- 01 Nov, 2017 8 commits
-
-
Josef Bacik authored
Right now we do a lot of weird hoops around outstanding_extents in order to keep the extent count consistent. This is because we logically transfer the outstanding_extent count from the initial reservation through the set_delalloc_bits. This makes it pretty difficult to get a handle on how and when we need to mess with outstanding_extents. Fix this by revamping the rules of how we deal with outstanding_extents. Now instead everybody that is holding on to a delalloc extent is required to increase the outstanding extents count for itself. This means we'll have something like this btrfs_delalloc_reserve_metadata - outstanding_extents = 1 btrfs_set_extent_delalloc - outstanding_extents = 2 btrfs_release_delalloc_extents - outstanding_extents = 1 for an initial file write. Now take the append write where we extend an existing delalloc range but still under the maximum extent size btrfs_delalloc_reserve_metadata - outstanding_extents = 2 btrfs_set_extent_delalloc btrfs_set_bit_hook - outstanding_extents = 3 btrfs_merge_extent_hook - outstanding_extents = 2 btrfs_delalloc_release_extents - outstanding_extnets = 1 In order to make the ordered extent transition we of course must now make ordered extents carry their own outstanding_extent reservation, so for cow_file_range we end up with btrfs_add_ordered_extent - outstanding_extents = 2 clear_extent_bit - outstanding_extents = 1 btrfs_remove_ordered_extent - outstanding_extents = 0 This makes all manipulations of outstanding_extents much more explicit. Every successful call to btrfs_delalloc_reserve_metadata _must_ now be combined with btrfs_release_delalloc_extents, even in the error case, as that is the only function that actually modifies the outstanding_extents counter. The drawback to this is now we are much more likely to have transient cases where outstanding_extents is much larger than it actually should be. This could happen before as we manipulated the delalloc bits, but now it happens basically at every write. This may put more pressure on the ENOSPC flushing code, but I think making this code simpler is worth the cost. I have another change coming to mitigate this side-effect somewhat. I also added trace points for the counter manipulation. These were used by a bpf script I wrote to help track down leak issues. Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Zygo Blaxell authored
Build-server workloads have hundreds of references per file after dedup. Multiply by a few snapshots and we quickly exhaust the limit of 2730 references per extent that can fit into a 64K buffer. Raise the limit to 16M to be consistent with other btrfs ioctls (e.g. TREE_SEARCH_V2, FILE_EXTENT_SAME). To minimize surprising userspace behavior, apply this change only to the LOGICAL_INO_V2 ioctl. Signed-off-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org> Reviewed-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com> Tested-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Zygo Blaxell authored
Now that check_extent_in_eb()'s extent offset filter can be turned off, we need a way to do it from userspace. Add a 'flags' field to the btrfs_logical_ino_args structure to disable extent offset filtering, taking the place of one of the existing reserved[] fields. Previous versions of LOGICAL_INO neglected to check whether any of the reserved fields have non-zero values. Assigning meaning to those fields now may change the behavior of existing programs that left these fields uninitialized. The lack of a zero check also means that new programs have no way to know whether the kernel is honoring the flags field. To avoid these problems, define a new ioctl LOGICAL_INO_V2. We can use the same argument layout as LOGICAL_INO, but shorten the reserved[] array by one element and turn it into the 'flags' field. The V2 ioctl explicitly checks that reserved fields and unsupported flag bits are zero so that userspace can negotiate future feature bits as they are defined. Since the memory layouts of the two ioctls' arguments are compatible, there is no need for a separate function for logical_to_ino_v2 (contrast with tree_search_v2 vs tree_search where the layout and code are quite different). A version parameter and an 'if' statement will suffice. Now that we have a flags field in logical_ino_args, add a flag BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET to get the behavior we want, and pass it down the stack to iterate_inodes_from_logical. Motivation and background, copied from the patchset cover letter: Suppose we have a file with one extent: root@tester:~# zcat /usr/share/doc/cpio/changelog.gz > /test/a root@tester:~# sync Split the extent by overwriting it in the middle: root@tester:~# cat /dev/urandom | dd bs=4k seek=2 skip=2 count=1 conv=notrunc of=/test/a We should now have 3 extent refs to 2 extents, with one block unreachable. The extent tree looks like: root@tester:~# btrfs-debug-tree /dev/vdc -t 2 [...] item 9 key (1103101952 EXTENT_ITEM 73728) itemoff 15942 itemsize 53 extent refs 2 gen 29 flags DATA extent data backref root 5 objectid 261 offset 0 count 2 [...] item 11 key (1103175680 EXTENT_ITEM 4096) itemoff 15865 itemsize 53 extent refs 1 gen 30 flags DATA extent data backref root 5 objectid 261 offset 8192 count 1 [...] and the ref tree looks like: root@tester:~# btrfs-debug-tree /dev/vdc -t 5 [...] item 6 key (261 EXTENT_DATA 0) itemoff 15825 itemsize 53 extent data disk byte 1103101952 nr 73728 extent data offset 0 nr 8192 ram 73728 extent compression(none) item 7 key (261 EXTENT_DATA 8192) itemoff 15772 itemsize 53 extent data disk byte 1103175680 nr 4096 extent data offset 0 nr 4096 ram 4096 extent compression(none) item 8 key (261 EXTENT_DATA 12288) itemoff 15719 itemsize 53 extent data disk byte 1103101952 nr 73728 extent data offset 12288 nr 61440 ram 73728 extent compression(none) [...] There are two references to the same extent with different, non-overlapping byte offsets: [------------------72K extent at 1103101952----------------------] [--8K----------------|--4K unreachable----|--60K-----------------] ^ ^ | | [--8K ref offset 0--][--4K ref offset 0--][--60K ref offset 12K--] | v [-----4K extent-----] at 1103175680 We want to find all of the references to extent bytenr 1103101952. Without the patch (and without running btrfs-debug-tree), we have to do it with 18 LOGICAL_INO calls: root@tester:~# btrfs ins log 1103101952 -P /test/ Using LOGICAL_INO inode 261 offset 0 root 5 root@tester:~# for x in $(seq 0 17); do btrfs ins log $((1103101952 + x * 4096)) -P /test/; done 2>&1 | grep inode inode 261 offset 0 root 5 inode 261 offset 4096 root 5 <- same extent ref as offset 0 (offset 8192 returns empty set, not reachable) inode 261 offset 12288 root 5 inode 261 offset 16384 root 5 \ inode 261 offset 20480 root 5 | inode 261 offset 24576 root 5 | inode 261 offset 28672 root 5 | inode 261 offset 32768 root 5 | inode 261 offset 36864 root 5 \ inode 261 offset 40960 root 5 > all the same extent ref as offset 12288. inode 261 offset 45056 root 5 / More processing required in userspace inode 261 offset 49152 root 5 | to figure out these are all duplicates. inode 261 offset 53248 root 5 | inode 261 offset 57344 root 5 | inode 261 offset 61440 root 5 | inode 261 offset 65536 root 5 | inode 261 offset 69632 root 5 / In the worst case the extents are 128MB long, and we have to do 32768 iterations of the loop to find one 4K extent ref. With the patch, we just use one call to map all refs to the extent at once: root@tester:~# btrfs ins log 1103101952 -P /test/ Using LOGICAL_INO_V2 inode 261 offset 0 root 5 inode 261 offset 12288 root 5 The TREE_SEARCH ioctl allows userspace to retrieve the offset and extent bytenr fields easily once the root, inode and offset are known. This is sufficient information to build a complete map of the extent and all of its references. Userspace can use this information to make better choices to dedup or defrag. Signed-off-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org> Reviewed-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com> Tested-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com> [ copy background and motivation from cover letter ] Signed-off-by: David Sterba <dsterba@suse.com>
-
Zygo Blaxell authored
The LOGICAL_INO ioctl provides a backward mapping from extent bytenr and offset (encoded as a single logical address) to a list of extent refs. LOGICAL_INO complements TREE_SEARCH, which provides the forward mapping (extent ref -> extent bytenr and offset, or logical address). These are useful capabilities for programs that manipulate extents and extent references from userspace (e.g. dedup and defrag utilities). When the extents are uncompressed (and not encrypted and not other), check_extent_in_eb performs filtering of the extent refs to remove any extent refs which do not contain the same extent offset as the 'logical' parameter's extent offset. This prevents LOGICAL_INO from returning references to more than a single block. To find the set of extent references to an uncompressed extent from [a, b), userspace has to run a loop like this pseudocode: for (i = a; i < b; ++i) extent_ref_set += LOGICAL_INO(i); At each iteration of the loop (up to 32768 iterations for a 128M extent), data we are interested in is collected in the kernel, then deleted by the filter in check_extent_in_eb. When the extents are compressed (or encrypted or other), the 'logical' parameter must be an extent bytenr (the 'a' parameter in the loop). No filtering by extent offset is done (or possible?) so the result is the complete set of extent refs for the entire extent. This removes the need for the loop, since we get all the extent refs in one call. Add an 'ignore_offset' argument to iterate_inodes_from_logical, [...several levels of function call graph...], and check_extent_in_eb, so that we can disable the extent offset filtering for uncompressed extents. This flag can be set by an improved version of the LOGICAL_INO ioctl to get either behavior as desired. There is no functional change in this patch. The new flag is always false. Signed-off-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org> Reviewed-by: David Sterba <dsterba@suse.com> [ minor coding style fixes ] Signed-off-by: David Sterba <dsterba@suse.com>
