 Unused
1780238/4 2.06+ cmdline_size Maximum size of the kernel command line 1830238/4 2.06+ cmdline_size Maximum size of the kernel command line
179023C/4 2.07+ hardware_subarch Hardware subarchitecture 184023C/4 2.07+ hardware_subarch Hardware subarchitecture
@@ -182,6 +187,8 @@ Offset Proto Name Meaning
182024C/4 2.08+ payload_length Length of kernel payload 187024C/4 2.08+ payload_length Length of kernel payload
1830250/8 2.09+ setup_data 64-bit physical pointer to linked list 1880250/8 2.09+ setup_data 64-bit physical pointer to linked list
184 of struct setup_data 189 of struct setup_data
1900258/8 2.10+ pref_address Preferred loading address
1910260/4 2.10+ init_size Linear memory required during initialization
185 192
186(1) For backwards compatibility, if the setup_sects field contains 0, the 193(1) For backwards compatibility, if the setup_sects field contains 0, the
187 real value is 4. 194 real value is 4.
@@ -190,6 +197,8 @@ Offset Proto Name Meaning
190 field are unusable, which means the size of a bzImage kernel 197 field are unusable, which means the size of a bzImage kernel
191 cannot be determined. 198 cannot be determined.
192 199
200(3) Ignored, but safe to set, for boot protocols 2.02-2.09.
201
193If the "HdrS" (0x53726448) magic number is not found at offset 0x202, 202If the "HdrS" (0x53726448) magic number is not found at offset 0x202,
194the boot protocol version is "old". Loading an old kernel, the 203the boot protocol version is "old". Loading an old kernel, the
195following parameters should be assumed: 204following parameters should be assumed:
@@ -343,18 +352,32 @@ Protocol: 2.00+
343 0xTV here, where T is an identifier for the boot loader and V is 352 0xTV here, where T is an identifier for the boot loader and V is
344 a version number. Otherwise, enter 0xFF here. 353 a version number. Otherwise, enter 0xFF here.
345 354
355 For boot loader IDs above T = 0xD, write T = 0xE to this field and
356 write the extended ID minus 0x10 to the ext_loader_type field.
357 Similarly, the ext_loader_ver field can be used to provide more than
358 four bits for the bootloader version.
359
360 For example, for T = 0x15, V = 0x234, write:
361
362 type_of_loader <- 0xE4
363 ext_loader_type <- 0x05
364 ext_loader_ver <- 0x23
365
346 Assigned boot loader ids: 366 Assigned boot loader ids:
347 0 LILO (0x00 reserved for pre-2.00 bootloader) 367 0 LILO (0x00 reserved for pre-2.00 bootloader)
348 1 Loadlin 368 1 Loadlin
349 2 bootsect-loader (0x20, all other values reserved) 369 2 bootsect-loader (0x20, all other values reserved)
350 3 SYSLINUX 370 3 Syslinux
351 4 EtherBoot 371 4 Etherboot/gPXE
352 5 ELILO 372 5 ELILO
353 7 GRUB 373 7 GRUB
354 8 U-BOOT 374 8 U-Boot
355 9 Xen 375 9 Xen
356 A Gujin 376 A Gujin
357 B Qemu 377 B Qemu
378 C Arcturus Networks uCbootloader
379 E Extended (see ext_loader_type)
380 F Special (0xFF = undefined)
358 381
359 Please contact <hpa@zytor.com> if you need a bootloader ID 382 Please contact <hpa@zytor.com> if you need a bootloader ID
360 value assigned. 383 value assigned.
@@ -453,6 +476,35 @@ Protocol: 2.01+
453 Set this field to the offset (from the beginning of the real-mode 476 Set this field to the offset (from the beginning of the real-mode
454 code) of the end of the setup stack/heap, minus 0x0200. 477 code) of the end of the setup stack/heap, minus 0x0200.
455 478
479Field name: ext_loader_ver
480Type: write (optional)
481Offset/size: 0x226/1
482Protocol: 2.02+
483
484 This field is used as an extension of the version number in the
485 type_of_loader field. The total version number is considered to be
486 (type_of_loader & 0x0f) + (ext_loader_ver << 4).
487
488 The use of this field is boot loader specific. If not written, it
489 is zero.
490
491 Kernels prior to 2.6.31 did not recognize this field, but it is safe
492 to write for protocol version 2.02 or higher.
493
494Field name: ext_loader_type
495Type: write (obligatory if (type_of_loader & 0xf0) == 0xe0)
496Offset/size: 0x227/1
497Protocol: 2.02+
498
499 This field is used as an extension of the type number in
500 type_of_loader field. If the type in type_of_loader is 0xE, then
501 the actual type is (ext_loader_type + 0x10).
502
503 This field is ignored if the type in type_of_loader is not 0xE.
504
505 Kernels prior to 2.6.31 did not recognize this field, but it is safe
506 to write for protocol version 2.02 or higher.
507
456Field name: cmd_line_ptr 508Field name: cmd_line_ptr
457Type: write (obligatory) 509Type: write (obligatory)
458Offset/size: 0x228/4 510Offset/size: 0x228/4
@@ -482,11 +534,19 @@ Protocol: 2.03+
482 0x37FFFFFF, you can start your ramdisk at 0x37FE0000.) 534 0x37FFFFFF, you can start your ramdisk at 0x37FE0000.)
483 535
484Field name: kernel_alignment 536Field name: kernel_alignment
485Type: read (reloc) 537Type: read/modify (reloc)
486Offset/size: 0x230/4 538Offset/size: 0x230/4
487Protocol: 2.05+ 539Protocol: 2.05+ (read), 2.10+ (modify)
540
541 Alignment unit required by the kernel (if relocatable_kernel is
542 true.) A relocatable kernel that is loaded at an alignment
543 incompatible with the value in this field will be realigned during
544 kernel initialization.
