summaryrefslogtreecommitdiff
path: root/Documentation/timers
AgeCommit message (Collapse)AuthorFilesLines
2014-09-26Documentation: update .gitignore filesPeter Foley1-0/+1
Add some missing files to .gitignore. Push Documentation/.gitignore down into subdirectories. Signed-off-by: Peter Foley <pefoley2@pefoley.com> Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2014-09-26Documentation: use subdir-y to avoid unnecessary built-in.o filesPeter Foley1-3/+0
Change the Documentation makefiles from obj-m to subdir-y to avoid generating unnecessary built-in.o files since nothing in Documentation/ is ever linked in to vmlinux. Signed-off-by: Peter Foley <pefoley2@pefoley.com> Acked-by: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2014-07-24clocksource: document some basic timekeeping conceptsLinus Walleij2-0/+181
This adds some documentation about clock sources, clock events, the weak sched_clock() function and delay timers that answers questions that repeatedly arise on the mailing lists. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Nicolas Pitre <nico@fluxnic.net> Cc: Colin Cross <ccross@google.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: John Stultz <john.stultz@linaro.org>
2014-05-04timer_stats/doc: Fix /proc/timer_stats documentationMichael Kerrisk1-3/+3
Documentation/timers/timer_stats.txt claims: "The readout of /proc/timer_stats automatically disables sampling. The sampled information is kept until a new sample period is started. This allows multiple readouts." Some simple testing shows that reading from /proc/timer_stats does not disable sampling. Looking back over past source code, it appears that it never did. Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Randy Dunlap <rdunlap@infradead.org> Link: http://lkml.kernel.org/r/53636FB6.9060407@gmail.com [ Small tidyup of the changelog. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-02-11Documentation/: update 00-INDEX filesHenrik Austad1-0/+2
Some of the 00-INDEX files are somewhat outdated and some folders does not contain 00-INDEX at all. Only outdated (with the notably exception of spi) indexes are touched here, the 169 folders without 00-INDEX has not been touched. New 00-INDEX - spi/* was added in a series of commits dating back to 2006 Added files (missing in (*/)00-INDEX) - dmatest.txt was added by commit 851b7e16a07d ("dmatest: run test via debugfs") - this_cpu_ops.txt was added by commit a1b2a555d637 ("percpu: add documentation on this_cpu operations") - ww-mutex-design.txt was added by commit 040a0a371005 ("mutex: Add support for wound/wait style locks") - bcache.txt was added by commit cafe56359144 ("bcache: A block layer cache") - kernel-per-CPU-kthreads.txt was added by commit 49717cb40410 ("kthread: Document ways of reducing OS jitter due to per-CPU kthreads") - phy.txt was added by commit ff764963479a ("drivers: phy: add generic PHY framework") - block/null_blk was added by commit 12f8f4fc0314 ("null_blk: documentation") - module-signing.txt was added by commit 3cafea307642 ("Add Documentation/module-signing.txt file") - assoc_array.txt was added by commit 3cb989501c26 ("Add a generic associative array implementation.") - arm/IXP4xx was part of the initial repo - arm/cluster-pm-race-avoidance.txt was added by commit 7fe31d28e839 ("ARM: mcpm: introduce helpers for platform coherency exit/setup") - arm/firmware.txt was added by commit 7366b92a77fc ("ARM: Add interface for registering and calling firmware-specific operations") - arm/kernel_mode_neon.txt was added by commit 2afd0a05241d ("ARM: 7825/1: document the use of NEON in kernel mode") - arm/tcm.txt was added by commit bc581770cfdd ("ARM: 5580/2: ARM TCM (Tightly-Coupled Memory) support v3") - arm/vlocks.txt was added by commit 9762f12d3e05 ("ARM: mcpm: Add baremetal voting mutexes") - blackfin/gptimers-example.c, Makefile was added by commit 4b60779d5ea7 ("Blackfin: add an example showing how to use the gptimers API") - devicetree/usage-model.txt was added by commit 31134efc681a ("dt: Linux