[libc] Implement process_mrelease. #117503

moar55 · 2024-11-24T18:59:23Z

This PR addresses #110124.

github-actions · 2024-11-24T18:59:44Z

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llvmbot · 2024-11-24T19:01:09Z

@llvm/pr-subscribers-libc

Author: Omar Hossam (moar55)

Changes

This PR addresses #110124.

Full diff: https://github.com/llvm/llvm-project/pull/117503.diff

12 Files Affected:

(modified) libc/config/linux/aarch64/entrypoints.txt (+1)
(modified) libc/config/linux/riscv/entrypoints.txt (+1)
(modified) libc/config/linux/x86_64/entrypoints.txt (+1)
(modified) libc/include/sys/syscall.h.def (+7)
(modified) libc/newhdrgen/yaml/sys/mman.yaml (+7)
(modified) libc/spec/linux.td (+6)
(modified) libc/src/sys/mman/CMakeLists.txt (+5)
(modified) libc/src/sys/mman/linux/CMakeLists.txt (+13-1)
(added) libc/src/sys/mman/linux/process_mrelease.cpp (+33)
(added) libc/src/sys/mman/process_mrelease.h (+22)
(modified) libc/test/src/sys/mman/linux/CMakeLists.txt (+16-2)
(added) libc/test/src/sys/mman/linux/process_mrelease_test.cpp (+72)

diff --git a/libc/config/linux/aarch64/entrypoints.txt b/libc/config/linux/aarch64/entrypoints.txt
index 74ca3742977a5f..08b5072499da69 100644
--- a/libc/config/linux/aarch64/entrypoints.txt
+++ b/libc/config/linux/aarch64/entrypoints.txt
@@ -252,6 +252,7 @@ set(TARGET_LIBC_ENTRYPOINTS
     libc.src.sys.mman.munlockall
     libc.src.sys.mman.munmap
     libc.src.sys.mman.remap_file_pages
+    libc.src.sys.mman.process_mrelease
     libc.src.sys.mman.posix_madvise
     libc.src.sys.mman.shm_open
     libc.src.sys.mman.shm_unlink
diff --git a/libc/config/linux/riscv/entrypoints.txt b/libc/config/linux/riscv/entrypoints.txt
index 5419462d4f5b3b..4ea65f76d7948d 100644
--- a/libc/config/linux/riscv/entrypoints.txt
+++ b/libc/config/linux/riscv/entrypoints.txt
@@ -251,6 +251,7 @@ set(TARGET_LIBC_ENTRYPOINTS
     libc.src.sys.mman.munmap
     libc.src.sys.mman.remap_file_pages
     libc.src.sys.mman.posix_madvise
+    libc.src.sys.mman.process_mrelease
     libc.src.sys.mman.shm_open
     libc.src.sys.mman.shm_unlink
 
diff --git a/libc/config/linux/x86_64/entrypoints.txt b/libc/config/linux/x86_64/entrypoints.txt
index 957e28bd66cc4c..d0651c06b930ad 100644
--- a/libc/config/linux/x86_64/entrypoints.txt
+++ b/libc/config/linux/x86_64/entrypoints.txt
@@ -252,6 +252,7 @@ set(TARGET_LIBC_ENTRYPOINTS
     libc.src.sys.mman.munmap
     libc.src.sys.mman.remap_file_pages
     libc.src.sys.mman.posix_madvise
+    libc.src.sys.mman.process_mrelease
     libc.src.sys.mman.shm_open
     libc.src.sys.mman.shm_unlink
 
diff --git a/libc/include/sys/syscall.h.def b/libc/include/sys/syscall.h.def
index 03c19eb0885ed6..11758ea8336ddf 100644
--- a/libc/include/sys/syscall.h.def
+++ b/libc/include/sys/syscall.h.def
@@ -2349,5 +2349,12 @@
 #define SYS_writev __NR_writev
 #endif
 
+#ifdef __NR_process_mrelease
+#define SYS_process_mrelease __NR_process_mrelease
+#endif
+
+#ifdef __NR_pidfd_open
+#define SYS_pidfd_open __NR_pidfd_open
+#endif
 
