Changeset 303c94c in mainline

Timestamp:

2006-03-23T21:13:37Z (19 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

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

Children:

38ee55b

Parents:

a0bb10ef

Message:

Improved futexes. (kernel part)

Location:

generic

Files:

• include/synch/futex.h (modified) (1 diff)
• src/synch/futex.c (modified) (10 diffs)

generic/include/synch/futex.h

@@ -44 +44 @@
 
 extern void futex_init(void);
-extern __native sys_futex_sleep(__address uaddr);
+extern __native sys_futex_sleep_timeout(__address uaddr, __u32 usec, int trydown);
 extern __native sys_futex_wakeup(__address uaddr);
 

generic/src/synch/futex.c

@@ -30 +30 @@
  * Kernel backend for futexes.
  * Deallocation of orphaned kernel-side futex structures is not currently implemented.
- * Timeouting futexes are currently not implemented.
  */
 
 #include <synch/futex.h>
 #include <synch/rwlock.h>
+#include <synch/spinlock.h>
 #include <synch/synch.h>
 #include <mm/frame.h>
 #include <mm/page.h>
 #include <mm/slab.h>
+#include <proc/thread.h>
 #include <genarch/mm/page_pt.h>
 #include <genarch/mm/page_ht.h>
@@ -91 +92 @@
  *
  * @param uaddr Userspace address of the futex counter.
- *
- * @return One of ESYNCH_OK_ATOMIC and ESYNCH_OK_BLOCKED. See synch.h.
+ * @param usec If non-zero, number of microseconds this thread is willing to sleep.
+ * @param trydown If usec is zero and trydown is non-zero, conditional operation will be attempted.
+ *
+ * @return One of ESYNCH_TIMEOUT, ESYNCH_OK_ATOMIC and ESYNCH_OK_BLOCKED. See synch.h.
  *         If there is no physical mapping for uaddr ENOENT is returned.
  */
-__native sys_futex_sleep(__address uaddr)
+__native sys_futex_sleep_timeout(__address uaddr, __u32 usec, int trydown)
 {
         futex_t *futex;
@@ -101 +104 @@
         link_t *item;
         pte_t *t;
-        
+        ipl_t ipl;
+        
+        ipl = interrupts_disable();
+
         /*
          * Find physical address of futex counter.
@@ -109 +115 @@
         if (!t || !PTE_VALID(t) || !PTE_PRESENT(t)) {
                 page_table_unlock(AS, true);
+                interrupts_restore(ipl);
                 return (__native) ENOENT;
         }
@@ -114 +121 @@
         page_table_unlock(AS, true);
         
+        interrupts_restore(ipl);        
+
         /*
          * Find the respective futex structure
@@ -149 +158 @@
         }
         
-        return (__native) waitq_sleep(&futex->wq);
+        return (__native) waitq_sleep_timeout(&futex->wq, usec, trydown);
 }
 
@@ -165 +174 @@
         link_t *item;
         pte_t *t;
+        ipl_t ipl;
+        
+        ipl = interrupts_disable();
         
         /*
@@ -173 +185 @@
         if (!t || !PTE_VALID(t) || !PTE_PRESENT(t)) {
                 page_table_unlock(AS, true);
+                interrupts_restore(ipl);
                 return (__native) ENOENT;
         }
@@ -178 +191 @@
         page_table_unlock(AS, true);
         
+        interrupts_restore(ipl);
+
         /*
          * Find the respective futex structure.
@@ -187 +202 @@
         }
         rwlock_read_unlock(&futex_ht_lock);
-        
+
         if (!futex)
                 return (__native) ENOENT;