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[#162] Fix 64bit atomic api issues for 32bit system #431

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[#162] Fix 64bit atomic api issues for 32bit system #431

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27 changes: 16 additions & 11 deletions elements/test/atomic.cc
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Original file line number Diff line number Diff line change
Expand Up @@ -86,29 +86,34 @@ static void test_64(ErrorHandler *)

atomic_uint64_t a;
a = 0;
click_chatter("[01] a=%i -> %s", a, a==0 ? "PASS" : "FAIL");
uint64_t u;
u = a;
click_chatter("[01] u=%llu -> %s", u, u==0 ? "PASS" : "FAIL");
a++;
click_chatter("[02] a=%i -> %s", a, a==1 ? "PASS" : "FAIL");
u=a;
click_chatter("[02] u=%llu -> %s", u, u==1 ? "PASS" : "FAIL");
a+=1;
click_chatter("[03] a=%i -> %s", a, a==2 ? "PASS" : "FAIL");
a-=1;
click_chatter("[04] a=%i -> %s", a, a==1 ? "PASS" : "FAIL");
uint32_t u = a.fetch_and_add(10);
click_chatter("[05] a=%i, u=%i -> %s", a, u, a==11 && u==1 ? "PASS" : "FAIL");
u=a;
click_chatter("[03] u=%llu -> %s", u, u==2 ? "PASS" : "FAIL");
a-=1; u=a;
click_chatter("[04] u=%llu -> %s", u, u==1 ? "PASS" : "FAIL");

u = a.fetch_and_add(10);
click_chatter("[05] a=%llu, u=%llu -> %s", (uint64_t)a, u, (uint64_t)a==11 && u==1 ? "PASS" : "FAIL");

#if CLICK_ATOMIC_BUILTINS
click_chatter("[--] Not testing compare_swap!");
#else
u = a.compare_swap(0,2);
click_chatter("[06] a=%i, u=%i -> %s", a, u, a==11 && u==11 ? "PASS" : "FAIL");
click_chatter("[06] a=%llu, u=%llu -> %s", (uint64_t)a, u, (uint64_t)a==11 && u==11 ? "PASS" : "FAIL");
u = a.compare_swap(11,5);
click_chatter("[07] a=%i, u=%i -> %s", a, u, a==5 && u==11 ? "PASS" : "FAIL");
click_chatter("[07] a=%llu, u=%llu -> %s", (uint64_t)a, u, (uint64_t)a==5 && u==11 ? "PASS" : "FAIL");
uint64_t b =5;

u = atomic_uint64_t::compare_swap(b,0,2);
click_chatter("[08] b=%i, u=%i -> %s", b, u, b==5 && u==5 ? "PASS" : "FAIL");
click_chatter("[08] b=%llu, u=%llu -> %s", b, u, b==5 && u==5 ? "PASS" : "FAIL");
u = atomic_uint64_t::compare_swap(b,5,2);
click_chatter("[09] b=%i, u=%i -> %s", b, u, b==2 && u==5 ? "PASS" : "FAIL");
click_chatter("[09] b=%llu, u=%llu -> %s", b, u, b==2 && u==5 ? "PASS" : "FAIL");
#endif
}

Expand Down
264 changes: 227 additions & 37 deletions include/click/atomic.hh
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Original file line number Diff line number Diff line change
Expand Up @@ -811,15 +811,32 @@ operator<=(const atomic_uint32_t &a, const atomic_uint32_t &b)
typedef atomic_uint32_t uatomic32_t;

//Atomic 64

/** @brief Return the value. */
inline uint64_t
atomic_uint64_t::value() const
{
#if CLICK_LINUXMODULE
return atomic64_read(&_val);
#else
return CLICK_ATOMIC_VAL;
#if defined(__x86_64__)
return CLICK_ATOMIC_VAL;
#else
uint32_t low, high;

asm volatile(
"1:\n\t"
"movl (%[addr]), %%eax\n\t" // EAX = low
"movl 4(%[addr]), %%edx\n\t" // EDX = high
"movl %%eax, %%ebx\n\t" // EDX = high
"movl %%edx, %%ecx\n\t" // EDX = high
CLICK_ATOMIC_LOCK "cmpxchg8b (%[addr])\n\t" // Compare with same value to validate consistency
"jnz 1b\n\t" // Retry if value changed during read
: "=&a" (low), "=&d" (high)
: [addr] "r" (&_val)
: "ebx", "ecx", "memory"
);
return ((uint64_t)high << 32) | low;
#endif
#endif
}

