Commit 0f3111379b940823090b3a0e540aa04fac64dc5b | zig

author	Andrew Kelley <andrew@ziglang.org> 2020-09-24 00:01:22-04:00
committer	GitHub <noreply@github.com> 2020-09-24 00:01:22-04:00
log	0f3111379b940823090b3a0e540aa04fac64dc5b
tree	03ab9dd96f9d8d334bb8902a5e2a6387af321aae
parent	274c55b780c8ef954f335536bdfcf79cd8d9f6ca
parent	bbff6bd6754bbddef03e163406d09c748a479073
signature	Signed by PGP key 4AEE18F83AFDEB23

Eventloop: Fix deadlock in linux event loop implementation

1 files changed, 8 insertions(+), 8 deletions(-)

lib/std/event/loop.zig+8-8

 @@ -687,9 +687,14 @@ pub const Loop = struct {
             switch (builtin.os.tag) {
                 .linux => {
-                    // writing 8 bytes to an eventfd cannot fail
+                    // writing to the eventfd will only wake up one thread, thus multiple writes
-                    const amt = os.write(self.os_data.final_eventfd, &wakeup_bytes) catch unreachable;
+                    // are needed to wakeup all the threads
-                    assert(amt == wakeup_bytes.len);
+                    var i: usize = 0;
+                    while (i < self.extra_threads.len + 1) : (i += 1) {
+                        // writing 8 bytes to an eventfd cannot fail
+                        const amt = os.write(self.os_data.final_eventfd, &wakeup_bytes) catch unreachable;
+                        assert(amt == wakeup_bytes.len);
+                    }
                     return;
                 },
                 .macosx, .freebsd, .netbsd, .dragonfly => {
 @@ -1252,11 +1257,6 @@ test "std.event.Loop - basic" {
     // https://github.com/ziglang/zig/issues/1908
     if (builtin.single_threaded) return error.SkipZigTest;
-    if (true) {
-        // https://github.com/ziglang/zig/issues/4922
-        return error.SkipZigTest;
-    }
     var loop: Loop = undefined;
     try loop.initMultiThreaded();
     defer loop.deinit();