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2012-06-01cpu: introduce clear_tasks_mm_cpumask() helperAnton Vorontsov
Many architectures clear tasks' mm_cpumask like this: read_lock(&tasklist_lock); for_each_process(p) { if (p->mm) cpumask_clear_cpu(cpu, mm_cpumask(p->mm)); } read_unlock(&tasklist_lock); Depending on the context, the code above may have several problems, such as: 1. Working with task->mm w/o getting mm or grabing the task lock is dangerous as ->mm might disappear (exit_mm() assigns NULL under task_lock(), so tasklist lock is not enough). 2. Checking for process->mm is not enough because process' main thread may exit or detach its mm via use_mm(), but other threads may still have a valid mm. This patch implements a small helper function that does things correctly, i.e.: 1. We take the task's lock while whe handle its mm (we can't use get_task_mm()/mmput() pair as mmput() might sleep); 2. To catch exited main thread case, we use find_lock_task_mm(), which walks up all threads and returns an appropriate task (with task lock held). Also, Per Peter Zijlstra's idea, now we don't grab tasklist_lock in the new helper, instead we take the rcu read lock. We can do this because the function is called after the cpu is taken down and marked offline, so no new tasks will get this cpu set in their mm mask. Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Cc: Richard Weinberger <richard@nod.at> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Mike Frysinger <vapier@gentoo.org> Cc: Paul Mundt <lethal@linux-sh.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-06-01cred: remove task_is_dead() from __task_cred() validationOleg Nesterov
Commit 8f92054e7ca1 ("CRED: Fix __task_cred()'s lockdep check and banner comment"): add the following validation condition: task->exit_state >= 0 to permit the access if the target task is dead and therefore unable to change its own credentials. OK, but afaics currently this can only help wait_task_zombie() which calls __task_cred() without rcu lock. Remove this validation and change wait_task_zombie() to use task_uid() instead. This means we do rcu_read_lock() only to shut up the lockdep, but we already do the same in, say, wait_task_stopped(). task_is_dead() should die, task->exit_state != 0 means that this task has passed exit_notify(), only do_wait-like code paths should use this. Unfortunately, we can't kill task_is_dead() right now, it has already acquired buggy users in drivers/staging. The fix already exists. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: David Howells <dhowells@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: James Morris <jmorris@namei.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-06-01kmod: move call_usermodehelper_fns() to .c file and unexport all it's helpersBoaz Harrosh
If we move call_usermodehelper_fns() to kmod.c file and EXPORT_SYMBOL it we can avoid exporting all it's helper functions: call_usermodehelper_setup call_usermodehelper_setfns call_usermodehelper_exec And make all of them static to kmod.c Since the optimizer will see all these as a single call site it will inline them inside call_usermodehelper_fns(). So we loose the call to _fns but gain 3 calls to the helpers. (Not that it matters) Signed-off-by: Boaz Harrosh <bharrosh@panasas.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-06-01kmod: unexport call_usermodehelper_freeinfo()Boaz Harrosh
call_usermodehelper_freeinfo() is not used outside of kmod.c. So unexport it, and make it static to kmod.c Signed-off-by: Boaz Harrosh <bharrosh@panasas.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-06-01fat: introduce special inode for managing the FSINFO blockArtem Bityutskiy
This is patchset makes fatfs stop using the VFS '->write_super()' method for writing out the FSINFO block. The final goal is to get rid of the 'sync_supers()' kernel thread. This kernel thread wakes up every 5 seconds (by default) and calls '->write_super()' for all mounted file-systems. And the bad thing is that this is done even if all the superblocks are clean. Moreover, some file-systems do not even need this end they do not register the '->write_super()' method at all (e.g., btrfs). So 'sync_supers()' most often just generates useless wake-ups and wastes power. I am trying to make all file-systems independent of '->write_super()' and plan to remove 'sync_supers()' and '->write_super' completely once there are no more users. The '->write_supers()' method is mostly used by baroque file-systems like hfs, udf, etc. Modern file-systems like btrfs and xfs do not use it. This justifies removing this stuff from VFS completely and make every FS self-manage own superblock. Tested with xfstests. This patch: Preparation for further changes. It introduces a special inode ('fsinfo_inode') in FAT file-system which we'll later use for managing the FSINFO block. Note, this there is already one special inode ('fat_inode') which is used for managing the FAT tables. Introduce new 'MSDOS_FSINFO_INO' constant for this special inode. It is safe to do because FAT file-system does not store inode numbers on the media but generates them run-time. I've also cleaned up the comment to existing 'MSDOS_ROOT_INO' constant, while on it. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-06-01vsprintf: further optimize decimal conversionDenys Vlasenko
