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2009-12-05V4L/DVB (13518): spec: regenerate videodev2.h.xmlHans Verkuil
After excluding .h.xml from the whitespace to tab conversion I had to regenerate this xml file. The only changes here are whitespace changes. If we change videodev2.h in the future, then videodev2.h.xml will only show that same change and no more unrelated whitespace changes. Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2009-12-05V4L/DVB (13476): spec: remove old dvb-spec and v4l2-spec directoriesHans Verkuil
It was really confusing to have media-specs, v4l2-spec and dvb-spec. So this patch removes v4l2-spec and dvb-spec. The docs in dvb-spec and the V4L1_API.html file were moved to media-specs/old-docs. Removed all references to v4l2-spec and dvb-spec. Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2009-12-05V4L/DVB (13471): v4l2 doc: Added FBUF_CAP_SRC_CHROMAKEY/FLAG_SRC_CHROMAKEYVaibhav Hiremath
Signed-off-by: Vaibhav Hiremath <hvaibhav@ti.com> Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2009-12-05V4L/DVB (13470): V4L2: Add Capability and Flag field for Chroma KeyVaibhav Hiremath
Signed-off-by: Vaibhav Hiremath <hvaibhav@ti.com> Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2009-12-05V4L/DVB (13468): v4l2 doc: Added ROTATE and BG_COLOR control documentationVaibhav Hiremath
Signed-off-by: Vaibhav Hiremath <hvaibhav@ti.com> Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2009-12-05V4L/DVB (13467): V4L2: Added CID's V4L2_CID_ROTATE/BG_COLORVaibhav Hiremath
Signed-off-by: Vaibhav Hiremath <hvaibhav@ti.com> Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2009-12-05V4L/DVB (13460): v4l2-spec: add missing V4L2-PIX-FMT-STV0680 description.Hans Verkuil
[mchehab@redhat.com: fix the wrong videodev2.h.xml file] Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2009-12-05V4L/DVB (13438): zr364xx: add support for Trust Powerc@m 910ZAntoine Jacquet
Tested-by: Enrique Dominguez <enrique.pinos@gmail.com> Signed-off-by: Antoine Jacquet <royale@zerezo.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2009-12-05V4L/DVB (13420): gspca - doc: Change the name of some webcams.Jean-Francois Moine
Signed-off-by: Jean-Francois Moine <moinejf@free.fr> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2009-12-05V4L/DVB (13407): Add Prof 7301 PCI DVB-S2 cardIgor M. Liplianin
Add Prof 7301 PCI DVB-S2 card The card based on stv0903 demod, stb6100 tuner. Signed-off-by: Igor M. Liplianin <liplianin@me.by> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2009-12-05V4L/DVB (13375): cx23885: Add support for Mygica X8558Pro DMB-THDavid T. L. Wong
Adds support for cx23885 card Mygica X8558 Pro DMB-TH Signed-off-by: David T. L. Wong <davidtlwong@gmail.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2009-12-05V4L/DVB (13347): cx23885: add digital television support for Hauppauge ↵Michael Krufky
WinTV-HVR1290 Signed-off-by: Michael Krufky <mkrufky@kernellabs.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2009-12-05V4L/DVB (13249): gspca - pac7311: Webcam 093a:2628 added.Jean-Francois Moine
Signed-off-by: Jean-Francois Moine <moinejf@free.fr> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2009-12-05V4L/DVB (13243): gscpa_mr97310a: Add Trust Spyc@m 100 USB IDAurelien Jacobs
gscpa_mr97310a: Add Trust Spyc@m 100 USB ID Signed-off-by: Aurelien Jacobs <aurel@gnuage.org> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2009-12-05V4L/DVB (13204): saa7134: add support for the Leadtek DTV1000SMichael Krufky
Thanks to Terry Wu for finding the GPIOs required for svideo / composite input Cc: Terry Wu <terrywu2009@gmail.com> Signed-off-by: Michael Krufky <mkrufky@kernellabs.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2009-12-05V4L/DVB (13168): Add support for Asus Europa Hybrid DVB-T card (SAA7134 ↵Danny Wood
SubVendor ID: 0x1043 Device ID: 0x4847) Adds the device IDs and driver linking to allow the Asus Europa DVB-T card to operate with these drivers. The device has a SAA7134 chipset with a TD1316 Hybrid Tuner. All inputs work on the card including switching between DVB-T and Analogue TV, there is also no IR with this card. [mchehab@redhat.com: CodingStyle fixes] Signed-off-by: Danny Wood <danwood76@gmail.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2009-12-05V4L/DVB (13164): DocBook/dvb: Starts documenting DVBS2API ioctlsMauro Carvalho Chehab
DVBS2API introduced two new ioctls that allows changing/getting details about newer video standards like DVB-S2 and ISDB-T. There are lots of thing to do in this chapter, but, for now, just add a session there, in order to allow make to not complain about undefined symbol. With this patch, all ioctls at the frontend.h API were somehow documented. Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2009-12-05V4L/DVB (13163): Docbook/dvb: Rename isdbt.xml to dvbproperty.xmlMauro Carvalho Chehab