-
Nikolay Borisov authored
This code was first introduced in 31db9f7c ("Btrfs: introduce BTRFS_IOC_SEND for btrfs send/receive") and it was not functional, then it got slightly refactored in e938c8ad ("Btrfs: code cleanups for send/receive"), alas it was still dead. So let's remove it for good! Signed-off-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Anand Jain authored
That was only an extra check to tackle a few bugs around this area, now its safe to remove it. Replace it by an ASSERT. Signed-off-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Adam Borowski authored
This is bikeshedding, but it seems people are drastically more likely to understand "zlib:9" as compression level rather than an algorithm version compared to "zlib9". Based on feedback on the mailinglist, the ":9" will be the only accepted syntax. The level must be a single digit. Unrecognized format will result to the default, for forward compatibility in a similar way the compression algorithm specifier was relaxed in commit a7164fa4 ("btrfs: prepare for extensions in compression options"). Signed-off-by: Adam Borowski <kilobyte@angband.pl> Reviewed-by: David Sterba <dsterba@suse.com> [ tighten the accepted format ] Signed-off-by: David Sterba <dsterba@suse.com>
-
David Sterba authored
Preliminary support for setting compression level for zlib, the following works: $ mount -o compess=zlib # default $ mount -o compess=zlib0 # same $ mount -o compess=zlib9 # level 9, slower sync, less data $ mount -o compess=zlib1 # level 1, faster sync, more data $ mount -o remount,compress=zlib3 # level set by remount The compress-force works the same as compress'. The level is visible in the same format in /proc/mounts. Level set via file property does not work yet. Required patch: "btrfs: prepare for extensions in compression options" Signed-off-by: David Sterba <dsterba@suse.com>
-
- 30 Oct, 2017 32 commits
-
-
Nikolay Borisov authored
Currently btrfs' code uses a mix of opencoded sizes and defines from sizes.h. Let's unifiy the code base to always use the symbolic constants. No functional changes Signed-off-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Gu JinXiang authored
Fix missing change from commit f8f84b2d ("btrfs: index check-integrity state hash by a dev_t"). Function btrfsic_dev_state_hashtable_lookup uses dev_t to generate hashval when look in up a btrfsic_dev_state in hash table. So when we add a btrfsic_dev_state into the hash table, it should also use dev_t. Reproducer of this bug: Use MOUNT_OPTIONS="-o check_int" when running xfstest, device can not be mounted successfully. So xfstest can not run. Signed-off-by: Gu JinXiang <gujx@cn.fujitsu.com> Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Anand Jain authored
When one of the device is missing, bbio_error() takes care of setting the error status. And if its only IO that is pending in that stripe, it fails to check the status of the other IO at %bbio_error before setting the error %bi_status for the %orig_bio. Fix this by checking if %bbio->error has exceeded the %bbio->max_errors. Reproducer as below fdatasync error is seen intermittently. mount -o degraded /dev/sdc /btrfs dd status=none if=/dev/zero of=$(mktemp /btrfs/XXX) bs=4096 count=1 conv=fdatasync dd: fdatasync failed for ‘/btrfs/LSe’: Input/output error The reason for the intermittences of the problem is because the following conditions have to be met, which depends on timing: In btrfs_map_bio() - the RAID1 the missing device has to be at %dev_nr = 1 In bbio_error() . before bbio_error() is called the bio of the not-missing device at %dev_nr = 0 must be completed so that the below condition is true if (atomic_dec_and_test(&bbio->stripes_pending)) { Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Anand Jain authored
A cleanup patch, use need_full_stripe() to replace the open code. Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: Qu Wenruo <quwenruo.btrfs@gmx.com> Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Goldwyn Rodrigues authored
Code cleanup for better understanding: Variable needs_unlock to be called extent_locked to show state as opposed to action. Changed the type to int, to reduce code in the critical path. Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Anand Jain authored
At few places we could use BLK_STS_OK and BLK_STS_NOSUPP. Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: Satoru Taekeuchi <satoru.takeuchi@gmail.com> Reviewed-by: David Sterba <dsterba@suse.com> [ dropped first hunk btrfs_endio_direct_read ] Signed-off-by: David Sterba <dsterba@suse.com>