DT usage model documentation") - fb/api.txt was added by commit fb21c2f42879 ("fbdev: Add FOURCC-based format configuration API") - fb/sm501.txt was added by commit e6a049807105 ("video, sm501: add edid and commandline support") - fb/udlfb.txt was added by commit 96f8d864afd6 ("fbdev: move udlfb out of staging.") - filesystems/Makefile was added by commit 1e0051ae48a2 ("Documentation/fs/: split txt and source files") - filesystems/nfs/nfsd-admin-interfaces.txt was added by commit 8a4c6e19cfed ("nfsd: document kernel interfaces for nfsd configuration") - ide/warm-plug-howto.txt was added by commit f74c91413ec6 ("ide: add warm-plug support for IDE devices (take 2)") - laptops/Makefile was added by commit d49129accc21 ("Documentation/laptop/: split txt and source files") - leds/leds-blinkm.txt was added by commit b54cf35a7f65 ("LEDS: add BlinkM RGB LED driver, documentation and update MAINTAINERS") - leds/ledtrig-oneshot.txt was added by commit 5e417281cde2 ("leds: add oneshot trigger") - leds/ledtrig-transient.txt was added by commit 44e1e9f8e705 ("leds: add new transient trigger for one shot timer activation") - m68k/README.buddha was part of the initial repo - networking/LICENSE.(qla3xxx|qlcnic|qlge) was added by commits 40839129f779, c4e84bde1d59, 5a4faa873782 - networking/Makefile was added by commit 3794f3e812ef ("docsrc: build Documentation/ sources") - networking/i40evf.txt was added by commit 105bf2fe6b32 ("i40evf: add driver to kernel build system") - networking/ipsec.txt was added by commit b3c6efbc36e2 ("xfrm: Add file to document IPsec corner case") - networking/mac80211-auth-assoc-deauth.txt was added by commit 3cd7920a2be8 ("mac80211: add auth/assoc/deauth flow diagram") - networking/netlink_mmap.txt was added by commit 5683264c3981 ("netlink: add documentation for memory mapped I/O") - networking/nf_conntrack-sysctl.txt was added by commit c9f9e0e1597f ("netfilter: doc: add nf_conntrack sysctl api documentation") lan) - networking/team.txt was added by commit 3d249d4ca7d0 ("net: introduce ethernet teaming device") - networking/vxlan.txt was added by commit d342894c5d2f ("vxlan: virtual extensible lan") - power/runtime_pm.txt was added by commit 5e928f77a09a ("PM: Introduce core framework for run-time PM of I/O devices (rev. 17)") - power/charger-manager.txt was added by commit 3bb3dbbd56ea ("power_supply: Add initial Charger-Manager driver") - RCU/lockdep-splat.txt was added by commit d7bd2d68aa2e ("rcu: Document interpretation of RCU-lockdep splats") - s390/kvm.txt was added by 5ecee4b (KVM: s390: API documentation) - s390/qeth.txt was added by commit b4d72c08b358 ("qeth: bridgeport support - basic control") - scheduler/sched-bwc.txt was added by commit 88ebc08ea9f7 ("sched: Add documentation for bandwidth control") - scsi/advansys.txt was added by commit 4bd6d7f35661 ("[SCSI] advansys: Move documentation to Documentation/scsi") - scsi/bfa.txt was added by commit 1ec90174bdb4 ("[SCSI] bfa: add readme file") - scsi/bnx2fc.txt was added by commit 12b8fc10eaf4 ("[SCSI] bnx2fc: Add driver documentation") - scsi/cxgb3i.txt was added by commit c3673464ebc0 ("[SCSI] cxgb3i: Add cxgb3i iSCSI driver.") - scsi/hpsa.txt was added by commit 992ebcf14f3c ("[SCSI] hpsa: Add hpsa.txt to Documentation/scsi") - scsi/link_power_management_policy.txt was added by commit ca77329fb713 ("[libata] Link power management infrastructure") - scsi/osd.txt was added by commit 78e0c621deca ("[SCSI] osd: Documentation for OSD library") - scsi/scsi-parameter.txt was created/moved by commit 163475fb111c ("Documentation: move SCSI parameters to their own text file") - serial/driver was part of the initial repo - serial/n_gsm.txt was added by commit 323e84122ec6 ("n_gsm: add a documentation") - timers/Makefile was added by commit 3794f3e812ef ("docsrc: build Documentation/ sources") - virt/kvm/s390.txt was added by commit d9101fca3d57 ("KVM: s390: diagnose call documentation") - vm/split_page_table_lock was added by commit 49076ec2ccaf ("mm: dynamically allocate