We'll need to add the documentation for FE_[GET|SET]_PROPERTY that is not specific to isdb-t. Instead of doing it at frontend.xml, it is better to have a separate session for it. Also, isdbt.xml assumes that those ioctls were already introduced, and documents several exisiting properties. So, better to just rename it and add the documentation for it, together with each existing property there. Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2009-12-05V4L/DVB (13162): Docbook/dvb: add missing specs for ↵Mauro Carvalho Chehab
FE_DISHNETWORK_SEND_LEGACY_CMD ioctl While this ioctl should not be used, and is a good canditate for Documentation/feature-removal-schedule.txt, while it is on kernel, it needs to be documented. Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2009-12-05V4L/DVB (13161): Add missing specs for FE_SET_FRONTEND_TUNE_MODE ioctl.Mauro Carvalho Chehab
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2009-12-05V4L/DVB (13160): DocBook/Makefile: add linux/dvb/frontend.h header fileMauro Carvalho Chehab
Adds linux/dvb/frontend.h header file at DocBook, and creates cross-references for the frontend ioctls. Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2009-12-05V4L/DVB (13159): DocBook/frontend: use cross references for ioctlsMauro Carvalho Chehab
Rename all sessions id's for frontend ioctls to match ioctl name and add the proper cross-link references for those ioctls. This also helps to identify what ioctls are missing specs. Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2009-12-05V4L/DVB (13116): gspca - ov519: Webcam 041e:4067 added.Rafal Milecki
Signed-off-by: Rafal Milecki <zajec5@gmail.com> Signed-off-by: Jean-Francois Moine <moinejf@free.fr> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2009-12-05V4L/DVB (13077): em28xx: Add support for new variant of KWorld 2800dDevin Heitmueller
Seems that the reference design used for the KWorld 2800d switched from the em2860 to em2862, so we need to add the new USB id (and the i2c hash remains so all we need is the default em2862 id. Thanks to Ian Young for reporting the issue and testing the fix. Cc: Ian Young <ian@duffrecords.com> Signed-off-by: Devin Heitmueller <dheitmueller@kernellabs.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2009-12-05Merge branch 'tracing-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'tracing-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (40 commits) tracing: Separate raw syscall from syscall tracer ring-buffer-benchmark: Add parameters to set produce/consumer priorities tracing, function tracer: Clean up strstrip() usage ring-buffer benchmark: Run producer/consumer threads at nice +19 tracing: Remove the stale include/trace/power.h tracing: Only print objcopy version warning once from recordmcount tracing: Prevent build warning: 'ftrace_graph_buf' defined but not used ring-buffer: Move access to commit_page up into function used tracing: do not disable interrupts for trace_clock_local ring-buffer: Add multiple iterations between benchmark timestamps kprobes: Sanitize struct kretprobe_instance allocations tracing: Fix to use __always_unused attribute compiler: Introduce __always_unused tracing: Exit with error if a weak function is used in recordmcount.pl tracing: Move conditional into update_funcs() in recordmcount.pl tracing: Add regex for weak functions in recordmcount.pl tracing: Move mcount section search to front of loop in recordmcount.pl tracing: Fix objcopy revision check in recordmcount.pl tracing: Check absolute path of input file in recordmcount.pl tracing: Correct the check for number of arguments in recordmcount.pl ...
2009-12-05Merge branch 'core-signal-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'core-signal-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: signal: Print warning message when dropping signals signal: Fix alternate signal stack check
2009-12-05Merge branch 'core-rcu-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (31 commits) rcu: Make RCU's CPU-stall detector be default rcu: Add expedited grace-period support for preemptible RCU rcu: Enable fourth level of TREE_RCU hierarchy rcu: Rename "quiet" functions rcu: Re-arrange code to reduce #ifdef pain rcu: Eliminate unneeded function wrapping rcu: Fix grace-period-stall bug on large systems with CPU hotplug rcu: Eliminate __rcu_pending() false positives rcu: Further cleanups of use of lastcomp rcu: Simplify association of forced quiescent states with grace periods rcu: Accelerate callback processing on CPUs not detecting GP end rcu: Mark init-time-only rcu_bootup_announce() as __init rcu: Simplify association of quiescent states with grace periods rcu: Rename dynticks_completed to completed_fqs rcu: Enable synchronize_sched_expedited() fastpath rcu: Remove inline from forward-referenced functions rcu: Fix note_new_gpnum() uses of ->gpnum rcu: Fix synchronization for rcu_process_gp_end() uses of ->completed counter rcu: Prepare for synchronization fixes: clean up for non-NO_HZ handling of ->completed counter rcu: Cleanup: balance rcu_irq_enter()/rcu_irq_exit() calls ...
