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2010-03-10Merge commit 'v2.6.32.9' into android-2.6.32Arve Hjønnevåg
2010-02-09KVM: allow userspace to adjust kvmclock offsetGlauber Costa
(cherry picked from afbcf7ab8d1bc8c2d04792f6d9e786e0adeb328d) When we migrate a kvm guest that uses pvclock between two hosts, we may suffer a large skew. This is because there can be significant differences between the monotonic clock of the hosts involved. When a new host with a much larger monotonic time starts running the guest, the view of time will be significantly impacted. Situation is much worse when we do the opposite, and migrate to a host with a smaller monotonic clock. This proposed ioctl will allow userspace to inform us what is the monotonic clock value in the source host, so we can keep the time skew short, and more importantly, never goes backwards. Userspace may also need to trigger the current data, since from the first migration onwards, it won't be reflected by a simple call to clock_gettime() anymore. [marcelo: future-proof abi with a flags field] [jan: fix KVM_GET_CLOCK by clearing flags field instead of checking it] Signed-off-by: Glauber Costa <glommer@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-02-03[docs] android: Add android config documentation to boot framework.Mike Chan
Signed-off-by: Mike Chan <mike@android.com>
2010-01-28V4L/DVB (13680b): DocBook/media: create links for included sourcesBen Hutchings
commit 5bf583473813530c1bf82051a35fac8d5045f4f7 upstream. If docs are being built in a separate directory, xmlto and xsltproc can't find included sources. Make links back to the source directory. I would much prefer to have xmlto and xsltproc look in the source directory for included entities but couldn't see how to do that. This needs to be solved in some way for 2.6.32, even if this patch isn't the right way to do it. Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Cc: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-01-28V4L/DVB (13680a): DocBook/media: copy images after building HTMLBen Hutchings
commit 49b14650ba5bf80234cb1984fd8396aff03430ce upstream. The rule for %.html removes the output directory, so there is no point in copying images before building HTML. Documentation/DocBook/Makefile | 10 +++++----- Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com> Cc: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-01-28V4L/DVB (13168): Add support for Asus Europa Hybrid DVB-T card (SAA7134 ↵Danny Wood
SubVendor ID: 0x1043 Device ID: 0x4847) commit e3c6e1aaa5db7822524f5b1355960fd732910068 upstream. 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> Cc: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-01-06ext4: Update documentation to correct the inode_readahead_blks option nameFang Wenqi
commit 6d3b82f2d31f22085e5711b28dddcb9fb3d97a25 upstream. Per commit 240799cd, the option name for readahead should be inode_readahead_blks, not inode_readahead. Signed-off-by: Fang Wenqi <antonf@turbolinux.com.cn> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-12-18netfilter: xtables: document minimal required versionJan Engelhardt
commit 7a92263705435d046d37a0990d0edfcb517f7ad3 upstream. For both .33 and .32-stable. Signed-off-by: Jan Engelhardt <jengelh@medozas.de> Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-12-18V4L/DVB (13116): gspca - ov519: Webcam 041e:4067 added.Rafal Milecki
commit 518c8df77c21b7d1690dd8b96eb0e54c4ec1c9c1 upstream. 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> Cc: Surbhi Palande <surbhi.palande@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-12-18USB: usb-storage: add BAD_SENSE flagAlan Stern
commit a0bb108112a872c0b0c4b3ef4974f95fb75b155d upstream. This patch (as1311) fixes a problem in usb-storage: Some devices are pretty broken when it comes to reporting sense data. The information they send back indicates that they have more than 18 bytes of sense data available, but when the system asks for more than 18 they fail or hang. The symptom is that probing fails with multiple resets. The patch adds a new BAD_SENSE flag to indicate that usb-storage should never ask for more than 18 bytes of sense data. The flag can be set in an unusual_devs entry or via the "quirks=" module parameter, and it is set automatically whenever a REQUEST SENSE command for more than 18 bytes fails or times out. An unusual_devs entry is added for the Agfa photo frame, which uses a Prolific chip having this bug. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Tested-by: Daniel Kukula <daniel.kuku@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-12-14ext4: make "norecovery" an alias for "noload"Eric Sandeen
