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CDRIVER-4215 use legacy atomic built-ins on gcc (>= 4.1, < 4.9) #889

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Merged
merged 3 commits into from
Nov 11, 2021
Merged

CDRIVER-4215 use legacy atomic built-ins on gcc (>= 4.1, < 4.9) #889

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4b760d5
enable dynamic CA configuration on RHEL
rcsanchez97 Nov 11, 2021
20b294d
CDRIVER-4215 use legacy atomic built-ins on gcc (>= 4.1, < 4.9)
rcsanchez97 Nov 7, 2021
066e059
Check that 'weak' will succeeded, even if it takes many tries
vector-of-bool Nov 11, 2021
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1 change: 1 addition & 0 deletions .evergreen/run-tests.sh
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Original file line number Diff line number Diff line change
Expand Up @@ -45,6 +45,7 @@ if [ "$SSL" != "nossl" ]; then
sudo cp -v src/libmongoc/tests/x509gen/ca.pem /usr/share/pki/ca-trust-source/anchors/cdriver.crt || true
if [ -f /usr/share/pki/ca-trust-source/anchors/cdriver.crt ]; then
echo "Copying CA certificate to /usr/share/pki/ca-trust-source/anchors... done."
sudo update-ca-trust enable --verbose
sudo update-ca-trust extract --verbose
else
echo "Copying CA certificate to /usr/share/pki/ca-trust-source/anchors... failed."
Expand Down
83 changes: 78 additions & 5 deletions src/libbson/src/bson/bson-atomic.h
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Expand Up @@ -47,42 +47,73 @@ enum bson_memory_order {
#define MSVC_MEMORDER_SUFFIX(X)
#endif

#if defined(USE_LEGACY_GCC_ATOMICS) || (!defined(__clang__) && \
__GNUC__ == 4 && __GNUC_MINOR__ >= 1 && __GNUC_MINOR__ < 9)
#define BSON_USE_LEGACY_GCC_ATOMICS
#else
#undef BSON_USE_LEGACY_GCC_ATOMICS
#endif

/* Not all GCC-like compilers support the current __atomic built-ins. Older
* GCC (pre-4.9) used different built-ins named with the __sync prefix. When
* compiling with such older GCC versions, it is necessary to use the applicable
* functions, which requires redefining BSON_IF_GNU_LIKE and defining the
* additional BSON_IF_GNU_LEGACY_ATOMICS macro here. */
#ifdef BSON_USE_LEGACY_GCC_ATOMICS
#undef BSON_IF_GNU_LIKE
#define BSON_IF_GNU_LIKE(...)
#define BSON_IF_GNU_LEGACY_ATOMICS(...) __VA_ARGS__
#else
#define BSON_IF_GNU_LEGACY_ATOMICS(...)
#endif

#define DEF_ATOMIC_OP(MSVC_Intrinsic, GNU_Intrinsic, Order, ...) \
#define DEF_ATOMIC_OP(MSVC_Intrinsic, GNU_Intrinsic, GNU_Legacy_Intrinsic, Order, ...) \
do { \
switch (Order) { \
case bson_memory_order_acq_rel: \
BSON_IF_MSVC (return MSVC_Intrinsic (__VA_ARGS__);) \
BSON_IF_GNU_LIKE ( \
return GNU_Intrinsic (__VA_ARGS__, __ATOMIC_ACQ_REL);) \
BSON_IF_GNU_LEGACY_ATOMICS ( \
return GNU_Legacy_Intrinsic (__VA_ARGS__);) \
case bson_memory_order_seq_cst: \
BSON_IF_MSVC (return MSVC_Intrinsic (__VA_ARGS__);) \
BSON_IF_GNU_LIKE ( \
return GNU_Intrinsic (__VA_ARGS__, __ATOMIC_SEQ_CST);) \
BSON_IF_GNU_LEGACY_ATOMICS ( \
return GNU_Legacy_Intrinsic (__VA_ARGS__);) \
case bson_memory_order_acquire: \
BSON_IF_MSVC ( \
return BSON_CONCAT (MSVC_Intrinsic, \
MSVC_MEMORDER_SUFFIX (_acq)) (__VA_ARGS__);) \
BSON_IF_GNU_LIKE ( \
return GNU_Intrinsic (__VA_ARGS__, __ATOMIC_ACQUIRE);) \
BSON_IF_GNU_LEGACY_ATOMICS ( \
return GNU_Legacy_Intrinsic (__VA_ARGS__);) \
case bson_memory_order_consume: \
BSON_IF_MSVC ( \
return BSON_CONCAT (MSVC_Intrinsic, \
MSVC_MEMORDER_SUFFIX (_acq)) (__VA_ARGS__);) \
BSON_IF_GNU_LIKE ( \
return GNU_Intrinsic (__VA_ARGS__, __ATOMIC_CONSUME);) \
BSON_IF_GNU_LEGACY_ATOMICS ( \
return GNU_Legacy_Intrinsic (__VA_ARGS__);) \
case bson_memory_order_release: \
BSON_IF_MSVC ( \
return BSON_CONCAT (MSVC_Intrinsic, \
MSVC_MEMORDER_SUFFIX (_rel)) (__VA_ARGS__);) \
BSON_IF_GNU_LIKE ( \
return GNU_Intrinsic (__VA_ARGS__, __ATOMIC_RELEASE);) \
BSON_IF_GNU_LEGACY_ATOMICS ( \
return GNU_Legacy_Intrinsic (__VA_ARGS__);) \
case bson_memory_order_relaxed: \
BSON_IF_MSVC ( \
return BSON_CONCAT (MSVC_Intrinsic, \
MSVC_MEMORDER_SUFFIX (_nf)) (__VA_ARGS__);) \
BSON_IF_GNU_LIKE ( \
return GNU_Intrinsic (__VA_ARGS__, __ATOMIC_RELAXED);) \
BSON_IF_GNU_LEGACY_ATOMICS ( \
return GNU_Legacy_Intrinsic (__VA_ARGS__);) \
default: \
BSON_UNREACHABLE ("Invalid bson_memory_order value"); \
} \
Expand All @@ -102,6 +133,12 @@ enum bson_memory_order {
false, /* Not weak */ \
GNU_MemOrder, \
GNU_MemOrder);) \
BSON_IF_GNU_LEGACY_ATOMICS ( \
__typeof__ (ExpectActualVar) _val; \
_val = __sync_val_compare_and_swap (Ptr, \
ExpectActualVar, \
NewValue); \
ExpectActualVar = _val;) \
} while (0)