 #endif // LLVM_LIBC_SYS_SYSCALL_H
diff --git a/libc/newhdrgen/yaml/sys/mman.yaml b/libc/newhdrgen/yaml/sys/mman.yaml
index 962ca3591917f7..dd53eb60d1ec57 100644
--- a/libc/newhdrgen/yaml/sys/mman.yaml
+++ b/libc/newhdrgen/yaml/sys/mman.yaml
@@ -132,3 +132,10 @@ functions:
     return_type: int
     arguments:
       - type: const char *
+  - name: process_mrelease
+    standards:
+      - Linux
+    return_type: int
+    arguments:
+      - type: int
+      - type: unsigned int
diff --git a/libc/spec/linux.td b/libc/spec/linux.td
index 9b5dc8e30c95e4..99e0949a592dfa 100644
--- a/libc/spec/linux.td
+++ b/libc/spec/linux.td
@@ -112,6 +112,12 @@ def Linux : StandardSpec<"Linux"> {
             ArgSpec<IntType>,
             ArgSpec<SizeTType>,
             ArgSpec<IntType>,
+        FunctionSpec<
+          "process_mrelease",
+          RetValSpec<IntType>,
+          [
+            ArgSpec<IntType>,
+            ArgSpec<UnsignedIntType>
           ]
         >,
         FunctionSpec<
diff --git a/libc/src/sys/mman/CMakeLists.txt b/libc/src/sys/mman/CMakeLists.txt
index 4d4c2ad376050e..7d71f14ff8837f 100644
--- a/libc/src/sys/mman/CMakeLists.txt
+++ b/libc/src/sys/mman/CMakeLists.txt
@@ -113,3 +113,8 @@ add_entrypoint_object(
   DEPENDS
     .${LIBC_TARGET_OS}.mremap
 )
+add_entrypoint_object(
+  process_mrelease 
+  ALIAS 
+  DEPENDS
+    .${LIBC_TARGET_OS}.process_mrelease)
diff --git a/libc/src/sys/mman/linux/CMakeLists.txt b/libc/src/sys/mman/linux/CMakeLists.txt
index 89a0ad1527a065..23a8486a9e12dd 100644
--- a/libc/src/sys/mman/linux/CMakeLists.txt
+++ b/libc/src/sys/mman/linux/CMakeLists.txt
@@ -36,7 +36,6 @@ add_entrypoint_object(
     libc.src.__support.OSUtil.osutil
     libc.src.errno.errno
 )
-
 add_entrypoint_object(
   munmap
   SRCS
@@ -214,3 +213,16 @@ add_entrypoint_object(
     libc.src.unistd.unlink
     .shm_common
 )
+
+add_entrypoint_object(
+  process_mrelease
+  SRCS
+    process_mrelease.cpp
+  HDRS
+    ../process_mrelease.h
+  DEPENDS
+    libc.include.signal
+    libc.src.signal.kill
+    libc.include.sys_syscall
+    libc.src.__support.OSUtil.osutil
+    libc.src.errno.errno)
diff --git a/libc/src/sys/mman/linux/process_mrelease.cpp b/libc/src/sys/mman/linux/process_mrelease.cpp
new file mode 100644
index 00000000000000..d71b1289c3e928
--- /dev/null
+++ b/libc/src/sys/mman/linux/process_mrelease.cpp
@@ -0,0 +1,33 @@
+//===---------- Linux implementation of the mrelease function -----------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "src/sys/mman/process_mrelease.h"
+
+#include "src/__support/OSUtil/syscall.h" // For internal syscall function.
+#include "src/__support/common.h"
+
+#include "src/__support/macros/config.h"
+#include "src/errno/libc_errno.h"
+#include <linux/param.h> // For EXEC_PAGESIZE.
+#include <sys/syscall.h> // For syscall numbers.
+
+namespace LIBC_NAMESPACE_DECL {
+
+LLVM_LIBC_FUNCTION(int, process_mrelease, (int pidfd, unsigned int flags)) {
+  long ret =
+      LIBC_NAMESPACE::syscall_impl<int>(SYS_process_mrelease, pidfd, flags);
+
+  if (ret < 0) {
+    libc_errno = static_cast<int>(-ret);
+    return libc_errno;
+  }
+
+  return 0;
+}
+
+} // namespace LIBC_NAMESPACE_DECL
diff --git a/libc/src/sys/mman/process_mrelease.h b/libc/src/sys/mman/process_mrelease.h
new file mode 100644
index 00000000000000..13a9ba57eae19b
--- /dev/null
+++ b/libc/src/sys/mman/process_mrelease.h
@@ -0,0 +1,22 @@
+//===-- Implementation header for process_mrelease  function -----------------*-
+// C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_SRC_SYS_MMAN_PROCESS_MRELEASE_H
+#define LLVM_LIBC_SRC_SYS_MMAN_PROCESS_MRELEASE_H
+
+#include "src/__support/macros/config.h"
+#include <sys/mman.h> // For size_t and off_t
+
+namespace LIBC_NAMESPACE_DECL {
+
+int process_mrelease(int pidfd, unsigned int flags);
+
+} // namespace LIBC_NAMESPACE_DECL
+
+#endif // LLVM_LIBC_SRC_SYS_MMAN_PROCESS_MRELEASE_H
diff --git a/libc/test/src/sys/mman/linux/CMakeLists.txt b/libc/test/src/sys/mman/linux/CMakeLists.txt
index 44ed11aadfe8b7..87fcc8a25812b9 100644
--- a/libc/test/src/sys/mman/linux/CMakeLists.txt
+++ b/libc/test/src/sys/mman/linux/CMakeLists.txt