2009-12-05Merge branch 'next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6 * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6: (30 commits) TOMOYO: Add recursive directory matching operator support. remove CONFIG_SECURITY_FILE_CAPABILITIES compile option SELinux: print denials for buggy kernel with unknown perms Silence the existing API for capability version compatibility check. LSM: Move security_path_chmod()/security_path_chown() to after mutex_lock(). SELinux: header generation may hit infinite loop selinux: Fix warnings security: report the module name to security_module_request Config option to set a default LSM sysctl: require CAP_SYS_RAWIO to set mmap_min_addr tpm: autoload tpm_tis based on system PnP IDs tpm_tis: TPM_STS_DATA_EXPECT workaround define convenient securebits masks for prctl users (v2) tpm: fix header for modular build tomoyo: improve hash bucket dispersion tpm add default function definitions LSM: imbed ima calls in the security hooks SELinux: add .gitignore files for dynamic classes security: remove root_plug SELinux: fix locking issue introduced with c6d3aaa4e35c71a3 ...
2009-12-05Merge git://git.kernel.org/pub/scm/linux/kernel/git/brodo/pcmcia-2.6Linus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/brodo/pcmcia-2.6: (50 commits) pcmcia: rework the irq_req_t typedef pcmcia: remove deprecated handle_to_dev() macro pcmcia: pcmcia_request_window() doesn't need a pointer to a pointer pcmcia: remove unused "window_t" typedef pcmcia: move some window-related code to pcmcia_ioctl.c pcmcia: Change window_handle_t logic to unsigned long pcmcia: Pass struct pcmcia_socket to pcmcia_get_mem_page() pcmcia: Pass struct pcmcia_device to pcmcia_map_mem_page() pcmcia: Pass struct pcmcia_device to pcmcia_release_window() drivers/pcmcia: remove unnecessary kzalloc pcmcia: correct handling for Zoomed Video registers in topic.h pcmcia: fix printk formats pcmcia: autoload module pcmcia pcmcia/staging: update comedi drivers PCMCIA: stop duplicating pci_irq in soc_pcmcia_socket PCMCIA: ss: allow PCI IRQs > 255 PCMCIA: soc_common: remove 'dev' member from soc_pcmcia_socket PCMCIA: soc_common: constify soc_pcmcia_socket ops member PCMCIA: sa1111: remove duplicated initializers PCMCIA: sa1111: wrap soc_pcmcia_socket to contain sa1111 specific data ...
2009-12-03Merge branch 'master' into nextJames Morris
2009-12-01SLOW_WORK: Move slow_work's proc file to debugfsDavid Howells
Move slow_work's debugging proc file to debugfs. Signed-off-by: David Howells <dhowells@redhat.com> Requested-and-acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-11-30fbdev: Migrate mailing lists to vgerGeert Uytterhoeven
The fbdev mailing lists at SourceForge have been migrated to a single mailing list at kernel.org: linux-fbdev@vger.kernel.org. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-11-30Merge git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-2.6-fscacheLinus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-2.6-fscache: (31 commits) FS-Cache: Provide nop fscache_stat_d() if CONFIG_FSCACHE_STATS=n SLOW_WORK: Fix GFS2 to #include <linux/module.h> before using THIS_MODULE SLOW_WORK: Fix CIFS to pass THIS_MODULE to slow_work_register_user() CacheFiles: Don't log lookup/create failing with ENOBUFS CacheFiles: Catch an overly long wait for an old active object CacheFiles: Better showing of debugging information in active object problems CacheFiles: Mark parent directory locks as I_MUTEX_PARENT to keep lockdep happy CacheFiles: Handle truncate unlocking the page we're reading CacheFiles: Don't write a full page if there's only a partial page to cache FS-Cache: Actually requeue an object when requested FS-Cache: Start processing an object's operations on that object's death FS-Cache: Make sure FSCACHE_COOKIE_LOOKING_UP cleared on lookup failure FS-Cache: Add a retirement stat counter FS-Cache: Handle pages pending storage that get evicted under OOM conditions FS-Cache: Handle read request vs lookup, creation or other cache failure FS-Cache: Don't delete pending pages from the page-store tracking tree FS-Cache: Fix lock misorder in fscache_write_op() FS-Cache: The object-available state can't rely on the cookie to be available FS-Cache: Permit cache retrieval ops to be interrupted in the initial wait phase FS-Cache: Use radix tree preload correctly in tracking of pages to be stored ...
2009-11-19Merge branch 'upstream-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jlbec/ocfs2 * 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jlbec/ocfs2: ocfs2: Trivial cleanup of jbd compatibility layer removal ocfs2: Refresh documentation ocfs2: return f_fsid info in ocfs2_statfs() ocfs2: duplicate inline data properly during reflink. ocfs2: Move ocfs2_complete_reflink to the right place. ocfs2: Return -EINVAL when a device is not ocfs2.
