diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/SubmittingPatches | 46 | ||||
| -rw-r--r-- | Documentation/cpusets.txt | 9 | ||||
| -rw-r--r-- | Documentation/kernel-doc-nano-HOWTO.txt | 99 | ||||
| -rw-r--r-- | Documentation/kernel-docs.txt | 8 | ||||
| -rw-r--r-- | Documentation/networking/arcnet.txt | 2 | ||||
| -rw-r--r-- | Documentation/video4linux/CARDLIST.cx88 | 2 | ||||
| -rw-r--r-- | Documentation/video4linux/cx18.txt | 4 | ||||
| -rw-r--r-- | Documentation/vm/pagemap.txt | 77 |
8 files changed, 237 insertions, 10 deletions
diff --git a/Documentation/SubmittingPatches b/Documentation/SubmittingPatches index 9c93a03..118ca6e 100644 --- a/Documentation/SubmittingPatches +++ b/Documentation/SubmittingPatches @@ -327,6 +327,52 @@ Some people also put extra tags at the end. They'll just be ignored for now, but you can do this to mark internal company procedures or just point out some special detail about the sign-off. +If you are a subsystem or branch maintainer, sometimes you need to slightly +modify patches you receive in order to merge them, because the code is not +exactly the same in your tree and the submitters'. If you stick strictly to +rule (c), you should ask the submitter to rediff, but this is a totally +counter-productive waste of time and energy. Rule (b) allows you to adjust +the code, but then it is very impolite to change one submitter's code and +make him endorse your bugs. To solve this problem, it is recommended that +you add a line between the last Signed-off-by header and yours, indicating +the nature of your changes. While there is nothing mandatory about this, it +seems like prepending the description with your mail and/or name, all +enclosed in square brackets, is noticeable enough to make it obvious that +you are responsible for last-minute changes. Example : + + Signed-off-by: Random J Developer <random@developer.example.org> + [lucky@maintainer.example.org: struct foo moved from foo.c to foo.h] + Signed-off-by: Lucky K Maintainer <lucky@maintainer.example.org> + +This practise is particularly helpful if you maintain a stable branch and +want at the same time to credit the author, track changes, merge the fix, +and protect the submitter from complaints. Note that under no circumstances +can you change the author's identity (the From header), as it is the one +which appears in the changelog. + +Special note to back-porters: It seems to be a common and useful practise +to insert an indication of the origin of a patch at the top of the commit +message (just after the subject line) to facilitate tracking. For instance, +here's what we see in 2.6-stable : + + Date: Tue May 13 19:10:30 2008 +0000 + + SCSI: libiscsi regression in 2.6.25: fix nop timer handling + + commit 4cf1043593db6a337f10e006c23c69e5fc93e722 upstream + +And here's what appears in 2.4 : + + Date: Tue May 13 22:12:27 2008 +0200 + + wireless, airo: waitbusy() won't delay + + [backport of 2.6 commit b7acbdfbd1f277c1eb23f344f899cfa4cd0bf36a] + +Whatever the format, this information provides a valuable help to people +tracking your trees, and to people trying to trouble-shoot bugs in your +tree. + 13) When to use Acked-by: and Cc: diff --git a/Documentation/cpusets.txt b/Documentation/cpusets.txt index fb7b361..d803c5c 100644 --- a/Documentation/cpusets.txt +++ b/Documentation/cpusets.txt @@ -199,7 +199,7 @@ using the sched_setaffinity, mbind and set_mempolicy system calls. The following rules apply to each cpuset: - Its CPUs and Memory Nodes must be a subset of its parents. - - It can only be marked exclusive if its parent is. + - It can't be marked exclusive unless its parent is. - If its cpu or memory is exclusive, they may not overlap any sibling. These rules, and the natural hierarchy of cpusets, enable efficient @@ -345,7 +345,7 @@ is modified to perform an inline check for this PF_SPREAD_PAGE task flag, and if set, a call to a new routine cpuset_mem_spread_node() returns the node to prefer for the allocation. -Similarly, setting 'memory_spread_cache' turns on the flag +Similarly, setting 'memory_spread_slab' turns on the flag PF_SPREAD_SLAB, and appropriately marked slab caches will allocate pages from the node returned by cpuset_mem_spread_node(). @@ -709,7 +709,10 @@ Now you want to do something with this cpuset. In this directory you can find several files: # ls -cpus cpu_exclusive mems mem_exclusive mem_hardwall tasks +cpu_exclusive memory_migrate mems tasks +cpus memory_pressure notify_on_release +mem_exclusive memory_spread_page sched_load_balance +mem_hardwall memory_spread_slab sched_relax_domain_level Reading them will give you information about the state of this cpuset: the CPUs and Memory Nodes it can use, the processes that are using diff --git a/Documentation/kernel-doc-nano-HOWTO.txt b/Documentation/kernel-doc-nano-HOWTO.txt index 2075c06..0bd3274 100644 --- a/Documentation/kernel-doc-nano-HOWTO.txt +++ b/Documentation/kernel-doc-nano-HOWTO.txt @@ -1,6 +1,105 @@ kernel-doc nano-HOWTO ===================== +How