[PATCH 1/2] nptl: Replace futex_lock_pi with __futex_lock_pi64

Adhemerval Zanella adhemerval.zanella@linaro.org
Thu Oct 29 19:42:07 GMT 2020


And also move __futex_lock_pi64 to futex-internal.c, it decreases the
libpthread code since there is no much gain in optimizing the slow
path.

Checked on x86_64-linux-gnu and i686-linux-gnu.
---
 nptl/pthread_mutex_lock.c      |  3 +-
 nptl/pthread_mutex_timedlock.c |  2 +-
 sysdeps/nptl/futex-internal.c  | 45 +++++++++++++++++++++
 sysdeps/nptl/futex-internal.h  | 74 +---------------------------------
 4 files changed, 49 insertions(+), 75 deletions(-)

diff --git a/nptl/pthread_mutex_lock.c b/nptl/pthread_mutex_lock.c
index 7858abd528..8b6bf45795 100644
--- a/nptl/pthread_mutex_lock.c
+++ b/nptl/pthread_mutex_lock.c
@@ -416,8 +416,7 @@ __pthread_mutex_lock_full (pthread_mutex_t *mutex)
 	    int private = (robust
 			   ? PTHREAD_ROBUST_MUTEX_PSHARED (mutex)
 			   : PTHREAD_MUTEX_PSHARED (mutex));
-	    int e = futex_lock_pi ((unsigned int *) &mutex->__data.__lock,
-				   NULL, private);
+	    int e = __futex_lock_pi64 (&mutex->__data.__lock, NULL, private);
 	    if (e == ESRCH || e == EDEADLK)
 	      {
 		assert (e != EDEADLK
diff --git a/nptl/pthread_mutex_timedlock.c b/nptl/pthread_mutex_timedlock.c
index fe9e651f6c..d839e6862f 100644
--- a/nptl/pthread_mutex_timedlock.c
+++ b/nptl/pthread_mutex_timedlock.c
@@ -378,7 +378,7 @@ __pthread_mutex_clocklock_common (pthread_mutex_t *mutex,
 	    int private = (robust
 			   ? PTHREAD_ROBUST_MUTEX_PSHARED (mutex)
 			   : PTHREAD_MUTEX_PSHARED (mutex));
-	    int e = futex_lock_pi64 (&mutex->__data.__lock, abstime, private);
+	    int e = __futex_lock_pi64 (&mutex->__data.__lock, abstime, private);
 	    if (e == ETIMEDOUT)
 	      return ETIMEDOUT;
 	    else if (e == ESRCH || e == EDEADLK)
diff --git a/sysdeps/nptl/futex-internal.c b/sysdeps/nptl/futex-internal.c
index 457cd3cd69..87de7e2fac 100644
--- a/sysdeps/nptl/futex-internal.c
+++ b/sysdeps/nptl/futex-internal.c
@@ -268,3 +268,48 @@ __futex_clock_wait_bitset64 (int *futexp, int val, clockid_t clockid,
 #endif
   return ret;
 }
+
+int
+__futex_lock_pi64 (int *futex_word, const struct __timespec64 *abstime,
+		   int private)
+{
+  int err = INTERNAL_SYSCALL_CALL (futex_time64, futex_word,
+                                   __lll_private_flag
+                                   (FUTEX_LOCK_PI, private), 0, abstime);
+#ifndef __ASSUME_TIME64_SYSCALLS
+  if (err == -ENOSYS)
+    {
+      if (abstime != NULL && ! in_time_t_range (abstime->tv_sec))
+        return EOVERFLOW;
+
+      struct timespec ts32;
+      if (abstime != NULL)
+        ts32 = valid_timespec64_to_timespec (*abstime);
+
+      err = INTERNAL_SYSCALL_CALL (futex, futex_word, __lll_private_flag
+                                   (FUTEX_LOCK_PI, private), 0,
+                                   abstime != NULL ? &ts32 : NULL);
+    }
+#endif
+  switch (err)
+    {
+    case 0:
+    case -EAGAIN:
+    case -EINTR:
+    case -ETIMEDOUT:
+    case -ESRCH:
+    case -EDEADLK:
+    case -EINVAL: /* This indicates either state corruption or that the kernel
+		     found a waiter on futex address which is waiting via
+		     FUTEX_WAIT or FUTEX_WAIT_BITSET.  This is reported on
+		     some futex_lock_pi usage (pthread_mutex_timedlock for