2009-11-19CacheFiles: Catch an overly long wait for an old active objectDavid Howells
Catch an overly long wait for an old, dying active object when we want to replace it with a new one. The probability is that all the slow-work threads are hogged, and the delete can't get a look in. What we do instead is: (1) if there's nothing in the slow work queue, we sleep until either the dying object has finished dying or there is something in the slow work queue behind which we can queue our object. (2) if there is something in the slow work queue, we return ETIMEDOUT to fscache_lookup_object(), which then puts us back on the slow work queue, presumably behind the deletion that we're blocked by. We are then deferred for a while until we work our way back through the queue - without blocking a slow-work thread unnecessarily. A backtrace similar to the following may appear in the log without this patch: INFO: task kslowd004:5711 blocked for more than 120 seconds. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kslowd004 D 0000000000000000 0 5711 2 0x00000080 ffff88000340bb80 0000000000000046 ffff88002550d000 0000000000000000 ffff88002550d000 0000000000000007 ffff88000340bfd8 ffff88002550d2a8 000000000000ddf0 00000000000118c0 00000000000118c0 ffff88002550d2a8 Call Trace: [<ffffffff81058e21>] ? trace_hardirqs_on+0xd/0xf [<ffffffffa011c4d8>] ? cachefiles_wait_bit+0x0/0xd [cachefiles] [<ffffffffa011c4e1>] cachefiles_wait_bit+0x9/0xd [cachefiles] [<ffffffff81353153>] __wait_on_bit+0x43/0x76 [<ffffffff8111ae39>] ? ext3_xattr_get+0x1ec/0x270 [<ffffffff813531ef>] out_of_line_wait_on_bit+0x69/0x74 [<ffffffffa011c4d8>] ? cachefiles_wait_bit+0x0/0xd [cachefiles] [<ffffffff8104c125>] ? wake_bit_function+0x0/0x2e [<ffffffffa011bc79>] cachefiles_mark_object_active+0x203/0x23b [cachefiles] [<ffffffffa011c209>] cachefiles_walk_to_object+0x558/0x827 [cachefiles] [<ffffffffa011a429>] cachefiles_lookup_object+0xac/0x12a [cachefiles] [<ffffffffa00aa1e9>] fscache_lookup_object+0x1c7/0x214 [fscache] [<ffffffffa00aafc5>] fscache_object_state_machine+0xa5/0x52d [fscache] [<ffffffffa00ab4ac>] fscache_object_slow_work_execute+0x5f/0xa0 [fscache] [<ffffffff81082093>] slow_work_execute+0x18f/0x2d1 [<ffffffff8108239a>] slow_work_thread+0x1c5/0x308 [<ffffffff8104c0f1>] ? autoremove_wake_function+0x0/0x34 [<ffffffff810821d5>] ? slow_work_thread+0x0/0x308 [<ffffffff8104be91>] kthread+0x7a/0x82 [<ffffffff8100beda>] child_rip+0xa/0x20 [<ffffffff8100b87c>] ? restore_args+0x0/0x30 [<ffffffff8104be17>] ? kthread+0x0/0x82 [<ffffffff8100bed0>] ? child_rip+0x0/0x20 1 lock held by kslowd004/5711: #0: (&sb->s_type->i_mutex_key#7/1){+.+.+.}, at: [<ffffffffa011be64>] cachefiles_walk_to_object+0x1b3/0x827 [cachefiles] Signed-off-by: David Howells <dhowells@redhat.com>
2009-11-19FS-Cache: Start processing an object's operations on that object's deathDavid Howells
Start processing an object's operations when that object moves into the DYING state as the object cannot be destroyed until all its outstanding operations have completed. Furthermore, make sure that read and allocation operations handle being woken up on a dead object. Such events are recorded in the Allocs.abt and Retrvls.abt statistics as viewable through /proc/fs/fscache/stats. The code for waiting for object activation for the read and allocation operations is also extracted into its own function as it is much the same in all cases, differing only in the stats incremented. Signed-off-by: David Howells <dhowells@redhat.com>
2009-11-19FS-Cache: Handle pages pending storage that get evicted under OOM conditionsDavid Howells
Handle netfs pages that the vmscan algorithm wants to evict from the pagecache under OOM conditions, but that are waiting for write to the cache. Under these conditions, vmscan calls the releasepage() function of the netfs, asking if a page can be discarded. The problem is typified by the following trace of a stuck process: kslowd005 D 0000000000000000 0 4253 2 0x00000080 ffff88001b14f370 0000000000000046 ffff880020d0d000 0000000000000007 0000000000000006 0000000000000001 ffff88001b14ffd8 ffff880020d0d2a8 000000000000ddf0 00000000000118c0 00000000000118c0 ffff880020d0d2a8 Call Trace: [<ffffffffa00782d8>] __fscache_wait_on_page_write+0x8b/0xa7 [fscache] [<ffffffff8104c0f1>] ? autoremove_wake_function+0x0/0x34 [<ffffffffa0078240>] ? __fscache_check_page_write+0x63/0x70 [fscache] [<ffffffffa00b671d>] nfs_fscache_release_page+0x4e/0xc4 [nfs] [<ffffffffa00927f0>] nfs_release_page+0x3c/0x41 [nfs] [<ffffffff810885d3>] try_to_release_page+0x32/0x3b [<ffffffff81093203>] shrink_page_list+0x316/0x4ac [<ffffffff8109372b>] shrink_inactive_list+0x392/0x67c [<ffffffff813532fa>] ? __mutex_unlock_slowpath+0x100/0x10b [<ffffffff81058df0>] ? trace_hardirqs_on_caller+0x10c/0x130 [<ffffffff8135330e>] ? mutex_unlock+0x9/0xb [<ffffffff81093aa2>] shrink_list+0x8d/0x8f [<ffffffff81093d1c>] shrink_zone+0x278/0x33c [<ffffffff81052d6c>] ? ktime_get_ts+0xad/0xba [<ffffffff81094b13>] try_to_free_pages+0x22e/0x392 [<ffffffff81091e24>] ? isolate_pages_global+0x0/0x212 [<ffffffff8108e743>] __alloc_pages_nodemask+0x3dc/0x5cf [<ffffffff81089529>] grab_cache_page_write_begin+0x65/0xaa [<ffffffff8110f8c0>] ext3_write_begin+0x78/0x1eb [<ffffffff81089ec5>] generic_file_buffered_write+0x109/0x28c [<ffffffff8103cb69>] ? current_fs_time+0x22/0x29 [<ffffffff8108a509>] __generic_file_aio_write+0x350/0x385 [<ffffffff8108a588>] ? generic_file_aio_write+0x4a/0xae [<ffffffff8108a59e>] generic_file_aio_write+0x60/0xae [<ffffffff810b2e82>] do_sync_write+0xe3/0x120 [<ffffffff8104c0f1>] ? autoremove_wake_function+0x0/0x34 [<ffffffff810b18e1>] ? __dentry_open+0x1a5/0x2b8 [<ffffffff810b1a76>] ? dentry_open+0x82/0x89 [<ffffffffa00e693c>] cachefiles_write_page+0x298/0x335 [cachefiles] [<ffffffffa0077147>] fscache_write_op+0x178/0x2c2 [fscache] [<ffffffffa0075656>] fscache_op_execute+0x7a/0xd1 [fscache] [<ffffffff81082093>] slow_work_execute+0x18f/0x2d1 [<ffffffff8108239a>] slow_work_thread+0x1c5/0x308 [<ffffffff8104c0f1>] ? autoremove_wake_function+0x0/0x34 [<ffffffff810821d5>] ? slow_work_thread+0x0/0x308 [<ffffffff8104be91>] kthread+0x7a/0x82 [<ffffffff8100beda>] child_rip+0xa/0x20 [<ffffffff8100b87c>] ? restore_args+0x0/0x30 [<ffffffff8102ef83>] ? tg_shares_up+0x171/0x227 [<ffffffff8104be17>] ? kthread+0x0/0x82 [<ffffffff8100bed0>] ? child_rip+0x0/0x20 In the above backtrace, the following is happening: (1) A page storage operation is being executed by a slow-work thread (fscache_write_op()). (2) FS-Cache farms the operation out to the cache to perform (cachefiles_write_page()). (3) CacheFiles is then calling Ext3 to perform the actual write, using Ext3's standard write (do_sync_write()) under KERNEL_DS directly from the netfs page. (4) However, for Ext3 to perform the write, it must allocate some memory, in particular, it must allocate at least one page cache page into which it can copy the data from the netfs page. (5) Under OOM conditions, the memory allocator can't immediately come up with a page, so it uses vmscan to find something to discard (try_to_free_pages()). (6) vmscan finds a clean netfs page it might be able to discard (possibly the one it's trying to write out). (7) The netfs is called to throw the page away (nfs_release_page()) - but it's called with __GFP_WAIT, so the netfs decides to wait for the store to complete (__fscache_wait_on_page_write()). (8) This blocks a slow-work processing thread - possibly against itself. The system ends up stuck because it can't write out any netfs pages to the cache without allocating more memory. To avoid this, we make FS-Cache cancel some writes that aren't in the middle of actually being performed. This means that some data won't make it into the cache this time. To support this, a new FS-Cache function is added fscache_maybe_release_page() that replaces what the netfs releasepage() functions used to do with respect to the cache. The decisions fscache_maybe_release_page() makes are counted and displayed through /proc/fs/fscache/stats on a line labelled "VmScan". There are four counters provided: "nos=N" - pages that weren't pending storage; "gon=N" - pages that were pending storage when we first looked, but weren't by the time we got the object lock; "bsy=N" - pages that we ignored as they were actively being written when we looked; and "can=N" - pages that we cancelled the storage of. What I'd really like to do is alter the behaviour of the cancellation heuristics, depending on how necessary it is to expel pages. If there are plenty of other pages that aren't waiting to be written to the cache that could be ejected first, then it would be nice to hold up on immediate cancellation of cache writes - but I don't see a way of doing that. Signed-off-by: David Howells <dhowells@redhat.com>
2009-11-19FS-Cache: Handle read request vs lookup, creation or other cache failureDavid Howells