Previous code was using optimizations which were developed to work well even on narrow-word CPUs (by today's standards). But Linux runs only on 32-bit and wider CPUs. We can use that. First: using 32x32->64 multiply and trivial 32-bit shift, we can correctly divide by 10 much larger numbers, and thus we can print groups of 9 digits instead of groups of 5 digits. Next: there are two algorithms to print larger numbers. One is generic: divide by 1000000000 and repeatedly print groups of (up to) 9 digits. It's conceptually simple, but requires an (unsigned long long) / 1000000000 division. Second algorithm splits 64-bit unsigned long long into 16-bit chunks, manipulates them cleverly and generates groups of 4 decimal digits. It so happens that it does NOT require long long division. If long is > 32 bits, division of 64-bit values is relatively easy, and we will use the first algorithm. If long long is > 64 bits (strange architecture with VERY large long long), second algorithm can't be used, and we again use the first one. Else (if long is 32 bits and long long is 64 bits) we use second one. And third: there is a simple optimization which takes fast path not only for zero as was done before, but for all one-digit numbers. In all tested cases new code is faster than old one, in many cases by 30%, in few cases by more than 50% (for example, on x86-32, conversion of 12345678). Code growth is ~0 in 32-bit case and ~130 bytes in 64-bit case. This patch is based upon an original from Michal Nazarewicz. [akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Michal Nazarewicz <mina86@mina86.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> Cc: Douglas W Jones <jones@cs.uiowa.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-06-01introduce SIZE_MAXXi Wang
ULONG_MAX is often used to check for integer overflow when calculating allocation size. While ULONG_MAX happens to work on most systems, there is no guarantee that `size_t' must be the same size as `long'. This patch introduces SIZE_MAX, the maximum value of `size_t', to improve portability and readability for allocation size validation. Signed-off-by: Xi Wang <xi.wang@gmail.com> Acked-by: Alex Elder <elder@dreamhost.com> Cc: David Airlie <airlied@linux.ie> Cc: Pekka Enberg <penberg@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-06-01nfsd4: move rq_flavor into svc_credJ. Bruce Fields
Move the rq_flavor into struct svc_cred, and use it in setclientid and exchange_id comparisons as well. Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2012-06-01nfsd4: move principal name into svc_credJ. Bruce Fields
Instead of keeping the principal name associated with a request in a structure that's private to auth_gss and using an accessor function, move it to svc_cred. Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2012-06-01SUNRPC: new svc_bind() routine introducedStanislav Kinsbursky
This new routine is responsible for service registration in a specified network context. The idea is to separate service creation from per-net operations. Note also: since registering service with svc_bind() can fail, the service will be destroyed and during destruction it will try to unregister itself from rpcbind. In this case unregistration has to be skipped. Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2012-05-31net/mlx4_core: Fix number of EQs used in ICM initialisationMarcel Apfelbaum
In SRIOV mode, the number of EQs used when computing the total ICM size was incorrect. To fix this, we do the following: 1. We add a new structure to mlx4_dev, mlx4_phys_caps, to contain physical HCA capabilities. The PPF uses the phys capabilities when it computes things like ICM size. The dev_caps structure will then contain the paravirtualized values, making bookkeeping much easier in SRIOV mode. We add a structure rather than a single parameter because there will be other fields in the phys_caps. The first field we add to the mlx4_phys_caps structure is num_phys_eqs. 2. In INIT_HCA, when running in SRIOV mode, the "log_num_eqs" parameter passed to the FW is the number of EQs per VF/PF; each function (PF or VF) has this number of EQs available. However, the total number of EQs which must be allowed for in the ICM is (1 << log_num_eqs) * (#VFs + #PFs). Rather than compute this quantity, we allocate ICM space for 1024 EQs (which is the device maximum number of EQs, and which is the value we place in the mlx4_phys_caps structure). For INIT_HCA, however, we use the per-function number of EQs as described above. Signed-off-by: Marcel Apfelbaum <marcela@dev.mellanox.co.il> Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il> Reviewed-by: Or Gerlitz <ogerlitz@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-05-31Merge tag 'for-v3.5' of git://git.infradead.org/battery-2.6Linus Torvalds
Pull battery updates from Anton Vorontsov: "A bunch of fixes for v3.5, nothing extraordinary." * tag 'for-v3.5' of git://git.infradead.org/battery-2.6: (27 commits) smb347-charger: Include missing <linux/err.h> smb347-charger: Clean up battery attributes max17042_battery: Add support for max17047/50 chip sbs-battery.c: Capacity attr = remaining relative capacity isp1704_charger: Use after free on probe error ds2781_battery: Use DS2781_PARAM_EEPROM_SIZE and DS2781_USER_EEPROM_SIZE power_supply: Fix a typo in BATTERY_DS2781 Kconfig entry charger-manager: Provide cm_notify_event function for in-kernel use charger-manager: Poll battery health in normal state smb347-charger: Convert to regmap API smb347-charger: Move IRQ enabling to the end of probe smb347-charger: Rename few functions to match better what they are doing smb347-charger: Convert to use module_i2c_driver() smb347_charger: Cleanup power supply registration code in probe ab8500: Clean up probe routines ab8500_fg: Harden platform data check ab8500_btemp: Harden platform data check ab8500_charger: Harden platform data check MAINTAINERS: Fix 'F' entry for the power supply class max17042_battery: Handle irq request failure case ...