Expand All @@ -844,7 +861,23 @@ atomic_uint64_t::operator=(uint64_t x)
#if CLICK_LINUXMODULE
atomic64_set(&_val, x);
#else
CLICK_ATOMIC_VAL = x;
#if defined(__x86_64__)
CLICK_ATOMIC_VAL = x;
#else
uint32_t nlow = static_cast<uint32_t>(x & 0xFFFFFFFF);
uint32_t nhigh = static_cast<uint32_t>(x >> 32);
asm volatile (
"1:\n\t"
"movl (%[addr]), %%eax\n\t" // EAX = old low
"movl 4(%[addr]), %%edx\n\t" // EDX = old high
CLICK_ATOMIC_LOCK "cmpxchg8b (%[addr])\n\t" // Atomically write ECX:EBX if EDX:EAX match
"jnz 1b\n\t" // Retry if compare failed
:
: [addr] "r" (&_val),
"b" (nlow),"c"(nhigh)
: "eax", "edx", "memory"
);
#endif
#endif
return *this;
}
Expand All @@ -858,10 +891,34 @@ atomic_uint64_t::operator+=(int64_t delta)
#elif CLICK_ATOMIC_BUILTINS
__atomic_add_fetch(&_val, delta, CLICK_ATOMIC_MEMORDER);
#elif CLICK_ATOMIC_X86
asm volatile (CLICK_ATOMIC_LOCK "addq %1,%0"
#if defined(__x86_64__)
asm volatile (CLICK_ATOMIC_LOCK "addq %1,%0"
: "=m" (CLICK_ATOMIC_VAL)
: "r" (delta), "m" (CLICK_ATOMIC_VAL)
: "cc");
#else
uint32_t dlow = static_cast<uint32_t>(delta & 0xFFFFFFFF);
int32_t dhigh = static_cast<int32_t>(delta >> 32);

