unpin_extent_cache() and add_extent_mapping() shares the same code
that merges extent maps.
Signed-off-by: Li Zefan <[email protected]>
Signed-off-by: Chris Mason <[email protected]>
lookup_extent_map() and search_extent_map() can share most of code.
Signed-off-by: Li Zefan <[email protected]>
Signed-off-by: Chris Mason <[email protected]>
rb_node returned by __tree_search() can be a valid pointer or NULL,
but won't be some errno.
Signed-off-by: Li Zefan <[email protected]>
Signed-off-by: Chris Mason <[email protected]>
When we search a dir item with a specific hash code, we can
just return NULL without further checking if btrfs_search_slot()
returns 1.
Signed-off-by: Li Zefan <[email protected]>
Signed-off-by: Chris Mason <[email protected]>
Since commit f2a97a9dbd
("btrfs: remove all unused functions"), there's no extern functions
at all in ref-cache.c, so just remove the remaining dead code.
Signed-off-by: Li Zefan <[email protected]>
Signed-off-by: Chris Mason <[email protected]>
If mounting with nodatasum option, we won't csum file data for
general write or direct-io write, and this rule should also be
applied when writing compressed files.
Signed-off-by: Li Zefan <[email protected]>
Signed-off-by: Chris Mason <[email protected]>
Memory areas [ptr, ptr+total_len] and [name, name+total_len]
may overlap, so it's wrong to use memcpy().
Signed-off-by: Li Zefan <[email protected]>
Signed-off-by: Chris Mason <[email protected]>
We passed the wrong value to btrfs_force_ra(). Fix this by changing
the argument of btrfs_force_ra() from last_index to nr_page.
Signed-off-by: Li Zefan <[email protected]>
Signed-off-by: Chris Mason <[email protected]>
The WARN_ON() in start_transaction() was triggered while balancing.
The cause is btrfs_relocate_chunk() started a transaction and
then called iput() on the inode that stores free space cache,
and iput() called btrfs_start_transaction() again.
Reported-by: Tsutomu Itoh <[email protected]>
Signed-off-by: Li Zefan <[email protected]>
Reviewed-by: Josef Bacik <[email protected]>
Signed-off-by: Chris Mason <[email protected]>
The size of struct btrfs_ioctl_fs_info_args is as big as 1KB, so
don't declare the variable on stack.
Signed-off-by: Li Zefan <[email protected]>
Reviewed-by: Josef Bacik <[email protected]>
Signed-off-by: Chris Mason <[email protected]>
For a filesystem that has lots of files in it, the first time we mount
it with free ino caching support, it can take quite a long time to
setup the caching before we can create new files.
Here we fill the cache with [highest_ino, BTRFS_LAST_FREE_OBJECTID]
before we start the caching thread to search through the extent tree.
Signed-off-by: Li Zefan <[email protected]>
Signed-off-by: Chris Mason <[email protected]>
Steps to reproduce the bug:
- Call FS_IOC_SETLFAGS ioctl with flags=FS_COMPR_FL
- Call FS_IOC_SETFLAGS ioctl with flags=0
- Call FS_IOC_GETFLAGS ioctl, and you'll see FS_COMPR_FL is still set!
Signed-off-by: Li Zefan <[email protected]>
Signed-off-by: Chris Mason <[email protected]>
FS_COW_FL and FS_NOCOW_FL were newly introduced to control per file
COW in btrfs, but FS_NOCOW_FL is sufficient.
The fact is we don't have corresponding BTRFS_INODE_COW flag.
COW is default, and FS_NOCOW_FL can be used to switch off COW for
a single file.
If we mount btrfs with nodatacow, a newly created file will be set with
the FS_NOCOW_FL flag. So to turn on COW for it, we can just clear the
FS_NOCOW_FL flag.
Signed-off-by: Li Zefan <[email protected]>
Signed-off-by: Chris Mason <[email protected]>
Since commit dc89e98244, we've changed
to use a specific slab for alocation of free_space items.
Signed-off-by: Li Zefan <[email protected]>
Signed-off-by: Chris Mason <[email protected]>
This is similar to block group caching.
We dedicate a special inode in fs tree to save free ino cache.
At the very first time we create/delete a file after mount, the free ino
cache will be loaded from disk into memory. When the fs tree is commited,
the cache will be written back to disk.