FS-Cache doesn't correctly handle the netfs requesting a read from the cache on an object that failed or was withdrawn by the cache. A trace similar to the following might be seen: CacheFiles: Lookup failed error -105 [exe ] unexpected submission OP165afe [OBJ6cac OBJECT_LC_DYING] [exe ] objstate=OBJECT_LC_DYING [OBJECT_LC_DYING] [exe ] objflags=0 [exe ] objevent=9 [fffffffffffffffb] [exe ] ops=0 inp=0 exc=0 Pid: 6970, comm: exe Not tainted 2.6.32-rc6-cachefs #50 Call Trace: [<ffffffffa0076477>] fscache_submit_op+0x3ff/0x45a [fscache] [<ffffffffa0077997>] __fscache_read_or_alloc_pages+0x187/0x3c4 [fscache] [<ffffffffa00b6480>] ? nfs_readpage_from_fscache_complete+0x0/0x66 [nfs] [<ffffffffa00b6388>] __nfs_readpages_from_fscache+0x7e/0x176 [nfs] [<ffffffff8108e483>] ? __alloc_pages_nodemask+0x11c/0x5cf [<ffffffffa009d796>] nfs_readpages+0x114/0x1d7 [nfs] [<ffffffff81090314>] __do_page_cache_readahead+0x15f/0x1ec [<ffffffff81090228>] ? __do_page_cache_readahead+0x73/0x1ec [<ffffffff810903bd>] ra_submit+0x1c/0x20 [<ffffffff810906bb>] ondemand_readahead+0x227/0x23a [<ffffffff81090762>] page_cache_sync_readahead+0x17/0x19 [<ffffffff8108a99e>] generic_file_aio_read+0x236/0x5a0 [<ffffffffa00937bd>] nfs_file_read+0xe4/0xf3 [nfs] [<ffffffff810b2fa2>] do_sync_read+0xe3/0x120 [<ffffffff81354cc3>] ? _spin_unlock_irq+0x2b/0x31 [<ffffffff8104c0f1>] ? autoremove_wake_function+0x0/0x34 [<ffffffff811848e5>] ? selinux_file_permission+0x5d/0x10f [<ffffffff81352bdb>] ? thread_return+0x3e/0x101 [<ffffffff8117d7b0>] ? security_file_permission+0x11/0x13 [<ffffffff810b3b06>] vfs_read+0xaa/0x16f [<ffffffff81058df0>] ? trace_hardirqs_on_caller+0x10c/0x130 [<ffffffff810b3c84>] sys_read+0x45/0x6c [<ffffffff8100ae2b>] system_call_fastpath+0x16/0x1b The object state might also be OBJECT_DYING or OBJECT_WITHDRAWING. This should be handled by simply rejecting the new operation with ENOBUFS. There's no need to log an error for it. Events of this type now appear in the stats file under Ops:rej. Signed-off-by: David Howells <dhowells@redhat.com>
2009-11-19FS-Cache: Fix lock misorder in fscache_write_op()David Howells
FS-Cache has two structs internally for keeping track of the internal state of a cached file: the fscache_cookie struct, which represents the netfs's state, and fscache_object struct, which represents the cache's state. Each has a pointer that points to the other (when both are in existence), and each has a spinlock for pointer maintenance. Since netfs operations approach these structures from the cookie side, they get the cookie lock first, then the object lock. Cache operations, on the other hand, approach from the object side, and get the object lock first. It is not then permitted for a cache operation to get the cookie lock whilst it is holding the object lock lest deadlock occur; instead, it must do one of two things: (1) increment the cookie usage counter, drop the object lock and then get both locks in order, or (2) simply hold the object lock as certain parts of the cookie may not be altered whilst the object lock is held. It is also not permitted to follow either pointer without holding the lock at the end you start with. To break the pointers between the cookie and the object, both locks must be held. fscache_write_op(), however, violates the locking rules: It attempts to get the cookie lock without (a) checking that the cookie pointer is a valid pointer, and (b) holding the object lock to protect the cookie pointer whilst it follows it. This is so that it can access the pending page store tree without interference from __fscache_write_page(). This is fixed by splitting the cookie lock, such that the page store tracking tree is protected by its own lock, and checking that the cookie pointer is non-NULL before we attempt to follow it whilst holding the object lock. The new lock is subordinate to both the cookie lock and the object lock, and so should be taken after those. Signed-off-by: David Howells <dhowells@redhat.com>
2009-11-19FS-Cache: Permit cache retrieval ops to be interrupted in the initial wait phaseDavid Howells
Permit the operations to retrieve data from the cache or to allocate space in the cache for future writes to be interrupted whilst they're waiting for permission for the operation to proceed. Typically this wait occurs whilst the cache object is being looked up on disk in the background. If an interruption occurs, and the operation has not yet been given the go-ahead to run, the operation is dequeued and cancelled, and control returns to the read operation of the netfs routine with none of the requested pages having been read or in any way marked as known by the cache. This means that the initial wait is done interruptibly rather than uninterruptibly. In addition, extra stats values are made available to show the number of ops cancelled and the number of cache space allocations interrupted. Signed-off-by: David Howells <dhowells@redhat.com>
