diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/DocBook/uio-howto.tmpl | 88 | ||||
| -rw-r--r-- | Documentation/cgroups/memcg_test.txt | 24 | ||||
| -rw-r--r-- | Documentation/filesystems/proc.txt | 28 | ||||
| -rw-r--r-- | Documentation/ja_JP/stable_kernel_rules.txt | 15 | ||||
| -rw-r--r-- | Documentation/lguest/Makefile | 2 |
5 files changed, 149 insertions, 8 deletions
diff --git a/Documentation/DocBook/uio-howto.tmpl b/Documentation/DocBook/uio-howto.tmpl index b787e4721c9..52e1b79ce0e 100644 --- a/Documentation/DocBook/uio-howto.tmpl +++ b/Documentation/DocBook/uio-howto.tmpl @@ -42,6 +42,12 @@ GPL version 2. <revhistory> <revision> + <revnumber>0.7</revnumber> + <date>2008-12-23</date> + <authorinitials>hjk</authorinitials> + <revremark>Added generic platform drivers and offset attribute.</revremark> + </revision> + <revision> <revnumber>0.6</revnumber> <date>2008-12-05</date> <authorinitials>hjk</authorinitials> @@ -312,6 +318,16 @@ interested in translating it, please email me pointed to by addr. </para> </listitem> +<listitem> + <para> + <filename>offset</filename>: The offset, in bytes, that has to be + added to the pointer returned by <function>mmap()</function> to get + to the actual device memory. This is important if the device's memory + is not page aligned. Remember that pointers returned by + <function>mmap()</function> are always page aligned, so it is good + style to always add this offset. + </para> +</listitem> </itemizedlist> <para> @@ -594,6 +610,78 @@ framework to set up sysfs files for this region. Simply leave it alone. </para> </sect1> +<sect1 id="using_uio_pdrv"> +<title>Using uio_pdrv for platform devices</title> + <para> + In many cases, UIO drivers for platform devices can be handled in a + generic way. In the same place where you define your + <varname>struct platform_device</varname>, you simply also implement + your interrupt handler and fill your + <varname>struct uio_info</varname>. A pointer to this + <varname>struct uio_info</varname> is then used as + <varname>platform_data</varname> for your platform device. + </para> + <para> + You also need to set up an array of <varname>struct resource</varname> + containing addresses and sizes of your memory mappings. This + information is passed to the driver using the + <varname>.resource</varname> and <varname>.num_resources</varname> + elements of <varname>struct platform_device</varname>. + </para> + <para> + You now have to set the <varname>.name</varname> element of + <varname>struct platform_device</varname> to + <varname>"uio_pdrv"</varname> to use the generic UIO platform device + driver. This driver will fill the <varname>mem[]</varname> array + according to the resources given, and register the device. + </para> + <para> + The advantage of this approach is that you only have to edit a file + you need to edit anyway. You do not have to create an extra driver. + </para> +</sect1> + +<sect1 id="using_uio_pdrv_genirq"> +<title>Using uio_pdrv_genirq for platform devices</title> + <para> + Especially in embedded devices, you frequently find chips where the + irq pin is tied to its own dedicated interrupt line. In such cases, + where you can be really sure the interrupt is not shared, we can take + the concept of <varname>uio_pdrv</varname> one step further and use a + generic interrupt handler. That's what + <varname>uio_pdrv_genirq</varname> does. + </para> + <para> + The setup for this driver is the same as described above for + <varname>uio_pdrv</varname>, except that you do not implement an + interrupt handler. The <varname>.handler</varname> element of + <varname>struct uio_info</varname> must remain + <varname>NULL</varname>. The <varname>.irq_flags</varname> element + must not contain <varname>IRQF_SHARED</varname>. + </para> + <para> + You will set the <varname>.name</varname> element of + <varname>struct platform_device</varname> to + <varname>"uio_pdrv_genirq"</varname> to use this driver. + </para> + <para> + The generic interrupt handler of <varname>uio_pdrv_genirq</varname> + will simply disable the interrupt line using + <function>disable_irq_nosync()</function>. After doing its work, + userspace can reenable the interrupt by writing 0x00000001 to the UIO + device file. The driver already implements an + <function>irq_control()</function> to make this possible, you must not + implement your own. + </para> + <para> + Using <varname>uio_pdrv_genirq</varname> not only saves a few lines of + interrupt handler code. You also do not need to know anything about + the chip's internal registers to create the kernel part of the driver. + All you need to know is the irq number of the pin the chip is + connected to. + </para> +</sect1> + </chapter> <chapter id="userspace_driver" xreflabel="Writing a driver in user space"> diff --git a/Documentation/cgroups/memcg_test.txt b/Documentation/cgroups/memcg_test.txt index 19533f93b7a..523a9c16c40 100644 --- a/Documentation/cgroups/memcg_test.txt +++ b/Documentation/cgroups/memcg_test.txt @@ -1,6 +1,6 @@ Memory Resource Controller(Memcg) Implementation Memo. -Last Updated: 2008/12/15 -Base Kernel Version: based on 2.6.28-rc8-mm. +Last Updated: 2009/1/19 +Base Kernel Version: based on 