2012-05-31Merge git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull two small kvm fixes from Avi Kivity: "A build fix for non-kvm archs and a transparent hugepage refcount bugfix on hosts with 4M pages." * git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: Export asm-generic/kvm_para.h KVM: MMU: fix huge page adapted on non-PAE host
2012-05-31Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsiLinus Torvalds
Pull final round of SCSI updates from James Bottomley: "This is primarily another round of driver updates (bnx2fc, qla2xxx, qla4xxx) including the target mode driver for qla2xxx. We've also got a couple of regression fixes (async scanning, broken this merge window and a fix to a long standing break in the scsi_wait_scan module)." * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (45 commits) [SCSI] fix scsi_wait_scan [SCSI] fix async probe regression [SCSI] be2iscsi: fix dma free size mismatch regression [SCSI] qla4xxx: Update driver version to 5.02.00-k17 [SCSI] qla4xxx: Capture minidump for ISP82XX on firmware failure [SCSI] qla4xxx: Add change_queue_depth API support [SCSI] qla4xxx: Fix clear ddb mbx command failure issue. [SCSI] qla4xxx: Fix kernel panic during discovery logout. [SCSI] qla4xxx: Correct early completion of pending mbox. [SCSI] fcoe, bnx2fc, libfcoe: SW FCoE and bnx2fc use FCoE Syfs [SCSI] libfcoe: Add fcoe_sysfs [SCSI] bnx2fc: Allocate fcoe_ctlr with bnx2fc_interface, not as a member [SCSI] fcoe: Allocate fcoe_ctlr with fcoe_interface, not as a member [SCSI] Fix dm-multipath starvation when scsi host is busy [SCSI] ufs: fix potential NULL pointer dereferencing error in ufshcd_prove. [SCSI] qla2xxx: don't free pool that wasn't allocated [SCSI] mptfusion: unlock on error in mpt_config() [SCSI] tcm_qla2xxx: Add >= 24xx series fabric module for target-core [SCSI] qla2xxx: Add LLD target-mode infrastructure for >= 24xx series [SCSI] Revert "qla2xxx: During loopdown perform Diagnostic loopback." ...
2012-05-31NFS: Ensure that setattr and getattr wait for O_DIRECT write completionTrond Myklebust
Use the same mechanism as the block devices are using, but move the helper functions from fs/direct-io.c into fs/inode.c to remove the dependency on CONFIG_BLOCK. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Fred Isaman <iisaman@netapp.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-31Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds
Pull networking changes from David S. Miller: 1) Fix IPSEC header length calculation for transport mode in ESP. The issue is whether to do the calculation before or after alignment. Fix from Benjamin Poirier. 2) Fix regression in IPV6 IPSEC fragment length calculations, from Gao Feng. This is another transport vs tunnel mode issue. 3) Handle AF_UNSPEC connect()s properly in L2TP to avoid OOPSes. Fix from James Chapman. 4) Fix USB ASIX driver's reception of full sized VLAN packets, from Eric Dumazet. 5) Allow drop monitor (and, more generically, all generic netlink protocols) to be automatically loaded as a module. From Neil Horman. Fix up trivial conflict in Documentation/feature-removal-schedule.txt due to new entries added next to each other at the end. As usual. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (38 commits) net/smsc911x: Repair broken failure paths virtio-net: remove useless disable on freeze netdevice: Update netif_dbg for CONFIG_DYNAMIC_DEBUG drop_monitor: Add module alias to enable automatic module loading genetlink: Build a generic netlink family module alias net: add MODULE_ALIAS_NET_PF_PROTO_NAME r6040: Do a Proper deinit at errorpath and also when driver unloads (calling r6040_remove_one) r6040: disable pci device if the subsequent calls (after pci_enable_device) fails skb: avoid unnecessary reallocations in __skb_cow net: sh_eth: fix the rxdesc pointer when rx descriptor empty happens asix: allow full size 8021Q frames to be received rds_rdma: don't assume infiniband device is PCI l2tp: fix oops in L2TP IP sockets for connect() AF_UNSPEC case mac80211: fix ADDBA declined after suspend with wowlan wlcore: fix undefined symbols when CONFIG_PM is not defined mac80211: fix flag check for QoS NOACK frames ath9k_hw: apply internal regulator settings on AR933x ath9k_hw: update AR933x initvals to fix issues with high power devices ath9k: fix a use-after-free-bug when ath_tx_setup_buffer() fails ath9k: stop rx dma before stopping tx ...