To keep compatibility, we check the root generation against the generation
of the special inode when loading the cache, so the loading will fail
if the btrfs filesystem was mounted in an older kernel before.
Signed-off-by: Li Zefan <[email protected]>
There's a potential problem in 32bit system when we exhaust 32bit inode
numbers and start to allocate big inode numbers, because btrfs uses
inode->i_ino in many places.
So here we always use BTRFS_I(inode)->location.objectid, which is an
u64 variable.
There are 2 exceptions that BTRFS_I(inode)->location.objectid !=
inode->i_ino: the btree inode (0 vs 1) and empty subvol dirs (256 vs 2),
and inode->i_ino will be used in those cases.
Another reason to make this change is I'm going to use a special inode
to save free ino cache, and the inode number must be > (u64)-256.
Signed-off-by: Li Zefan <[email protected]>
Extract out block group specific code from lookup_free_space_inode(),
create_free_space_inode(), load_free_space_cache() and
btrfs_write_out_cache(), so the code can be used to read/write
free ino cache.
Signed-off-by: Li Zefan <[email protected]>
Currently btrfs stores the highest objectid of the fs tree, and it always
returns (highest+1) inode number when we create a file, so inode numbers
won't be reclaimed when we delete files, so we'll run out of inode numbers
as we keep create/delete files in 32bits machines.
This fixes it, and it works similarly to how we cache free space in block
cgroups.
We start a kernel thread to read the file tree. By scanning inode items,
we know which chunks of inode numbers are free, and we cache them in
an rb-tree.
Because we are searching the commit root, we have to carefully handle the
cross-transaction case.
The rb-tree is a hybrid extent+bitmap tree, so if we have too many small
chunks of inode numbers, we'll use bitmaps. Initially we allow 16K ram
of extents, and a bitmap will be used if we exceed this threshold. The
extents threshold is adjusted in runtime.
Signed-off-by: Li Zefan <[email protected]>
So we can re-use the code to cache free inode numbers.
The change is quite straightforward. Two new structures are introduced.
- struct btrfs_free_space_ctl
We move those variables that are used for caching free space from
struct btrfs_block_group_cache to this new struct.
- struct btrfs_free_space_op
We do block group specific work (e.g. calculation of extents threshold)
through functions registered in this struct.
And then we can remove references to struct btrfs_block_group_cache.
Signed-off-by: Li Zefan <[email protected]>
btrfs_next_leaf() can return -errno, and we should propagate
it to userspace.
This also simplifies how we walk the btree path.
Signed-off-by: Li Zefan <[email protected]>
btrfs_next_leaf() can return -errno, and we should propagate
it to userspace.
This also simplifies how we walk the btree path.
Signed-off-by: Li Zefan <[email protected]>
There's no config named SLAB_DEBUG, and it should be a typo
of SLUB_DEBUG.
Acked-by: Christoph Lameter <[email protected]>
Signed-off-by: Li Zefan <[email protected]>
Signed-off-by: Pekka Enberg <[email protected]>
root_item->flags and root_item->byte_limit are not initialized when
a subvolume is created. This bug is not revealed until we added
readonly snapshot support - now you mount a btrfs filesystem and you
may find the subvolumes in it are readonly.
To work around this problem, we steal a bit from root_item->inode_item->flags,
and use it to indicate if those fields have been properly initialized.
When we read a tree root from disk, we check if the bit is set, and if
not we'll set the flag and initialize the two fields of the root item.
Reported-by: Andreas Philipp <[email protected]>
Signed-off-by: Li Zefan <[email protected]>
Tested-by: Andreas Philipp <[email protected]>
cc: [email protected]
Signed-off-by: Chris Mason <[email protected]>
When we defrag a file, whose size can be fit into an inline extent,
with compression enabled, the compress type is set to be
fs_info->compress_type, which is 0 if the btrfs filesystem is mounted
without compress option. This leads to oops.
Reported-by: Daniel Blueman <[email protected]>
Signed-off-by: Li Zefan <[email protected]>
Signed-off-by: Chris Mason <[email protected]>
Chaning cpuset->mems/cpuset->cpus should be protected under
callback_mutex.
cpuset_clone() doesn't follow this rule. It's ok because it's
called when creating and initializing a cgroup, but we'd better
hold the lock to avoid subtil break in the future.
