[PATCH v2 07/14] LoongArch: Atomic and Locking Routines

[caiyinyu <caiyinyu@loongson.cn>]

This patch implements various atomic and locking routines on LoongArch.
---
 .../loongarch/nptl/bits/pthreadtypes-arch.h   |  41 ++++
 sysdeps/loongarch/nptl/bits/semaphore.h       |  32 +++
 sysdeps/loongarch/nptl/libc-lowlevellock.c    |   8 +
 .../sysv/linux/loongarch/atomic-machine.h     | 196 ++++++++++++++++++
 4 files changed, 277 insertions(+)
 create mode 100644 sysdeps/loongarch/nptl/bits/pthreadtypes-arch.h
 create mode 100644 sysdeps/loongarch/nptl/bits/semaphore.h
 create mode 100644 sysdeps/loongarch/nptl/libc-lowlevellock.c
 create mode 100644 sysdeps/unix/sysv/linux/loongarch/atomic-machine.h

diff --git a/sysdeps/loongarch/nptl/bits/pthreadtypes-arch.h b/sysdeps/loongarch/nptl/bits/pthreadtypes-arch.h
new file mode 100644
index 0000000000..e57f122a98
--- /dev/null
+++ b/sysdeps/loongarch/nptl/bits/pthreadtypes-arch.h
@@ -0,0 +1,41 @@
+/* Machine-specific pthread type layouts.
+   Copyright (C) 2021 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library.  If not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#ifndef _BITS_PTHREADTYPES_ARCH_H
+#define _BITS_PTHREADTYPES_ARCH_H 1
+
+#include <bits/endian.h>
+
+#ifdef __loongarch_lp64
+#define __SIZEOF_PTHREAD_ATTR_T 56
+#define __SIZEOF_PTHREAD_MUTEX_T 40
+#define __SIZEOF_PTHREAD_MUTEXATTR_T 4
+#define __SIZEOF_PTHREAD_COND_T 48
+#define __SIZEOF_PTHREAD_CONDATTR_T 4
+#define __SIZEOF_PTHREAD_RWLOCK_T 56
+#define __SIZEOF_PTHREAD_RWLOCKATTR_T 8
+#define __SIZEOF_PTHREAD_BARRIER_T 32
+#define __SIZEOF_PTHREAD_BARRIERATTR_T 4
+#else
+#error "32bit LoongArch systems are not supported"
+#endif
+
+#define __LOCK_ALIGNMENT
+#define __ONCE_ALIGNMENT
+
+#endif /* bits/pthreadtypes.h */
diff --git a/sysdeps/loongarch/nptl/bits/semaphore.h b/sysdeps/loongarch/nptl/bits/semaphore.h
new file mode 100644
index 0000000000..510f3b0e9a
--- /dev/null
+++ b/sysdeps/loongarch/nptl/bits/semaphore.h
@@ -0,0 +1,32 @@
+/* POSIX semaphore type layout
+   Copyright (C) 2021 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library.  If not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#ifndef _SEMAPHORE_H
+#error "Never use <bits/semaphore.h> directly; include <semaphore.h> instead."
+#endif
+
+#define __SIZEOF_SEM_T (4 * __SIZEOF_POINTER__)
+
+/* Value returned if `sem_open' failed.  */
+#define SEM_FAILED ((sem_t *) 0)
+
+typedef union
+{
+  char __size[__SIZEOF_SEM_T];
+  long int __align;
+} sem_t;
diff --git a/sysdeps/loongarch/nptl/libc-lowlevellock.c b/sysdeps/loongarch/nptl/libc-lowlevellock.c
new file mode 100644
index 0000000000..f4b8b5c193
--- /dev/null
+++ b/sysdeps/loongarch/nptl/libc-lowlevellock.c
@@ -0,0 +1,8 @@
+/* This kludge works around a libpthread static linking problem:
+   https://sourceware.org/bugzilla/show_bug.cgi?id=15648.  */
+
+#ifndef SHARED
+#define __lll_lock_wait_private weak_function __lll_lock_wait_private
+#endif
+
+#include <lowlevellock.c>
diff --git a/sysdeps/unix/sysv/linux/loongarch/atomic-machine.h b/sysdeps/unix/sysv/linux/loongarch/atomic-machine.h
new file mode 100644
index 0000000000..dbae608ee5
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/loongarch/atomic-machine.h
@@ -0,0 +1,196 @@
+/* Atomic operations.