2012-05-31split ->file_mmap() into ->mmap_addr()/->mmap_file()Al Viro
... i.e. file-dependent and address-dependent checks. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-31split cap_mmap_addr() out of cap_file_mmap()Al Viro
... switch callers. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-31fsnotify: handle subfiles' perm eventsNaohiro Aota
Recently I'm working on fanotify and found the following strange behaviors. I wrote a program to set fanotify_mark on "/tmp/block" and FAN_DENY all events notified. fanotify_mask = FAN_ALL_EVENTS | FAN_ALL_PERM_EVENTS | FAN_EVENT_ON_CHILD: $ cd /tmp/block; cat foo cat: foo: Operation not permitted Operation on the file is blocked as expected. But, fanotify_mask = FAN_ALL_PERM_EVENTS | FAN_EVENT_ON_CHILD: $ cd /tmp/block; cat foo aaa It's not blocked anymore. This is confusing behavior. Also reading commit "fsnotify: call fsnotify_parent in perm events", it seems like fsnotify should handle subfiles' perm events as well as the other notify events. With this patch, regardless of FAN_ALL_EVENTS set or not: $ cd /tmp/block; cat foo cat: foo: Operation not permitted Operation on the file is now blocked properly. FS_OPEN_PERM and FS_ACCESS_PERM are not listed on FS_EVENTS_POSS_ON_CHILD. Due to fsnotify_inode_watches_children() check, if you only specify only these events as fsnotify_mask, you don't get subfiles' perm events notified. This patch add the events to FS_EVENTS_POSS_ON_CHILD to get them notified even if only these events are specified to fsnotify_mask. Signed-off-by: Naohiro Aota <naota@elisp.net> Cc: Eric Paris <eparis@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-31bury __kernel_nlink_t, make internal nlink_t consistentAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-30netdevice: Update netif_dbg for CONFIG_DYNAMIC_DEBUGJoe Perches
Make netif_dbg use dynamic debugging whenever CONFIG_DYNAMIC_DEBUG is enabled. commit b558c96ffa53 ("dynamic_debug: make dynamic-debug supersede DEBUG ccflag") missed updating the netif_dbg variant. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-05-30Merge git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-clientLinus Torvalds
Pull ceph updates from Sage Weil: "There are some updates and cleanups to the CRUSH placement code, a bug fix with incremental maps, several cleanups and fixes from Josh Durgin in the RBD block device code, a series of cleanups and bug fixes from Alex Elder in the messenger code, and some miscellaneous bounds checking and gfp cleanups/fixes." Fix up trivial conflicts in net/ceph/{messenger.c,osdmap.c} due to the networking people preferring "unsigned int" over just "unsigned". * git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: (45 commits) libceph: fix pg_temp updates libceph: avoid unregistering osd request when not registered ceph: add auth buf in prepare_write_connect() ceph: rename prepare_connect_authorizer() ceph: return pointer from prepare_connect_authorizer() ceph: use info returned by get_authorizer ceph: have get_authorizer methods return pointers ceph: ensure auth ops are defined before use ceph: messenger: reduce args to create_authorizer ceph: define ceph_auth_handshake type ceph: messenger: check return from get_authorizer ceph: messenger: rework prepare_connect_authorizer() ceph: messenger: check prepare_write_connect() result ceph: don't set WRITE_PENDING too early ceph: drop msgr argument from prepare_write_connect() ceph: messenger: send banner in process_connect() ceph: messenger: reset connection kvec caller libceph: don't reset kvec in prepare_write_banner() ceph: ignore preferred_osd field ceph: fully initialize new layout ...
2012-05-30Merge branch 'i2c-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging Pull i2c updates from Jean Delvare. * 'i2c-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging: i2c: Split I2C_M_NOSTART support out of I2C_FUNC_PROTOCOL_MANGLING i2c-dev: Add support for I2C_M_RECV_LEN
2012-05-30Merge git://www.linux-watchdog.org/linux-watchdogLinus Torvalds
Pull second set of watchdog updates from Wim Van Sebroeck: "This changeset contains following changes: * Add support for multiple watchdog devices. We use dynamically allocated device id's for this. * Add locking into the generic watchdog infrastructure. * Add support for dynamically allocated watchdog_device structs so that we can deal with devices that get unbound. * convert following drivers to the generic watchdog framework: sch5627, sch5636 and sp805_wdt. * Add DA9052/53 PMIC watchdog support * Fix printk format warnings for iTCO_wdt.c" * git://www.linux-watchdog.org/linux-watchdog: watchdog: iTCO_wdt.c: fix printk format warnings watchdog: sp805_wdt: Add clk_{un}prepare support watchdog: sp805_wdt: convert to watchdog core hwmon/sch56xx: Depend on watchdog for watchdog core functions watchdog: sch56xx-common: set correct bits in register() Watchdog: DA9052/53 PMIC watchdog support watchdog: sch56xx-common: Add proper ref-counting of watchdog data watchdog: sch56xx: Remove unnecessary checks for register changes watchdog: sch56xx: Use watchdog core watchdog: Add support for dynamically allocated watchdog_device structs watchdog: Add Locking support watchdog: watchdog_dev: Rewrite wrapper code watchdog: use dev_ functions watchdog: create all the proper device files watchdog: Add a flag to indicate the watchdog doesn't reboot things watchdog: Add multiple device support watchdog: watchdog_core.h: make functions extern watchdog: correct the name of the watchdog_core inlude file watchdog: Add watchdog_active() routine watchdog: watchdog_dev: include private header to pickup global symbol prototypes
2012-05-30Merge branch 'for-3.5/drivers' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block driver updates from Jens Axboe: "Here are the driver related changes for 3.5. It contains: - The floppy changes from Jiri. Jiri is now also marked as the maintainer of floppy.c, I shall be publically branding his forehead with red hot iron at the next opportune moment. - A batch of drbd updates and fixes from the linbit crew, as well as fixes from others. - Two small fixes for xen-blkfront courtesy of Jan." * 'for-3.5/drivers' of git://git.kernel.dk/linux-block: (70 commits) floppy: take over maintainership floppy: remove floppy-specific O_EXCL handling floppy: convert to delayed work and single-thread wq xen-blkfront: module exit handling adjustments xen-blkfront: properly name all devices drbd: grammar fix in log message drbd: check MODULE for THIS_MODULE drbd: Restore the request restart logic drbd: introduce a bio_set to allocate housekeeping bios from drbd: remove unused define drbd: bm_page_async_io: properly initialize page->private drbd: use the newly introduced page pool for bitmap IO drbd: add page pool to be used for meta data IO drbd: allow bitmap to change during writeout from resync_finished drbd: fix race between drbdadm invalidate/verify and finishing resync drbd: fix resend/resubmit of frozen IO drbd: Ensure that data_size is not 0 before using data_size-1 as index drbd: Delay/reject other state changes while establishing a connection drbd: move put_ldev from __req_mod() to the endio callback drbd: fix WRITE_ACKED_BY_PEER_AND_SIS to not set RQ_NET_DONE ...
