From f08f5a0add20834d3f3d876dfe08005a5df656db Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Thu, 16 Dec 2010 17:11:58 +0100 Subject: PM / Runtime: Fix pm_runtime_suspended() There are some situations (e.g. in __pm_generic_call()), where pm_runtime_suspended() is used to decide whether or not to execute a device's (system) ->suspend() callback. The callback is not executed if pm_runtime_suspended() returns true, but it does so for devices that don't even support runtime PM, because the power.disable_depth device field is ignored by it. This leads to problems (i.e. devices are not suspened when they should), so rework pm_runtime_suspended() so that it returns false if the device's power.disable_depth field is different from zero. Signed-off-by: Rafael J. Wysocki Cc: stable@kernel.org --- Documentation/power/runtime_pm.txt | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'Documentation') diff --git a/Documentation/power/runtime_pm.txt b/Documentation/power/runtime_pm.txt index 489e9bacd16..41cc7b30d7d 100644 --- a/Documentation/power/runtime_pm.txt +++ b/Documentation/power/runtime_pm.txt @@ -379,8 +379,8 @@ drivers/base/power/runtime.c and include/linux/pm_runtime.h: zero) bool pm_runtime_suspended(struct device *dev); - - return true if the device's runtime PM status is 'suspended', or false - otherwise + - return true if the device's runtime PM status is 'suspended' and its + 'power.disable_depth' field is equal to zero, or false otherwise void pm_runtime_allow(struct device *dev); - set the power.runtime_auto flag for the device and decrease its usage -- cgit v1.2.3 From c0f5ac5426f7fd82b23dd5c6a1e633b290294a08 Mon Sep 17 00:00:00 2001 From: Bjorn Helgaas Date: Thu, 16 Dec 2010 10:38:41 -0700 Subject: Revert "resources: support allocating space within a region from the top down" This reverts commit e7f8567db9a7f6b3151b0b275e245c1cef0d9c70. Acked-by: H. Peter Anvin Signed-off-by: Bjorn Helgaas Signed-off-by: Jesse Barnes --- Documentation/kernel-parameters.txt | 5 ----- 1 file changed, 5 deletions(-) (limited to 'Documentation') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index cdd2a6e8a3b..8b61c936099 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -2175,11 +2175,6 @@ and is between 256 and 4096 characters. It is defined in the file reset_devices [KNL] Force drivers to reset the underlying device during initialization. - resource_alloc_from_bottom - Allocate new resources from the beginning of available - space, not the end. If you need to use this, please - report a bug. - resume= [SWSUSP] Specify the partition device for software suspend -- cgit v1.2.3 From 29687512c0b084957112cc2c0743ce34cd0d5055 Mon Sep 17 00:00:00 2001 From: James Bottomley Date: Thu, 16 Dec 2010 09:22:24 -0500 Subject: [SCSI] fix up documentation for change in ->queuecommand to lockless calling The current doc still says we call it with the host lock held, which is going to cause confusion. Signed-off-by: James Bottomley --- Documentation/scsi/scsi_mid_low_api.txt | 59 +++++++++++++++++---------------- 1 file changed, 31 insertions(+), 28 deletions(-) (limited to 'Documentation') diff --git a/Documentation/scsi/scsi_mid_low_api.txt b/Documentation/scsi/scsi_mid_low_api.txt index 570ef2b3d79..df322c10346 100644 --- a/Documentation/scsi/scsi_mid_low_api.txt +++ b/Documentation/scsi/scsi_mid_low_api.txt @@ -1044,9 +1044,9 @@ Details: /** - * queuecommand - queue scsi command, invoke 'done' on completion + * queuecommand - queue scsi command, invoke scp->scsi_done on completion + * @shost: pointer to the scsi host object * @scp: pointer to scsi command object - * @done: function pointer to be invoked on completion * * Returns 0 on success. * @@ -1074,42 +1074,45 @@ Details: * * Other types of errors that are detected immediately may be * flagged by setting scp->result to an appropriate value, - * invoking the 'done' callback, and then returning 0 from this - * function. If the command is not performed immediately (and the - * LLD is starting (or will start) the given