Changeset f1fae414 in mainline for kernel/generic/src/time/delay.c

Timestamp:

2011-06-22T01:34:53Z (13 years ago)

Author:

Petr Koupy <petr.koupy@…>

Branches:

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

Children:

8d7e82c1, cac458f

Parents:

72ec8cc (diff), bf172825 (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:

• kernel/generic/src/time/delay.c (modified) (3 diffs)

kernel/generic/src/time/delay.c

@@ -37 +37 @@
  
 #include <time/delay.h>
+#include <proc/thread.h>
 #include <typedefs.h>
 #include <cpu.h>
@@ -42 +43 @@
 #include <arch.h>
 
-/** Active delay
+/** Delay the execution for the given number of microseconds (or slightly more).
  *
- * Delay the execution for the given number
- * of microseconds (or slightly more). The delay
- * is implemented as CPU calibrated active loop.
+ * The delay is implemented as active delay loop.
  *
  * @param usec Number of microseconds to sleep.
@@ -52 +51 @@
 void delay(uint32_t usec)
 {
-        ipl_t ipl;
-        
         /* 
-         * The delay loop is calibrated for each and every
-         * CPU in the system. Therefore it is necessary to
-         * call interrupts_disable() before calling the
-         * asm_delay_loop().
+         * The delay loop is calibrated for each and every CPU in the system.
+         * If running in a thread context, it is therefore necessary to disable
+         * thread migration. We want to do this in a lightweight manner.
          */
-        ipl = interrupts_disable();
+        if (THREAD)
+                thread_migration_disable();
         asm_delay_loop(usec * CPU->delay_loop_const);
-        interrupts_restore(ipl);
+        if (THREAD)
+                thread_migration_enable();
 }