Signed-off-by: Li Zefan <[email protected]>
Acked-by: Paul Menage <[email protected]>
Acked-by: David Rientjes <[email protected]>
Cc: Miao Xie <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Those functions that use NODEMASK_ALLOC() can't propagate errno
to users, but will fail silently.
Fix it by using a static nodemask_t variable for each function, and
those variables are protected by cgroup_mutex;
[[email protected]: fix comment spelling, strengthen cgroup_lock comment]
Signed-off-by: Li Zefan <[email protected]>
Cc: Paul Menage <[email protected]>
Acked-by: David Rientjes <[email protected]>
Cc: Miao Xie <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
oldcs->mems_allowed is not modified during cpuset_attach(), so we don't
have to copy it to a buffer allocated by NODEMASK_ALLOC(). Just pass it
to cpuset_migrate_mm().
Signed-off-by: Li Zefan <[email protected]>
Cc: Paul Menage <[email protected]>
Acked-by: David Rientjes <[email protected]>
Cc: Miao Xie <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
It's not necessary to copy cpuset->mems_allowed to a buffer allocated by
NODEMASK_ALLOC(). Just pass it to nodelist_scnprintf().
As spotted by Paul, a side effect is we fix a bug that the function can
return -ENOMEM but the caller doesn't expect negative return value.
Therefore change the return value of cpuset_sprintf_cpulist() and
cpuset_sprintf_memlist() from int to size_t.
Signed-off-by: Li Zefan <[email protected]>
Acked-by: Paul Menage <[email protected]>
Acked-by: David Rientjes <[email protected]>
Cc: Miao Xie <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
When decompressing a chunk of data, we'll copy the data out to
a working buffer if the data is stored in more than one page,
otherwise we'll use the mapped page directly to avoid memory
copy.
In the latter case, we'll end up accessing the kernel address
after we've unmapped the page in a corner case.
Reported-by: Juan Francisco Cantero Hurtado <[email protected]>
Signed-off-by: Li Zefan <[email protected]>
Signed-off-by: Chris Mason <[email protected]>
- Check user-specified flags correctly
- Check the inode owership
- Search root item in root tree but not fs tree
Reported-by: Dan Rosenberg <[email protected]>
Signed-off-by: Li Zefan <[email protected]>
Signed-off-by: Chris Mason <[email protected]>
Suppose:
- the source extent is: [0, 100]
- the src offset is 10
- the clone length is 90
- the dest offset is 0
This statement:
new_key.offset = key.offset + destoff - off
will produce such an extent for the dest file:
[ino, BTRFS_EXTENT_DATA_KEY, -10]
, which is obviously wrong.
Signed-off-by: Li Zefan <[email protected]>
After returing extents from a cluster to the block group, some
extents in the block group may be mergeable.
Reviewed-by: Josef Bacik <[email protected]>
Signed-off-by: Li Zefan <[email protected]>
When adding a new extent, we'll firstly see if we can merge
this extent to the left or/and right extent. Extract this as
a helper try_merge_free_space().
As a side effect, we fix a small bug that if the new extent
has non-bitmap left entry but is unmergeble, we'll directly
link the extent without trying to drop it into bitmap.
This also prepares for the next patch.
Reviewed-by: Josef Bacik <[email protected]>
Signed-off-by: Li Zefan <[email protected]>
When allocating extent entry from a cluster, we should update
the free_space and free_extents fields of the block group.
Reviewed-by: Josef Bacik <[email protected]>
Signed-off-by: Li Zefan <[email protected]>
Remove some duplicated code.
This prepares for the next patch.
Reviewed-by: Josef Bacik <[email protected]>
Signed-off-by: Li Zefan <[email protected]>
If a block group is smaller than 1GB, the extent entry threadhold
calculation will always set the threshold to 0.
So as free space gets fragmented, btrfs will switch to use bitmap
to manage free space, but then will never switch back to extents
due to this bug.
Reviewed-by: Josef Bacik <[email protected]>
Signed-off-by: Li Zefan <[email protected]>
While running my ftrace stress test, this showed up:
BUG: sleeping function called from invalid context at mm/mmap.c:233
...
note: cat[3293] exited with preempt_count 1
The bug was introduced by commit 91e86e560d
("tracing: Fix recursive user stack trace")
Cc: <[email protected]>
Signed-off-by: Li Zefan <[email protected]>
LKML-Reference: <[email protected]>
Signed-off-by: Steven Rostedt <[email protected]>
This allows us to set a snapshot or a subvolume readonly or writable
on the fly.
