diff options
| author | Christian Brauner <brauner@kernel.org> | 2026-04-27 16:49:01 +0200 |
|---|---|---|
| committer | Christian Brauner <brauner@kernel.org> | 2026-05-11 23:13:01 +0200 |
| commit | e75c21d5ad82def93bc77e9aa41c2212964a8d2f (patch) | |
| tree | d4b6f54356baa327dcd14355520d91ed94d1fa76 /include/linux | |
| parent | 254f49634ee16a731174d2ae34bc50bd5f45e731 (diff) | |
| parent | 36b3306779ea58f994a614b3663a196707a66ce2 (diff) | |
Merge patch series "revamp fs/filesystems.c"
Mateusz Guzik <mjguzik@gmail.com> says:
The file is a mess with a hand-rolled linked list in a desperate need of
a clean up.
The code to emit /proc/filesystems is used frequently because libselinux
reads the file, which in turn is linked into numerous frequently used
programs (even ones you would not suspect, like sed!). In order to
combat that pre-gen the string instead of pointer-chasing and printfing
one by-one.
open+read+close cycle single-threaded (ops/s):
before: 442732
after: 1063462 (+140%)
Additionally scalability is also improved thanks to bypassing ref
maintenance on open/close.
open+read+close cycle with 20 processes (ops/s):
before: 606177
after: 3300576 (+444%)
The main bottleneck afterwards is the spurious lockref trip on open.
* patches from https://patch.msgid.link/20260425220844.1763933-1-mjguzik@gmail.com:
fs: cache the string generated by reading /proc/filesystems
fs: RCU-ify filesystems list
proc: allow to mark /proc files permanent outside of fs/proc/
Link: https://patch.msgid.link/20260425220844.1763933-1-mjguzik@gmail.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/fs.h | 2 | ||||
| -rw-r--r-- | include/linux/proc_fs.h | 12 |
2 files changed, 13 insertions, 1 deletions
diff --git a/include/linux/fs.h b/include/linux/fs.h index 11559c513dfb..c37bb3c7de8b 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2286,7 +2286,7 @@ struct file_system_type { const struct fs_parameter_spec *parameters; void (*kill_sb) (struct super_block *); struct module *owner; - struct file_system_type * next; + struct hlist_node list; struct hlist_head fs_supers; struct lock_class_key s_lock_key; diff --git a/include/linux/proc_fs.h b/include/linux/proc_fs.h index 19d1c5e5f335..d2860c18dca9 100644 --- a/include/linux/proc_fs.h +++ b/include/linux/proc_fs.h @@ -248,4 +248,16 @@ static inline struct pid_namespace *proc_pid_ns(struct super_block *sb) bool proc_ns_file(const struct file *file); +#if defined CONFIG_PROC_FS && !defined MODULE +void impl_proc_make_permanent(struct proc_dir_entry *pde); +#endif + +static inline void proc_make_permanent(struct proc_dir_entry *pde) +{ + /* Don't give matches to modules. */ +#if defined CONFIG_PROC_FS && !defined MODULE + impl_proc_make_permanent(pde); +#endif +} + #endif /* _LINUX_PROC_FS_H */ |