diff --git a/libc/Android.bp b/libc/Android.bp
index 8d0a24b..cafcb91 100644
--- a/libc/Android.bp
+++ b/libc/Android.bp
@@ -1113,6 +1113,7 @@
         "bionic/open.cpp",
         "bionic/pathconf.cpp",
         "bionic/pause.cpp",
+        "bionic/pidfd.cpp",
         "bionic/pipe.cpp",
         "bionic/poll.cpp",
         "bionic/posix_fadvise.cpp",
diff --git a/libc/SECCOMP_ALLOWLIST_COMMON.TXT b/libc/SECCOMP_ALLOWLIST_COMMON.TXT
index 804676e..20c1441 100644
--- a/libc/SECCOMP_ALLOWLIST_COMMON.TXT
+++ b/libc/SECCOMP_ALLOWLIST_COMMON.TXT
@@ -72,5 +72,3 @@
 int rt_sigtimedwait_time64(const sigset64_t*, siginfo_t*, const timespec64*, size_t) lp32
 int futex_time64(int*, int, int, const timespec64*, int*, int) lp32
 int sched_rr_get_interval_time64(pid_t, timespec64*) lp32
-# Since Linux 5.3, not in glibc.
-int pidfd_open(pid_t pid, unsigned int flags) all
diff --git a/libc/SYSCALLS.TXT b/libc/SYSCALLS.TXT
index 33a8a61..d263508 100644
--- a/libc/SYSCALLS.TXT
+++ b/libc/SYSCALLS.TXT
@@ -358,3 +358,8 @@
 
 # <sys/random.h>
 ssize_t getrandom(void*, size_t, unsigned) all
+
+# <sys/pidfd.h>
+int __pidfd_open:pidfd_open(pid_t, unsigned int) all
+int __pidfd_getfd:pidfd_getfd(int, int, unsigned int) all
+int pidfd_send_signal(int, int, siginfo_t*, unsigned int) all
diff --git a/libc/bionic/pidfd.cpp b/libc/bionic/pidfd.cpp
new file mode 100644
index 0000000..1dcb1fd
--- /dev/null
+++ b/libc/bionic/pidfd.cpp
@@ -0,0 +1,42 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/pidfd.h>
+
+#include "private/bionic_fdtrack.h"
+
+extern "C" int __pidfd_open(pid_t pid, unsigned int flags);
+extern "C" int __pidfd_getfd(int pidfd, int targetfd, unsigned int flags);
+
+int pidfd_open(pid_t pid, unsigned int flags) {
+  return FDTRACK_CREATE(__pidfd_open(pid, flags));
+}
+
+int pidfd_getfd(int pidfd, int targetfd, unsigned int flags) {
+  return FDTRACK_CREATE(__pidfd_getfd(pidfd, targetfd, flags));
+}
diff --git a/libc/include/sys/pidfd.h b/libc/include/sys/pidfd.h
new file mode 100644
index 0000000..6d0e809
--- /dev/null
+++ b/libc/include/sys/pidfd.h
@@ -0,0 +1,76 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+#pragma once
+
+/**
+ * @file sys/pidfd.h
+ * @brief File descriptors representing processes.
+ */
+
+#include <sys/cdefs.h>
+#include <sys/types.h>
+
+#include <bits/signal_types.h>
+
+__BEGIN_DECLS
+
+/**
+ * [pidfd_open(2)](https://man7.org/linux/man-pages/man2/pidfd_open.2.html)
+ * opens a file descriptor that refers to a process. This file descriptor will
+ * have the close-on-exec flag set by default.
+ *
+ * Returns a new file descriptor on success and returns -1 and sets `errno` on
+ * failure.
+ *
+ * Available since API level 31.
+ */
+int pidfd_open(pid_t __pid, unsigned int __flags) __INTRODUCED_IN(31);
+
+/**
+ * [pidfd_getfd(2)](https://man7.org/linux/man-pages/man2/pidfd_open.2.html)
+ * dups a file descriptor from another process. This file descriptor will have
+ * the close-on-exec flag set by default.
+ *
+ * Returns a new file descriptor on success and returns -1 and sets `errno` on
+ * failure.
+ *
+ * Available since API level 31.
+ */
+int pidfd_getfd(int __pidfd, int __targetfd, unsigned int __flags) __INTRODUCED_IN(31);
+
+/**
+ * [pidfd_send_signal(2)](https://man7.org/linux/man-pages/man2/pidfd_send_signal.2.html)
+ * sends a signal to another process.
+ *
+ * Returns 0 on success and returns -1 and sets `errno` on failure.
+ *
+ * Available since API level 31.
+ */
+int pidfd_send_signal(int __pidfd, int __sig, siginfo_t *__info, unsigned int __flags) __INTRODUCED_IN(31);
+
+__END_DECLS
diff --git a/libc/libc.map.txt b/libc/libc.map.txt
index f4f35ac..51a1076 100644
--- a/libc/libc.map.txt
+++ b/libc/libc.map.txt
@@ -1558,6 +1558,9 @@
     __libc_register_dynamic_tls_listeners;
     ffsl;
     ffsll;
+    pidfd_getfd;
+    pidfd_open;
+    pidfd_send_signal;
     process_madvise;
 } LIBC_R;