2009-11-19FS-Cache: Add counters for entry/exit to/from cache operation functionsDavid Howells
Count entries to and exits from cache operation table functions. Maintain these as a single counter that's added to or removed from as appropriate. Signed-off-by: David Howells <dhowells@redhat.com>
2009-11-19FS-Cache: Allow the current state of all objects to be dumpedDavid Howells
Allow the current state of all fscache objects to be dumped by doing: cat /proc/fs/fscache/objects By default, all objects and all fields will be shown. This can be restricted by adding a suitable key to one of the caller's keyrings (such as the session keyring): keyctl add user fscache:objlist "<restrictions>" @s The <restrictions> are: K Show hexdump of object key (don't show if not given) A Show hexdump of object aux data (don't show if not given) And paired restrictions: C Show objects that have a cookie c Show objects that don't have a cookie B Show objects that are busy b Show objects that aren't busy W Show objects that have pending writes w Show objects that don't have pending writes R Show objects that have outstanding reads r Show objects that don't have outstanding reads S Show objects that have slow work queued s Show objects that don't have slow work queued If neither side of a restriction pair is given, then both are implied. For example: keyctl add user fscache:objlist KB @s shows objects that are busy, and lists their object keys, but does not dump their auxiliary data. It also implies "CcWwRrSs", but as 'B' is given, 'b' is not implied. Signed-off-by: David Howells <dhowells@redhat.com>
2009-11-19SLOW_WORK: Allow a requeueable work item to sleep till the thread is neededDavid Howells
Add a function to allow a requeueable work item to sleep till the thread processing it is needed by the slow-work facility to perform other work. Sometimes a work item can't progress immediately, but must wait for the completion of another work item that's currently being processed by another slow-work thread. In some circumstances, the waiting item could instead - theoretically - put itself back on the queue and yield its thread back to the slow-work facility, thus waiting till it gets processing time again before attempting to progress. This would allow other work items processing time on that thread. However, this only works if there is something on the queue for it to queue behind - otherwise it will just get a thread again immediately, and will end up cycling between the queue and the thread, eating up valuable CPU time. So, slow_work_sleep_till_thread_needed() is provided such that an item can put itself on a wait queue that will wake it up when the event it is actually interested in occurs, then call this function in lieu of calling schedule(). This function will then sleep until either the item's event occurs or another work item appears on the queue. If another work item is queued, but the item's event hasn't occurred, then the work item should requeue itself and yield the thread back to the slow-work facility by returning. This can be used by CacheFiles for an object that is being created on one thread to wait for an object being deleted on another thread where there is nothing on the queue for the creation to go and wait behind. As soon as an item appears on the queue that could be given thread time instead, CacheFiles can stick the creating object back on the queue and return to the slow-work facility - assuming the object deletion didn't also complete. Signed-off-by: David Howells <dhowells@redhat.com>
2009-11-19SLOW_WORK: Allow the owner of a work item to determine if it is queued or notDavid Howells
Add a function (slow_work_is_queued()) to permit the owner of a work item to determine if the item is queued or not. The work item is counted as being queued if it is actually on the queue, not just if it is pending. If it is executing and pending, then it is not on the queue, but will rather be put back on the queue when execution finishes. This permits a caller to quickly work out if it may be able to put another, dependent work item on the queue behind it, or whether it will have to wait till that is finished. This can be used by CacheFiles to work out whether the creation a new object can be immediately deferred when it has to wait for an old object to be deleted, or whether a wait must take place. If a wait is necessary, then the slow-work thread can otherwise get blocked, preventing the deletion from taking place. Signed-off-by: David Howells <dhowells@redhat.com>
