yuqei/jemalloc
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Use relaxed atomics to access the process madvise pid fd

Browse Source 
Relaxed atomics already provide sequentially consistent access to single
location data structures.
This commit is contained in:
lexprfuncall
2025-08-04 13:13:27 -07:00
parent 16c5abd1cd
commit c45b6223e5
1 changed files with 5 additions and 5 deletions
Download Patch File Download Diff File Expand all files Collapse all files
src/pages.c
+5 -5
View File
@@ -646,7 +646,7 @@ init_process_madvise(void) {
static bool
pages_purge_process_madvise_impl(
void *vec, size_t vec_len, size_t total_bytes) {
int pid_fd = atomic_load_i(&process_madvise_pidfd, ATOMIC_SEQ_CST);
int pid_fd = atomic_load_i(&process_madvise_pidfd, ATOMIC_RELAXED);
while (pid_fd == -1) {
int newfd = syscall(SYS_pidfd_open, getpid(), 0);
if (newfd == -1) {
@@ -654,8 +654,8 @@ pages_purge_process_madvise_impl(
}
if (!atomic_compare_exchange_strong_i(&process_madvise_pidfd,
&pid_fd, newfd,
ATOMIC_SEQ_CST,
ATOMIC_SEQ_CST)) {
ATOMIC_RELAXED,
ATOMIC_RELAXED)) {
/* Someone else set the fd, so we close ours */
assert(pid_fd != -1);
close(newfd);
@@ -671,9 +671,9 @@ pages_purge_process_madvise_impl(
void pages_postfork_child(void) {
/* Reset the file descriptor we inherited from parent process */
int pid_fd = atomic_load_i(&process_madvise_pidfd, ATOMIC_SEQ_CST);
int pid_fd = atomic_load_i(&process_madvise_pidfd, ATOMIC_RELAXED);
if (pid_fd != -1) {
atomic_store_i(&process_madvise_pidfd, -1, ATOMIC_SEQ_CST);
atomic_store_i(&process_madvise_pidfd, -1, ATOMIC_RELAXED);
close(pid_fd);
}
}