command) then this - * function should place 0 in scp->result and return 0. + * invoking the scp->scsi_done callback, and then returning 0 + * from this function. If the command is not performed + * immediately (and the LLD is starting (or will start) the given + * command) then this function should place 0 in scp->result and + * return 0. * * Command ownership. If the driver returns zero, it owns the - * command and must take responsibility for ensuring the 'done' - * callback is executed. Note: the driver may call done before - * returning zero, but after it has called done, it may not - * return any value other than zero. If the driver makes a - * non-zero return, it must not execute the command's done - * callback at any time. - * - * Locks: struct Scsi_Host::host_lock held on entry (with "irqsave") - * and is expected to be held on return. + * command and must take responsibility for ensuring the + * scp->scsi_done callback is executed. Note: the driver may + * call scp->scsi_done before returning zero, but after it has + * called scp->scsi_done, it may not return any value other than + * zero. If the driver makes a non-zero return, it must not + * execute the command's scsi_done callback at any time. + * + * Locks: up to and including 2.6.36, struct Scsi_Host::host_lock + * held on entry (with "irqsave") and is expected to be + * held on return. From 2.6.37 onwards, queuecommand is + * called without any locks held. * * Calling context: in interrupt (soft irq) or process context * - * Notes: This function should be relatively fast. Normally it will - * not wait for IO to complete. Hence the 'done' callback is invoked - * (often directly from an interrupt service routine) some time after - * this function has returned. In some cases (e.g. pseudo adapter - * drivers that manufacture the response to a SCSI INQUIRY) - * the 'done' callback may be invoked before this function returns. - * If the 'done' callback is not invoked within a certain period - * the SCSI mid level will commence error processing. - * If a status of CHECK CONDITION is placed in "result" when the - * 'done' callback is invoked, then the LLD driver should - * perform autosense and fill in the struct scsi_cmnd::sense_buffer + * Notes: This function should be relatively fast. Normally it + * will not wait for IO to complete. Hence the scp->scsi_done + * callback is invoked (often directly from an interrupt service + * routine) some time after this function has returned. In some + * cases (e.g. pseudo adapter drivers that manufacture the + * response to a SCSI INQUIRY) the scp->scsi_done callback may be + * invoked before this function returns. If the scp->scsi_done + * callback is not invoked within a certain period the SCSI mid + * level will commence error processing. If a status of CHECK + * CONDITION is placed in "result" when the scp->scsi_done + * callback is invoked, then the LLD driver should perform + * autosense and fill in the struct scsi_cmnd::sense_buffer * array. The scsi_cmnd::sense_buffer array is zeroed prior to * the mid level queuing a command to an LLD. * * Defined in: LLD **/ - int queuecommand(struct scsi_cmnd * scp, - void (*done)(struct scsi_cmnd *)) + int queuecommand(struct Scsi_Host *shost, struct scsi_cmnd * scp) /** -- cgit v1.2.3 From 7a2d19bced51af31d2c9ff55219400ed0a6c012f Mon Sep 17 00:00:00 2001 From: Mel Gorman Date: Tue, 21 Dec 2010 17:24:18 -0800 Subject: mm: vmscan: tracepoint: account for scanned pages similarly for both ftrace and vmstat When correlating ftrace results with /proc/vmstat, I noticed that the reporting scripts value for "pages scanned" differed significantly. Both values were "right" depending on how you look at it. The difference is due to vmstat only counting scanning of the inactive list towards pages scanned. The analysis script for the tracepoint counts active and inactive list yielding a far higher value than vmstat. The resulting scanning/reclaim ratio looks much worse. The tracepoint is ok but this patch updates the reporting script so