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We don't support gss on the backchannel. We should state that fact up
front rather than just letting things continue and later making the
client try to figure out why the backchannel isn't working.
Trond suggested instead returning NFS4ERR_NOENT. I think it would be
tricky for the client to distinguish between the case "I don't support
gss on the backchannel" and "I can't find that in my cache, please
create another context and try that instead", and I'd prefer something
that currently doesn't have any other meaning for this operation, hence
the (somewhat arbitrary) NFS4ERR_ENCR_ALG_UNSUPP.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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Do a minimal SP4_MACH_CRED implementation suggested by Trond, ignoring
the client-provided spo_must_* arrays and just enforcing credential
checks for the minimum required operations.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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Store a pointer to the gss mechanism used in the rq_cred and cl_cred.
This will make it easier to enforce SP4_MACH_CRED, which needs to
compare the mechanism used on the exchange_id with that used on
protected operations.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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Change Low Latency Sockets code for select and poll so that
when LLS is disabled sched_clock() is never called.
Also, avoid sending POLL_LL to sockets if disabled.
Reported-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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I introduced a new temporary variable "info" instead of
"m->m_info[mds]". Also I reversed the if condition and pulled
everything in one indent level.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Alex Elder <elder@inktank.com>
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This patch makes the following improvements to the error handling
in the ceph_mdsmap_decode function:
- Add a NULL check for return value from kcalloc
- Make use of the variable err
Signed-off-by: Emil Goode <emilgoode@gmail.com>
Signed-off-by: Sage Weil <sage@inktank.com>
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Signed-off-by: Jim Schutt <jaschut@sandia.gov>
Reviewed-by: Alex Elder <elder@inktank.com>
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This has plagued us forever and I'm so over working around it. When we truncate
down to a non-page aligned offset we will call btrfs_truncate_page to zero out
the end of the page and write it back to disk, this will keep us from exposing
stale data if we truncate back up from that point. The problem with this is it
requires data space to do this, and people don't really expect to get ENOSPC
from truncate() for these sort of things. This also tends to bite the orphan
cleanup stuff too which keeps people from mounting. To get around this we can
just move this into btrfs_cont_expand() to make sure if we are truncating up
from a non-page size aligned i_size we will zero out the rest of this page so
that we don't expose stale data. This will give ENOSPC if you try to truncate()
up or if you try to write past the end of isize, which is much more reasonable.
This fixes xfstests generic/083 failing to mount because of the orphan cleanup
failing. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
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This patch does two things. First we no longer explicitly read in the blocks
we're trying to readahead. For things like balance_level we may never actually
use the blocks so this just adds uneeded latency, and balance_level and
split_node will both read in the blocks they care about explicitly so if the
blocks need to be waited on it will be done there. Secondly we no longer drop
the path if we do readahead, we just set the path blocking before we call
reada_for_balance() and then we're good to go. Hopefully this will cut down on
the number of re-searches. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
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This patch does two things, first it only does one call to
btrfs_buffer_uptodate() with the gen specified instead of once with 0 and then
again with gen specified. The other thing is to call btrfs_read_buffer() on the
buffer we've found instead of dropping it and then calling read_tree_block().
This will keep us from doing yet another radix tree lookup for a buffer we've
already found. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
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A user reported a deadlock where the async submit thread was blocked on the
lock_extent() lock, and then everybody behind him was locked on the page lock
for the page he was holding. Looking at the code I noticed we do not unlock the
extent range when we get ENOSPC and goto retry. This is bad because we
immediately try to lock that range again to do the cow, which will cause a
deadlock. Fix this by unlocking the range. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
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The comment is for btrfs_attach_transaction_barrier, not for
btrfs_attach_transaction. Fix the typo.
Signed-off-by: Wang Sheng-Hui <shhuiw@gmail.com>
Acked-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
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We unconditionally search for the EXTENT_ITEM_KEY for metadata during balance,
and then check the key that we found to see if it is actually a
METADATA_ITEM_KEY, but this doesn't work right because METADATA is a higher key
value, so if what we are looking for happens to be the first item in the leaf
the search will dump us out at the previous leaf, and we won't find our item.
So instead do what we do everywhere else, search for the skinny extent first and
if we don't find it go back and re-search for the extent item. This patch fixes
the panic I was hitting when balancing a large file system with skinny extents.
Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
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Looking into this backref problem I noticed we're using a macro to what turns
out to essentially be a NULL check to see if we need to search the commit root.
