Changeset 4687a26c in mainline for uspace/lib/c/generic/fibril_synch.c

Timestamp:

2010-11-02T18:29:01Z (13 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

4f35b9ff

Parents:

76e1121f (diff), 28f4adb (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 mainline changes.

File:

• uspace/lib/c/generic/fibril_synch.c (modified) (8 diffs)

uspace/lib/c/generic/fibril_synch.c

@@ -42 +42 @@
 #include <errno.h>
 #include <assert.h>
+#include <stacktrace.h>
+#include <stdlib.h>
 
 static void optimize_execution_power(void)
@@ -56 +58 @@
 }
 
+static bool check_for_deadlock(fibril_owner_info_t *oi)
+{
+        while (oi && oi->owned_by) {
+                if (oi->owned_by == (fibril_t *) fibril_get_id())
+                        return true;
+                oi = oi->owned_by->waits_for;
+        }
+
+        return false;
+}
+
+static void print_deadlock(fibril_owner_info_t *oi)
+{
+        fibril_t *f = (fibril_t *) fibril_get_id();
+
+        printf("Deadlock detected.\n");
+        stacktrace_print();
+
+        printf("Fibril %p waits for primitive %p.\n", f, oi);
+
+        while (oi && oi->owned_by) {
+                printf("Primitive %p is owned by fibril %p.\n",
+                    oi, oi->owned_by);
+                if (oi->owned_by == f)
+                        break;
+                stacktrace_print_fp_pc(context_get_fp(&oi->owned_by->ctx),
+                    oi->owned_by->ctx.pc);
+                printf("Fibril %p waits for primitive %p.\n",
+                     oi->owned_by, oi->owned_by->waits_for);
+                oi = oi->owned_by->waits_for;
+        }
+
+        abort();
+}
+
 void fibril_mutex_initialize(fibril_mutex_t *fm)
 {
+        fm->oi.owned_by = NULL;
         fm->counter = 1;
         list_initialize(&fm->waiters);
@@ -64 +102 @@
 void fibril_mutex_lock(fibril_mutex_t *fm)
 {
+        fibril_t *f = (fibril_t *) fibril_get_id();
+
         futex_down(&async_futex);
         if (fm->counter-- <= 0) {
@@ -73 +113 @@
                 link_initialize(&wdata.wu_event.link);
                 list_append(&wdata.wu_event.link, &fm->waiters);
+
+                if (check_for_deadlock(&fm->oi))
+                        print_deadlock(&fm->oi);
+                f->waits_for = &fm->oi;
+
                 fibril_switch(FIBRIL_TO_MANAGER);
         } else {
+                fm->oi.owned_by = f;
                 futex_up(&async_futex);
         }
@@ -86 +132 @@
         if (fm->counter > 0) {
                 fm->counter--;
+                fm->oi.owned_by = (fibril_t *) fibril_get_id();
                 locked = true;
         }
@@ -99 +146 @@
                 link_t *tmp;
                 awaiter_t *wdp;
+                fibril_t *f;
         
                 assert(!list_empty(&fm->waiters));
@@ -105 +153 @@
                 wdp->active = true;
                 wdp->wu_event.inlist = false;
+
+                f = (fibril_t *) wdp->fid;
+                fm->oi.owned_by = f;
+                f->waits_for = NULL;
+
                 list_remove(&wdp->wu_event.link);
                 fibril_add_ready(wdp->fid);
                 optimize_execution_power();
+        } else {
+                fm->oi.owned_by = NULL;
         }
 }
@@ -120 +175 @@
 void fibril_rwlock_initialize(fibril_rwlock_t *frw)
 {
+        frw->oi.owned_by = NULL;
         frw->writers = 0;
         frw->readers = 0;