that the report values for scanned are similar to vmstat. Signed-off-by: Mel Gorman Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/trace/postprocess/trace-vmscan-postprocess.pl | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/trace/postprocess/trace-vmscan-postprocess.pl b/Documentation/trace/postprocess/trace-vmscan-postprocess.pl index b3e73ddb156..12cecc83cd9 100644 --- a/Documentation/trace/postprocess/trace-vmscan-postprocess.pl +++ b/Documentation/trace/postprocess/trace-vmscan-postprocess.pl @@ -373,9 +373,18 @@ EVENT_PROCESS: print " $regex_lru_isolate/o\n"; next; } + my $isolate_mode = $1; my $nr_scanned = $4; my $nr_contig_dirty = $7; - $perprocesspid{$process_pid}->{HIGH_NR_SCANNED} += $nr_scanned; + + # To closer match vmstat scanning statistics, only count isolate_both + # and isolate_inactive as scanning. isolate_active is rotation + # isolate_inactive == 0 + # isolate_active == 1 + # isolate_both == 2 + if ($isolate_mode != 1) { + $perprocesspid{$process_pid}->{HIGH_NR_SCANNED} += $nr_scanned; + } $perprocesspid{$process_pid}->{HIGH_NR_CONTIG_DIRTY} += $nr_contig_dirty; } elsif ($tracepoint eq "mm_vmscan_lru_shrink_inactive") { $details = $5; -- cgit v1.2.3 From 4be2c95d1f7706ca0e74499f2bd118e1cee19669 Mon Sep 17 00:00:00 2001 From: Jeff Mahoney Date: Tue, 21 Dec 2010 17:24:30 -0800 Subject: taskstats: pad taskstats netlink response for aligment issues on ia64 The taskstats structure is internally aligned on 8 byte boundaries but the layout of the aggregrate reply, with two NLA headers and the pid (each 4 bytes), actually force the entire structure to be unaligned. This causes the kernel to issue unaligned access warnings on some architectures like ia64. Unfortunately, some software out there doesn't properly unroll the NLA packet and assumes that the start of the taskstats structure will always be 20 bytes from the start of the netlink payload. Aligning the start of the taskstats structure breaks this software, which we don't want. So, for now the alignment only happens on architectures that require it and those users will have to update to fixed versions of those packages. Space is reserved in the packet only when needed. This ifdef should be removed in several years e.g. 2012 once we can be confident that fixed versions are installed on most systems. We add the padding before the aggregate since the aggregate is already a defined type. Commit 85893120 ("delayacct: align to 8 byte boundary on 64-bit systems") previously addressed the alignment issues by padding out the pid field. This was supposed to be a compatible change but the circumstances described above mean that it wasn't. This patch backs out that change, since it was a hack, and introduces a new NULL attribute type to provide the padding. Padding the response with 4 bytes avoids allocating an aligned taskstats structure and copying it back. Since the structure weighs in at 328 bytes, it's too big to do it on the stack. Signed-off-by: Jeff Mahoney Reported-by: Brian Rogers Cc: Jeff Mahoney Cc: Guillaume Chazarain Cc: Balbir Singh Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/accounting/getdelays.c | 1 + 1 file changed, 1 insertion(+) (limited to 'Documentation') diff --git a/Documentation/accounting/getdelays.c b/Documentation/accounting/getdelays.c index a2976a6de03..e9c77788a39 100644 --- a/Documentation/accounting/getdelays.c +++ b/Documentation/accounting/getdelays.c @@ -516,6 +516,7 @@ int main(int argc, char *argv[]) default: fprintf(stderr, "Unknown nla_type %d\n", na->nla_type); + case TASKSTATS_TYPE_NULL: break; } na = (struct nlattr *) (GENLMSG_DATA(&msg) + len); -- cgit v1.2.3 From b83be6f20a0e468f715b14225c9f897538dfe5ad Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 16 Dec 2010 12:04:54 +0100 Subject: update Documentation/filesystems/Locking Mostly inspired by all the recent BKL removal changes, but a lot of older updates also weren't properly recorded. Signed-off-by: Christoph Hellwig Signed-off-by: Linus Torvalds --- Documentation/filesystems/Locking | 214 ++++++++++++++++++-------------------- 1 file changed, 102 insertions(+), 112 deletions(-) (limited to 'Documentation') diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking index b6426f15b4a..7686e768449 100644 --- a/Documentation/filesystems/Locking +++ b/Documentation/filesystems/Locking @@ -18,7 +18,6 @@ prototypes: char *(*d_dname)((struct dentry *dentry, char *buffer, int buflen); locking rules: - none have BKL dcache_lock rename_lock ->d_lock may block d_revalidate: no no no yes d_hash no no no yes @@ -42,18 +41,23 @@ ata *); int (*rename) (struct inode *, struct dentry *, struct inode *, struct dentry *); int (*readlink) (struct dentry *, char __user *,int); - int (*follow_link) (struct dentry *, struct nameidata *); + void * (*follow_link) (struct dentry *, struct nameidata *); + void (*put_link) (struct dentry *, struct nameidata *, void *); void (*truncate) (struct inode *); int (*permission) (struct inode *, int, struct nameidata *); + int (*check_acl)(struct inode *, int); int (*setattr) (struct dentry *, struct iattr *); int (*getattr) (struct vfsmount *, struct dentry *, struct kstat *); int (*setxattr) (struct dentry *, const char *,const void *,size_t,int); ssize_t (*getxattr) (struct dentry *, const char *, void *, size_t); ssize_t (*listxattr) (struct dentry *, char *, size_t); int (*removexattr) (struct dentry *, const char *); + void (*truncate_range)(struct inode *, loff_t, loff_t); + long (*fallocate)(struct inode *inode, int mode, loff_t offset, loff_t len); + int (*fiemap)(struct inode *, struct fiemap_extent_info *, u64 start, u64 len); locking rules: - all may block, none have BKL + all may block i_mutex(inode) lookup: yes create: yes @@ -66,19 +70,24 @@ rmdir: yes (both) (see below) rename: yes (all) (see below) readlink: no follow_link: no +put_link: no truncate: yes (see below) setattr: yes permission: no +check_acl: no getattr: no setxattr: yes getxattr: no listxattr: no removexattr: yes +truncate_range: yes +fallocate: no +fiemap: no Additionally, ->rmdir(), ->unlink() and ->rename() have ->i_mutex on victim. cross-directory ->rename() has (per-superblock) ->s_vfs_rename_sem. ->truncate() is never called directly - it's a callback, not a -method. It's called by vmtruncate() - library function normally used by +method. It's called by vmtruncate() - deprecated library function used by ->setattr(). Locking information above applies to that call (i.e. is inherited from ->setattr() - vmtruncate() is used when ATTR_SIZE had been passed). @@ -91,7 +100,7 @@ prototypes: struct inode *(*alloc_inode)(struct super_block *sb); void (*destroy_inode)(struct inode *); void (*dirty_inode) (struct inode *); - int (*write_inode) (struct inode *, int); + int (*write_inode) (struct inode *, struct writeback_control *wbc); int (*drop_inode) (struct inode *); void (*evict_inode) (struct inode *); void (*put_super) (struct super_block *); @@ -105,10 +114,11 @@ prototypes: int (*show_options)(struct seq_file *, struct vfsmount *); ssize_t (*quota_read)(struct super_block *, int, char *, size_t, loff_t); ssize_t (*quota_write)(struct super_block *, int, const char *, size_t, loff_t); + int (*bdev_try_to_free_page)(struct super_block*, struct page*, gfp_t); + int (*trim_fs) (struct super_block *, struct fstrim_range *); locking rules: All may block [not true, see below] - None have BKL s_umount alloc_inode: destroy_inode: @@ -127,6 +137,8 @@ umount_begin: no show_options: no (namespace_sem) quota_read: no (see below) quota_write: no (see below) +bdev_try_to_free_page: no (see below) +trim_fs: no ->statfs() has s_umount (shared) when called by ustat(2) (native or compat), but that's an accident of bad API; s_umount is used to pin @@ -139,19 +151,25 @@ be the only ones operating on the quota file by the quota code (via dqio_sem) (unless an admin really wants to screw up something and writes to quota files with quotas on). For other details about locking see also dquot_operations section. +->bdev_try_to_free_page is called from the ->releasepage handler