2012-05-30Merge branch 'for-3.5/core' of git://git.kernel.dk/linux-blockLinus Torvalds
Merge block/IO core bits from Jens Axboe: "This is a bit bigger on the core side than usual, but that is purely because we decided to hold off on parts of Tejun's submission on 3.4 to give it a bit more time to simmer. As a consequence, it's seen a long cycle in for-next. It contains: - Bug fix from Dan, wrong locking type. - Relax splice gifting restriction from Eric. - A ton of updates from Tejun, primarily for blkcg. This improves the code a lot, making the API nicer and cleaner, and also includes fixes for how we handle and tie policies and re-activate on switches. The changes also include generic bug fixes. - A simple fix from Vivek, along with a fix for doing proper delayed allocation of the blkcg stats." Fix up annoying conflict just due to different merge resolution in Documentation/feature-removal-schedule.txt * 'for-3.5/core' of git://git.kernel.dk/linux-block: (92 commits) blkcg: tg_stats_alloc_lock is an irq lock vmsplice: relax alignement requirements for SPLICE_F_GIFT blkcg: use radix tree to index blkgs from blkcg blkcg: fix blkcg->css ref leak in __blkg_lookup_create() block: fix elvpriv allocation failure handling block: collapse blk_alloc_request() into get_request() blkcg: collapse blkcg_policy_ops into blkcg_policy blkcg: embed struct blkg_policy_data in policy specific data blkcg: mass rename of blkcg API blkcg: style cleanups for blk-cgroup.h blkcg: remove blkio_group->path[] blkcg: blkg_rwstat_read() was missing inline blkcg: shoot down blkgs if all policies are deactivated blkcg: drop stuff unused after per-queue policy activation update blkcg: implement per-queue policy activation blkcg: add request_queue->root_blkg blkcg: make request_queue bypassing on allocation blkcg: make sure blkg_lookup() returns %NULL if @q is bypassing blkcg: make blkg_conf_prep() take @pol and return with queue lock held blkcg: remove static policy ID enums ...
2012-05-30Merge tag 'iommu-updates-v3.5' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu Pull IOMMU updates from Joerg Roedel: "Not much stuff this time. The only change to the IOMMU core code is the addition of a handle to the fault handling code. A few updates to the AMD IOMMU driver to work around new errata. The other patches are mostly fixes and enhancements to the existing ARM IOMMU drivers and documentation updates. A new IOMMU driver for the Exynos platform was also underway but got merged via the Samsung tree and is not part of this tree." * tag 'iommu-updates-v3.5' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: Documentation: kernel-parameters.txt Add amd_iommu_dump iommu/core: pass a user-provided token to fault handlers iommu/tegra: gart: Fix register offset correctly iommu: OMAP: device detach on domain destroy iommu: tegra/gart: Add device tree support iommu: tegra/gart: use correct gart_device iommu/tegra: smmu: Print device name correctly iommu/amd: Add workaround for event log erratum iommu/amd: Check for the right TLP prefix bit dma-debug: release free_entries_lock before saving stack trace
2012-05-30i2c: Split I2C_M_NOSTART support out of I2C_FUNC_PROTOCOL_MANGLINGMark Brown
Since there are uses for I2C_M_NOSTART which are much more sensible and standard than most of the protocol mangling functionality (the main one being gather writes to devices where something like a register address needs to be inserted before a block of data) create a new I2C_FUNC_NOSTART for this feature and update all the users to use it. Also strengthen the disrecommendation of the protocol mangling while we're at it. In the case of regmap-i2c we remove the requirement for mangling as I2C_M_NOSTART is the only mangling feature which is being used. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Wolfram Sang <w.sang@pengutronix.de> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-05-30watchdog: Add support for dynamically allocated watchdog_device structsHans de Goede
If a driver's watchdog_device struct is part of a dynamically allocated struct (which it often will be), merely locking the module is not enough, even with a drivers module locked, the driver can be unbound from the device, examples: 1) The root user can unbind it through sysfd 2) The i2c bus master driver being unloaded for an i2c watchdog I will gladly admit that these are corner cases, but we still need to handle them correctly. The fix for this consists of 2 parts: 1) Add ref / unref operations, so that the driver can refcount the struct holding the watchdog_device struct and delay freeing it until any open filehandles referring to it are closed 2) Most driver operations will do IO on the device and the driver should not do any IO on the device after it has been unbound. Rather then letting each driver deal with this internally, it is better to ensure at the watchdog core level that no operations (other then unref) will get called after the driver has called watchdog_unregister_device(). This actually is the bulk of this patch. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2012-05-30watchdog: Add Locking supportHans de Goede