-
Josef Bacik authored
These are useful for debugging problems where we mess with trans->block_rsv to make sure we're not screwing something up. Signed-off-by: Josef Bacik <jbacik@fb.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Josef Bacik authored
We can get this from the ref we've passed in. Signed-off-by: Josef Bacik <jbacik@fb.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Josef Bacik authored
This is just excessive information in the ref_head, and makes the code complicated. It is a relic from when we had the heads and the refs in the same tree, which is no longer the case. With this removal I've cleaned up a bunch of the cruft around this old assumption as well. Signed-off-by: Josef Bacik <jbacik@fb.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Josef Bacik authored
We do a couple different cleanup operations on the ref head. We adjust counters, we'll free any reserved space if we didn't end up using the ref, and we clear the pending csum bytes. Move all these disparate things into cleanup_ref_head and clean up the logic in __btrfs_run_delayed_refs so that it handles the !ref case a lot cleaner, as well as making run_one_delayed_ref() only deal with real refs and not the ref head. Signed-off-by: Josef Bacik <jbacik@fb.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Josef Bacik authored
We only use this logic if our ref isn't a ref_head, so move it up into the if (ref) case since we know that this is a normal ref and not a delayed ref head. Signed-off-by: Josef Bacik <jbacik@fb.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Josef Bacik authored
Move this code out to a helper function to further simplivy __btrfs_run_delayed_refs. Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Josef Bacik authored
Move the extent_op cleanup for an empty head ref to a helper function to help simplify __btrfs_run_delayed_refs. Signed-off-by: Josef Bacik <jbacik@fb.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Josef Bacik authored
Simplify the error handling in __btrfs_run_delayed_refs by breaking out the code used to return a head back to the delayed_refs tree for processing into a helper function. Signed-off-by: Josef Bacik <jbacik@fb.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Josef Bacik authored
We were only doing btrfs_check_space_for_delayed_refs() if the metadata space was full, ie we couldn't allocate chunks. This assumes we'll be able to allocate chunks during transaction commit, but since nothing does a LIMIT flush during the transaction commit this won't actually happen unless we happen to run shy of actual space. We already take into account a full fs in btrfs_check_space_for_delayed_refs() so just kill this extra check to make sure we're ending the transaction when we need to. Signed-off-by: Josef Bacik <jbacik@fb.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Josef Bacik authored
We were having corruption issues that were tied back to problems with the extent tree. In order to track them down I built this tool to try and find the culprit, which was pretty successful. If you compile with this tool on it will live verify every ref update that the fs makes and make sure it is consistent and valid. I've run this through with xfstests and haven't gotten any false positives. Thanks, Signed-off-by: Josef Bacik <jbacik@fb.com> Reviewed-by: David Sterba <dsterba@suse.com> [ update error messages, add fixup from Dan Carpenter to handle errors of read_tree_block ] Signed-off-by: David Sterba <dsterba@suse.com>
-
Josef Bacik authored
We need the actual root for the ref verifier tool to work, so change these functions to pass the root around instead. This will be used in a subsequent patch. Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Josef Bacik authored
This adds the infrastructure for turning ref verify on and off for a mount, to be used by a later patch. Signed-off-by: Josef Bacik <jbacik@fb.com> Reviewed-by: David Sterba <dsterba@suse.com> [ enhnance btrfs_print_mod_info to print if ref-verify is compiled in ] Signed-off-by: David Sterba <dsterba@suse.com>
-
David Sterba authored
The use of sector_t in the callchain of submit_extent_page is not necessary. Switch to u64 and rename the variable and use byte units instead of 512b, ie. dropping the >> 9 shifts and avoiding the con(tro)versions of sector_t. Reviewed-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
David Sterba authored
We're going to remove sector_t and will use 'offset', so this patch frees the name. Reviewed-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
David Sterba authored
The use of sector_t is not necessry, it's just for a warning. Switch to u64 and rename the variable and use byte units instead of 512b, ie. dropping the >> 9 shifts. The messages are adjusted as well. Reviewed-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Josef Bacik authored
