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charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Sep 17, 2018 at 6:05 PM nixiaoming wrote: > > In order to identify which thread triggered the event in the > multi-threaded program, add the FAN_EVENT_INFO_TID tag in fanotify_init According to code and man page this is a 'flag' not a 'tag' Please stick to existing terminology. > to select whether to report the event creator's thread id information. > > Signed-off-by: nixiaoming > --- > fs/notify/fanotify/fanotify.c | 5 ++++- > fs/notify/fanotify/fanotify_user.c | 5 +++-- > include/linux/fsnotify_backend.h | 1 + > include/uapi/linux/fanotify.h | 1 + > 4 files changed, 9 insertions(+), 3 deletions(-) > > diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c > index 94b5215..5a3af87 100644 > --- a/fs/notify/fanotify/fanotify.c > +++ b/fs/notify/fanotify/fanotify.c > @@ -171,7 +171,10 @@ struct fanotify_event_info *fanotify_alloc_event(struct fsnotify_group *group, > goto out; > init: __maybe_unused > fsnotify_init_event(&event->fse, inode, mask); > - event->tgid = get_pid(task_tgid(current)); > + if (group->fanotify_data.should_report_tid) > + event->tgid = get_pid(task_pid(current)); > + else > + event->tgid = get_pid(task_tgid(current)); > if (path) { > event->path = *path; > path_get(&event->path); > diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c > index 6905488..3aa425b 100644 > --- a/fs/notify/fanotify/fanotify_user.c > +++ b/fs/notify/fanotify/fanotify_user.c > @@ -693,9 +693,9 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags) > return -EPERM; > > #ifdef CONFIG_AUDITSYSCALL > - if (flags & ~(FAN_ALL_INIT_FLAGS | FAN_ENABLE_AUDIT)) > + if (flags & ~(FAN_ALL_INIT_FLAGS | FAN_ENABLE_AUDIT | FAN_EVENT_INFO_TID)) > #else > - if (flags & ~FAN_ALL_INIT_FLAGS) > + if (flags & ~(FAN_ALL_INIT_FLAGS | FAN_EVENT_INFO_TID)) Not this way. You need to add FAN_EVENT_INFO_TID to FAN_ALL_INIT_FLAGS. > #endif > return -EINVAL; > > @@ -731,6 +731,7 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags) > } > > group->fanotify_data.user = user; > + group->fanotify_data.should_report_tid = (flags & FAN_EVENT_INFO_TID) ? true : false; Please drop "? true : false" its not needed. > atomic_inc(&user->fanotify_listeners); > group->memcg = get_mem_cgroup_from_mm(current->mm); > > diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h > index b8f4182..44c659f 100644 > --- a/include/linux/fsnotify_backend.h > +++ b/include/linux/fsnotify_backend.h > @@ -193,6 +193,7 @@ struct fsnotify_group { > unsigned int max_marks; > struct user_struct *user; > bool audit; > + bool should_report_tid; For brevity I would call that report_tid, but not insisting. > } fanotify_data; > #endif /* CONFIG_FANOTIFY */ > }; > diff --git a/include/uapi/linux/fanotify.h b/include/uapi/linux/fanotify.h > index 7424791..4eba41c 100644 > --- a/include/uapi/linux/fanotify.h > +++ b/include/uapi/linux/fanotify.h > @@ -18,6 +18,7 @@ > > #define FAN_ONDIR 0x40000000 /* event occurred against dir */ > > +#define FAN_EVENT_INFO_TID 0x02000000 /* reports the thread id of the event trigger */ That is not the right place nor the sensible value for this flag, but this: #define FAN_UNLIMITED_QUEUE 0x00000010 #define FAN_UNLIMITED_MARKS 0x00000020 #define FAN_ENABLE_AUDIT 0x00000040 +#define FAN_EVENT_INFO_TID 0x00000080 Thanks, Amir.