+		     instance).  */
+      return -err;
+
+    case -EFAULT: /* Must have been caused by a glibc or application bug.  */
+    case -ENOSYS: /* Must have been caused by a glibc bug.  */
+    /* No other errors are documented at this time.  */
+    default:
+      futex_fatal_error ();
+    }
+}
diff --git a/sysdeps/nptl/futex-internal.h b/sysdeps/nptl/futex-internal.h
index cd356e4fa8..f0e3c1458a 100644
--- a/sysdeps/nptl/futex-internal.h
+++ b/sysdeps/nptl/futex-internal.h
@@ -409,78 +409,8 @@ futex_wake (unsigned int* futex_word, int processes_to_wake, int private)
        futex.
      - ETIMEDOUT if the ABSTIME expires.
 */
-static __always_inline int
-futex_lock_pi (unsigned int *futex_word, const struct timespec *abstime,
-	       int private)
-{
-  int err = lll_futex_timed_lock_pi (futex_word, abstime, private);
-  switch (err)
-    {
-    case 0:
-    case -EAGAIN:
-    case -EINTR:
-    case -ETIMEDOUT:
-    case -ESRCH:
-    case -EDEADLK:
-    case -EINVAL: /* This indicates either state corruption or that the kernel
-		     found a waiter on futex address which is waiting via
-		     FUTEX_WAIT or FUTEX_WAIT_BITSET.  This is reported on
-		     some futex_lock_pi usage (pthread_mutex_timedlock for
-		     instance).  */
-      return -err;
-
-    case -EFAULT: /* Must have been caused by a glibc or application bug.  */
-    case -ENOSYS: /* Must have been caused by a glibc bug.  */
-    /* No other errors are documented at this time.  */
-    default:
-      futex_fatal_error ();
-    }
-}
-
-static __always_inline int
-futex_lock_pi64 (int *futex_word, const struct __timespec64 *abstime,
-                 int private)
-{
-  int err = INTERNAL_SYSCALL_CALL (futex_time64, futex_word,
-                                   __lll_private_flag
-                                   (FUTEX_LOCK_PI, private), 0, abstime);
-#ifndef __ASSUME_TIME64_SYSCALLS
-  if (err == -ENOSYS)
-    {
-      if (abstime != NULL && ! in_time_t_range (abstime->tv_sec))
-        return EOVERFLOW;
-
-      struct timespec ts32;
-      if (abstime != NULL)
-        ts32 = valid_timespec64_to_timespec (*abstime);
-
-      err = INTERNAL_SYSCALL_CALL (futex, futex_word, __lll_private_flag
-                                   (FUTEX_LOCK_PI, private), 0,
-                                   abstime != NULL ? &ts32 : NULL);
-    }
-#endif
-  switch (err)
-    {
-    case 0:
-    case -EAGAIN:
-    case -EINTR:
-    case -ETIMEDOUT:
-    case -ESRCH:
-    case -EDEADLK:
-    case -EINVAL: /* This indicates either state corruption or that the kernel
-		     found a waiter on futex address which is waiting via
-		     FUTEX_WAIT or FUTEX_WAIT_BITSET.  This is reported on
-		     some futex_lock_pi usage (pthread_mutex_timedlock for
-		     instance).  */
-      return -err;
-
-    case -EFAULT: /* Must have been caused by a glibc or application bug.  */
-    case -ENOSYS: /* Must have been caused by a glibc bug.  */
-    /* No other errors are documented at this time.  */
-    default:
-      futex_fatal_error ();
-    }
-}
+int __futex_lock_pi64 (int *futex_word, const struct __timespec64 *abstime,
+		       int private) attribute_hidden;
 
 /* Wakes the top priority waiter that called a futex_lock_pi operation on
    the futex.
-- 
2.25.1



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