Expand All @@ -118,6 +155,12 @@ enum bson_memory_order {
true, /* Yes weak */ \
GNU_MemOrder, \
GNU_MemOrder);) \
BSON_IF_GNU_LEGACY_ATOMICS ( \
__typeof__ (ExpectActualVar) _val; \
_val = __sync_val_compare_and_swap (Ptr, \
ExpectActualVar, \
NewValue); \
ExpectActualVar = _val;) \
} while (0)


Expand All @@ -127,6 +170,7 @@ enum bson_memory_order {
{ \
DEF_ATOMIC_OP (BSON_CONCAT (_InterlockedExchangeAdd, VCIntrinSuffix), \
__atomic_fetch_add, \
__sync_fetch_and_add, \
ord, \
a, \
addend); \
Expand All @@ -139,7 +183,9 @@ enum bson_memory_order {
BSON_IF_MSVC ( \
return bson_atomic_##NamePart##_fetch_add (a, -subtrahend, ord);) \
BSON_IF_GNU_LIKE ( \
DEF_ATOMIC_OP (~, __atomic_fetch_sub, ord, a, subtrahend);) \
DEF_ATOMIC_OP (~, __atomic_fetch_sub, ~, ord, a, subtrahend);) \
BSON_IF_GNU_LEGACY_ATOMICS ( \
DEF_ATOMIC_OP (~, ~, __sync_fetch_and_sub, ord, a, subtrahend);) \
} \
\
static BSON_INLINE Type bson_atomic_##NamePart##_fetch ( \
Expand All @@ -164,13 +210,15 @@ enum bson_memory_order {
default: \
BSON_UNREACHABLE ("Invalid bson_memory_order value"); \
}) \
BSON_IF_GNU_LEGACY_ATOMICS ({ __sync_synchronize (); return *a; }) \
} \
\
static BSON_INLINE Type bson_atomic_##NamePart##_exchange ( \
Type volatile *a, Type value, enum bson_memory_order ord) \
{ \
BSON_IF_MSVC ( \
DEF_ATOMIC_OP (BSON_CONCAT (_InterlockedExchange, VCIntrinSuffix), \
~, \
~, \
ord, \
a, \
Expand All @@ -192,6 +240,8 @@ enum bson_memory_order {
default: \
BSON_UNREACHABLE ("Invalid bson_memory_order value"); \
}) \
BSON_IF_GNU_LEGACY_ATOMICS ( \
return __sync_val_compare_and_swap (a, *a, value);) \
} \
\
static BSON_INLINE Type bson_atomic_##NamePart##_compare_exchange_strong ( \
Expand Down Expand Up @@ -285,7 +335,7 @@ enum bson_memory_order {
#define DECL_ATOMIC_STDINT(Name, VCSuffix) \
DECL_ATOMIC_INTEGRAL (Name, Name##_t, VCSuffix)

