diff options
author | Michael Pratt <mpratt@google.com> | 2019-04-04 17:13:31 -0700 |
---|---|---|
committer | Shentubot <shentubot@google.com> | 2019-04-04 17:14:27 -0700 |
commit | 75a5ccf5d98876c26305da0feff20e4a148027ec (patch) | |
tree | df7ae64d05c7537108d3d8c278a61da8f394da41 /pkg/sentry | |
parent | 75c8ac38e0f6cc4eb3726c89aee41357cd592c4b (diff) |
Remove defer from trivial ThreadID methods
In particular, ns.IDOfTask and tg.ID are used for gettid and getpid,
respectively, where removing defer saves ~100ns. This may be a small
improvement to application logging, which may call gettid/getpid
frequently.
PiperOrigin-RevId: 242039616
Change-Id: I860beb62db3fe077519835e6bafa7c74cba6ca80
Diffstat (limited to 'pkg/sentry')
-rw-r--r-- | pkg/sentry/kernel/threads.go | 20 |
1 files changed, 12 insertions, 8 deletions
diff --git a/pkg/sentry/kernel/threads.go b/pkg/sentry/kernel/threads.go index 4af1b7dfa..4fd6cf4e2 100644 --- a/pkg/sentry/kernel/threads.go +++ b/pkg/sentry/kernel/threads.go @@ -196,8 +196,9 @@ func (ns *PIDNamespace) NewChild(userns *auth.UserNamespace) *PIDNamespace { // task has that TID, TaskWithID returns nil. func (ns *PIDNamespace) TaskWithID(tid ThreadID) *Task { ns.owner.mu.RLock() - defer ns.owner.mu.RUnlock() - return ns.tasks[tid] + t := ns.tasks[tid] + ns.owner.mu.RUnlock() + return t } // ThreadGroupWithID returns the thread group lead by the task with thread ID @@ -224,16 +225,18 @@ func (ns *PIDNamespace) ThreadGroupWithID(tid ThreadID) *ThreadGroup { // 0. func (ns *PIDNamespace) IDOfTask(t *Task) ThreadID { ns.owner.mu.RLock() - defer ns.owner.mu.RUnlock() - return ns.tids[t] + id := ns.tids[t] + ns.owner.mu.RUnlock() + return id } // IDOfThreadGroup returns the TID assigned to tg's leader in PID namespace ns. // If the task is not visible in that namespace, IDOfThreadGroup returns 0. func (ns *PIDNamespace) IDOfThreadGroup(tg *ThreadGroup) ThreadID { ns.owner.mu.RLock() - defer ns.owner.mu.RUnlock() - return ns.tgids[tg] + id := ns.tgids[tg] + ns.owner.mu.RUnlock() + return id } // Tasks returns a snapshot of the tasks in ns. @@ -390,8 +393,9 @@ func (tg *ThreadGroup) MemberIDs(pidns *PIDNamespace) []ThreadID { // is dead, ID returns 0. func (tg *ThreadGroup) ID() ThreadID { tg.pidns.owner.mu.RLock() - defer tg.pidns.owner.mu.RUnlock() - return tg.pidns.tgids[tg] + id := tg.pidns.tgids[tg] + tg.pidns.owner.mu.RUnlock() + return id } // A taskNode defines the relationship between a task and the rest of the |