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Implement cpu_thread::suspend_all
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Remove Accurate PUTLLC option.
Implement fallback path for SPU transactions.
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Nekotekina committed Jun 7, 2019
1 parent 1dedeb3 commit f660ef0
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Showing 11 changed files with 638 additions and 127 deletions.
153 changes: 153 additions & 0 deletions Utilities/cond.cpp
Expand Up @@ -273,6 +273,159 @@ void shared_cond::imp_notify() noexcept
balanced_awaken<true>(m_cvx32, utils::popcnt32(wait_mask));
}

void shared_cond::wait_all() noexcept
{
// Try to acquire waiting state without locking but only if there are other locks
const auto [old_, result] = m_cvx32.fetch_op([](u64& cvx32) -> u64
{
// Check waiting alone
if ((cvx32 & 0xffffffff) == 0)
{
return 0;
}

// Combine used bits and invert to find least significant bit unused
const u32 slot = utils::cnttz64(~((cvx32 & 0xffffffff) | (cvx32 >> 32)), true);

// Set waiting bit (does nothing if all slots are used)
cvx32 |= (1ull << slot) & 0xffffffff;
return 1ull << slot;
});

if (!result)
{
return;
}

if (result > 0xffffffffu)
{
// All slots are used, fallback to spin wait
while (m_cvx32 & 0xffffffff)
{
busy_wait();
}

return;
}

const u64 wait_bit = result;
const u64 lock_bit = wait_bit | (wait_bit << 32);

balanced_wait_until(m_cvx32, -1, [&](u64& cvx32, auto... ret) -> int
{
if ((cvx32 & wait_bit) == 0)
{
// Remove signal and unlock at once
cvx32 &= ~lock_bit;
return +1;
}

if constexpr (sizeof...(ret))
{
cvx32 &= ~lock_bit;
return -1;
}

return 0;
});
}

bool shared_cond::wait_all(shared_cond::shared_lock& lock) noexcept
{
AUDIT(lock.m_this == this);

if (lock.m_slot >= 32)
{
// Invalid argument, assume notified
return true;
}

const u64 wait_bit = c_wait << lock.m_slot;
const u64 lock_bit = c_lock << lock.m_slot;

// Try to acquire waiting state only if there are other locks
const auto [old_, not_alone] = m_cvx32.fetch_op([&](u64& cvx32)
{
// Check locking alone
if (((cvx32 >> 32) & cvx32) == (lock_bit >> 32))
{
return false;
}

// c_lock -> c_wait, c_sig -> unlock
cvx32 &= ~(lock_bit & ~wait_bit);
return true;
});

if (!not_alone)
{
return false;
}
else
{
// Set invalid slot to acknowledge unlocking
lock.m_slot = 33;
}

if ((old_ & wait_bit) == 0)
{
// Already signaled, return without waiting
return true;
}

balanced_wait_until(m_cvx32, -1, [&](u64& cvx32, auto... ret) -> int
{
if ((cvx32 & wait_bit) == 0)
{
// Remove signal and unlock at once
cvx32 &= ~lock_bit;
return +1;
}

if constexpr (sizeof...(ret))
{
cvx32 &= ~lock_bit;
return -1;
}

return 0;
});

return true;
}

void shared_cond::notify_all(shared_cond::shared_lock& lock) noexcept
{
AUDIT(lock.m_this == this);

const u64 slot_mask = c_sig << lock.m_slot;

auto [old, ok] = m_cvx32.fetch_op([&](u64& cvx32)
{
if (const u64 sig_mask = cvx32 & 0xffffffff)
{
cvx32 &= (0xffffffffull << 32) & ~slot_mask;
cvx32 |= (sig_mask << 32) & ~slot_mask;
return true;
}

return false;
});

// Set invalid slot to acknowledge unlocking
lock.m_slot = 34;

// Determine if some waiters need a syscall notification
const u64 wait_mask = old & (~old >> 32);

if (UNLIKELY(!ok || !wait_mask))
{
return;
}

balanced_awaken<true>(m_cvx32, utils::popcnt32(wait_mask));
}

bool lf_queue_base::wait(u64 _timeout)
{
auto _old = m_head.compare_and_swap(0, 1);
Expand Down
15 changes: 14 additions & 1 deletion Utilities/cond.h
Expand Up @@ -206,7 +206,7 @@ class shared_cond
m_slot = m_this->m_cvx32.atomic_op([](u64& cvx32)
{
// Combine used bits and invert to find least significant bit unused
const u32 slot = utils::cnttz32(~((cvx32 & 0xffffffff) | (cvx32 >> 32)), true);
const u32 slot = utils::cnttz64(~((cvx32 & 0xffffffff) | (cvx32 >> 32)), true);

// Set lock bits (does nothing if all slots are used)
const u64 bit = (1ull << slot) & 0xffffffff;
Expand All @@ -217,6 +217,13 @@ class shared_cond

shared_lock(const shared_lock&) = delete;

shared_lock(shared_lock&& rhs)
: m_this(rhs.m_this)
, m_slot(rhs.m_slot)
{
rhs.m_slot = 32;
}

shared_lock& operator=(const shared_lock&) = delete;

~shared_lock()
Expand Down Expand Up @@ -261,11 +268,17 @@ class shared_cond
return imp_wait(lock.m_slot, usec_timeout);
}

void wait_all() noexcept;

bool wait_all(shared_lock& lock) noexcept;

void notify_all() noexcept
{
if (LIKELY(!m_cvx32))
return;

imp_notify();
}

void notify_all(shared_lock& lock) noexcept;
};

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