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| author | Gabriel Krisman Bertazi <krisman@collabora.com> | 2021-10-25 22:27:34 +0300 |
|---|---|---|
| committer | Jan Kara <jack@suse.cz> | 2021-10-27 13:35:05 +0300 |
| commit | 734a1a5eccc5f7473002b0669f788e135f1f64aa (patch) | |
| tree | 9a2bf10a36c11cd378181c3cefba5440391715a5 /fs/notify/fanotify/fanotify_user.c | |
| parent | 8d11a4f43ef4679be0908026907a7613b33d7127 (diff) | |
| download | linux-734a1a5eccc5f7473002b0669f788e135f1f64aa.tar.xz | |
fanotify: Pre-allocate pool of error events
Pre-allocate slots for file system errors to have greater chances of
succeeding, since error events can happen in GFP_NOFS context. This
patch introduces a group-wide mempool of error events, shared by all
FAN_FS_ERROR marks in this group.
Link: https://lore.kernel.org/r/20211025192746.66445-20-krisman@collabora.com
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Diffstat (limited to 'fs/notify/fanotify/fanotify_user.c')
| -rw-r--r-- | fs/notify/fanotify/fanotify_user.c | 26 |
1 files changed, 25 insertions, 1 deletions
diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c index 66ee3c2805c7..2f4182b754b2 100644 --- a/fs/notify/fanotify/fanotify_user.c +++ b/fs/notify/fanotify/fanotify_user.c @@ -30,6 +30,7 @@ #define FANOTIFY_DEFAULT_MAX_EVENTS 16384 #define FANOTIFY_OLD_DEFAULT_MAX_MARKS 8192 #define FANOTIFY_DEFAULT_MAX_GROUPS 128 +#define FANOTIFY_DEFAULT_FEE_POOL_SIZE 32 /* * Legacy fanotify marks limits (8192) is per group and we introduced a tunable @@ -1054,6 +1055,15 @@ out_dec_ucounts: return ERR_PTR(ret); } +static int fanotify_group_init_error_pool(struct fsnotify_group *group) +{ + if (mempool_initialized(&group->fanotify_data.error_events_pool)) + return 0; + + return mempool_init_kmalloc_pool(&group->fanotify_data.error_events_pool, + FANOTIFY_DEFAULT_FEE_POOL_SIZE, + sizeof(struct fanotify_error_event)); +} static int fanotify_add_mark(struct fsnotify_group *group, fsnotify_connp_t *connp, unsigned int type, @@ -1062,6 +1072,7 @@ static int fanotify_add_mark(struct fsnotify_group *group, { struct fsnotify_mark *fsn_mark; __u32 added; + int ret = 0; mutex_lock(&group->mark_mutex); fsn_mark = fsnotify_find_mark(connp, group); @@ -1072,13 +1083,26 @@ static int fanotify_add_mark(struct fsnotify_group *group, return PTR_ERR(fsn_mark); } } + + /* + * Error events are pre-allocated per group, only if strictly + * needed (i.e. FAN_FS_ERROR was requested). + */ + if (!(flags & FAN_MARK_IGNORED_MASK) && (mask & FAN_FS_ERROR)) { + ret = fanotify_group_init_error_pool(group); + if (ret) + goto out; + } + added = fanotify_mark_add_to_mask(fsn_mark, mask, flags); if (added & ~fsnotify_conn_mask(fsn_mark->connector)) fsnotify_recalc_mask(fsn_mark->connector); + +out: mutex_unlock(&group->mark_mutex); fsnotify_put_mark(fsn_mark); - return 0; + return ret; } static int fanotify_add_vfsmount_mark(struct fsnotify_group *group, |