I'm killing this, let's just do what everybody else does and checks if trans ==
NULL. I've also made it so we pass in the path to __resolve_indirect_refs which
will have the search_commit_root flag set properly already and that way we can
avoid allocating another path when we have a perfectly good one to use. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
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A user reported scrub taking up an unreasonable amount of ram as it ran. This
is because we lookup the csums for the extent we're scrubbing but don't free it
up until after we're done with the scrub, which means we can take up a whole lot
of ram. This patch fixes this by dropping the csums once we're done with the
extent we've scrubbed. The user reported this to fix their problem. Thanks,
Reported-and-tested-by: Remco Hosman <remco@hosman.xs4all.nl>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
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Dave has this fs_mark script that can make btrfs abort with sufficient amount of
ram. This is because with more ram we can keep more dirty metadata in cache
which in a round about way makes for many more pending delayed refs. What
happens is we end up not throttling the transaction enough so when we go to
commit the transaction when we've completely filled the file system we'll
abort() because we use all of the space in the global reserve and we still have
delayed refs to run. To fix this we need to make the delayed ref flushing and
the transaction throttling dependant upon the number of delayed refs that we
have instead of how much reserved space is left in the global reserve. With
this patch we not only stop aborting transactions but we also get a smoother run
speed with fs_mark and it makes us about 10% faster. Thanks,
Reported-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
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I hit a hang when run_delayed_refs returned an error in the beginning of
btrfs_commit_transaction. If we decide we need to commit the transaction in
btrfs_end_transaction we'll set BLOCKED and start to commit, but if we get an
error this early on we'll just exit without committing. This is fine, except
that anybody else who tried to start a transaction will sit in
wait_current_trans() since we're set to BLOCKED and we never set it to something
else and woke people up. To fix this we want to check for trans->aborted
everywhere we wait for the transaction state to change, and make
btrfs_abort_transaction() wake up any waiters there may be. All the callers
will notice that the transaction has aborted and exit out properly. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
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I hit a deadlock because we aborted when flushing delayed refs but didn't wake
any of the other flushers up and so everybody was just sleeping forever. This
should fix the problem. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
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Fix the code comments for lzo compression workspace.
The buf item is used to store the decompressed data
and cbuf is used to store the compressed data.
Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
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Balance will create reloc_root for each fs root, and it's going to
record last_snapshot to filter shared blocks. The side effect of
setting last_snapshot is to break nocow attributes of files.
Since the extents are not shared by the relocation tree after the balance,
we can recover the old last_snapshot safely if no one snapshoted the
source tree. We fix the above problem by this way.
Reported-by: Kyle Gates <kylegates@hotmail.com>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
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Both hole punch and truncate use ext4_ext_rm_leaf() for removing
blocks. Currently we choose the last extent as the starting
point for removing blocks:
ex = EXT_LAST_EXTENT(eh);
This is OK for truncate but for hole punch we can optimize the extent
selection as the path is already initialized. We could use this
information to select proper starting extent. The code change in this
patch will not affect truncate as for truncate path[depth].p_ext will
always be NULL.
Signed-off-by: Ashish Sangwan <a.sangwan@samsung.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
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If jbd2_journal_restart() fails the handle will have been disconnected
from the current transaction. In this situation, the handle must not
be used for for any jbd2 function other than jbd2_journal_stop().
Enforce this with by treating a handle which has a NULL transaction
pointer as an aborted handle, and issue a kernel warning if
jbd2_journal_extent(), jbd2_journal_get_write_access(),
jbd2_journal_dirty_metadata(), etc. is called with an invalid handle.
This commit also fixes a bug where jbd2_journal_stop() would trip over
a kernel jbd2 assertion check when trying to free an invalid handle.
Also move the responsibility of setting current->journal_info to
start_this_handle(), simplifying the three users of this function.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reported-by: Younger Liu <younger.liu@huawei.com>
Cc: Jan Kara <jack@suse.cz>
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Translate the bitfields used in various flags argument to strings to
make the tracepoint output more human-readable.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
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The function mpage_released_unused_page() must only be called once;
otherwise the kernel will BUG() when the second call to
mpage_released_unused_page() tries to unlock the pages which had been
unlocked by the first call.
Also restructure the error handling so that we only give up on writing
the dirty pages in the case of ENOSPC where retrying the allocation
won't help. Otherwise, a transient failure, such as a kmalloc()
failure in calling ext4_map_blocks() might cause us to give up on
those pages, leading to a scary message in /var/log/messages plus data
loss.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
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Once we decrement transaction->t_updates, if this is the last handle
holding the transaction from closing, and once we release the
t_handle_lock spinlock, it's possible for the transaction to commit
and be released. In practice with normal kernels, this probably won't
happen, since the commit happens in a separate kernel thread and it's
unlikely this could all happen within the space of a few CPU cycles.
On the other hand, with a real-time kernel, this could potentially
happen, so save the tid found in transaction->t_tid before we release
t_handle_lock. It would require an insane configuration, such as one
where the jbd2 thread was set to a very high real-time priority,
perhaps because a high priority real-time thread is trying to read or
write to a file system. But some people who use real-time kernels
have been known to do insane things, including controlling
laser-wielding industrial robots. :-)
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org
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Currently if we pass range into ext4_zero_partial_blocks() which covers
entire block we would attempt to zero it even though we should only zero
unaligned part of the block.