We pass in a pointer in our send arg struct, this means the struct size doesn't match with 32bit user space and 64bit kernel space. Fix this by adding a compat mode and doing the appropriate conversion. Signed-off-by: Josef Bacik <jbacik@fb.com> Reviewed-by: David Sterba <dsterba@suse.com> [ move structure to the beginning, next to receive 32bit compat ] Signed-off-by: David Sterba <dsterba@suse.com>
-
Anand Jain authored
When device is missing without the -o degraded option then its an error so report it as an error instead of a warning. And when -o degraded option is provided, log the missing device as warning. Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> [ switch error to bool ] Signed-off-by: David Sterba <dsterba@suse.com>
-
Anand Jain authored
Signed-off-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Anand Jain authored
EIO is only for the IO failure to the device, avoid it. Use ENOENT as that's the closest error code describing what happened. Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> [ update changelog ] Signed-off-by: David Sterba <dsterba@suse.com>
-
Anand Jain authored
add_missing_dev() can return device pointer so that IS_ERR/PTR_ERR can be used to check for the actual error that occurred in the function. Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: Liu Bo <bo.li.liu@oracle.com> [ minor error message adjustment ] Signed-off-by: David Sterba <dsterba@suse.com>
-
Christos Gkekas authored
Remove variables 'start' and 'end', which are set but never used. Signed-off-by: Christos Gkekas <chris.gekas@gmail.com> Reviewed-by: Omar Sandoval <osandov@fb.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Arnd Bergmann authored
We now get a harmless compile-time on 32-bit architectures: fs/btrfs/tree-checker.c: In function 'check_extent_data_item': fs/btrfs/tree-checker.c:189:70: error: format '%lu' expects argument of type 'long unsigned int', but argument 6 has type 'unsigned int' [-Werror=format=] This changes the format string to use %zu instead of %lu for size_t. Fixes: c1f6520bf360 ("btrfs: tree-checker: Enhance output for check_extent_data_item") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Liu Bo authored
Now that we have the combo of flushing twice, which can make sure IO have started since the second flush will wait for page lock which won't be unlocked unless setting page writeback and queuing ordered extents, we don't need %async_submit_draining, %async_delalloc_pages and %nr_async_submits to tell whether the IO has actually started. Moreover, all the flushers in use are followed by functions that wait for ordered extents to complete, so %nr_async_submits, which tracks whether bio's async submit has made progress, doesn't really make sense. However, %async_delalloc_pages is still required by shrink_delalloc() as that function doesn't flush twice in the normal case (just issues a writeback with WB_REASON_FS_FREE_SPACE). Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Liu Bo authored
By setting compression for a defrag task, the task will start IO at the end of defrag. After the combo of filemap_flush(), we've already made sure that dirty pages have made progress via async compress thread because the second filemap_flush() will wait for page lock, which won't be unlocked until those pages have been marked as writeback and ordered extents have been queued. And this is for per-inode defrag, it's not helpful to wait on a global %async_delalloc_pages and %nr_async_submits from fs_info. Although waiting on %nr_async_submits means that all bios are submitted down to per-device schedule IO lists, it doesn't wait for their completions, thus users still need to do fsync/sync to make sure the data is on disk. While with this change, it makes sure that pages are marked with writeback bits and will be submitted asynchronously shortly, therefore, the behavior of defrag option '-c' remains unchanged. Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Liu Bo authored
This was intended to congest higher layers to not send bios, but as 1) the congested bit has been taken by writeback Async bios come from buffered writes and DIO writes. For DIO writes, we want to submit them ASAP, while for buffered writes, writeback uses balance_dirty_pages() to throttle how much dirty pages we can have. 2) and no one is waiting for %nr_async_bios down to zero, Historically, it was introduced along with changes which let checksumming workload spread accross different cpus. And at that time, pdflush was used instead of per-bdi flushing, perhaps pdflush did not have the necessary information for writeback to do throttling. We can safely remove them now. Signed-off-by: Liu Bo <bo.li.liu@oracle.com> [ additional explanation from mails, removed unused variable 'limit' ] Signed-off-by: David Sterba <dsterba@suse.com>
-
Qu Wenruo authored
Output the invalid member name and its bad value, along with its expected value range or alignment. Signed-off-by: Qu Wenruo <quwenruo.btrfs@gmx.com> Signed-off-by: David Sterba <dsterba@suse.com>
-