(cherry picked from commit e3bb52ae2bb9573e84c17b8e3560378d13a5c798) Users on the linux-ext4 list recently complained about differences across filesystems w.r.t. how to mount without a journal replay. In the discussion it was noted that xfs's "norecovery" option is perhaps more descriptively accurate than "noload," so let's make that an alias for ext4. Also show this status in /proc/mounts Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-12-14ext4: make trim/discard optional (and off by default)Eric Sandeen
(cherry picked from commit 5328e635315734d42080de9a5a1ee87bf4cae0a4) It is anticipated that when sb_issue_discard starts doing real work on trim-capable devices, we may see issues. Make this mount-time optional, and default it to off until we know that things are working out OK. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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
2009-11-15Documentation/vm/page-types.c: Declare checked_open staticJosh Triplett
Nothing outside of Documentation/vm/page-types.c references checked_open. Signed-off-by: Josh Triplett <josh@joshtriplett.org>
2009-11-13ocfs2: Refresh documentationSunil Mushran
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com> Signed-off-by: Joel Becker <joel.becker@oracle.com>
2009-11-09Merge branch 'i2c-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging * 'i2c-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging: i2c: Add an interface to lock/unlock an I2C bus segment i2c-piix4: Modify code name SB900 to Hudson-2
2009-11-07i2c-piix4: Modify code name SB900 to Hudson-2Crane Cai
Change SB900 to its formal code name Hudson-2. Signed-off-by: Crane Cai <crane.cai@amd.com> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2009-11-05Merge branches 'misc', 'eeepc-laptop' and 'bugzilla-14445' into releaseLen Brown
2009-11-05thermal: sysfs-api.txt - document passive attribute for thermal zonesFrans Pop
Signed-off-by: Frans Pop <elendil@planet.nl> Acked-by: Zhang Rui <rui.zhang@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Len Brown <len.brown@intel.com>
2009-11-05thermal: sysfs-api.txt - reformat for improved readabilityFrans Pop
The document currently uses large indentations which make the text too wide for easy readability. Also improve general consistency. Signed-off-by: Frans Pop <elendil@planet.nl> Acked-by: Zhang Rui <rui.zhang@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Len Brown <len.brown@intel.com>
2009-11-02Revert "ext4: Remove journal_checksum mount option and enable it by default"Linus Torvalds
This reverts commit d0646f7b636d067d715fab52a2ba9c6f0f46b0d7, as requested by Eric Sandeen. It can basically cause an ext4 filesystem to miss recovery (and thus get mounted with errors) if the journal checksum does not match. Quoth Eric: "My hand-wavy hunch about what is happening is that we're finding a bad checksum on the last partially-written transaction, which is not surprising, but if we have a wrapped log and we're doing the initial scan for head/tail, and we abort scanning on that bad checksum, then we are essentially running an unrecovered filesystem. But that's hand-wavy and I need to go look at the code. We lived without journal checksums on by default until now, and at this point they're doing more harm than good, so we should revert the default-changing commit until we can fix it and do some good power-fail testing with the fixes in place." See http://bugzilla.kernel.org/show_bug.cgi?id=14354 for all the gory details. Requested-by: Eric Sandeen <sandeen@redhat.com> Cc: Theodore Tso <tytso@mit.edu> Cc: Alexey Fisher <bug-track@fisher-privat.net> Cc: Maxim Levitsky <maximlevitsky@gmail.