Fix this by checking whether the range covers the whole block skip
zeroing if so.
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
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The function ext4_write_inline_data_end() can return an error. So we
need to assign it to a signed integer variable to check for an error
return (since copied is an unsigned int).
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Zheng Liu <wenqing.lz@taobao.com>
Cc: stable@vger.kernel.org
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Comparing unsigned variable with 0 always returns false.
err = 0 is duplicated and unnecessary.
[ tytso: Also cleaned up error handling in ext4_block_zero_page_range() ]
Signed-off-by: "Jon Ernst" <jonernst07@gmx.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
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Both ext3 and ext4 htree_dirblock_to_tree() is just filling the
in-core rbtree for use by call_filldir(). All updates of ->f_pos are
done by the latter; bumping it here (on error) is obviously wrong - we
might very well have it nowhere near the block we'd found an error in.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org
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Some of the functions which modify the jbd2 superblock were not
updating the checksum before calling jbd2_write_superblock(). Move
the call to jbd2_superblock_csum_set() to jbd2_write_superblock(), so
that the checksum is calculated consistently.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: stable@vger.kernel.org
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No need to pass file pointer when we can directly pass inode pointer.
Signed-off-by: Ashish Sangwan <a.sangwan@samsung.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
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In ext4 feature inline_data,it use the xattr's space to store the
inline data in inode.When we calculate the inline data as the xattr,we
add the pad.But in get_max_inline_xattr_value_size() function we count
the free space without pad.It cause some contents are moved to a block
even if it can be
stored in the inode.
Signed-off-by: liulei <lewis.liulei@huawei.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Tao Ma <boyu.mt@taobao.com>
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Reduce the object size ~10% could be useful for embedded systems.
Add #ifdef CONFIG_PRINTK #else #endif blocks to hold formats and
arguments, passing " " to functions when !CONFIG_PRINTK and still
verifying format and arguments with no_printk.
$ size fs/ext4/built-in.o*
text data bss dec hex filename
239375 610 888 240873 3ace9 fs/ext4/built-in.o.new
264167 738 888 265793 40e41 fs/ext4/built-in.o.old
$ grep -E "CONFIG_EXT4|CONFIG_PRINTK" .config
# CONFIG_PRINTK is not set
CONFIG_EXT4_FS=y
CONFIG_EXT4_USE_FOR_EXT23=y
CONFIG_EXT4_FS_POSIX_ACL=y
# CONFIG_EXT4_FS_SECURITY is not set
# CONFIG_EXT4_DEBUG is not set
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
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Now we maintain an proper in-order LRU list in ext4 to reclaim entries
from extent status tree when we are under heavy memory pressure. For
keeping this order, a spin lock is used to protect this list. But this
lock burns a lot of CPU time. We can use the following steps to trigger
it.
% cd /dev/shm
% dd if=/dev/zero of=ext4-img bs=1M count=2k
% mkfs.ext4 ext4-img
% mount -t ext4 -o loop ext4-img /mnt
% cd /mnt
% for ((i=0;i<160;i++)); do truncate -s 64g $i; done
% for ((i=0;i<160;i++)); do cp $i /dev/null &; done
% perf record -a -g
% perf report
This commit tries to fix this problem. Now a new member called
i_touch_when is added into ext4_inode_info to record the last access
time for an inode. Meanwhile we never need to keep a proper in-order
LRU list. So this can avoid to burns some CPU time. When we try to
reclaim some entries from extent status tree, we use list_sort() to get
a proper in-order list. Then we traverse this list to discard some
entries. In ext4_sb_info, we use s_es_last_sorted to record the last
time of sorting this list. When we traverse the list, we skip the inode
that is newer than this time, and move this inode to the tail of LRU
list. When the head of the list is newer than s_es_last_sorted, we will
sort the LRU list again.
In this commit, we break the loop if s_extent_cache_cnt == 0 because
that means that all extents in extent status tree have been reclaimed.
Meanwhile in this commit, ext4_es_{un}register_shrinker()'s prototype is
changed to save a local variable in these functions.
Reported-by: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
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If memory allocation in ext4_mb_new_group_pa() is failed,
it returns error code, ext4_mb_new_preallocation() propages it,
but ext4_mb_new_blocks() ignores it.
An observed result was:
- allocation fail means ext4_mb_new_group_pa() does not update
ext4_allocation_context;
- ext4_mb_new_blocks() sets ext4_allocation_request->len (ar->len =
ac->ac_b_ex.fe_len;) to number of blocks preallocated (512) instead
of number of blocks requested (1);
- that activates update cycle in ext4_splice_branch():
for (i = 1; i < blks; i++) <-- blks is 512 instead of 1 here
*(where->p + i) = cpu_to_le32(current_block++);
- it iterates 511 times and corrupts a chunk of memory including inode
structure;
- page fault happens at EXT4_SB(inode->i_sb) in ext4_mark_inode_dirty();
- system hangs with 'scheduling while atomic' BUG.
