Changeset 4621d23 in mainline for kernel/arch/arm32/src/atomic.c

Timestamp:

2018-09-06T19:54:11Z (7 years ago)

Author:

Jiří Zárevúcky <jiri.zarevucky@…>

Branches:

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

Children:

508b0df1

Parents:

ffa73c6

git-author:

Jiří Zárevúcky <jiri.zarevucky@…> (2018-08-13 03:00:17)

git-committer:

Jiří Zárevúcky <jiri.zarevucky@…> (2018-09-06 19:54:11)

Message:

Use compiler builtins for kernel atomics

File:

• kernel/arch/arm32/src/atomic.c (modified) (1 diff)

kernel/arch/arm32/src/atomic.c

@@ -36 +36 @@
 #include <synch/spinlock.h>
 #include <arch/barrier.h>
+#include <arch/asm.h>
 
+unsigned __atomic_fetch_add_4(volatile unsigned *mem, unsigned val, int model)
+{
+        /*
+         * This implementation is for UP pre-ARMv6 systems where we do not have
+         * the LDREX and STREX instructions.
+         */
+        ipl_t ipl = interrupts_disable();
+        unsigned ret = *mem;
+        *mem += val;
+        interrupts_restore(ipl);
+        return ret;
+}
+
+unsigned __atomic_fetch_sub_4(volatile unsigned *mem, unsigned val, int model)
+{
+        ipl_t ipl = interrupts_disable();
+        unsigned ret = *mem;
+        *mem -= val;
+        interrupts_restore(ipl);
+        return ret;
+}
 
 IRQ_SPINLOCK_STATIC_INITIALIZE_NAME(cas_lock, "arm-cas-lock");