Commit Graph

435 Commits

Author SHA1 Message Date
Mateusz Guzik
739ecbcf1c cache: add symlink support to lockless lookup
Reviewed by:	kib (previous version)
Tested by:	pho (previous version)
Differential Revision:	https://reviews.freebsd.org/D27488
2021-01-23 15:04:43 +00:00
Mateusz Guzik
2171b8e8a2 cache: augment sdt probe in cache_fplookup_dot
Same as 6d386b4c ("cache: save a branch in cache_fplookup_next")
2021-01-20 07:23:14 +00:00
Mateusz Guzik
aae03cfe64 cache: whitespace nit in cache_fplookup_modifying 2021-01-20 07:22:04 +00:00
Mateusz Guzik
57dab0292a cache: fix some typos 2021-01-19 10:17:14 +01:00
Mateusz Guzik
84ab77ad27 cache: drop-write only var from cache_fplookup_preparse 2021-01-19 10:13:30 +01:00
Mateusz Guzik
6d386b4c8a cache: save a branch in cache_fplookup_next
Previously the code would branch on top find out whether it should
branch on SDT probe and bumping the numposhits counter, depending
on cache_fplookup_cross_mount.

Arguably it should be done regardless of what said function returns.
2021-01-19 10:08:24 +01:00
Mateusz Guzik
70ba77706d vfs: extend vfs:namei:lookup:return probe with nameidata 2021-01-12 13:35:27 +00:00
Mateusz Guzik
8ddea0b127 cache: just assign ni_resflags = NIRES_ABS
It is guaranteed to be 0 on entry.
2021-01-08 13:57:10 +00:00
Mateusz Guzik
fee405e057 cache: stop checkpointing cn_flags
They are only modified, if ever, for the last component.
2021-01-07 23:29:52 +00:00
Mateusz Guzik
ac7715471c cache: stop checkpointing cn_nameptr
For aborts cn_nameptr is the same as cn_pnbuf. For partial results
the same cn_nameptr is to be used.
2021-01-07 23:29:38 +00:00
Mateusz Guzik
0f1fc3a31f cache: stop manipulating pathlen
It is a copy-pasto from regular lookup. Add debug to ensure the result
is the same.
2021-01-07 23:26:53 +00:00
Mateusz Guzik
f2b794e1e9 cache: unengrish the comment in previous commit
Reported by:	rpokala, brd
2021-01-06 23:46:05 +00:00
Mateusz Guzik
deabdc6868 cache: stop pre-checking seqc when starting the lookup
Tested by:	pho
2021-01-06 07:28:07 +00:00
Mateusz Guzik
71a6a0b545 cache: skip checking for spurious slashes if possible
Tested by:	pho
2021-01-06 07:28:06 +00:00
Mateusz Guzik
33f3e81df5 cache: combine fast path enabled status into one flag
Tested by:	pho
2021-01-06 07:28:06 +00:00
Mateusz Guzik
dbbbc07cc3 cache: split handling of 0 and non-0 error codes
Tested by:	pho
2021-01-06 07:07:24 +01:00
Mateusz Guzik
a1a8f8ada1 cache: deinline state handling
The intent is to reduce branchfest when finishing the lookup.

Tested by:	pho
2021-01-06 07:05:22 +01:00
Mateusz Guzik
05803be000 cache: stop setting cn_nameptr on entry as matches cn_pnbuf already
While here tidy up other asserts.
2021-01-06 07:03:41 +01:00
Mateusz Guzik
3814bea00a cache: drop the now spurious doomed check when crossing a mount point 2021-01-03 21:22:16 +00:00
Mateusz Guzik
82397d7919 vfs: denote vnode being a mount point with VIRF_MOUNTPOINT
Reviewed by:	kib (previous version)
Differential Revision:	https://reviews.freebsd.org/D27794
2021-01-03 06:50:06 +00:00
Mateusz Guzik
51bf55fa6c cache: stop checkpointing cn_namelen
The variable is recomputed by regular lookup from the get go.
2021-01-03 06:50:06 +00:00
Mateusz Guzik
7220a10b5b cache: predict on no spurious slashes in cache_fpl_handle_root
This is a step towards speculatively not handling them.
2021-01-03 06:50:06 +00:00
Mateusz Guzik
30a2fc91fa cache: postpone NAME_MAX check as it may be unnecessary 2021-01-03 06:50:06 +00:00
Mateusz Guzik
eca899bd5d cache: remove spurious null check in sdt probe 2021-01-03 06:50:06 +00:00
Mateusz Guzik
1365b5f86f cache: fold NCF_WHITE check into the rest
Tested by:	pho
2021-01-01 00:10:43 +00:00
Mateusz Guzik
d7c62d98c9 cache: call cache_fplookup_modifying in neg
Tested by:	pho
2021-01-01 00:10:43 +00:00
Mateusz Guzik
6fe7de1a25 cache: refactor cache_fpl_handle_root to fit the rest of the code better
Tested by:	pho
2021-01-01 00:10:43 +00:00
Mateusz Guzik
e17e01bd0e cache: refactor dot handling
Tested by:	pho
2021-01-01 00:10:43 +00:00
Mateusz Guzik
4651db56c7 cache: remove a branch from mount point checking
Tested by:	pho
2021-01-01 00:10:42 +00:00
Mateusz Guzik
0b5bd1afd8 cache: support lockless lookup of degenerate paths
Tested by:	pho
2021-01-01 00:10:42 +00:00
Mateusz Guzik
1d6eb97677 cache: save on branching when parsing the path by inserting a sentinel
Tested by:	pho
2021-01-01 00:10:42 +00:00
Mateusz Guzik
67297766b5 cache: hoist trailing slash and degenerate path handling out of the loop
Tested by:	pho
2021-01-01 00:10:42 +00:00
Mateusz Guzik
0c09f4b0cc cache: work around corner case of dvp == tvp in cache_fplookup_final_modifying
Fixes a panic where the kernel would unlock an unheld lock coming from
rename looking up "foo/." as the source.