This patch fixes some potential multithreading issues, despite only allowing one process to open the /dev/watchdog device, we can still get called multiple times at the same time, since a program could be using thread, or could share the fd after a fork. This causes 2 potential problems: 1) watchdog_start / open do an unlocked test_n_set / test_n_clear, if these 2 race, the watchdog could be stopped while the active bit indicates it is running or visa versa. 2) Most watchdog_dev drivers probably assume that only one watchdog-op will get called at a time, this is not necessary true atm. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2012-05-30watchdog: create all the proper device filesAlan Cox
Create the watchdog class and it's associated devices. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2012-05-30watchdog: Add a flag to indicate the watchdog doesn't reboot thingsAlan Cox
Some watchdogs merely trigger external alarms and controls. In a managed environment this is very useful but we want drivers to be able to figure out which is which now multiple dogs can be loaded. Thus add an ALARMONLY feature flag. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2012-05-30watchdog: Add multiple device supportAlan Cox
We keep the old /dev/watchdog interface file for the first watchdog via miscdev. This is basically a cut and paste of the relevant interface code from the rtc driver layer tweaked for watchdog. Revised to fix problems noted by Hans de Goede Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2012-05-30watchdog: Add watchdog_active() routineViresh Kumar
Some watchdog may need to check if watchdog is ACTIVE or not, for example in their suspend/resume hooks. This patch adds this routine and changes the core drivers to use it. Signed-off-by: Viresh Kumar <viresh.kumar@st.com> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2012-05-30brlocks/lglocks: turn into functionsAndi Kleen
lglocks and brlocks are currently generated with some complicated macros in lglock.h. But there's no reason to not just use common utility functions and put all the data into a common data structure. Since there are at least two users it makes sense to share this code in a library. This is also easier maintainable than a macro forest. This will also make it later possible to dynamically allocate lglocks and also use them in modules (this would both still need some additional, but now straightforward, code) [akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Andi Kleen <ak@linux.intel.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-30lglock: remove online variants of lockRusty Russell
Optimizing the slow paths adds a lot of complexity. If you need to grab every lock often, you have other problems. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Acked-by: Nick Piggin <npiggin@kernel.dk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-30->encode_fh() API changeAl Viro
pass inode + parent's inode or NULL instead of dentry + bool saying whether we want the parent or not. NOTE: that needs ceph fix folded in. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-30genetlink: Build a generic netlink family module aliasNeil Horman
Generic netlink searches for -type- formatted aliases when requesting a module to fulfill a protocol request (i.e. net-pf-16-proto-16-type-<x>, where x is a type value). However generic netlink protocols have no well defined type numbers, they have string names. Modify genl_ctrl_getfamily to request an alias in the format net-pf-16-proto-16-family-<x> instead, where x is a generic string, and add a macro that builds on the previously added MODULE_ALIAS_NET_PF_PROTO_NAME macro to allow modules to specifify those generic strings. Note, l2tp previously hacked together an net-pf-16-proto-16-type-l2tp alias using the MODULE_ALIAS macro, with these updates we can convert that to use the PROTO_NAME macro. Signed-off-by: Neil Horman <nhorman@tuxdriver.com> CC: Eric Dumazet <eric.dumazet@gmail.com> CC: James Chapman <jchapman@katalix.com> CC: David Miller <davem@davemloft.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-05-30net: add MODULE_ALIAS_NET_PF_PROTO_NAMENeil Horman
The MODULE_ALAIS_NET_PF macro set is missing a variant that allows for the appending of an arbitrary string to the net-pf-<x>-proto-<y> base. while MODULE_ALIAS_NET_PF_PROTO_NAME_TYPE allows an appending of a numerical type, we need to be able to append a generic string to support generic netlink families that have neither a fix numberical protocol nor type number Signed-off-by: Neil Horman <nhorman@tuxdriver.com> CC: Eric Dumazet <eric.dumazet@gmail.com> CC: David Miller <davem@davemloft.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-05-30Merge git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-edacLinus Torvalds
