From: Bart Van Assche <bvanassche@acm.org>
Date: Mon, 15 Feb 2021 02:42:04 +0000 (-0800)
Subject: drd/tests/swapcontext: Add a swapcontext() test
X-Git-Tag: VALGRIND_3_17_0~53
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0062f2b519ea48b82164ae423fac58a59ee00f1a;p=thirdparty%2Fvalgrind.git

drd/tests/swapcontext: Add a swapcontext() test
---

diff --git a/drd/tests/Makefile.am b/drd/tests/Makefile.am
index 5df76150e9..a489c8b46d 100644
--- a/drd/tests/Makefile.am
+++ b/drd/tests/Makefile.am
@@ -267,6 +267,8 @@ EXTRA_DIST =                                        \
 	sem_open_traced.vgtest                      \
 	sem_wait.stderr.exp                         \
 	sem_wait.vgtest                             \
+	swapcontext.stderr.exp                      \
+	swapcontext.vgtest                          \
 	sigalrm.stderr.exp                          \
 	sigalrm.vgtest                              \
 	sigaltstack.stderr.exp                      \
@@ -406,6 +408,7 @@ check_PROGRAMS =      \
   sem_as_mutex        \
   sem_open            \
   sigalrm             \
+  swapcontext         \
   threaded-fork       \
   trylock             \
   unit_bitmap         \
@@ -585,3 +588,5 @@ std_thread2_LDFLAGS          = -Wl,--no-as-needed
 endif
 
 sem_wait_SOURCES            = sem_wait.cpp
+
+swapcontext_SOURCES         = swapcontext.c
diff --git a/drd/tests/swapcontext.c b/drd/tests/swapcontext.c
new file mode 100644
index 0000000000..e73a612dc3
--- /dev/null
+++ b/drd/tests/swapcontext.c
@@ -0,0 +1,124 @@
+/* See also https://bugs.kde.org/show_bug.cgi?id=432381. */
+
+#define _GNU_SOURCE
+
+#include <poll.h>
+#include <pthread.h>
+#include <signal.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/time.h>
+#include <sys/timerfd.h>
+#include <ucontext.h>
+#include <unistd.h>
+#include <valgrind/valgrind.h>
+
+typedef struct thread_local {
+  ucontext_t uc[3];
+  size_t nrsw;
+  int tfd;
+} thread_local_t;
+
+static void f(void *data, int n)
+{
+  enum { NR_SWITCHES = 200000 };
+  struct pollfd pfd;
+  thread_local_t *tlocal = data;
+
+  while (1) {
+    memset(&pfd, 0, sizeof(pfd));
+    pfd.fd = tlocal->tfd;
+    pfd.events = POLLIN;
+
+    if (poll(&pfd, 1, 0) == 1) {
+      if (++tlocal->nrsw == NR_SWITCHES)
+        return;
+      swapcontext(&tlocal->uc[n], &tlocal->uc[3 - n]);
+    }
+  }
+}
+
+void __valgrind_register_current_stack(void)
+{
+  pthread_attr_t attr;
+  size_t stacksize;
+  void *stack;
+
+  if (pthread_getattr_np(pthread_self(), &attr) != 0)
+    abort();
+
+  if (pthread_attr_getstack(&attr, &stack, &stacksize) != 0)
+    abort();
+
+  VALGRIND_STACK_REGISTER(stack, stack + stacksize);
+}
+
+#define STACKSIZE 8192
+
+void *worker(void *data)
+{
+  thread_local_t *tlocal = data;
+  struct itimerspec it;
+
+  __valgrind_register_current_stack();
+
+  tlocal->tfd = timerfd_create(CLOCK_REALTIME, 0);
+  if (tlocal->tfd < 0)
+    abort();
+
+  it.it_interval.tv_sec = 0;
+  it.it_interval.tv_nsec = 1000;
+
+  it.it_value.tv_sec = time(NULL);
+  it.it_value.tv_nsec = 1000;
+
+  if (timerfd_settime(tlocal->tfd, TFD_TIMER_ABSTIME, &it, NULL) < 0)
+    abort();
+
+  if (getcontext(&(tlocal->uc[1])) < 0)
+    abort();
+  if (getcontext(&(tlocal->uc[2])) < 0)
+    abort();
+
+  tlocal->uc[1].uc_link = &tlocal->uc[0];
+  tlocal->uc[1].uc_stack.ss_sp = malloc(STACKSIZE);
+  tlocal->uc[1].uc_stack.ss_size = STACKSIZE;
+  makecontext(&tlocal->uc[1], (void (*)(void))f, 2, tlocal, 1);
+  VALGRIND_STACK_REGISTER(tlocal->uc[1].uc_stack.ss_sp,
+                          tlocal->uc[1].uc_stack.ss_sp +
+                          tlocal->uc[1].uc_stack.ss_size);
+
+  tlocal->uc[2].uc_link = &tlocal->uc[0];
+  tlocal->uc[2].uc_stack.ss_sp = malloc(STACKSIZE);
+  tlocal->uc[2].uc_stack.ss_size = STACKSIZE;
+  makecontext(&tlocal->uc[2], (void (*)(void))f, 2, tlocal, 2);
+  VALGRIND_STACK_REGISTER(tlocal->uc[2].uc_stack.ss_sp,
+                          tlocal->uc[2].uc_stack.ss_sp +
+                          tlocal->uc[2].uc_stack.ss_size);
+
+  swapcontext(&tlocal->uc[0], &tlocal->uc[1]);
+  return NULL;
+}
+
+int main(int argc, char *argv[])
+{
+  enum { NR = 32 };
+  thread_local_t tlocal[NR];
+  pthread_t thread[NR];
+  int i;
+
+  memset(tlocal, 0, sizeof(tlocal));
+
+  for (i = 0; i < NR; i++)
+    pthread_create(&thread[i], NULL, worker, &tlocal[i]);
+
+  // Wait until the threads have been created.
+  sleep(1);
+  for (i = 0; i < NR; i++)
+    pthread_kill(thread[i], SIGINT);
+
+  for (i = 0; i < NR; i++)
+    pthread_join(thread[i], NULL);
+
+  return 0;
+}
diff --git a/drd/tests/swapcontext.stderr.exp b/drd/tests/swapcontext.stderr.exp
new file mode 100644
index 0000000000..1ebc73a407
--- /dev/null
+++ b/drd/tests/swapcontext.stderr.exp
@@ -0,0 +1,7 @@
+
+
+Process terminating with default action of signal 2 (SIGINT)
+   at 0x........: swapcontext (in /...libc...)
+   by 0x........: f (swapcontext.c:?)
+
+ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)
diff --git a/drd/tests/swapcontext.vgtest b/drd/tests/swapcontext.vgtest
new file mode 100644
index 0000000000..98e3712c40
--- /dev/null
+++ b/drd/tests/swapcontext.vgtest
@@ -0,0 +1,4 @@
+prereq: test -e swapcontext && ./supported_libpthread
+vgopts: --read-var-info=yes --check-stack-var=yes --show-confl-seg=no --num-callers=2
+prog: swapcontext
+stderr_filter: filter_stderr