2009-11-19SLOW_WORK: Allow the work items to be viewed through a /proc fileDavid Howells
Allow the executing and queued work items to be viewed through a /proc file for debugging purposes. The contents look something like the following: THR PID ITEM ADDR FL MARK DESC === ===== ================ == ===== ========== 0 3005 ffff880023f52348 a 952ms FSC: OBJ17d3: LOOK 1 3006 ffff880024e33668 2 160ms FSC: OBJ17e5 OP60d3b: Write1/Store fl=2 2 3165 ffff8800296dd180 a 424ms FSC: OBJ17e4: LOOK 3 4089 ffff8800262c8d78 a 212ms FSC: OBJ17ea: CRTN 4 4090 ffff88002792bed8 2 388ms FSC: OBJ17e8 OP60d36: Write1/Store fl=2 5 4092 ffff88002a0ef308 2 388ms FSC: OBJ17e7 OP60d2e: Write1/Store fl=2 6 4094 ffff88002abaf4b8 2 132ms FSC: OBJ17e2 OP60d4e: Write1/Store fl=2 7 4095 ffff88002bb188e0 a 388ms FSC: OBJ17e9: CRTN vsq - ffff880023d99668 1 308ms FSC: OBJ17e0 OP60f91: Write1/EnQ fl=2 vsq - ffff8800295d1740 1 212ms FSC: OBJ16be OP4d4b6: Write1/EnQ fl=2 vsq - ffff880025ba3308 1 160ms FSC: OBJ179a OP58dec: Write1/EnQ fl=2 vsq - ffff880024ec83e0 1 160ms FSC: OBJ17ae OP599f2: Write1/EnQ fl=2 vsq - ffff880026618e00 1 160ms FSC: OBJ17e6 OP60d33: Write1/EnQ fl=2 vsq - ffff880025a2a4b8 1 132ms FSC: OBJ16a2 OP4d583: Write1/EnQ fl=2 vsq - ffff880023cbe6d8 9 212ms FSC: OBJ17eb: LOOK vsq - ffff880024d37590 9 212ms FSC: OBJ17ec: LOOK vsq - ffff880027746cb0 9 212ms FSC: OBJ17ed: LOOK vsq - ffff880024d37ae8 9 212ms FSC: OBJ17ee: LOOK vsq - ffff880024d37cb0 9 212ms FSC: OBJ17ef: LOOK vsq - ffff880025036550 9 212ms FSC: OBJ17f0: LOOK vsq - ffff8800250368e0 9 212ms FSC: OBJ17f1: LOOK vsq - ffff880025036aa8 9 212ms FSC: OBJ17f2: LOOK In the 'THR' column, executing items show the thread they're occupying and queued threads indicate which queue they're on. 'PID' shows the process ID of a slow-work thread that's executing something. 'FL' shows the work item flags. 'MARK' indicates how long since an item was queued or began executing. Lastly, the 'DESC' column permits the owner of an item to give some information. Signed-off-by: David Howells <dhowells@redhat.com>
2009-11-19SLOW_WORK: Add delayed_slow_work supportJens Axboe
This adds support for starting slow work with a delay, similar to the functionality we have for workqueues. Signed-off-by: Jens Axboe <jens.axboe@oracle.com> Signed-off-by: David Howells <dhowells@redhat.com>
2009-11-19SLOW_WORK: Add support for cancellation of slow workJens Axboe
Add support for cancellation of queued slow work and delayed slow work items. The cancellation functions will wait for items that are pending or undergoing execution to be discarded by the slow work facility. Attempting to enqueue work that is in the process of being cancelled will result in ECANCELED. Signed-off-by: Jens Axboe <jens.axboe@oracle.com> Signed-off-by: David Howells <dhowells@redhat.com>
2009-11-19SLOW_WORK: Make slow_work_ops ->get_ref/->put_ref optionalJens Axboe
Make the ability for the slow-work facility to take references on a work item optional as not everyone requires this. Even the internal slow-work stubs them out, so those can be got rid of too. Signed-off-by: Jens Axboe <jens.axboe@oracle.com> Signed-off-by: David Howells <dhowells@redhat.com>
2009-11-19SLOW_WORK: Wait for outstanding work items belonging to a module to clearDavid Howells
Wait for outstanding slow work items belonging to a module to clear when unregistering that module as a user of the facility. This prevents the put_ref code of a work item from being taken away before it returns. Signed-off-by: David Howells <dhowells@redhat.com>
2009-11-17Merge branch 'hostprogs-wmissing-prototypes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/josh/linux-misc * 'hostprogs-wmissing-prototypes' of git://git.kernel.org/pub/scm/linux/kernel/git/josh/linux-misc: Makefile: Add -Wmising-prototypes to HOSTCFLAGS oss: Mark loadhex static in hex2hex.c dtc: Mark various internal functions static dtc: Set "noinput" in the lexer to avoid an unused function drm: radeon: Mark several functions static in mkregtable arch/sparc/boot/*.c: Mark various internal functions static arch/powerpc/boot/addRamDisk.c: Mark several internal functions static arch/alpha/boot/tools/objstrip.c: Mark "usage" static Documentation/vm/page-types.c: Declare checked_open static genksyms: Mark is_reserved_word static kconfig: Mark various internal functions static kconfig: Make zconf.y work with current bison