svn commit: r363297 - head/sys/kern

[Mateusz Guzik]

Author: mjg
Date: Sat Jul 18 00:14:43 2020
New Revision: 363297
URL: https://svnweb.freebsd.org/changeset/base/363297

Log:
  Short-circuit tdfind when looking for the calling thread.
  
  Common occurence with cpuset and other places.

Modified:
  head/sys/kern/kern_thread.c

Modified: head/sys/kern/kern_thread.c
==============================================================================
--- head/sys/kern/kern_thread.c	Fri Jul 17 23:10:35 2020	(r363296)
+++ head/sys/kern/kern_thread.c	Sat Jul 18 00:14:43 2020	(r363297)
@@ -1299,6 +1299,14 @@ tdfind(lwpid_t tid, pid_t pid)
 	struct thread *td;
 	int run = 0;
 
+	td = curthread;
+	if (td->td_tid == tid) {
+		if (pid != -1 && td->td_proc->p_pid != pid)
+			return (NULL);
+		PROC_LOCK(td->td_proc);
+		return (td);
+	}
+
 	rw_rlock(&tidhash_lock);
 	LIST_FOREACH(td, TIDHASH(tid), td_hash) {
 		if (td->td_tid == tid) {