Pull EDAC internal API changes from Mauro Carvalho Chehab: "This changeset is the first part of a series of patches that fixes the EDAC sybsystem. On this set, it changes the Kernel EDAC API in order to properly represent the Intel i3/i5/i7, Xeon 3xxx/5xxx/7xxx, and Intel E5-xxxx memory controllers. The EDAC core used to assume that: - the DRAM chip select pin is directly accessed by the memory controller - when multiple channels are used, they're all filled with the same type of memory. None of the above premises is true on Intel memory controllers since 2002, when RAMBUS and FB-DIMMs were introduced, and Advanced Memory Buffer or by some similar technologies hides the direct access to the DRAM pins. So, the existing drivers for those chipsets had to lie to the EDAC core, in general telling that just one channel is filled. That produces some hard to understand error messages like: EDAC MC0: CE row 3, channel 0, label "DIMM1": 1 Unknown error(s): memory read error on FATAL area : cpu=0 Err=0008:00c2 (ch=2), addr = 0xad1f73480 => socket=0, Channel=0(mask=2), rank=1 The location information there (row3 channel 0) is completely bogus: it has no physical meaning, and are just some random values that the driver uses to talk with the EDAC core. The error actually happened at CPU socket 0, channel 0, slot 1, but this is not reported anywhere, as the EDAC core doesn't know anything about the memory layout. So, only advanced users that know how the EDAC driver works and that tests their systems to see how DIMMs are mapped can actually benefit for such error logs. This patch series fixes the error report logic, in order to allow the EDAC to expose the memory architecture used by them to the EDAC core. So, as the EDAC core now understands how the memory is organized, it can provide an useful report: EDAC MC0: CE memory read error on DIMM1 (channel:0 slot:1 page:0x364b1b offset:0x600 grain:32 syndrome:0x0 - count:1 area:DRAM err_code:0001:0090 socket:0 channel_mask:1 rank:4) The location of the DIMM where the error happened is reported by "MC0" (cpu socket #0), at "channel:0 slot:1" location, and matches the physical location of the DIMM. There are two remaining issues not covered by this patch series: - The EDAC sysfs API will still report bogus values. So, userspace tools like edac-utils will still use the bogus data; - Add a new tracepoint-based way to get the binary information about the errors. Those are on a second series of patches (also at -next), but will probably miss the train for 3.5, due to the slow review process." Fix up trivial conflict (due to spelling correction of removed code) in drivers/edac/edac_device.c * git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-edac: (42 commits) i7core: fix ranks information at the per-channel struct i5000: Fix the fatal error handling i5100_edac: Fix a warning when compiled with 32 bits i82975x_edac: Test nr_pages earlier to save a few CPU cycles e752x_edac: provide more info about how DIMMS/ranks are mapped i5000_edac: Fix the logic that retrieves memory information i5400_edac: improve debug messages to better represent the filled memory edac: Cleanup the logs for i7core and sb edac drivers edac: Initialize the dimm label with the known information edac: Remove the legacy EDAC ABI x38_edac: convert driver to use the new edac ABI tile_edac: convert driver to use the new edac ABI sb_edac: convert driver to use the new edac ABI r82600_edac: convert driver to use the new edac ABI ppc4xx_edac: convert driver to use the new edac ABI pasemi_edac: convert driver to use the new edac ABI mv64x60_edac: convert driver to use the new edac ABI mpc85xx_edac: convert driver to use the new edac ABI i82975x_edac: convert driver to use the new edac ABI i82875p_edac: convert driver to use the new edac ABI ...
2012-05-30Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linusLinus Torvalds
Pull MIPS updates from Ralf Baechle: "The whole series has been sitting in -next for quite a while with no complaints. The last change to the series was before the weekend the removal of an SPI patch which Grant - even though previously acked by himself - appeared to raise objections. So I removed it until the situation is clarified. Other than that all the patches have the acks from their respective maintainers, all MIPS and x86 defconfigs are building fine and I'm not aware of any problems introduced by this series. Among the key features for this patch series is a sizable patchset for Lantiq which among other things introduces support for Lantiq's flagship product, the FALCON SOC. It also means that the opensource developers behind this patchset have overtaken Lantiq's competing inhouse development team that was working behind closed doors. Less noteworthy the ath79 patchset which adds support for a few more chip variants, cleanups and fixes. Finally the usual dose of tweaking of generic code." Fix up trivial conflicts in arch/mips/lantiq/xway/gpio_{ebu,stp}.c where printk spelling fixes clashed with file move and eventual removal of the printk. * 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (81 commits) MIPS: lantiq: remove orphaned code MIPS: Remove all -Wall and almost all -Werror usage from arch/mips. MIPS: lantiq: implement support for FALCON soc MTD: MIPS: lantiq: verify that the NOR interface is available on falcon soc MTD: MIPS: lantiq: implement OF support watchdog: MIPS: lantiq: implement OF support and minor fixes SERIAL: MIPS: lantiq: implement OF support GPIO: MIPS: lantiq: convert gpio-stp-xway to OF GPIO: MIPS: lantiq: convert gpio-mm-lantiq to OF and of_mm_gpio GPIO: MIPS: lantiq: move gpio-stp and gpio-ebu to the subsystem folder MIPS: pci: convert lantiq driver to OF MIPS: lantiq: convert dma to platform driver MIPS: lantiq: implement support for clkdev api MIPS: lantiq: drop ltq_gpio_request() and gpio_to_irq() OF: MIPS: lantiq: implement irq_domain support OF: MIPS: lantiq: implement OF support MIPS: lantiq: drop mips_machine support OF: PCI: const usage needed by MIPS MIPS: Cavium: Remove smp_reserve_lock. MIPS: Move cache setup to setup_arch(). ...