Reported by:	markj (syzkaller)
2020-12-28 21:38:20 +00:00
Mateusz Guzik
4ab7d9f484 cache: reduce engrish in previous commit 2020-12-28 02:05:30 +00:00
Mateusz Guzik
0714f921cd cache: save on some branching in common case mount point traversal 2020-12-28 01:53:28 +00:00
Mateusz Guzik
002e18eb7f vfs: add FAILIFEXISTS flag
Both FreeBSD and Linux mkdir -p walk the tree up ignoring any EEXIST on
the way and both are used a lot when building respective kernels.

This poses a problem as spurious locking avoidably interferes with
concurrent operations like getdirentries on affected directories.

Work around the problem by adding FAILIFEXISTS flag. In case of lockless
lookup this manages to avoid any work to begin with, there is no speed
up for the locked case but perhaps this can be augmented later on.

For simplicity the only supported semantics are as used by mkdir.

Reviewed by:	kib (previous version)
Differential Revision:	https://reviews.freebsd.org/D27789
2020-12-28 01:53:27 +00:00
Mateusz Guzik
ff97bc034f cache: simplify lockless dot lookups 2020-12-28 01:53:27 +00:00
Mateusz Guzik
abd7ded451 cache: modification and last entry filling support in lockless lookup v2
The previous patch failed to set the ISDOTDOT flag when appropriate,
which in turn fail to properly handle degenerate lookups.

While here sprinkle some extra assertions.

Tested by:	pho (previous version)
2020-12-27 21:03:18 +00:00
Mateusz Guzik
623daa69f9 cache: assert internal flags are not passed by namei 2020-12-27 19:49:24 +00:00
Mateusz Guzik
a1fc1f10c6 Revert "cache: modification and last entry filling support in lockless lookup"
This reverts commit 6dbb07ed68.

Some ports unreliably fail to build with rmdir getting ENOTEMPTY.
2020-12-27 19:02:29 +00:00
Mateusz Guzik
6dbb07ed68 cache: modification and last entry filling support in lockless lookup
Tested by:	pho (previous version)
2020-12-27 17:22:25 +00:00
Mateusz Guzik
906a73e791 cache: fix up cache_hold_vnode comment 2020-12-23 07:24:29 +00:00
Mateusz Guzik
8ab96e265d cache: fix ups bad predicts
- last level fallback normally sees CREATE; the code should be optimized to not
get there for said case
- fast path commonly fails with ENOENT
2020-12-13 21:29:39 +00:00
Ryan Libby
d3bbf8af68 cache_fplookup: quiet gcc -Wreturn-type
Reviewed by:	markj, mjg
Sponsored by:	Dell EMC Isilon
Differential Revision:	https://reviews.freebsd.org/D27555
2020-12-11 22:51:44 +00:00
Mateusz Guzik
f6dd1aefb7 vfs: group mount per-cpu vars into one struct
While here move frequently read stuff into the same cacheline.

This shrinks struct mount by 64 bytes.

Tested by:	pho
2020-11-09 23:02:13 +00:00
Mateusz Guzik
4bfebc8d2c cache: add cache_vop_mkdir and rename cache_rename to cache_vop_rename 2020-10-30 10:46:35 +00:00
Mateusz Guzik
d681c51d36 cache: add missing NIRES_ABS handling 2020-10-26 18:01:18 +00:00
Mateusz Guzik
eb65cde4f5 cache: assorted typo fixes 2020-10-24 13:31:40 +00:00
Mateusz Guzik
029cfccc71 cache: add the missing NC_NOMAKEENTRY and NC_KEEPPOSENTRY to lockless lookup
They are de facto ignored.
2020-10-24 13:31:25 +00:00
Mateusz Guzik
acb41008f3 cache: batch updates to numcache in case of mass removal 2020-10-24 01:14:52 +00:00