+   Copyright (C) 2021 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library.  If not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#ifndef _LINUX_LOONGARCH_BITS_ATOMIC_H
+#define _LINUX_LOONGARCH_BITS_ATOMIC_H 1
+
+#include <stdint.h>
+
+typedef int32_t atomic32_t;
+typedef uint32_t uatomic32_t;
+
+typedef int64_t atomic64_t;
+typedef uint64_t uatomic64_t;
+
+typedef intptr_t atomicptr_t;
+typedef uintptr_t uatomicptr_t;
+typedef intmax_t atomic_max_t;
+typedef uintmax_t uatomic_max_t;
+
+#define atomic_full_barrier() __sync_synchronize ()
+
+#ifdef __LP64__
+#define __HAVE_64B_ATOMICS 1
+#endif
+#define USE_ATOMIC_COMPILER_BUILTINS 1
+#define ATOMIC_EXCHANGE_USES_CAS 0
+
+/* Compare and exchange.
+   For all "bool" routines, we return FALSE if exchange succesful.  */
+
+#define __arch_compare_and_exchange_bool_8_int(mem, newval, oldval, model) \
+  ({ \
+    typeof (*mem) __oldval = (oldval); \
+    !__atomic_compare_exchange_n (mem, (void *) &__oldval, newval, 0, model, \
+				  __ATOMIC_RELAXED); \
+  })
+
+#define __arch_compare_and_exchange_bool_16_int(mem, newval, oldval, model) \
+  ({ \
+    typeof (*mem) __oldval = (oldval); \
+    !__atomic_compare_exchange_n (mem, (void *) &__oldval, newval, 0, model, \
+				  __ATOMIC_RELAXED); \
+  })
+
+#define __arch_compare_and_exchange_bool_32_int(mem, newval, oldval, model) \
+  ({ \
+    typeof (*mem) __oldval = (oldval); \
+    !__atomic_compare_exchange_n (mem, (void *) &__oldval, newval, 0, model, \
+				  __ATOMIC_RELAXED); \
+  })
+
+#define __arch_compare_and_exchange_bool_64_int(mem, newval, oldval, model) \
+  ({ \
+    typeof (*mem) __oldval = (oldval); \
+    !__atomic_compare_exchange_n (mem, (void *) &__oldval, newval, 0, model, \
+				  __ATOMIC_RELAXED); \
+  })
+
+#define __arch_compare_and_exchange_val_8_int(mem, newval, oldval, model) \
+  ({ \
+    typeof (*mem) __oldval = (oldval); \
+    __atomic_compare_exchange_n (mem, (void *) &__oldval, newval, 0, model, \
+				 __ATOMIC_RELAXED); \
+    __oldval; \
+  })
+
+#define __arch_compare_and_exchange_val_16_int(mem, newval, oldval, model) \
+  ({ \
+    typeof (*mem) __oldval = (oldval); \
+    __atomic_compare_exchange_n (mem, (void *) &__oldval, newval, 0, model, \
+				 __ATOMIC_RELAXED); \
+    __oldval; \
+  })
+
+#define __arch_compare_and_exchange_val_32_int(mem, newval, oldval, model) \
+  ({ \
+    typeof (*mem) __oldval = (oldval); \
+    __atomic_compare_exchange_n (mem, (void *) &__oldval, newval, 0, model, \
+				 __ATOMIC_RELAXED); \
+    __oldval; \
+  })
+
+#define __arch_compare_and_exchange_val_64_int(mem, newval, oldval, model) \
+  ({ \
+    typeof (*mem) __oldval = (oldval); \
+    __atomic_compare_exchange_n (mem, (void *) &__oldval, newval, 0, model, \
+				 __ATOMIC_RELAXED); \
+    __oldval; \
+  })
+
+/* Atomic compare and exchange.  */
+
+#define atomic_compare_and_exchange_bool_acq(mem, new, old) \
