Changeset d30e067 in mainline for uspace/lib/c/generic/thread/fibril_synch.c

Timestamp:

2025-03-02T20:02:33Z (5 months ago)

Author:

Miroslav Cimerman <mc@…>

Children:

8cdf360

Parents:

7debda3 (diff), 4285f384 (diff)
Note: this is a merge changeset, the changes displayed below correspond to the merge itself.
Use the (diff) links above to see all the changes relative to each parent.

Message:

Merge 'upstream/master' into helenraid-para

File:

• uspace/lib/c/generic/thread/fibril_synch.c (modified) (5 diffs)

uspace/lib/c/generic/thread/fibril_synch.c

@@ -1 +1 @@
 /*
+ * Copyright (c) 2025 Jiri Svoboda
  * Copyright (c) 2009 Jakub Jermar
  * All rights reserved.
@@ -112 +113 @@
 #define AWAITER_INIT { .fid = fibril_get_id() }
 
-static void print_deadlock(fibril_owner_info_t *oi)
+/** Print deadlock message nad blocking chain.
+ *
+ * @param oi Owner info for the resource being acquired
+ * @param f Fibril that is trying to acquire the resource
+ */
+static void print_deadlock(fibril_owner_info_t *oi, fibril_t *f)
 {
         // FIXME: Print to stderr.
-
-        fibril_t *f = (fibril_t *) fibril_get_id();
 
         if (deadlocked) {
@@ -143 +147 @@
 }
 
-static void check_fibril_for_deadlock(fibril_owner_info_t *oi, fibril_t *fib)
-{
+/** Check whether fibril trying to acquire a resource will cause deadlock.
+ *
+ * @param wanted_oi Owner info for the primitive that the fibril wants
+ * @param fib Fibril that wants to aquire the primitive
+ */
+static void check_fibril_for_deadlock(fibril_owner_info_t *wanted_oi,
+    fibril_t *fib)
+{
+        fibril_owner_info_t *oi;
+
         futex_assert_is_locked(&fibril_synch_futex);
 
+        oi = wanted_oi;
         while (oi && oi->owned_by) {
                 if (oi->owned_by == fib) {
                         futex_unlock(&fibril_synch_futex);
-                        print_deadlock(oi);
+                        print_deadlock(wanted_oi, fib);
                         abort();
                 }
@@ -157 +170 @@
 }
 
+/** Check whether trying to acquire a resource will cause deadlock.
+ *
+ * @param oi Owner info for the primitive that the current fibril wants
+ */
 static void check_for_deadlock(fibril_owner_info_t *oi)
 {
@@ -246 +263 @@
         futex_lock(&fibril_synch_futex);
 
-        if (!frw->writers) {
+        if (!frw->writers && list_empty(&frw->waiters)) {
                 /* Consider the first reader the owner. */
                 if (frw->readers++ == 0)