2.6.29-rc2. Because VM is getting complex (one of reasons is memcg...), memcg's behavior is complex. This is a document for memcg's internal behavior. @@ -340,3 +340,23 @@ Under below explanation, we assume CONFIG_MEM_RES_CTRL_SWAP=y. # mount -t cgroup none /cgroup -t cpuset,memory,cpu,devices and do task move, mkdir, rmdir etc...under this. + + 9.7 swapoff. + Besides management of swap is one of complicated parts of memcg, + call path of swap-in at swapoff is not same as usual swap-in path.. + It's worth to be tested explicitly. + + For example, test like following is good. + (Shell-A) + # mount -t cgroup none /cgroup -t memory + # mkdir /cgroup/test + # echo 40M > /cgroup/test/memory.limit_in_bytes + # echo 0 > /cgroup/test/tasks + Run malloc(100M) program under this. You'll see 60M of swaps. + (Shell-B) + # move all tasks in /cgroup/test to /cgroup + # /sbin/swapoff -a + # rmdir /test/cgroup + # kill malloc task. + + Of course, tmpfs v.s. swapoff test should be tested, too. diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt index bbebc3a43ac..a87be42f821 100644 --- a/Documentation/filesystems/proc.txt +++ b/Documentation/filesystems/proc.txt @@ -2027,6 +2027,34 @@ increase the likelihood of this process being killed by the oom-killer. Valid values are in the range -16 to +15, plus the special value -17, which disables oom-killing altogether for this process. +The process to be killed in an out-of-memory situation is selected among all others +based on its badness score. This value equals the original memory size of the process +and is then updated according to its CPU time (utime + stime) and the +run time (uptime - start time). The longer it runs the smaller is the score. +Badness score is divided by the square root of the CPU time and then by +the double square root of the run time. + +Swapped out tasks are killed first. Half of each child's memory size is added to +the parent's score if they do not share the same memory. Thus forking servers +are the prime candidates to be killed. Having only one 'hungry' child will make +parent less preferable than the child. + +/proc/<pid>/oom_score shows process' current badness score. + +The following heuristics are then applied: + * if the task was reniced, its score doubles + * superuser or direct hardware access tasks (CAP_SYS_ADMIN, CAP_SYS_RESOURCE + or CAP_SYS_RAWIO) have their score divided by 4 + * if oom condition happened in one cpuset and checked task does not belong + to it, its score is divided by 8 + * the resulting score is multiplied by two to the power of oom_adj, i.e. + points <<= oom_adj when it is positive and + points >>= -(oom_adj) otherwise + +The task with the highest badness score is then selected and its children +are killed, process itself will be killed in an OOM situation when it does +not have children or some of them disabled oom like described above. + 2.13 /proc/<pid>/oom_score - Display current oom-killer score ------------------------------------------------------------- diff --git a/Documentation/ja_JP/stable_kernel_rules.txt b/Documentation/ja_JP/stable_kernel_rules.txt index b3ffe870de3..14265837c4c 100644 --- a/Documentation/ja_JP/stable_kernel_rules.txt +++ b/Documentation/ja_JP/stable_kernel_rules.txt @@ -12,11 +12,11 @@ file at first. ================================== これは、 -linux-2.6.24/Documentation/stable_kernel_rules.txt +linux-2.6.29/Documentation/stable_kernel_rules.txt の和訳です。 翻訳団体： JF プロジェクト < http://www.linux.or.jp/JF/ > -翻訳日： 2007/12/30 +翻訳日： 2009/1/14 翻訳者： Tsugikazu Shibata <tshibata at ab dot jp dot nec dot com> 校正者： 武井伸光さん、<takei at webmasters dot gr dot jp> かねこさん (Seiji Kaneko) <skaneko at a2 dot mbn dot or dot jp> @@ -38,12 +38,15 @@ linux-2.6.24/Documentation/stable_kernel_rules.txt - ビルドエラー(CONFIG_BROKENになっているものを除く), oops, ハング、デー タ破壊、現実のセキュリティ問題、その他 "ああ、これはダメだね"という ようなものを修正しなければならない。短く言えば、重大な問題。 + - 新しい device ID とクオークも受け入れられる。 - どのように競合状態が発生するかの説明も一緒に書かれていない限り、 "理論的には競合状態になる"ようなものは不可。 - いかなる些細な修正も含めることはできない。(スペルの修正、空白のクリー ンアップなど) - - 対応するサブシステムメンテナが受け入れたものでなければならない。 - Documentation/SubmittingPatches の規則に従ったものでなければならない。 + - パッチ自体か同等の修正が Linus のツリーに既に存在しなければならない。 + Linus のツリーでのコミットID を -stable へのパッチ投稿の際に引用す + ること。 -stable ツリーにパッチを送付する手続き- @@ -52,8 +55,10 @@ linux-2.6.24/Documentation/stable_kernel_rules.txt - 送信者はパッチがキューに受け付けられた際には ACK を、却下された場合 には NAK を受け取る。この反応は開発者たちのスケジュールによって、数 日かかる場合がある。 - - もし受け取られたら、パッチは他の開発者たちのレビューのために - -stable キューに追加される。 + - もし受け取られたら、パッチは他の開発者たちと関連するサブシステムの + メンテナーによるレビューのために -stable キューに追加される。 + - パッチに stable@kernel.org のアドレスが付加されているときには、それ + が Linus のツリーに入る時に自動的に stable チームに email される。 - セキュリティパッチはこのエイリアス (stable@kernel.org) に送られるべ きではなく、代わりに security@kernel.org のアドレスに送られる。 diff --git a/Documentation/lguest/Makefile b/Documentation/lguest/Makefile index 725eef81cd4..1f4f9e888bd 100644 --- a/Documentation/lguest/Makefile +++ b/Documentation/lguest/Makefile @@ -1,5 +1,5 @@ # This creates the demonstration utility "lguest" which runs a Linux guest. -CFLAGS:=-Wall -Wmissing-declarations -Wmissing-prototypes -O3 -I../../include -I../../arch/x86/include +CFLAGS:=-Wall -Wmissing-declarations -Wmissing-prototypes -O3 -I../../include -I../../arch/x86/include -U_FORTIFY_SOURCE LDLIBS:=-lz all: lguest |