The patch implements a check for ext4_mb_new_preallocation() error
code and handles its failure as if ext4_mb_regular_allocator() fails.
Found by Linux File System Verification project (linuxtesting.org).
[ Patch restructed by tytso to make the flow of control easier to follow. ]
Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
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Subtracting the number of the first data block places the superblock
backups one block too early, corrupting the file system. When the block
size is larger than 1K, the first data block is 0, so the subtraction
has no effect and no corruption occurs.
Signed-off-by: Maarten ter Huurne <maarten@treewalker.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
CC: stable@vger.kernel.org
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Header size is needed to distinguish between header and the dump data.
Incorporate the addition of new argument (hsize) in the pstore write
callback.
Signed-off-by: Aruna Balakrishnaiah <aruna@linux.vnet.ibm.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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Merge 3.10 in order to get some of the last minute powerpc
changes, resolve conflicts and add additional fixes on top
of them.
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git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull ubifs fixes from Al Viro:
"A couple of ubifs readdir/lseek race fixes. Stable fodder, really
nasty..."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
UBIFS: fix a horrid bug
UBIFS: prepare to fix a horrid bug
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fix from Ingo Molnar:
"One more fix for a recently discovered bug"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf: Disable monitoring on setuid processes for regular users
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Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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There's no reason we have to protect the blocked_hash and file_lock_list
with the same spinlock. With the tests I have, breaking it in two gives
a barely measurable performance benefit, but it seems reasonable to make
this locking as granular as possible.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Currently, the hashing that the locking code uses to add these values
to the blocked_hash is simply calculated using fl_owner field. That's
valid in most cases except for server-side lockd, which validates the
owner of a lock based on fl_owner and fl_pid.
In the case where you have a small number of NFS clients doing a lot
of locking between different processes, you could end up with all
the blocked requests sitting in a very small number of hash buckets.
Add a new lm_owner_key operation to the lock_manager_operations that
will generate an unsigned long to use as the key in the hashtable.
That function is only implemented for server-side lockd, and simply
XORs the fl_owner and fl_pid.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Acked-by: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Break up the blocked_list into a hashtable, using the fl_owner as a key.
This speeds up searching the hash chains, which is especially significant
for deadlock detection.
Note that the initial implementation assumes that hashing on fl_owner is
sufficient. In most cases it should be, with the notable exception being
server-side lockd, which compares ownership using a tuple of the
nlm_host and the pid sent in the lock request. So, this may degrade to a
single hash bucket when you only have a single NFS client. That will be
addressed in a later patch.
The careful observer may note that this patch leaves the file_lock_list
alone. There's much less of a case for turning the file_lock_list into a
hashtable. The only user of that list is the code that generates
/proc/locks, and it always walks the entire list.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Acked-by: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Testing has shown that iterating over the blocked_list for deadlock
detection turns out to be a bottleneck. In order to alleviate that,
begin the process of turning it into a hashtable. We start by turning
the fl_link into a hlist_node and the global lists into hlists. A later
patch will do the conversion of the blocked_list to a hashtable.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Acked-by: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Since we always hold the i_lock when inserting a new waiter onto the
fl_block list, we can avoid taking the global lock at all if we find
that it's empty when we go to wake up blocked waiters.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Having a global lock that protects all of this code is a clear
scalability problem. Instead of doing that, move most of the code to be
protected by the i_lock instead. The exceptions are the global lists
that the ->fl_link sits on, and the ->fl_block list.
->fl_link is what connects these structures to the
global lists, so we must ensure that we hold those locks when iterating
over or updating these lists.
Furthermore, sound deadlock detection requires that we hold the
blocked_list state steady while checking for loops. We also must ensure
that the search and update to the list are atomic.
For the checking and insertion side of the blocked_list, push the
acquisition of the global lock into __posix_lock_file and ensure that
checking and update of the blocked_list is done without dropping the
lock in between.
On the removal side, when waking up blocked lock waiters, take the
global lock before walking the blocked list and dequeue the waiters from
the global list prior to removal from the fl_block list.
With this, deadlock detection should be race free while we minimize
excessive file_lock_lock thrashing.
Finally, in order to avoid a lock inversion problem when handling
/proc/locks output we must ensure that manipulations of the fl_block
list are also protected by the file_lock_lock.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Move the fl_link list handling routines into a separate set of helpers.
Also ensure that locks and requests are always put on global lists
last (after fully initializing them) and are taken off before unintializing
them.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Signed-off-by: Jeff Layton <jlayton@redhat.com>
Acked-by: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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