to format kernel-doc comments +--------------------------------- + +In order to provide embedded, 'C' friendly, easy to maintain, +but consistent and extractable documentation of the functions and +data structures in the Linux kernel, the Linux kernel has adopted +a consistent style for documenting functions and their parameters, +and structures and their members. + +The format for this documentation is called the kernel-doc format. +It is documented in this Documentation/kernel-doc-nano-HOWTO.txt file. + +This style embeds the documentation within the source files, using +a few simple conventions. The scripts/kernel-doc perl script, some +SGML templates in Documentation/DocBook, and other tools understand +these conventions, and are used to extract this embedded documentation +into various documents. + +In order to provide good documentation of kernel functions and data +structures, please use the following conventions to format your +kernel-doc comments in Linux kernel source. + +We definitely need kernel-doc formatted documentation for functions +that are exported to loadable modules using EXPORT_SYMBOL. + +We also look to provide kernel-doc formatted documentation for +functions externally visible to other kernel files (not marked +"static"). + +We also recommend providing kernel-doc formatted documentation +for private (file "static") routines, for consistency of kernel +source code layout. But this is lower priority and at the +discretion of the MAINTAINER of that kernel source file. + +Data structures visible in kernel include files should also be +documented using kernel-doc formatted comments. + +The opening comment mark "/**" is reserved for kernel-doc comments. +Only comments so marked will be considered by the kernel-doc scripts, +and any comment so marked must be in kernel-doc format. Do not use +"/**" to be begin a comment block unless the comment block contains +kernel-doc formatted comments. The closing comment marker for +kernel-doc comments can be either "*/" or "**/". + +Kernel-doc comments should be placed just before the function +or data structure being described. + +Example kernel-doc function comment: + +/** + * foobar() - short function description of foobar + * @arg1: Describe the first argument to foobar. + * @arg2: Describe the second argument to foobar. + * One can provide multiple line descriptions + * for arguments. + * + * A longer description, with more discussion of the function foobar() + * that might be useful to those using or modifying it. Begins with + * empty comment line, and may include additional embedded empty + * comment lines. + * + * The longer description can have multiple paragraphs. + **/ + +The first line, with the short description, must be on a single line. + +The @argument descriptions must begin on the very next line following +this opening short function description line, with no intervening +empty comment lines. + +Example kernel-doc data structure comment. + +/** + * struct blah - the basic blah structure + * @mem1: describe the first member of struct blah + * @mem2: describe the second member of struct blah, + * perhaps with more lines and words. + * + * Longer description of this structure. + **/ + +The kernel-doc function comments describe each parameter to the +function, in order, with the @name lines. + +The kernel-doc data structure comments describe each structure member +in the data structure, with the @name lines. + +The longer description formatting is "reflowed", losing your line +breaks. So presenting carefully formatted lists within these +descriptions won't work so well; derived documentation will lose +the formatting. + +See the section below "How to add extractable documentation to your +source files" for more details and notes on how to format kernel-doc +comments. + +Components of the kernel-doc system +----------------------------------- + Many places in the source tree have extractable documentation in the form of block comments above functions. The components of this system are: diff --git a/Documentation/kernel-docs.txt b/Documentation/kernel-docs.txt index 5a4ef48..28cdc2a 100644 --- a/Documentation/kernel-docs.txt +++ b/Documentation/kernel-docs.txt @@ -715,14 +715,14 @@ * Name: "Gary's Encyclopedia - The Linux Kernel" Author: Gary (I suppose...). - URL: http://www.lisoleg.net/cgi-bin/lisoleg.pl?view=kernel.htm - Keywords: links, not found here?. + URL: http://slencyclopedia.berlios.de/index.html + Keywords: linux, community, everything! Description: Gary's Encyclopedia exists to allow the rapid finding of documentation and other information of interest to GNU/Linux users. It has about 4000 links to external pages in 150 major categories. This link is for kernel-specific links, documents, - sites... Look there if you could not find here what you were - looking for. + sites... This list is now hosted by developer.Berlios.de, + but seems not to have been updated since sometime in 1999. * Name: "The home page of Linux-MM" Author: The Linux-MM