Usage:
Set BTRFS_SUBVOL_RDONLY of btrfs_ioctl_vol_arg_v2->flags, and then
call ioctl(BTRFS_IOCTL_SUBVOL_SETFLAGS);
Changelog for v3:
- Change to pass __u64 as ioctl parameter.
Changelog for v2:
- Add _GETFLAGS ioctl.
- Check if the passed fd is the root of a subvolume.
- Change the name from _SNAP_SETFLAGS to _SUBVOL_SETFLAGS.
Signed-off-by: Li Zefan <[email protected]>
Usage:
Set BTRFS_SUBVOL_RDONLY of btrfs_ioctl_vol_arg_v2->flags, and call
ioctl(BTRFS_I0CTL_SNAP_CREATE_V2).
Implementation:
- Set readonly bit of btrfs_root_item->flags.
- Add readonly checks in btrfs_permission (inode_permission),
btrfs_setattr, btrfs_set/remove_xattr and some ioctls.
Changelog for v3:
- Eliminate btrfs_root->readonly, but check btrfs_root->root_item.flags.
- Rename BTRFS_ROOT_SNAP_RDONLY to BTRFS_ROOT_SUBVOL_RDONLY.
Signed-off-by: Li Zefan <[email protected]>
Update defrag ioctl, so one can choose lzo or zlib when turning
on compression in defrag operation.
Changelog:
v1 -> v2
- Add incompability flag.
- Fix to check invalid compress type.
Signed-off-by: Li Zefan <[email protected]>
Lzo is a much faster compression algorithm than gzib, so would allow
more users to enable transparent compression, and some users can
choose from compression ratio and speed for different applications
Usage:
# mount -t btrfs -o compress[=<zlib,lzo>] dev /mnt
or
# mount -t btrfs -o compress-force[=<zlib,lzo>] dev /mnt
"-o compress" without argument is still allowed for compatability.
Compatibility:
If we mount a filesystem with lzo compression, it will not be able be
mounted in old kernels. One reason is, otherwise btrfs will directly
dump compressed data, which sits in inline extent, to user.
Performance:
The test copied a linux source tarball (~400M) from an ext4 partition
to the btrfs partition, and then extracted it.
(time in second)
lzo zlib nocompress
copy: 10.6 21.7 14.9
extract: 70.1 94.4 66.6
(data size in MB)
lzo zlib nocompress
copy: 185.87 108.69 394.49
extract: 193.80 132.36 381.21
Changelog:
v1 -> v2:
- Select LZO_COMPRESS and LZO_DECOMPRESS in btrfs Kconfig.
- Add incompability flag.
- Fix error handling in compress code.
Signed-off-by: Li Zefan <[email protected]>
Make the code aware of compression type, instead of always assuming
zlib compression.
Also make the zlib workspace function as common code for all
compression types.
Signed-off-by: Li Zefan <[email protected]>
If we had reserved some bytes in struct btrfs_ioctl_vol_args, we
wouldn't have to create a new structure for async snapshot creation.
Here we convert async snapshot ioctl to use a more generic ABI, as
we'll add more ioctls for snapshots/subvolumes in the future, readonly
snapshots for example.
Signed-off-by: Li Zefan <[email protected]>
Signed-off-by: Chris Mason <[email protected]>
We should drop dentry before deactivating the superblock, otherwise
we can hit this bug:
BUG: Dentry f349a690{i=100,n=/} still in use (1) [unmount of btrfs loop1]
...