asm volatile (
"movl %%ebx, %%esi\n\t" // Save EBX (needed for PIC)
"1:\n\t"
"movl (%[addr]), %%eax\n\t" // EAX = old low
"movl 4(%[addr]), %%edx\n\t" // EDX = old high
"movl %%eax, %%ebx\n\t" // EBX = expected low
"movl %%edx, %%ecx\n\t" // ECX = expected high
"addl %[delta_low], %%ebx\n\t" // EBX = new low
"adcl %[delta_high], %%ecx\n\t" // ECX = new high (+ carry)
CLICK_ATOMIC_LOCK "cmpxchg8b (%[addr])\n\t" // Atomically compare and exchange
"jnz 1b\n\t" // Retry if comparison failed
"movl %%esi, %%ebx\n\t" // Restore EBX
:
: [addr] "r" (&_val),
[delta_low] "m" (dlow),
[delta_high] "m" (dhigh) // sign-extend high part
: "eax", "edx", "ecx", "esi", "memory"
);
#endif
#else
CLICK_ATOMIC_VAL += delta;
#endif
Expand All @@ -877,10 +934,32 @@ atomic_uint64_t::add(volatile uint64_t &x, uint64_t delta)
#elif CLICK_ATOMIC_BUILTINS
__atomic_add_fetch(&x, delta, CLICK_ATOMIC_MEMORDER);
#elif CLICK_ATOMIC_X86
asm volatile (CLICK_ATOMIC_LOCK "addq %1,%0"
: "=m" (x)
: "r" (delta), "m" (x)
: "cc");
#if defined(__x86_64__)
asm volatile (CLICK_ATOMIC_LOCK "addq %1,%0"
: "=m" (x)
: "r" (delta), "m" (x)
: "cc");
#else
uint32_t dlow = static_cast<uint32_t>(delta & 0xFFFFFFFF);
uint32_t dhigh = static_cast<uint32_t>(delta >> 32);
asm volatile (
"movl %%ebx, %%esi\n\t" // Save EBX
"1:\n\t"
"movl (%[addr]), %%eax\n\t" // EAX = old low
"movl 4(%[addr]), %%edx\n\t" // EDX = old high
"movl %%eax, %%ebx\n\t" // EBX = expected low
"movl %%edx, %%ecx\n\t" // ECX = expected high
"addl %[delta_low], %%ebx\n\t" // EBX = new low
"adcl %[delta_high], %%ecx\n\t" // ECX = new high (+ carry)
CLICK_ATOMIC_LOCK "cmpxchg8b (%[addr])\n\t" // Try to atomically swap
"jnz 1b\n\t" // Retry if failed
"movl %%esi, %%ebx\n\t" // Restore EBX
:
: [addr] "r" (&x),
[delta_low] "m" (dlow),
[delta_high] "m" (dhigh)
: "eax", "edx", "ecx", "esi", "memory");
#endif
#else
x += delta;
#endif
Expand All @@ -895,10 +974,29 @@ atomic_uint64_t::operator-=(int64_t delta)
#elif CLICK_ATOMIC_BUILTINS
__atomic_sub_fetch(&CLICK_ATOMIC_VAL, delta, CLICK_ATOMIC_MEMORDER);
#elif CLICK_ATOMIC_X86
asm volatile (CLICK_ATOMIC_LOCK "subq %1,%0"
: "=m" (CLICK_ATOMIC_VAL)
: "r" (delta), "m" (CLICK_ATOMIC_VAL)
: "cc");
#if defined(__x86_64__)
asm volatile (CLICK_ATOMIC_LOCK "subq %1,%0"
: "=m" (CLICK_ATOMIC_VAL)
: "r" (delta), "m" (CLICK_ATOMIC_VAL)
: "cc");
#else
uint32_t dlow = static_cast<uint32_t>(delta & 0xFFFFFFFF);
int32_t dhigh = static_cast<int32_t>(delta >> 32);
asm volatile("1:\n\t"
"movl (%[addr]), %%eax\n\t" // EAX = old low
"movl 4(%[addr]), %%edx\n\t" // EDX = old high
"movl %%eax, %%ebx\n\t" // EBX = old low
"movl %%edx, %%ecx\n\t" // ECX = old high
"subl %[vlo], %%ebx\n\t" // EBX -= value low
"sbbl %[vhi], %%ecx\n\t" // ECX -= value high + borrow
CLICK_ATOMIC_LOCK "cmpxchg8b (%[addr])\n\t" // Attempt atomic CAS
"jnz 1b\n\t" // Retry if it failed
:
: [addr] "r" (&_val),
[vlo] "m" (dlow),
[vhi] "m" (dhigh)
: "eax", "ebx", "ecx", "edx", "memory");