#ifdef _MSC_VER
#if defined(_MSC_VER) || defined (BSON_USE_LEGACY_GCC_ATOMICS)
/* MSVC expects precise types for their atomic intrinsics. */
DECL_ATOMIC_INTEGRAL (int8, char, 8);
DECL_ATOMIC_INTEGRAL (int16, short, 16)
Expand Down Expand Up @@ -388,8 +438,23 @@ bson_atomic_ptr_exchange (void *volatile *ptr,
void *new_value,
enum bson_memory_order ord)
{
DEF_ATOMIC_OP (
_InterlockedExchangePointer, __atomic_exchange_n, ord, ptr, new_value);
/* The older __sync_val_compare_and_swap also takes oldval */
#if defined(BSON_USE_LEGACY_GCC_ATOMICS)
DEF_ATOMIC_OP (_InterlockedExchangePointer,
,
__sync_val_compare_and_swap,
ord,
ptr,
*ptr,
new_value);
#else
DEF_ATOMIC_OP (_InterlockedExchangePointer,
__atomic_exchange_n,
,
ord,
ptr,
new_value);
#endif
}

static BSON_INLINE void *
Expand Down Expand Up @@ -500,8 +565,16 @@ bson_atomic_thread_fence ()
{
BSON_IF_MSVC (MemoryBarrier ();)
BSON_IF_GNU_LIKE (__sync_synchronize ();)
BSON_IF_GNU_LEGACY_ATOMICS (__sync_synchronize ();)
}

#ifdef BSON_USE_LEGACY_GCC_ATOMICS
#undef BSON_IF_GNU_LIKE
#define BSON_IF_GNU_LIKE(...) __VA_ARGS__
#endif
#undef BSON_IF_GNU_LEGACY_ATOMICS
#undef BSON_USE_LEGACY_GCC_ATOMICS

BSON_GNUC_DEPRECATED_FOR ("bson_atomic_thread_fence")
BSON_EXPORT (void) bson_memory_barrier (void);

Expand Down
67 changes: 36 additions & 31 deletions src/libbson/tests/test-atomic.c
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Expand Up @@ -22,37 +22,42 @@
#define ATOMIC(Kind, Operation) BSON_CONCAT4 (bson_atomic_, Kind, _, Operation)


#define TEST_KIND_WITH_MEMORDER(Kind, TypeName, MemOrder, Assert) \
do { \
TypeName got; \
TypeName value = 0; \
got = ATOMIC (Kind, fetch) (&value, MemOrder); \
Assert (got, ==, 0); \
got = ATOMIC (Kind, fetch_add) (&value, 42, MemOrder); \
Assert (got, ==, 0); \
Assert (value, ==, 42); \
got = ATOMIC (Kind, fetch_sub) (&value, 7, MemOrder); \
Assert (got, ==, 42); \
Assert (value, ==, 35); \
got = ATOMIC (Kind, exchange) (&value, 77, MemOrder); \
Assert (got, ==, 35); \
Assert (value, ==, 77); \
/* Compare-exchange fail: */ \
got = ATOMIC (Kind, compare_exchange_strong) (&value, 4, 9, MemOrder); \
Assert (got, ==, 77); \
Assert (value, ==, 77); \
/* Compare-exchange succeed: */ \
got = ATOMIC (Kind, compare_exchange_strong) (&value, 77, 9, MemOrder); \
Assert (got, ==, 77); \
Assert (value, ==, 9); \
/* Compare-exchange fail: */ \
got = ATOMIC (Kind, compare_exchange_weak) (&value, 8, 12, MemOrder); \
Assert (got, ==, 9); \
Assert (value, ==, 9); \
/* Compare-exchange succeed: */ \
got = ATOMIC (Kind, compare_exchange_weak) (&value, 9, 53, MemOrder); \
Assert (got, ==, 9); \
Assert (value, ==, 53); \
#define TEST_KIND_WITH_MEMORDER(Kind, TypeName, MemOrder, Assert) \
do { \
int i; \
TypeName got; \
TypeName value = 0; \
got = ATOMIC (Kind, fetch) (&value, MemOrder); \
Assert (got, ==, 0); \
got = ATOMIC (Kind, fetch_add) (&value, 42, MemOrder); \
Assert (got, ==, 0); \
Assert (value, ==, 42); \
got = ATOMIC (Kind, fetch_sub) (&value, 7, MemOrder); \
Assert (got, ==, 42); \
Assert (value, ==, 35); \
got = ATOMIC (Kind, exchange) (&value, 77, MemOrder); \
Assert (got, ==, 35); \
Assert (value, ==, 77); \
/* Compare-exchange fail: */ \
got = ATOMIC (Kind, compare_exchange_strong) (&value, 4, 9, MemOrder); \
Assert (got, ==, 77); \
Assert (value, ==, 77); \
/* Compare-exchange succeed: */ \
got = ATOMIC (Kind, compare_exchange_strong) (&value, 77, 9, MemOrder); \
Assert (got, ==, 77); \
Assert (value, ==, 9); \
/* Compare-exchange fail: */ \
got = ATOMIC (Kind, compare_exchange_weak) (&value, 8, 12, MemOrder); \
Assert (got, ==, 9); \
Assert (value, ==, 9); \
/* Compare-exchange-weak succeed: */ \
/* 'weak' may fail spuriously, so it must *eventually* succeed */ \
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Can't argue with that haha.

for (i = 0; i < 10000 && value != 53; ++i) { \
got = ATOMIC (Kind, compare_exchange_weak) (&value, 9, 53, MemOrder); \
Assert (got, ==, 9); \
} \
/* Check that it evenutally succeeded */ \
Assert (value, ==, 53); \
} while (0)

#define TEST_INTEGER_KIND(Kind, TypeName, Assert) \
Expand Down