2012-05-29rtc: ds1307: add trickle charger supportWolfram Sang
Some DS13XX devices have "trickle chargers". Its configuration register is at different locations, the setup is the same, though. Since the configuration is board specific, introduce a platform_data to this driver. Tested with a DS1339 on a custom board. Signed-off-by: Wolfram Sang <w.sang@pengutronix.de> Cc: Alessandro Zummo <alessandro.zummo@towertech.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-29rtc: add ioctl to get/clear battery low voltage statusAlexander Stein
Currently there is no generic way to get the RTC battery status within an application. So add an ioctl to read the status bit. The idea is that the bit is set once a low voltage is detected. It stays there until it is reset using the RTC_VL_CLR ioctl. Signed-off-by: Alexander Stein <alexander.stein@systec-electronic.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-29vsprintf: fix %ps on non symbols when using kallsymsStephen Boyd
Using %ps in a printk format will sometimes fail silently and print the empty string if the address passed in does not match a symbol that kallsyms knows about. But using %pS will fall back to printing the full address if kallsyms can't find the symbol. Make %ps act the same as %pS by falling back to printing the address. While we're here also make %ps print the module that a symbol comes from so that it matches what %pS already does. Take this simple function for example (in a module): static void test_printk(void) { int test; pr_info("with pS: %pS\n", &test); pr_info("with ps: %ps\n", &test); } Before this patch: with pS: 0xdff7df44 with ps: After this patch: with pS: 0xdff7df44 with ps: 0xdff7df44 Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-29include/linux/led-lm3530.h: comment correction about the range of brightnessKim, Milo
max brightness is 127, so the range of brt_val should be from 0 to 127 Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Cc: Shreshtha Kumar SAHU <shreshthakumar.sahu@stericsson.com> Cc: Richard Purdie <rpurdie@rpsys.net> Cc: Bryan Wu <bryan.wu@canonical.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-29leds: add new field to led_classdev struct to save activation stateShuah Khan
Add a new field to led_classdev to save activattion state after activate routine is successful. This saved state is used in deactivate routine to do cleanup such as removing device files, and free memory allocated during activation. Currently trigger_data not being null is used for this purpose. Existing triggers will need changes to use this new field. Signed-off-by: Shuah Khan <shuahkhan@gmail.com> Cc: Richard Purdie <rpurdie@rpsys.net> Cc: Bryan Wu <bryan.wu@canonical.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-29drivers/video/backlight/apple_bl.c: include header for exported symbol ↵H Hartley Sweeten
prototypes Include the header to pickup the exported symbol prototype. Quiets the sparse warning: warning: symbol 'apple_bl_register' was not declared. Should it be static? warning: symbol 'apple_bl_unregister' was not declared. Should it be static? [akpm@linux-foundation.org: fix resulting build error] Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Richard Purdie <rpurdie@rpsys.net> Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-29lcd: add callbacks for early fb event blank supportInki Dae
This patchset adds early fb blank feature that a callback of lcd panel driver is called prior to specific fb driver's one. In the case of MIPI-DSI based video mode LCD Panel, for lcd power off, the power off commands should be transferred to lcd panel with display and mipi-dsi controller enabled because the commands is set to lcd panel at vsync porch period. and in opposite case, the callback of fb driver should be called prior to lcd panel driver's one because of same issue. Also if fb_blank mode is changed to FB_BLANK_POWERDOWN then display controller would be off(clock disable) but lcd panel would be still on. at this time, you could see some issue like sparkling on lcd panel because video clock to be delivered to ldi module of lcd panel was disabled. this issue could occurs for all lcd panels. The callback order is as the following: at fb_blank function of fbmem.c -> fb_notifier_call_chain(FB_EARLY_EVENT_BLANK) -> lcd panel driver's early_set_power() -> info->fbops->fb_blank() -> spcefic fb driver's fb_blank() -> fb_notifier_call_chain(FB_EVENT_BLANK) -> lcd panel driver's set_power() -> fb_notifier_call_chain(FB_R_EARLY_EVENT_BLANK) if info->fops->fb_blank() was failed. fb_notifier_call_chain(FB_R_EARLY_EVENT_BLANK) would be called to revert the effects of previous FB_EARLY_EVENT_BLANK call. and note that if early_set_power() of lcd_ops is NULL then early fb blank callback would be ignored. This patch: Add early_set_power and r_early_set_power callbacks. early_set_power callback is called prior to fb_blank() of fbmem.c and r_early_set_power callback is called if fb_blank() was failed to revert the effects of the early_set_power call of lcd panel driver. Signed-off-by: Inki Dae <inki.dae@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Cc: Lars-Peter Clausen <lars@metafoo.de> Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de> Cc: Richard Purdie <rpurdie@rpsys.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-29fbdev: add events for early fb event supportInki Dae
Add FB_EARLY_EVENT_BLANK and FB_R_EARLY_EVENT_BLANK event mode supports. first, fb_notifier_call_chain() is called with FB_EARLY_EVENT_BLANK and fb_blank() of specific fb driver is called and then fb_notifier_call_chain() is called with FB_EVENT_BLANK again at fb_blank(). and if fb_blank() was failed then fb_nitifier_call_chain() would be called with FB_R_EARLY_EVENT_BLANK to revert the previous effects. Signed-off-by: Inki Dae <inki.dae@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Cc: Lars-Peter Clausen <lars@metafoo.de> Acked-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de> Cc: Richard Purdie <rpurdie@rpsys.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-29memcg: decrement static keys at real destroy timeGlauber Costa
We call the destroy function when a cgroup starts to be removed, such as by a rmdir event. However, because of our reference counters, some objects are still inflight. Right now, we are decrementing the static_keys at destroy() time, meaning that if we get rid of the last static_key reference, some objects will still have charges, but the code to properly uncharge them won't be run. This becomes a problem specially if it is ever enabled again, because now new charges will be added to the staled charges making keeping it pretty much impossible. We just need to be careful with the static branch activation: since there is no particular preferred order of their activation, we need to make sure that we only start using it after all call sites are active. This is achieved by having a per-memcg flag that is only updated after static_key_slow_inc() returns. At this time, we are sure all sites are active. This is made per-memcg, not global, for a reason: it also has the effect of making socket accounting more consistent. The first memcg to be limited will trigger static_key() activation, therefore, accounting. But all the others will then be accounted no matter what. After this patch, only limited memcgs will have its sockets accounted. [akpm@linux-foundation.org: move enum sock_flag_bits into sock.h, document enum sock_flag_bits, convert memcg_proto_active() and memcg_proto_activated() to test_bit(), redo tcp_update_limit() comment to 80 cols] Signed-off-by: Glauber Costa <glommer@parallels.com> Cc: Tejun Heo <tj@kernel.org> Cc: Li Zefan <lizefan@huawei.com> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.cz> Acked-by: David Miller <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>