diff options
| author | Kelly Rossmoyer <krossmo@google.com> | 2017-10-19 13:24:10 -0700 |
|---|---|---|
| committer | Michael Bestas <mkbestas@lineageos.org> | 2019-12-23 23:43:35 +0200 |
| commit | 522411c567b9cfe07ff3c140155293dbdd005567 (patch) | |
| tree | cd20d2a8baf099e01778af0b2a2ca976cfd19050 | |
| parent | bdcb541ec0aaca12acf676fafe1050c298db4b38 (diff) | |
fs: Improve eventpoll logging to stop indicting timerfd
timerfd doesn't create any wakelocks; eventpoll can, and is creating the
wakelocks we see called "[timerfd]". eventpoll creates two kinds of
wakelocks: a single top-level lock associated with the eventpoll fd
itself, and one additional lock for each fd it is polling that needs such
a lock (e.g. those using EPOLLWAKEUP). Current code names the per-fd
locks using the undecorated names of the fds' associated files (hence
"[timerfd]"), and is naming the top-level lock after the PID of the caller
and the name of the file behind the first fd for which a per-fd lock is
created. To make things clearer, the top-level lock is now named using
the caller PID and an "epollfd" designation, while the per-fd locks are
also named with the caller's PID (to associate them with the top-level
lock) and their respective fds' file names.
Bug: 63622255
Bug: 38042165
Test: Ran on device and observed new wakelock naming in bugreport, dumpsys
batterystats, /d/tracing/trace, and d/wakeup_reasons.
Change-Id: I32bfe5fe6766bb569329a450cc7163d52d59ed34
Signed-off-by: Kelly Rossmoyer <krossmo@google.com>
| -rw-r--r-- | fs/eventpoll.c | 14 | ||||
| -rw-r--r-- | fs/timerfd.c | 12 |
2 files changed, 21 insertions, 5 deletions
diff --git a/fs/eventpoll.c b/fs/eventpoll.c index df21fc0cda2b..85e0470f531c 100644 --- a/fs/eventpoll.c +++ b/fs/eventpoll.c @@ -1237,17 +1237,23 @@ static int ep_create_wakeup_source(struct epitem *epi) { const char *name; struct wakeup_source *ws; + char task_comm_buf[TASK_COMM_LEN]; + char buf[64]; + + get_task_comm(task_comm_buf, current); - name = epi->ffd.file->f_path.dentry->d_name.name; if (!epi->ep->ws) { - char buf[64]; - snprintf(buf, sizeof(buf), "eventpoll pid:%d file:%s", current->pid, name); + snprintf(buf, sizeof(buf), "epoll_%.*s_epollfd", + (int)sizeof(task_comm_buf), task_comm_buf); epi->ep->ws = wakeup_source_register(buf); if (!epi->ep->ws) return -ENOMEM; } - ws = wakeup_source_register(name); + name = epi->ffd.file->f_path.dentry->d_name.name; + snprintf(buf, sizeof(buf), "epoll_%.*s_file:%s", + (int)sizeof(task_comm_buf), task_comm_buf, name); + ws = wakeup_source_register(buf); if (!ws) return -ENOMEM; diff --git a/fs/timerfd.c b/fs/timerfd.c index 1327a02ec778..0274ae2f53e6 100644 --- a/fs/timerfd.c +++ b/fs/timerfd.c @@ -44,6 +44,8 @@ struct timerfd_ctx { bool might_cancel; }; +static atomic_t instance_count = ATOMIC_INIT(0); + static LIST_HEAD(cancel_list); static DEFINE_SPINLOCK(cancel_lock); @@ -387,6 +389,9 @@ SYSCALL_DEFINE2(timerfd_create, int, clockid, int, flags) { int ufd; struct timerfd_ctx *ctx; + char task_comm_buf[TASK_COMM_LEN]; + char file_name_buf[32]; + int instance; /* Check the TFD_* constants for consistency. */ BUILD_BUG_ON(TFD_CLOEXEC != O_CLOEXEC); @@ -418,7 +423,12 @@ SYSCALL_DEFINE2(timerfd_create, int, clockid, int, flags) ctx->moffs = ktime_mono_to_real((ktime_t){ .tv64 = 0 }); - ufd = anon_inode_getfd("[timerfd]", &timerfd_fops, ctx, + instance = atomic_inc_return(&instance_count); + get_task_comm(task_comm_buf, current); + snprintf(file_name_buf, sizeof(file_name_buf), "[timerfd%d_%.*s]", + instance, (int)sizeof(task_comm_buf), task_comm_buf); + + ufd = anon_inode_getfd(file_name_buf, &timerfd_fops, ctx, O_RDWR | (flags & TFD_SHARED_FCNTL_FLAGS)); if (ufd < 0) kfree(ctx); |