procyberian/gcc
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

libatomic: Fix up libat_{,un}lock_n for mingw [PR119796]

Browse source 
Here is just a port of the previously posted patch to mingw which
clearly has the same problems.

2025-04-16  Jakub Jelinek  <jakub@redhat.com>

	PR libgcc/101075
	PR libgcc/119796
	* config/mingw/lock.c (libat_lock_n, libat_unlock_n): Start with
	computing how many locks will be needed and take into account
	((uintptr_t)ptr % WATCH_SIZE).  If some locks from the end of the
	locks array and others from the start of it will be needed, first
	lock the ones from the start followed by ones from the end.
This commit is contained in:
Jakub Jelinek 2025-04-16 17:22:49 +02:00 • committed by Jakub Jelinek
parent 61dfb0747a
commit 34fe8e9000
1 changed files with 32 additions and 18 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

50
libatomic/config/mingw/lock.c
View file

@ -87,21 +87,30 @@ libat_lock_n (void *ptr, size_t n)
{
uintptr_t h = addr_hash (ptr);
size_t i = 0;
size_t nlocks
= (n + ((uintptr_t)ptr % WATCH_SIZE) + WATCH_SIZE - 1) / WATCH_SIZE;
/* Don't lock more than all the locks we have. */
if (n > PAGE_SIZE)
n = PAGE_SIZE;
if (nlocks > NLOCKS)
nlocks = NLOCKS;
do
if (__builtin_expect (h + nlocks > NLOCKS, 0))
{
size_t j = h + nlocks - NLOCKS;
for (; i < j; ++i)
{
if (!locks[i].mutex)
locks[i].mutex = CreateMutex (NULL, FALSE, NULL);
WaitForSingleObject (locks[i].mutex, INFINITE);
}
}
for (; i < nlocks; ++i)
{
if (!locks[h].mutex)
locks[h].mutex = CreateMutex (NULL, FALSE, NULL);
WaitForSingleObject (locks[h].mutex, INFINITE);
if (++h == NLOCKS)
h = 0;
i += WATCH_SIZE;
locks[h].mutex = CreateMutex (NULL, FALSE, NULL);
WaitForSingleObject (locks[h++].mutex, INFINITE);
}
while (i < n);
}
void
@ -109,17 +118,22 @@ libat_unlock_n (void *ptr, size_t n)
{
uintptr_t h = addr_hash (ptr);
size_t i = 0;
size_t nlocks
= (n + ((uintptr_t)ptr % WATCH_SIZE) + WATCH_SIZE - 1) / WATCH_SIZE;
if (n > PAGE_SIZE)
n = PAGE_SIZE;
/* Don't lock more than all the locks we have. */
if (nlocks > NLOCKS)
nlocks = NLOCKS;
do
if (__builtin_expect (h + nlocks > NLOCKS, 0))
{
if (locks[h].mutex)
ReleaseMutex (locks[h].mutex);
if (++h == NLOCKS)
h = 0;
i += WATCH_SIZE;
size_t j = h + nlocks - NLOCKS;
for (; i < j; ++i)
if (locks[i].mutex)
ReleaseMutex (locks[i].mutex);
}
while (i < n);
for (; i < nlocks; ++i, ++h)
if (locks[h].mutex)
ReleaseMutex (locks[h].mutex);
}