#endif
#else
CLICK_ATOMIC_VAL -= delta;
#endif
Expand All @@ -920,10 +1018,26 @@ atomic_uint64_t::operator++()
#if CLICK_LINUXMODULE
atomic64_inc(&_val);
#elif CLICK_ATOMIC_X86
asm volatile (CLICK_ATOMIC_LOCK "incq %0"
: "=m" (CLICK_ATOMIC_VAL)
: "m" (CLICK_ATOMIC_VAL)
: "cc");
#if defined(__x86_64__)
asm volatile (CLICK_ATOMIC_LOCK "incq %0"
: "=m" (CLICK_ATOMIC_VAL)
: "m" (CLICK_ATOMIC_VAL)
: "cc");
#else
asm volatile(
"1:\n\t"
"movl (%[addr]), %%eax\n\t" // Load old low 32 bits
"movl 4(%[addr]), %%edx\n\t" // Load old high 32 bits
"movl %%eax, %%ebx\n\t" // EBX = copy of low
"movl %%edx, %%ecx\n\t" // ECX = copy of high
"addl $1, %%ebx\n\t" // Increment low
"adcl $0, %%ecx\n\t" // Add carry to high
CLICK_ATOMIC_LOCK "cmpxchg8b (%[addr])\n\t" // Attempt atomic swap
"jnz 1b\n\t" // Retry if failed
:
: [addr] "r" (&_val)
: "eax", "ebx", "ecx", "edx", "memory");
#endif
#else
CLICK_ATOMIC_VAL++;
#endif
Expand All @@ -938,10 +1052,26 @@ atomic_uint64_t::operator++(int)
#elif CLICK_ATOMIC_BUILTINS
__atomic_add_fetch(&CLICK_ATOMIC_VAL, 1, CLICK_ATOMIC_MEMORDER);
#elif CLICK_ATOMIC_X86
asm volatile (CLICK_ATOMIC_LOCK "incq %0"
: "=m" (CLICK_ATOMIC_VAL)
: "m" (CLICK_ATOMIC_VAL)
: "cc");
#if defined(__x86_64)
asm volatile (CLICK_ATOMIC_LOCK "incq %0"
: "=m" (CLICK_ATOMIC_VAL)
: "m" (CLICK_ATOMIC_VAL)
: "cc");
#else
asm volatile(
"1:\n\t"
"movl (%[addr]), %%eax\n\t"
"movl 4(%[addr]), %%edx\n\t"
"movl %%eax, %%ebx\n\t"
"movl %%edx, %%ecx\n\t"
"addl $1, %%ebx\n\t"
"adcl $0, %%ecx\n\t"
CLICK_ATOMIC_LOCK "cmpxchg8b (%[addr])\n\t"
"jnz 1b\n\t"
:
: [addr] "r" (&_val)
: "eax", "ebx", "ecx", "edx", "memory");
#endif
#else
CLICK_ATOMIC_VAL++;
#endif
Expand All @@ -956,10 +1086,26 @@ atomic_uint64_t::operator--()
#elif CLICK_ATOMIC_BUILTINS
__atomic_sub_fetch(&CLICK_ATOMIC_VAL, 1, CLICK_ATOMIC_MEMORDER);
#elif CLICK_ATOMIC_X86
asm volatile (CLICK_ATOMIC_LOCK "decq %0"
: "=m" (CLICK_ATOMIC_VAL)
: "m" (CLICK_ATOMIC_VAL)
: "cc");
#if defined(__x86_64__)
asm volatile (CLICK_ATOMIC_LOCK "decq %0"
: "=m" (CLICK_ATOMIC_VAL)
: "m" (CLICK_ATOMIC_VAL)
: "cc");
#else
asm volatile(
"1:\n\t"
"movl (%[addr]), %%eax\n\t" // Load old low
"movl 4(%[addr]), %%edx\n\t" // Load old high
"movl %%eax, %%ebx\n\t" // Copy low to EBX
"movl %%edx, %%ecx\n\t" // Copy high to ECX
"subl $1, %%ebx\n\t" // EBX -= 1 (low part)
"sbbl $0, %%ecx\n\t" // ECX -= borrow (high part)
"lock cmpxchg8b (%[addr])\n\t" // Atomic compare & swap
"jnz 1b\n\t" // Retry on failure
:
: [addr] "r" (&_val)
: "eax", "ebx", "ecx", "edx", "memory");
#endif
#else
CLICK_ATOMIC_VAL--;
#endif
Expand All @@ -981,10 +1127,26 @@ atomic_uint64_t::operator--(int)
#elif CLICK_ATOMIC_BUILTINS
__atomic_sub_fetch(&CLICK_ATOMIC_VAL, 1, CLICK_ATOMIC_MEMORDER);
#elif CLICK_ATOMIC_X86
asm volatile (CLICK_ATOMIC_LOCK "decq %0"
: "=m" (CLICK_ATOMIC_VAL)
: "m" (CLICK_ATOMIC_VAL)
: "cc");
#if defined(__x86_64__)
asm volatile (CLICK_ATOMIC_LOCK "decq %0"