@@ -1,5 +1,3 @@
-add_custom_target(libc_sys_mman_unittests)
-
 add_libc_unittest(
   mmap_test
   SUITE
@@ -181,3 +179,19 @@ add_libc_unittest(
     libc.hdr.fcntl_macros
     libc.test.UnitTest.ErrnoSetterMatcher
 )
+
+add_libc_unittest(
+  process_mrelease_test
+  SUITE
+    libc_sys_mman_unittests
+  SRCS
+    process_mrelease_test.cpp
+  DEPENDS
+    libc.include.sys_mman
+    libc.include.sys_syscall
+    libc.src.errno.errno
+    libc.src.sys.mman.process_mrelease
+    libc.src.unistd.close
+    libc.src.stdlib.exit
+    libc.src.__support.OSUtil.osutil
+    libc.src.__support.threads.sleep)
diff --git a/libc/test/src/sys/mman/linux/process_mrelease_test.cpp b/libc/test/src/sys/mman/linux/process_mrelease_test.cpp
new file mode 100644
index 00000000000000..aa47b1ebf9fdcf
--- /dev/null
+++ b/libc/test/src/sys/mman/linux/process_mrelease_test.cpp
@@ -0,0 +1,72 @@
+//===-- Unittests for process_mrelease
+//-------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+#include "src/__support/OSUtil/syscall.h" // For internal syscall function.
+#include "src/__support/threads/sleep.h"
+#include "src/errno/libc_errno.h"
+#include "src/signal/kill.h"
+#include "src/stdlib/exit.h"
+#include "src/sys/mman/process_mrelease.h"
+#include "src/unistd/close.h"
+#include "src/unistd/fork.h"
+#include "test/UnitTest/LibcTest.h"
+
+#include <sys/syscall.h>
+
+int pidfd_open(pid_t pid, unsigned int flags) {
+  return LIBC_NAMESPACE::syscall_impl(SYS_pidfd_open, pid, flags);
+}
+
+TEST(LlvmLibcMProcessMReleaseTest, NoError) {
+  pid_t child_pid = fork();
+  EXPECT_GE(child_pid, 0);
+
+  if (child_pid == 0) {
+    // Child process: wait a bit then exit gracefully.
+    LIBC_NAMESPACE::sleep_briefly();
+    LIBC_NAMESPACE::exit(0);
+  } else {
+    // Parent process: wait a bit and then kill the child.
+    // Give child process some time to start.
+    LIBC_NAMESPACE::sleep_briefly();
+    int pidfd = pidfd_open(child_pid, 0);
+    EXPECT_GE(pidfd, 0);
+
+    // Send SIGKILL to child process
+    LIBC_NAMESPACE::kill(child_pid, SIGKILL);
+
+    EXPECT_EQ(LIBC_NAMESPACE::process_mrelease(pidfd, 0), 0);
+
+    LIBC_NAMESPACE::close(pidfd);
+  }
+}
+
+TEST(LlvmLibcMProcessMReleaseTest, ErrorNotKilled) {
+  pid_t child_pid = fork();
+  EXPECT_GE(child_pid, 0);
+
+  if (child_pid == 0) {
+    // Child process: wait a bit then exit gracefully.
+    LIBC_NAMESPACE::sleep_briefly();
+    LIBC_NAMESPACE::exit(0);
+  } else {
+    // Give child process some time to start.
+    LIBC_NAMESPACE::sleep_briefly();
+    int pidfd = pidfd_open(child_pid, 0);
+    EXPECT_GE(pidfd, 0);
+
+    ASSERT_EQ(LIBC_NAMESPACE::process_mrelease(pidfd, 0), EINVAL);
+
+    LIBC_NAMESPACE::close(pidfd);
+  }
+}
+
+TEST(LlvmLibcMProcessMReleaseTest, ErrorNonExistingPidfd) {
+
+  ASSERT_EQ(LIBC_NAMESPACE::process_mrelease(12345, 0), EBADF);
+}

moar55 · 2024-11-25T09:00:59Z

Hey @SchrodingerZhu can you assign a CO(if you aren't already) to view my PR :)

libc/src/sys/mman/linux/process_mrelease.cpp

libc/src/sys/mman/process_mrelease.h

libc/test/src/sys/mman/linux/process_mrelease_test.cpp

SchrodingerZhu

LGTM. Thank you for the patch!

github-actions · 2024-11-26T22:40:25Z

@moar55 Congratulations on having your first Pull Request (PR) merged into the LLVM Project!

Your changes will be combined with recent changes from other authors, then tested by our build bots. If there is a problem with a build, you may receive a report in an email or a comment on this PR.

Please check whether problems have been caused by your change specifically, as the builds can include changes from many authors. It is not uncommon for your change to be included in a build that fails due to someone else's changes, or infrastructure issues.

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If you don't get any reports, no action is required from you. Your changes are working as expected, well done!

llvm-ci · 2024-11-26T22:42:36Z

LLVM Buildbot has detected a new failure on builder libc-aarch64-ubuntu-dbg running on libc-aarch64-ubuntu while building libc at step 4 "annotate".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/104/builds/11392