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: Mathias Burén <mathias.buren@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-11-02Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6: ALSA: hda - Don't check invalid HP pin ALSA: dummy - Fix descriptions of pcm_substreams parameter ALSA: pcmcia: use dynamic debug infrastructure, deprecate CS_CHECK (sound) ALSA: hda: Use quirk mask for Dell Inspiron Mini9/Vostro A90 using ALC268 sound: via82xx: deactivate DXS controls of inactive streams ALSA: snd-usb-caiaq: Bump version number to 1.3.20 ALSA: snd-usb-caiaq: Lock on stream start/unpause ALSA: snd-usb-caiaq: Missing lock around use of buffer positions ALSA: sound/parisc: Move dereference after NULL test ALSA: sound: Move dereference after NULL test and drop unnecessary NULL tests ALSA: hda_intel: Add the Linux device ID for NVIDIA HDA controller ALSA: pcsp - Fix nforce workaround ALSA: SND_CS5535AUDIO: Remove the X86 platform dependency ASoC: Amstrad Delta: add info about the line discipline requirement to Kconfig help text ASoC: Fix possible codec_dai->ops NULL pointer problems ALSA: hda - Fix capture source checks for ALC662/663 codecs ASoC: Serialize access to dapm_power_widgets()
2009-11-02Merge branch 'tracing-fixes-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: tracing: Remove cpu arg from the rb_time_stamp() function tracing: Fix comment typo and documentation example tracing: Fix trace_seq_printf() return value tracing: Update *ppos instead of filp->f_pos
2009-11-02ALSA: dummy - Fix descriptions of pcm_substreams parameterTakashi Iwai
Now up to 128 substreams are supported. Reported-by: Adrian Bridgett <adrian@smop.co.uk> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2009-10-30Documentation: ABI: /sys/devices/system/cpu/cpu#/nodeAlex Chiang
Describe NUMA node symlink created for CPUs when CONFIG_NUMA is set. Cc: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Alex Chiang <achiang@hp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-10-30Documentation: ABI: /sys/devices/system/cpu/cpuidle/Alex Chiang
Document cpuidle sysfs attributes by reading code, Documentation/cpuidle/, and git logs. Cc: Venki Pallipadi <venkatesh.pallipadi@intel.com> Cc: Len Brown <lenb@kernel.org> Signed-off-by: Alex Chiang <achiang@hp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-10-30Documentation: ABI: /sys/devices/system/cpu/sched_[mc|smt]_power_savingsAlex Chiang
Document sched_[mc|smt]_power_savings by reading existing code and git logs. Cc: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Alex Chiang <achiang@hp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-10-30Documentation: ABI: /sys/devices/system/cpu/cpu#/ topology filesAlex Chiang
Add brief descriptions for the following sysfs files: /sys/devices/system/cpu/cpu#/topology/core_id /sys/devices/system/cpu/cpu#/topology/core_siblings /sys/devices/system/cpu/cpu#/topology/core_siblings_list /sys/devices/system/cpu/cpu#/topology/physical_package_id /sys/devices/system/cpu/cpu#/topology/thread_siblings /sys/devices/system/cpu/cpu#/topology/thread_siblings_list The descriptions in Documentation/cputopology.txt weren't very informative, so I attempted a better description based on code reading and hopeful guessing. Updated Documentation/cputopology.txt with the better descriptions and fixed some style issues. Cc: Mike Travis <travis@sgi.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Alex Chiang <achiang@hp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-10-30Documentation: ABI: /sys/devices/system/cpu/ topology filesAlex Chiang
Add brief descriptions for the following sysfs files: /sys/devices/system/cpu/kernel_max /sys/devices/system/cpu/offline /sys/devices/system/cpu/online /sys/devices/system/cpu/possible /sys/devices/system/cpu/present Excerpted the relevant information from Documentation/cputopology.txt and pointed back to cputopology.txt as the authoritative source of information. Cc: Mike Travis <travis@sgi.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Alex Chiang <achiang@hp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-10-30Documentation: ABI: document /sys/devices/system/cpu/Alex Chiang
This interface has been around for a long time, but hasn't been officially documented. Document the top level sysfs directory for CPU attributes. Signed-off-by: Alex Chiang <achiang@hp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-10-30Documentation: ABI: rename sysfs-devices-cache_disable properlyAlex Chiang
Rename sysfs-devices-cache_disable to sysfs-devices-system-cpu, in order to keep a stricter correlation between a sysfs directory and its documentation. Reported-by: David Rientjes <rientjes@google.com> Signed-off-by: Alex Chiang <achiang@hp.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>