: "=m" (CLICK_ATOMIC_VAL)
: "m" (CLICK_ATOMIC_VAL)
: "cc");
#else
asm volatile(
"1:\n\t"
"movl (%[addr]), %%eax\n\t" // Load old low
"movl 4(%[addr]), %%edx\n\t" // Load old high
"movl %%eax, %%ebx\n\t" // Copy low to EBX
"movl %%edx, %%ecx\n\t" // Copy high to ECX
"subl $1, %%ebx\n\t" // EBX -= 1 (low part)
"sbbl $0, %%ecx\n\t" // ECX -= borrow (high part)
CLICK_ATOMIC_LOCK "cmpxchg8b (%[addr])\n\t" // Atomic compare & swap
"jnz 1b\n\t" // Retry on failure
:
: [addr] "r" (&_val)
: "eax", "ebx", "ecx", "edx", "memory");
#endif
#else
CLICK_ATOMIC_VAL--;
#endif
Expand Down Expand Up @@ -1015,10 +1177,18 @@ atomic_uint64_t::compare_swap(volatile uint64_t &x, uint64_t expected, uint64_t
return __atomic_compare_exchange(&x,&expected,&desired,0,CLICK_ATOMIC_MEMORDER, CLICK_ATOMIC_MEMORDER)
? expected : x;
#elif CLICK_ATOMIC_X86
asm volatile (CLICK_ATOMIC_LOCK "cmpxchgq %2,%1"
: "=a" (expected), "=m" (x)
: "r" (desired), "0" (expected), "m" (x)
: "cc", "memory");
#if defined(__x86_64__)
asm volatile (CLICK_ATOMIC_LOCK "cmpxchgq %2,%1"
: "=a" (expected), "=m" (x)
: "r" (desired), "0" (expected), "m" (x)
: "cc", "memory");
#else
asm volatile (CLICK_ATOMIC_LOCK "cmpxchg8b %1\n\t" // Compare EDX:EAX with [mem], replace with ECX:EBX if equal
: "+A" (expected) //load expected into EAX:EDX
: "m" (x), // preload memory value to compare.
"b" ((uint32_t)desired), "c"((uint32_t) (desired>>32))
: "memory");
#endif
return expected;
#elif CLICK_LINUXMODULE && defined(cmpxchg)
return cmpxchg(&x, expected, desired);
Expand Down Expand Up @@ -1063,11 +1233,31 @@ atomic_uint64_t::fetch_and_add(uint64_t delta)
#if CLICK_ATOMIC_BUILTINS
return __atomic_fetch_add(&_val, delta, CLICK_ATOMIC_MEMORDER);
#elif CLICK_ATOMIC_X86
asm volatile (CLICK_ATOMIC_LOCK "xaddq %0,%1"
: "=r" (delta), "=m" (CLICK_ATOMIC_VAL)
: "0" (delta), "m" (CLICK_ATOMIC_VAL)
: "cc");
return delta;
#if defined(__x86_64__)
asm volatile (CLICK_ATOMIC_LOCK "xaddq %0,%1"
: "=r" (delta), "=m" (CLICK_ATOMIC_VAL)
: "0" (delta), "m" (CLICK_ATOMIC_VAL)
: "cc");
return delta;
#else
uint32_t old_lo=0, old_hi=0;
asm volatile (
"1:\n\t"
"movl (%2), %%eax\n\t" // Load old low 32 bits
"movl 4(%2), %%edx\n\t" // Load old high 32 bits
"movl %%eax, %%ebx\n\t" // Copy low to ebx (new low)
"movl %%edx, %%ecx\n\t" // Copy high to ecx (new high)
"addl %3, %%ebx\n\t" // new low += delta low
"adcl %4, %%ecx\n\t" // new high += delta high + carry
CLICK_ATOMIC_LOCK "cmpxchg8b (%2)\n\t" // atomic cmpxchg8b
"jnz 1b\n\t" // if fail, retry
"movl %%eax, %0\n\t" // store old low
"movl %%edx, %1\n\t" // store old high
: "=&a" (old_lo), "=&d" (old_hi)
: "r" (&_val), "r" ((uint32_t)delta), "r" ((uint32_t)(delta >> 32))
: "ebx", "ecx", "cc","memory");
return (static_cast<uint64_t>(old_hi) << 32) | old_lo;
#endif
#elif CLICK_LINUXMODULE && HAVE_LINUX_ATOMIC_ADD_RETURN
return atomic64_add_return(&_val, delta) - delta;
#elif CLICK_LINUXMODULE
Expand Down