team. diff --git a/Documentation/networking/arcnet.txt b/Documentation/networking/arcnet.txt index 770fc41..7960125 100644 --- a/Documentation/networking/arcnet.txt +++ b/Documentation/networking/arcnet.txt @@ -46,7 +46,7 @@ These are the ARCnet drivers for Linux. This new release (2.91) has been put together by David Woodhouse -<dwmw2@cam.ac.uk>, in an attempt to tidy up the driver after adding support +<dwmw2@infradead.org>, in an attempt to tidy up the driver after adding support for yet another chipset. Now the generic support has been separated from the individual chipset drivers, and the source files aren't quite so packed with #ifdefs! I've changed this file a bit, but kept it in the first person from diff --git a/Documentation/video4linux/CARDLIST.cx88 b/Documentation/video4linux/CARDLIST.cx88 index 5439573..7cf5685 100644 --- a/Documentation/video4linux/CARDLIST.cx88 +++ b/Documentation/video4linux/CARDLIST.cx88 @@ -60,7 +60,7 @@ 59 -> DViCO FusionHDTV 5 PCI nano [18ac:d530] 60 -> Pinnacle Hybrid PCTV [12ab:1788] 61 -> Winfast TV2000 XP Global [107d:6f18] - 62 -> PowerColor Real Angel 330 [14f1:ea3d] + 62 -> PowerColor RA330 [14f1:ea3d] 63 -> Geniatech X8000-MT DVBT [14f1:8852] 64 -> DViCO FusionHDTV DVB-T PRO [18ac:db30] 65 -> DViCO FusionHDTV 7 Gold [18ac:d610] diff --git a/Documentation/video4linux/cx18.txt b/Documentation/video4linux/cx18.txt index 077d56e..6842c26 100644 --- a/Documentation/video4linux/cx18.txt +++ b/Documentation/video4linux/cx18.txt @@ -1,7 +1,9 @@ Some notes regarding the cx18 driver for the Conexant CX23418 MPEG encoder chip: -1) The only hardware currently supported is the Hauppauge HVR-1600. +1) The only hardware currently supported is the Hauppauge HVR-1600 + card and the Compro VideoMate H900 (note that this card only + supports analog input, it has no digital tuner!). 2) Some people have problems getting the i2c bus to work. Cause unknown. The symptom is that the eeprom cannot be read and the card is diff --git a/Documentation/vm/pagemap.txt b/Documentation/vm/pagemap.txt new file mode 100644 index 0000000..ce72c0f --- /dev/null +++ b/Documentation/vm/pagemap.txt @@ -0,0 +1,77 @@ +pagemap, from the userspace perspective +--------------------------------------- + +pagemap is a new (as of 2.6.25) set of interfaces in the kernel that allow +userspace programs to examine the page tables and related information by +reading files in /proc. + +There are three components to pagemap: + + * /proc/pid/pagemap. This file lets a userspace process find out which + physical frame each virtual page is mapped to. It contains one 64-bit + value for each virtual page, containing the following data (from + fs/proc/task_mmu.c, above pagemap_read): + + * Bits 0-55 page frame number (PFN) if present + * Bits 0-4 swap type if swapped + * Bits 5-55 swap offset if swapped + * Bits 55-60 page shift (page size = 1<<page shift) + * Bit 61 reserved for future use + * Bit 62 page swapped + * Bit 63 page present + + If the page is not present but in swap, then the PFN contains an + encoding of the swap file number and the page's offset into the + swap. Unmapped pages return a null PFN. This allows determining + precisely which pages are mapped (or in swap) and comparing mapped + pages between processes. + + Efficient users of this interface will use /proc/pid/maps to + determine which areas of memory are actually mapped and llseek to + skip over unmapped regions. + + * /proc/kpagecount. This file contains a 64-bit count of the number of + times each page is mapped, indexed by PFN. + + * /proc/kpageflags. This file contains a 64-bit set of flags for each + page, indexed by PFN. + + The flags are (from fs/proc/proc_misc, above kpageflags_read): + + 0. LOCKED + 1. ERROR + 2. REFERENCED + 3. UPTODATE + 4. DIRTY + 5. LRU + 6. ACTIVE + 7. SLAB + 8. WRITEBACK + 9. RECLAIM + 10. BUDDY + +Using pagemap to do something useful: + +The general procedure for using pagemap to find out about a process' memory +usage goes like this: + + 1. Read /proc/pid/maps to determine which parts of the memory space are + mapped to what. + 2. Select the maps you are interested in -- all of them, or a particular + library, or the stack or the heap, etc. + 3. Open /proc/pid/pagemap and seek to the pages you would like to examine. + 4. Read a u64 for each page from pagemap. + 5. Open /proc/kpagecount and/or /proc/kpageflags. For each PFN you just + read, seek to that entry in the file, and read the data you want. + +For example, to find the "unique set size" (USS), which is the amount of +memory that a process is using that is not shared with any other process, +you can go through every map in the process, find the PFNs, look those up +in kpagecount, and tally up the number of pages that are only referenced +once. + +Other notes: + +Reading from any of the files will return -EINVAL if you are not starting +the read on an 8-byte boundary (e.g., if you seeked an odd number of bytes +into the file), or if the size of the read is not a multiple of 8 bytes. |