of +the block device inode. See there for more details. --------------------------- file_system_type --------------------------- prototypes: int (*get_sb) (struct file_system_type *, int, const char *, void *, struct vfsmount *); + struct dentry *(*mount) (struct file_system_type *, int, + const char *, void *); void (*kill_sb) (struct super_block *); locking rules: - may block BKL -get_sb yes no -kill_sb yes no + may block +get_sb yes +mount yes +kill_sb yes ->get_sb() returns error or 0 with locked superblock attached to the vfsmount (exclusive on ->s_umount). +->mount() returns ERR_PTR or the root dentry. ->kill_sb() takes a write-locked superblock, does all shutdown work on it, unlocks and drops the reference. @@ -176,27 +194,35 @@ prototypes: void (*freepage)(struct page *); int (*direct_IO)(int, struct kiocb *, const struct iovec *iov, loff_t offset, unsigned long nr_segs); - int (*launder_page) (struct page *); + int (*get_xip_mem)(struct address_space *, pgoff_t, int, void **, + unsigned long *); + int (*migratepage)(struct address_space *, struct page *, struct page *); + int (*launder_page)(struct page *); + int (*is_partially_uptodate)(struct page *, read_descriptor_t *, unsigned long); + int (*error_remove_page)(struct address_space *, struct page *); locking rules: All except set_page_dirty and freepage may block - BKL PageLocked(page) i_mutex -writepage: no yes, unlocks (see below) -readpage: no yes, unlocks -sync_page: no maybe -writepages: no -set_page_dirty no no -readpages: no -write_begin: no locks the page yes -write_end: no yes, unlocks yes -perform_write: no n/a yes -bmap: no -invalidatepage: no yes -releasepage: no yes -freepage: no yes -direct_IO: no -launder_page: no yes + PageLocked(page) i_mutex +writepage: yes, unlocks (see below) +readpage: yes, unlocks +sync_page: maybe +writepages: +set_page_dirty no +readpages: +write_begin: locks the page yes +write_end: yes, unlocks yes +bmap: +invalidatepage: yes +releasepage: yes +freepage: yes +direct_IO: +get_xip_mem: maybe +migratepage: yes (both) +launder_page: yes +is_partially_uptodate: yes +error_remove_page: yes ->write_begin(), ->write_end(), ->sync_page() and ->readpage() may be called from the request handler (/dev/loop). @@ -276,9 +302,8 @@ under spinlock (it cannot block) and is sometimes called with the page not locked. ->bmap() is currently used by legacy ioctl() (FIBMAP) provided by some -filesystems and by the swapper. The latter will eventually go away. All -instances do not actually need the BKL. Please, keep it that way and don't -breed new callers. +filesystems and by the swapper. The latter will eventually go away. Please, +keep it that way and don't breed new callers. ->invalidatepage() is called when the filesystem must attempt to drop some or all of the buffers from the page when it is being truncated. It @@ -299,47 +324,37 @@ cleaned, or an error value if not. Note that in order to prevent the page getting mapped back in and redirtied, it needs to be kept locked across the entire operation. - Note: currently almost all instances of address_space methods are -using BKL for internal serialization and that's one of the worst sources -of contention. Normally they are calling library functions (in fs/buffer.c) -and pass foo_get_block() as a callback (on local block-based filesystems, -indeed). BKL is not needed for library stuff and is usually taken by -foo_get_block(). It's an overkill, since block bitmaps can be protected by -internal fs locking and real critical areas are much smaller than the areas -filesystems protect now. - ----------------------- file_lock_operations ------------------------------ prototypes: - void (*fl_insert)(struct file_lock *); /* lock insertion callback */ - void (*fl_remove)(struct file_lock *); /* lock removal callback */ void (*fl_copy_lock)(struct file_lock *, struct file_lock *); void (*fl_release_private)(struct file_lock *); locking rules: - BKL may block -fl_insert: yes no -fl_remove: yes no -fl_copy_lock: yes no -fl_release_private: yes yes + file_lock_lock may block +fl_copy_lock: yes no +fl_release_private: maybe no ----------------------- lock_manager_operations --------------------------- prototypes: int (*fl_compare_owner)(struct file_lock *, struct file_lock *); void (*fl_notify)(struct file_lock *); /* unblock callback */ + int (*fl_grant)(struct file_lock *, struct file_lock *, int); void (*fl_release_private)(struct file_lock *); void (*fl_break)(struct file_lock *); /* break_lease callback */ + int (*fl_mylease)(struct file_lock *, struct file_lock *); + int (*fl_change)(struct file_lock **, int); locking rules: - BKL may block -fl_compare_owner: yes no -fl_notify: yes no -fl_release_private: yes yes -fl_break: yes no - - Currently only NFSD and NLM provide instances of this class. None of the -them block. If you have out-of-tree instances - please, show up. Locking -in that area will change. + file_lock_lock may block +fl_compare_owner: yes no +fl_notify: yes no +fl_grant: no no +fl_release_private: maybe no +fl_break: yes no +fl_mylease: yes no +fl_change yes no + --------------------------- buffer_head ----------------------------------- prototypes: void (*b_end_io)(struct buffer_head *bh, int uptodate); @@ -364,17 +379,17 @@ prototypes: void (*swap_slot_free_notify) (struct block_device *, unsigned long); locking rules: - BKL bd_mutex -open: no yes -release: no yes -ioctl: no no -compat_ioctl: no no -direct_access: no no -media_changed: no no -unlock_native_capacity: no no -revalidate_disk: no no -getgeo: no no -swap_slot_free_notify: no no (see below) + bd_mutex +open: yes +release: yes +ioctl: no +compat_ioctl: no +direct_access: no +media_changed: no +unlock_native_capacity: no +revalidate_disk: no +getgeo: no +swap_slot_free_notify: no (see below) media_changed, unlock_native_capacity and revalidate_disk are called only from check_disk_change(). @@ -413,34 +428,21 @@ prototypes: unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long); int (*check_flags)(int); + int (*flock) (struct file *, int, struct file_lock *); + ssize_t (*splice_write)(struct pipe_inode_info *, struct file *, loff_t *, + size_t, unsigned int); + ssize_t (*splice_read)(struct file *, loff_t *, struct pipe_inode_info *, + size_t, unsigned int); + int (*setlease)(struct file *, long, struct file_lock **); }; locking rules: - All may block. - BKL -llseek: no (see below) -read: no -aio_read: no -write: no -aio_write: no -readdir: no -poll: no -unlocked_ioctl: no -compat_ioctl: no -mmap: no -open: no -flush: no -release: no -fsync: no (see below) -aio_fsync: no -fasync: no -lock: yes -readv: no -writev: no -sendfile: no -sendpage: no -get_unmapped_area: no -check_flags: no + All may block except for ->setlease. + No VFS locks held on entry except for ->fsync and ->setlease. + +->fsync() has i_mutex on inode. + +->setlease has the file_list_lock held and must not sleep. ->llseek() locking has moved from llseek to the individual llseek implementations. If your fs is not using generic_file_llseek, you @@ -450,17 +452,10 @@ mutex or just to use i_size_read() instead. Note: this does not protect the file->f_pos against concurrent modifications since this is something the userspace has to take care about. -Note: ext2_release() was *the* source of contention on fs-intensive -loads and dropping BKL on ->release() helps to get rid of that (we still -grab BKL for cases when we close a file that had been opened r/w, but that -can and should be done using the internal locking with smaller critical areas). -Current worst offender is ext2_get_block()... - -->fasync() is called without BKL protection, and is responsible for -maintaining the FASYNC bit in filp->f_flags. Most instances call -fasync_helper(), which does that maintenance, so it's not normally -something one needs to worry about. Return values > 0 will be mapped to -zero in the VFS layer. +->fasync() is responsible for maintaining the FASYNC bit in filp->f_flags. +Most instances call fasync_helper(), which does that maintenance, so it's +not normally something