Steps to reproduce the bug:
# mount /dev/loop1 /mnt
# mkdir save
# btrfs subvolume snapshot /mnt save/snap1
# umount /mnt
# mount -o subvol=save/snap1 /dev/loop1 /mnt
(crash)
Reported-by: Michael Niederle <[email protected]>
Signed-off-by: Li Zefan <[email protected]>
Signed-off-by: Chris Mason <[email protected]>
Set src_offset = 0, src_length = 20K, dest_offset = 20K. And the
original filesize of the dest file 'file2' is 30K:
# ls -l /mnt/file2
-rw-r--r-- 1 root root 30720 Nov 18 16:42 /mnt/file2
Now clone file1 to file2, the dest file should be 40K, but it
still shows 30K:
# ls -l /mnt/file2
-rw-r--r-- 1 root root 30720 Nov 18 16:42 /mnt/file2
Signed-off-by: Li Zefan <[email protected]>
Signed-off-by: Chris Mason <[email protected]>
We've done the check for src_offset and src_length, and We should
also check dest_offset, otherwise we'll corrupt the destination
file:
(After cloning file1 to file2 with unaligned dest_offset)
# cat /mnt/file2
cat: /mnt/file2: Input/output error
Signed-off-by: Li Zefan <[email protected]>
Signed-off-by: Chris Mason <[email protected]>
Dave reported an rcu lockdep warning on 2.6.35.4 kernel
task->cgroups and task->cgroups->subsys[i] are protected by RCU.
So we avoid accessing invalid pointers here. This might happen,
for example, when you are deref-ing those pointers while someone
move @task from one cgroup to another.
Reported-by: Dave Jones <[email protected]>
Signed-off-by: Li Zefan <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
While we are reading trace_stat/functionX and someone just
disabled function_profile at that time, we can trigger this:
divide error: 0000 [#1] PREEMPT SMP
...
EIP is at function_stat_show+0x90/0x230
...
This fix just takes the ftrace_profile_lock and checks if
rec->counter is 0. If it's 0, we know the profile buffer
has been reset.
Signed-off-by: Li Zefan <[email protected]>
Cc: [email protected]
LKML-Reference: <[email protected]>
Signed-off-by: Steven Rostedt <[email protected]>
Remove the nasty hack that marks a pointer's LSB to distinguish common
fields from event fields. Replace it with a more sane approach.
Signed-off-by: Li Zefan <[email protected]>
LKML-Reference: <[email protected]>
Signed-off-by: Steven Rostedt <[email protected]>
We found that even enabling a single trace event that will rarely be
triggered can add big overhead to context switch.
(lmbench context switch test)
-------------------------------------------------
2p/0K 2p/16K 2p/64K 8p/16K 8p/64K 16p/16K 16p/64K
ctxsw ctxsw ctxsw ctxsw ctxsw ctxsw ctxsw
------ ------ ------ ------ ------ ------- -------
2.19 2.3 2.21 2.56 2.13 2.54 2.07
2.39 2.51 2.35 2.75 2.27 2.81 2.24
The overhead is 6% ~ 11%.
It's because when a trace event is enabled 3 tracepoints (sched_switch,
sched_wakeup, sched_wakeup_new) will be activated to map pid to cmdname.
We'd like to avoid this overhead, so add a trace option '(no)record-cmd'
to allow to disable cmdline recording.
Signed-off-by: Li Zefan <[email protected]>
LKML-Reference: <[email protected]>
Signed-off-by: Steven Rostedt <[email protected]>
Let trace_module_add_events() and event_trace_init() call
__trace_add_event_call().
Signed-off-by: Li Zefan <[email protected]>
LKML-Reference: <[email protected]>
Signed-off-by: Steven Rostedt <[email protected]>
Every event (or event class) has it's define_fields callback,
so the test is redundant.
Signed-off-by: Li Zefan <[email protected]>
LKML-Reference: <[email protected]>
Signed-off-by: Steven Rostedt <[email protected]>
Convert sched_wait_task to DEFINE_EVENT, and save ~1K:
text data bss dec hex filename
104595 9424 4992 119011 1d0e3 kernel/sched.o.orig
103619 9344 4992 117955 1ccc3 kernel/sched.o
No change in functionality.
Signed-off-by: Li Zefan <[email protected]>
LKML-Reference: <[email protected]>
Signed-off-by: Steven Rostedt <[email protected]>
Use DECLARE_EVENT_CLASS, and save ~2.3K:
text data bss dec hex filename
7018823 2031888 7251132 16301843 f8bf13 vmlinux.o.orig
7016727 2031696 7251132 16299555 f8b623 vmlinux.o
5 events are converted:
timer_class: timer_init, timer_expire_exit, timer_cancel
hrtimer_class: hrtimer_init, hrtimer_cancel
No change in functionality.
Signed-off-by: Li Zefan <[email protected]>
LKML-Reference: <[email protected]>
Signed-off-by: Steven Rostedt <[email protected]>
Every event has the same common fields, so it's a big waste of
memory to have a copy of those fields for every event.