page->ptl if it cannot be embedded to struct page") - w1/slaves/w1_ds28e04 was added by commit fbf7f7b4e2ae ("w1: Add 1-wire slave device driver for DS28E04-100") - w1/masters/omap-hdq was added by commit e0a29382c6f5 ("hdq: documentation for OMAP HDQ") - x86/early-microcode.txt was added by commit 0d91ea86a895 ("x86, doc: Documentation for early microcode loading") - x86/earlyprintk.txt was added by commit a1aade478862 ("x86/doc: mini-howto for using earlyprintk=dbgp") - x86/entry_64.txt was added by commit 8b4777a4b50c ("x86-64: Document some of entry_64.S") - x86/pat.txt was added by commit d27554d874c7 ("x86: PAT documentation") Moved files - arm/kernel_user_helpers.txt was moved out of arch/arm/kernel by commit 37b8304642c7 ("ARM: kuser: move interface documentation out of the source code") - efi-stub.txt was moved out of x86/ and down into Documentation/ in commit 4172fe2f8a47 ("EFI stub documentation updates") - laptops/hpfall.c was moved out of hwmon/ and into laptops/ in commit efcfed9bad88 ("Move hp_accel to drivers/platform/x86") - commit 5616c23ad9cd ("x86: doc: move x86-generic documentation from Doc/x86/i386"): * x86/usb-legacy-support.txt * x86/boot.txt * x86/zero_page.txt - power/video_extension.txt was moved to acpi in commit 70e66e4df191 ("ACPI / video: move video_extension.txt to Documentation/acpi") Removed files (left in 00-INDEX) - memory.txt was removed by commit 00ea8990aadf ("memory.txt: remove stray information") - gpio.txt was moved to gpio/ in commit fd8e198cfcaa ("Documentation: gpiolib: document new interface") - networking/DLINK.txt was removed by commit 168e06ae26dd ("drivers/net: delete old parallel port de600/de620 drivers") - serial/hayes-esp.txt was removed by commit f53a2ade0bb9 ("tty: esp: remove broken driver") - s390/TAPE was removed by commit 9e280f669308 ("[S390] remove tape block docu") - vm/locking was removed by commit 57ea8171d2bc ("mm: documentation: remove hopelessly out-of-date locking doc") - laptops/acer-wmi.txt was remvoed by commit 020036678e81 ("acer-wmi: Delete out-of-date documentation") Typos/misc issues - rpc-server-gss.txt was added as knfsd-rpcgss.txt in commit 030d794bf498 ("SUNRPC: Use gssproxy upcall for server RPCGSS authentication.") - commit b88cf73d9278 ("net: add missing entries to Documentation/networking/00-INDEX") * generic-hdlc.txt was added as generic_hdlc.txt * spider_net.txt was added as spider-net.txt - w1/master/mxc-w1 was added as mxc_w1 by commit a5fd9139f74c ("w1: add 1-wire master driver for i.MX27 / i.MX31") - s390/zfcpdump.txt was added as zfcpdump by commit 6920c12a407e ("[S390] Add Documentation/s390/00-INDEX.") Signed-off-by: Henrik Austad <henrik@austad.us> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> [rcu bits] Acked-by: Rob Landley <rob@landley.net> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Rob Herring <robh+dt@kernel.org> Cc: David S. Miller <davem@davemloft.net> Cc: Mark Brown <broonie@kernel.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Gleb Natapov <gleb@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Len Brown <len.brown@intel.com> Cc: James Bottomley <JBottomley@parallels.com> Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-10-28doc: add missing files to timers/00-INDEXHenrik Austad1-0/+4
- timers-howto was added by commit 0fcb8081 (Documentation: Add timers/timers-howto.txt) - NO_HZ was added by commit 0c87f9b5 (nohz_full: Add documentation.) Cc: Patrick Pannuto <ppannuto@codeaurora.org> Signed-off-by: Henrik Austad <haustad@cisco.com> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-08-19nohz_full: Add testing information to documentationPaul E. McKenney1-10/+34
This commit adds information about testing nohz_full, and also emphasizes the fact that you need a multi-CPU system to get any benefit from nohz_full. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2013-06-11nohz_full: Document additional restrictionsPaul E. McKenney1-3/+18