488 545
489 Alignment unit required by the kernel (if relocatable_kernel is true.) 546 Starting with protocol version 2.10, this reflects the kernel
547 alignment preferred for optimal performance; it is possible for the
548 loader to modify this field to permit a lesser alignment. See the
549 min_alignment and pref_address field below.
490 550
491Field name: relocatable_kernel 551Field name: relocatable_kernel
492Type: read (reloc) 552Type: read (reloc)
@@ -498,6 +558,22 @@ Protocol: 2.05+
498 After loading, the boot loader must set the code32_start field to 558 After loading, the boot loader must set the code32_start field to
499 point to the loaded code, or to a boot loader hook. 559 point to the loaded code, or to a boot loader hook.
500 560
561Field name: min_alignment
562Type: read (reloc)
563Offset/size: 0x235/1
564Protocol: 2.10+
565
566 This field, if nonzero, indicates as a power of two the minimum
567 alignment required, as opposed to preferred, by the kernel to boot.
568 If a boot loader makes use of this field, it should update the
569 kernel_alignment field with the alignment unit desired; typically:
570
571 kernel_alignment = 1 << min_alignment
572
573 There may be a considerable performance cost with an excessively
574 misaligned kernel. Therefore, a loader should typically try each
575 power-of-two alignment from kernel_alignment down to this alignment.
576
501Field name: cmdline_size 577Field name: cmdline_size
502Type: read 578Type: read
503Offset/size: 0x238/4 579Offset/size: 0x238/4
@@ -582,6 +658,36 @@ Protocol: 2.09+
582 sure to consider the case where the linked list already contains 658 sure to consider the case where the linked list already contains
583 entries. 659 entries.
584 660
661Field name: pref_address
662Type: read (reloc)
663Offset/size: 0x258/8
664Protocol: 2.10+
665
666 This field, if nonzero, represents a preferred load address for the
667 kernel. A relocating bootloader should attempt to load at this
668 address if possible.
669
670 A non-relocatable kernel will unconditionally move itself and to run
671 at this address.
672
673Field name: init_size
674Type: read
675Offset/size: 0x25c/4
676
677 This field indicates the amount of linear contiguous memory starting
678 at the kernel runtime start address that the kernel needs before it
679 is capable of examining its memory map. This is not the same thing
680 as the total amount of memory the kernel needs to boot, but it can
681 be used by a relocating boot loader to help select a safe load
682 address for the kernel.
683
684 The kernel runtime start address is determined by the following algorithm:
685
686 if (relocatable_kernel)
687 runtime_start = align_up(load_address, kernel_alignment)
688 else
689 runtime_start = pref_address
690
585 691
586**** THE IMAGE CHECKSUM 692**** THE IMAGE CHECKSUM
587 693
diff --git a/Documentation/x86/x86_64/boot-options.txt b/Documentation/x86/x86_64/boot-options.txt
index fa2bed07d21..29a6ff8bc7d 100644
--- a/Documentation/x86/x86_64/boot-options.txt
+++ b/Documentation/x86/x86_64/boot-options.txt
@@ -180,11 +180,6 @@ NUMA
180 Otherwise, the remaining system RAM is allocated to an 180 Otherwise, the remaining system RAM is allocated to an
181 additional node. 181 additional node.
182 182
183 numa=hotadd=percent
184 Only allow hotadd memory to preallocate page structures upto
185 percent of already available memory.
186 numa=hotadd=0 will disable hotadd memory.
187
188ACPI 183ACPI
189 184
190 acpi=off Don't enable ACPI 185 acpi=off Don't enable ACPI
diff --git a/Documentation/x86/x86_64/mm.txt b/Documentation/x86/x86_64/mm.txt
index 29b52b14d0b..d6498e3cd71 100644
--- a/Documentation/x86/x86_64/mm.txt
+++ b/Documentation/x86/x86_64/mm.txt
@@ -6,10 +6,11 @@ Virtual memory map with 4 level page tables:
60000000000000000 - 00007fffffffffff (=47 bits) user space, different per mm 60000000000000000 - 00007fffffffffff (=47 bits) user space, different per mm
7hole caused by [48:63] sign extension 7hole caused by [48:63] sign extension
8ffff800000000000 - ffff80ffffffffff (=40 bits) guard hole 8ffff800000000000 - ffff80ffffffffff (=40 bits) guard hole
9ffff880000000000 - ffffc0ffffffffff (=57 TB) direct mapping of all phys. memory 9ffff880000000000 - ffffc7ffffffffff (=64 TB) direct mapping of all phys. memory
10ffffc10000000000 - ffffc1ffffffffff (=40 bits) hole 10ffffc80000000000 - ffffc8ffffffffff (=40 bits) hole
11ffffc20000000000 - ffffe1ffffffffff (=45 bits) vmalloc/ioremap space 11ffffc90000000000 - ffffe8ffffffffff (=45 bits) vmalloc/ioremap space
12ffffe20000000000 - ffffe2ffffffffff (=40 bits) virtual memory map (1TB) 12ffffe90000000000 - ffffe9ffffffffff (=40 bits) hole
13ffffea0000000000 - ffffeaffffffffff (=40 bits) virtual memory map (1TB)
13... unused hole ... 14... unused hole ...
14ffffffff80000000 - ffffffffa0000000 (=512 MB) kernel text mapping, from phys 0 15ffffffff80000000 - ffffffffa0000000 (=512 MB) kernel text mapping, from phys 0
15ffffffffa0000000 - fffffffffff00000 (=1536 MB) module mapping space 16ffffffffa0000000 - fffffffffff00000 (=1536 MB) module mapping space