Signed-off-by: Li Zefan <[email protected]>
LKML-Reference: <[email protected]>
Signed-off-by: Steven Rostedt <[email protected]>
All syscall exit events have the same fields.
The kernel size drops 2.5K:
text data bss dec hex filename
7018612 2034376 7251132 16304120 f8c7f8 vmlinux.o.orig
7018612 2031888 7251132 16301632 f8be40 vmlinux.o
Signed-off-by: Li Zefan <[email protected]>
LKML-Reference: <[email protected]>
Signed-off-by: Steven Rostedt <[email protected]>
We have been resisting new ftrace plugins and removing existing
ones, and kmemtrace has been superseded by kmem trace events
and perf-kmem, so we remove it.
Signed-off-by: Li Zefan <[email protected]>
Acked-by: Pekka Enberg <[email protected]>
Acked-by: Eduard - Gabriel Munteanu <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Steven Rostedt <[email protected]>
[ remove kmemtrace from the makefile, handle slob too ]
Signed-off-by: Frederic Weisbecker <[email protected]>
Truncate list items to fit in a single line, otherwise those items
which have long prompts will cover some other items.
This follows the behavior of menubox.
Signed-off-by: Li Zefan <[email protected]>
Signed-off-by: Michal Marek <[email protected]>
Run:
make ARCH=arm menuconfig
And then select "System Type" -> "ARM system type". The kconfig
"choice" menu at this point looks empty.
It's because config ARCH_S3C2410 has a long prompt:
config ARCH_S3C2410
bool "Samsung S3C2410, S3C2412, S3C2413, S3C2416, S3C2440, S3C2442, S3C2443, S3C2450"
...
menuconfig centers the checklist according to this prompt without
considering the width of the list, and then things get wrong.
Reported-by: Nobin Mathew <[email protected]>
Signed-off-by: Li Zefan <[email protected]>
Signed-off-by: Michal Marek <[email protected]>
This feature has been supported in menuconfig and gconfig, so
here add it to xconfig.
Signed-off-by: Li Zefan <[email protected]>
Signed-off-by: Michal Marek <[email protected]>
@ok is a pointer to a bool var, so we should check the value of
*ok. But actually we don't need to check it, so just remove the
if statement.
Signed-off-by: Li Zefan <[email protected]>
Signed-off-by: Michal Marek <[email protected]>
In gconfig if you enable "Show all options", you'll see some "(null)"
config options, and clicking those options triggers a warning:
(gconf:9368): Gtk-CRITICAL **: gtk_text_buffer_insert_with_tags: assertion `text != NULL' failed
Signed-off-by: Li Zefan <[email protected]>
Acked-by: Randy Dunlap <[email protected]>
Signed-off-by: Michal Marek <[email protected]>
Those configs are not new:
$ cat .config
...
CONFIG_NAMESPACES=y
...
CONFIG_BLOCK=y
...
But are tagged as NEW:
$ yes "" | make config > myconf
$ cat myconf | grep '(NEW)'
Namespaces support (NAMESPACES) [Y/?] (NEW) y
...
Enable the block layer (BLOCK) [Y/?] (NEW) y
...
You can also notice this bug when using gconfig/xconfig.
It's because the SYMBOL_DEF_USER bit of an invisible symbol is cleared
when the config file is read:
int conf_read(const char *name)
{
...
for_all_symbols(i, sym) {
if (sym_has_value(sym) && !sym_is_choice_value(sym)) {
/* Reset values of generates values, so they'll appear
* as new, if they should become visible, but that
* doesn't quite work if the Kconfig and the saved
* configuration disagree.
*/
if (sym->visible == no && !conf_unsaved)
sym->flags &= ~SYMBOL_DEF_USER;
...
}
But a menu item which represents an invisible symbol is still
visible, if it's sub-menu is visible, so its SYMBOL_DEF_USER
bit should be set to indicate it's not NEW.
Signed-off-by: Li Zefan <[email protected]>
Signed-off-by: Michal Marek <[email protected]>
Without this patch, one has to refer to the Kconfig file to find
out the range of an integer/hex symbol.