This commit calls out the potential for slowing the tick even when there are multiple runnable processes per CPU, It also points out that current mainlined version keeps the tick going on at least one CPU even when all CPUs are otherwise idle. Finally, it notes the need for a 1-HZ tick in order to calculate CPU load, maintain sched average, compute CFS entity vruntime, compute avenrun, and carry out load balancing. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2013-06-11nohz_full: Update based on Sedat Dilek reviewPaul E. McKenney1-9/+49
Make it more clear that there are three options, and give hints as to which of the three is most likely to be useful in different situations. Reported-by: Sedat Dilek <sedat.dilek@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2013-04-28nohz_full: Add documentation.Paul E. McKenney1-0/+273
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Kevin Hilman <khilman@linaro.org> Cc: Christoph Lameter <cl@linux.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Olivier Baetz <olivier.baetz@novasparks.com> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Kevin Hilman <khilman@linaro.org>
2011-09-27doc: fix broken referencesPaul Bolle1-1/+1
There are numerous broken references to Documentation files (in other Documentation files, in comments, etc.). These broken references are caused by typo's in the references, and by renames or removals of the Documentation files. Some broken references are simply odd. Fix these broken references, sometimes by dropping the irrelevant text they were part of. Signed-off-by: Paul Bolle <pebolle@tiscali.nl> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-05-17doc: timers-howto: fix a typo ("unsgined")Jonathan Neuschäfer1-1/+1
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-11-01tree-wide: fix comment/printk typosUwe Kleine-König1-1/+1
"gadget", "through", "command", "maintain", "maintain", "controller", "address", "between", "initiali[zs]e", "instead", "function", "select", "already", "equal", "access", "management", "hierarchy", "registration", "interest", "relative", "memory", "offset", "already", Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-10-27Documentation/timers/hpet_example.c: add supporting info for hpet_exampleJaswinder Singh Rajput1-0/+27
$./hpet_example info /dev/hpet -hpet: executing info hpet_info: hi_irqfreq 0x0 hi_flags 0x0 hi_hpet 0 hi_timer 2 Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com> Cc: Clemens Ladisch <clemens@ladisch.de> Cc: "Venkatesh Pallipadi (Venki)" <venki@google.com> Cc: john stultz <johnstul@us.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-04Documentation: Add timers/timers-howto.txtPatrick Pannuto1-0/+105
This file seeks to explain the nuances in various delays; many driver writers are not necessarily familiar with the various kernel timers, their shortfalls, and quirks. When faced with ndelay, udelay, mdelay, usleep_range, msleep, and msleep_interrubtible the question "How do I just wait 1 ms for my hardware to latch?" has the non-intuitive "best" answer: usleep_range(1000,1500) This patch is followed by a series of checkpatch additions that seek to help kernel hackers pick the best delay. Signed-off-by: Patrick Pannuto <ppannuto@codeaurora.org> Cc: apw@canonical.com Cc: corbet@lwn.net Cc: arjan@linux.intel.com Cc: Randy Dunlap <rdunlap@xenotime.net> Cc: Andrew Morton <akpm@linux-foundation.org> LKML-Reference: <1280786467-26999-3-git-send-email-ppannuto@codeaurora.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2010-06-01Documentation/timers/hpet_example.c: only build on X86Randy Dunlap1-1/+1
We should only build hpet_example on x86[-64], where it is implemented. It can cause build errors on other architectures. Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Reported-by: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Arjan van de Ven <arjan@infradead.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-24Documentation/timers/hpet_example: drop duplicate header filesAndrea Gelmini1-2/+0