+  __atomic_bool_bysize (__arch_compare_and_exchange_bool, int, mem, new, old, \
+			__ATOMIC_ACQUIRE)
+
+#define atomic_compare_and_exchange_val_acq(mem, new, old) \
+  __atomic_val_bysize (__arch_compare_and_exchange_val, int, mem, new, old, \
+		       __ATOMIC_ACQUIRE)
+
+#define atomic_compare_and_exchange_val_rel(mem, new, old) \
+  __atomic_val_bysize (__arch_compare_and_exchange_val, int, mem, new, old, \
+		       __ATOMIC_RELEASE)
+
+/* Atomic exchange (without compare).  */
+
+#define __arch_exchange_8_int(mem, newval, model) \
+  __atomic_exchange_n (mem, newval, model)
+
+#define __arch_exchange_16_int(mem, newval, model) \
+  __atomic_exchange_n (mem, newval, model)
+
+#define __arch_exchange_32_int(mem, newval, model) \
+  __atomic_exchange_n (mem, newval, model)
+
+#define __arch_exchange_64_int(mem, newval, model) \
+  __atomic_exchange_n (mem, newval, model)
+
+#define atomic_exchange_acq(mem, value) \
+  __atomic_val_bysize (__arch_exchange, int, mem, value, __ATOMIC_ACQUIRE)
+
+#define atomic_exchange_rel(mem, value) \
+  __atomic_val_bysize (__arch_exchange, int, mem, value, __ATOMIC_RELEASE)
+
+/* Atomically add value and return the previous (unincremented) value.  */
+
+#define __arch_exchange_and_add_8_int(mem, value, model) \
+  __atomic_fetch_add (mem, value, model)
+
+#define __arch_exchange_and_add_16_int(mem, value, model) \
+  __atomic_fetch_add (mem, value, model)
+
+#define __arch_exchange_and_add_32_int(mem, value, model) \
+  __atomic_fetch_add (mem, value, model)
+
+#define __arch_exchange_and_add_64_int(mem, value, model) \
+  __atomic_fetch_add (mem, value, model)
+
+#define atomic_exchange_and_add_acq(mem, value) \
+  __atomic_val_bysize (__arch_exchange_and_add, int, mem, value, \
+		       __ATOMIC_ACQUIRE)
+
+#define atomic_exchange_and_add_rel(mem, value) \
+  __atomic_val_bysize (__arch_exchange_and_add, int, mem, value, \
+		       __ATOMIC_RELEASE)
+
+/* Miscellaneous.  */
+
+#define asm_amo(which, mem, value) \
+  ({ \
+    __atomic_check_size (mem); \
+    typeof (*mem) __tmp; \
+    if (sizeof (__tmp) == 4) \
+      asm volatile(which ".w" \
+			 "\t%0, %z2, %1" \
+		   : "=&r"(__tmp), "+ZB"(*(mem)) \
+		   : "rJ"(value)); \
+    else if (sizeof (__tmp) == 8) \
+      asm volatile(which ".d" \
+			 "\t%0, %z2, %1" \
+		   : "=&r"(__tmp), "+ZB"(*(mem)) \
+		   : "rJ"(value)); \
+    else \
+      abort (); \
+    __tmp; \
+  })
+
+#define atomic_max(mem, value) asm_amo ("ammax_db", mem, value)
+#define atomic_min(mem, value) asm_amo ("ammin_db", mem, value)
+
+#define atomic_bit_test_set(mem, bit) \
+  ({ \
+    typeof (*mem) __mask = (typeof (*mem)) 1 << (bit); \
+    asm_amo ("amor_db", mem, __mask) & __mask; \
+  })
+
+#define catomic_exchange_and_add(mem, value) \
+  atomic_exchange_and_add (mem, value)
+#define catomic_max(mem, value) atomic_max (mem, value)
+
+#endif /* bits/atomic.h */
-- 
2.27.0