one needs to worry about. Return values > 0 will be +mapped to zero in the VFS layer. ->readdir() and ->ioctl() on directories must be changed. Ideally we would move ->readdir() to inode_operations and use a separate method for directory @@ -471,8 +466,6 @@ components. And there are other reasons why the current interface is a mess... ->read on directories probably must go away - we should just enforce -EISDIR in sys_read() and friends. -->fsync() has i_mutex on inode. - --------------------------- dquot_operations ------------------------------- prototypes: int (*write_dquot) (struct dquot *); @@ -507,12 +500,12 @@ prototypes: int (*access)(struct vm_area_struct *, unsigned long, void*, int, int); locking rules: - BKL mmap_sem PageLocked(page) -open: no yes -close: no yes -fault: no yes can return with page locked -page_mkwrite: no yes can return with page locked -access: no yes + mmap_sem PageLocked(page) +open: yes +close: yes +fault: yes can return with page locked +page_mkwrite: yes can return with page locked +access: yes ->fault() is called when a previously not present pte is about to be faulted in. The filesystem must find and return the page associated @@ -539,6 +532,3 @@ VM_IO | VM_PFNMAP VMAs. (if you break something or notice that it is broken and do not fix it yourself - at least put it here) - -ipc/shm.c::shm_delete() - may need BKL. -->read() and ->write() in many drivers are (probably) missing BKL. -- cgit v1.2.3 From 551423748a4eba55f2eb0fc250d757986471f187 Mon Sep 17 00:00:00 2001 From: Ben Hutchings Date: Sun, 2 Jan 2011 23:02:42 +0000 Subject: watchdog: Improve initialisation error message and documentation The error message 'NMI watchdog failed to create perf event...' does not make it clear that this is a fatal error for the watchdog. It also currently prints the error value as a pointer, rather than extracting the error code with PTR_ERR(). Fix that. Add a note to the description of the 'nowatchdog' kernel parameter to associate it with this message. Reported-by: Cesare Leonardi Signed-off-by: Ben Hutchings Cc: 599368@bugs.debian.org Cc: 608138@bugs.debian.org Cc: Don Zickus Cc: Frederic Weisbecker Cc: # .37.x and later LKML-Reference: <1294009362.3167.126.camel@localhost> Signed-off-by: Ingo Molnar --- Documentation/kernel-parameters.txt | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 8b61c936099..01ece1b9213 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1759,7 +1759,7 @@ and is between 256 and 4096 characters. It is defined in the file nousb [USB] Disable the USB subsystem - nowatchdog [KNL] Disable the lockup detector. + nowatchdog [KNL] Disable the lockup detector (NMI watchdog). nowb [ARM] -- cgit v1.2.3 From 8a87694ed159d7abd2c9ed657416696c05db2252 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 4 Jan 2011 07:14:24 +0100 Subject: remove trim_fs method from Documentation/filesystems/Locking The ->trim_fs has been removed meanwhile, so remove it from the documentation as well. Signed-off-by: Christoph Hellwig Reported-by: Ryusuke Konishi Signed-off-by: Linus Torvalds --- Documentation/filesystems/Locking | 2 -- 1 file changed, 2 deletions(-) (limited to 'Documentation') diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking index 7686e768449..33fa3e5d38f 100644 --- a/Documentation/filesystems/Locking +++ b/Documentation/filesystems/Locking @@ -115,7 +115,6 @@ prototypes: ssize_t (*quota_read)(struct super_block *, int, char *, size_t, loff_t); ssize_t (*quota_write)(struct super_block *, int, const char *, size_t, loff_t); int (*bdev_try_to_free_page)(struct super_block*, struct page*, gfp_t); - int (*trim_fs) (struct super_block *, struct fstrim_range *); locking rules: All may block [not true, see below] @@ -138,7 +137,6 @@ show_options: no (namespace_sem) quota_read: no (see below) quota_write: no (see below) bdev_try_to_free_page: no (see below) -trim_fs: no ->statfs() has s_umount (shared) when called by ustat(2) (native or compat), but that's an accident of bad API; s_umount is used to pin -- cgit v1.2.3