Documentation/timers/hpet_example.c: fcntl.h is included more than once. Documentation/timers/hpet_example.c: signal.h is included more than once. Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-13Documentation/timers/: split txt and source filesRandy Dunlap4-271/+281
Documentation/timers/hpet.txt: Expose example and tool source files in the Documentation/timers/ directory in their own files instead of being buried (almost hidden) in readme/txt files. This should help to prevent bitrot. This will make them more visible/usable to users who may need to use them, to developers who may need to test with them, and to anyone who would fix/update them if they were more visible. Also, if any of these possibly should not be in the kernel tree at all, it will be clearer that they are here and we can discuss if they should be removed. Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-11-09fix URL in hpet.txtAmerigo Wang1-1/+1
That URL is out of date. Update it. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Randy Dunlap <rdunlap@xenotime.net> Cc: Matt LaPlante <kernel1@cyberdogtech.com> Cc: Jiri Kosina <jkosina@suse.cz> Signed-off-by: WANG Cong <amwang@redhat.com> Acked-by: Matt LaPlante <kernel@cyberdogtech.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-06-12trivial: Miscellaneous documentation typo fixesMatt LaPlante2-2/+2
Fix various typos in documentation txts. Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2008-07-31hpet: /dev/hpet - fixes and cleanupDavid Brownell1-22/+21
Minor /dev/hpet updates and bugfixes: * Remove dead code, mostly remnants of an incomplete/unusable kernel interface ... noted when addressing "sparse" warnings: + hpet_unregister() and a routine it calls + hpet_task and all references, including hpet_task_lock + hpet_data.hd_flags (and HPET_DATA_PLATFORM) * Correct and improve boot message: + displays *counter* (shared between comparators) bit width, not *timer* bit widths (which are often mixed) + relabel "timers" as "comparators"; this is less confusing, they are not independent like normal timers are (sigh) + display MHz not Hz; it's never less than 10 MHz. * Tighten and correct the userspace interface code + don't accidentally program comparators in 64-bit mode using 32-bit values ... always force comparators into 32-bit mode + provide the correct bit definition flagging comparators with periodic capability ... the ABI is unchanged * Update Documentation/hpet.txt + be more correct and current + expand description a bit + don't mention that now-gone kernel interface Plus, add a FIXME comment for something that could cause big trouble on systems with more capable HPETs than at least Intel seems to ship. It seems that few folk use this userspace interface; it's not very usable given the general lack of HPET IRQ routing. I'm told that the only real point of it any more is to mmap for fast timestamps; IMO that's handled better through the gettimeofday() vsyscall. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Acked-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-31Merge branch 'linus' into timers/hpetIngo Molnar1-1/+1
2008-07-26Documentation cleanup: trivial misspelling, punctuation, and grammar ↵Matt LaPlante1-1/+1
corrections. Cc: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24documentation: move hpet.txt to timers/ subdirectoryRandy Dunlap2-0/+310
Move hpet.txt to Documentation/timers/ subdirectory. Add 00-INDEX to Documentation/timers/ subdirectory. Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: tglx <tglx@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-04-17Documentation: move timer related documentation to a single placeThomas Gleixner3-0/+500
We have two directories with timer related information in Documentation/: hrtimers/ and hrtimer/. timer_stats are not restricted to hrtimers. Move all those files into Documentation/timers where we can pile up other timer related docs as well. Pointed-out-by: Randy Dunlap <randy@oracle.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
generated by cgit v1.2.3 (git 2.39.0) at 2024-11-24 00:09:40 +0300