│ Symbol: NR_CPUS [=4]
│ Type : integer
│ Range : [2 8]
│ Prompt: Maximum number of CPUs
│ Defined at arch/x86/Kconfig:761
│ Depends on: SMP [=y] && !MAXSMP [=n]
│ Location:
│ -> Processor type and features
Signed-off-by: Li Zefan <[email protected]>
Signed-off-by: Michal Marek <[email protected]>
Randy suggested to print out the symbol type in gconfig.
Note this change does more than Randy's suggestion, that it also
affects menuconfig and "make config".
│ Symbol: BLOCK [=y]
│ Type : boolean
│ Prompt: Enable the block layer
│ Defined at block/Kconfig:4
│ Depends on: EMBEDDED [=n]
Signed-off-by: Li Zefan <[email protected]>
Acked-by: Randy Dunlap <[email protected]>
Signed-off-by: Michal Marek <[email protected]>
Use DECLARE_EVENT_CLASS, and save ~15K:
text data bss dec hex filename
171949 43028 48 215025 347f1 fs/xfs/linux-2.6/xfs_trace.o.orig
156521 43028 36 199585 30ba1 fs/xfs/linux-2.6/xfs_trace.o
No change in functionality.
Signed-off-by: Li Zefan <[email protected]>
Acked-by: Steven Rostedt <[email protected]>
Signed-off-by: Alex Elder <[email protected]>
Convert i915_gem_object_clflush to DEFINE_EVENT, and save ~0.5K:
text data bss dec hex filename
13204 2732 12 15948 3e4c i915_trace_points.o.orig
12668 2732 12 15412 3c34 i915_trace_points.o
No change in functionality.
Signed-off-by: Li Zefan <[email protected]>
Acked-by: Steven Rostedt <[email protected]>
Signed-off-by: Eric Anholt <[email protected]>
Use DECLARE_EVENT_CLASS, and save ~2.7K:
text data bss dec hex filename
274441 7200 260 281901 44d2d fs/ext4/ext4.o.orig
271881 7040 256 279177 44289 fs/ext4/ext4.o
4 events are converted:
ext4__mb_new_pa: ext4_mb_new_inode_pa, ext4_mb_new_group_pa
ext4__mballoc: ext4_mballoc_discard, ext4_mballoc_free
No change in functionality.
Signed-off-by: Li Zefan <[email protected]>
Signed-off-by: "Theodore Ts'o" <[email protected]>
ftrace_trace_stack() and frace_trace_userstacke() take a
struct ring_buffer argument, not struct trace_array. Commit
e77405ad("tracing: pass around ring buffer instead of tracer")
made this change.
Signed-off-by: Li Zefan <[email protected]>
LKML-Reference: <[email protected]>
Signed-off-by: Steven Rostedt <[email protected]>
with CONFIG_PROVE_RCU=y, a warning can be triggered:
# mount -t cgroup -o blkio xxx /mnt
# mkdir /mnt/subgroup
...
kernel/cgroup.c:4442 invoked rcu_dereference_check() without protection!
...
To fix this, we avoid caling css_depth() here, which is a bit simpler
than the original code.
Signed-off-by: Li Zefan <[email protected]>
Acked-by: Vivek Goyal <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>
Expand task_subsys_state()'s rcu_dereference_check() to include the full
locking rule as documented in Documentation/cgroups/cgroups.txt by adding
a check for task->alloc_lock being held.
This fixes an RCU false positive when resuming from suspend. The warning
comes from freezer cgroup in cgroup_freezing_or_frozen().
Signed-off-by: Li Zefan <[email protected]>
Acked-by: Matt Helsley <[email protected]>
Signed-off-by: Paul E. McKenney <[email protected]>
With CONFIG_PROVE_RCU=y, a warning can be triggered:
$ cat /proc/sched_debug
...
kernel/cgroup.c:1649 invoked rcu_dereference_check() without protection!
...
Both cgroup_path() and task_group() should be called with either
rcu_read_lock or cgroup_mutex held.
The rcu_dereference_check() does include cgroup_lock_is_held(), so we
know that this lock is not held. Therefore, in a CONFIG_PREEMPT kernel,
to say nothing of a CONFIG_PREEMPT_RT kernel, the original code could
have ended up copying a string out of the freelist.
This patch inserts RCU read-side primitives needed to prevent this
scenario.
Signed-off-by: Li Zefan <[email protected]>
Signed-off-by: Paul E. McKenney <[email protected]>
Li Zefan