s390: add support for transactional memory
Allow user-space processes to use transactional execution (TX).
If the TX facility is available user space programs can use
transactions for fine-grained serialization based on the data
objects that are referenced during a transaction. This is
useful for lockless data structures and speculative compiler
optimizations.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/kernel/entry64.S b/arch/s390/kernel/entry64.S
index 349b7ee..95e9d93 100644
--- a/arch/s390/kernel/entry64.S
+++ b/arch/s390/kernel/entry64.S
@@ -412,6 +412,11 @@
1: UPDATE_VTIME %r14,__LC_SYNC_ENTER_TIMER
LAST_BREAK %r14
lg %r15,__LC_KERNEL_STACK
+ lg %r14,__TI_task(%r12)
+ lghi %r13,__LC_PGM_TDB
+ tm __LC_PGM_ILC+2,0x02 # check for transaction abort
+ jz 2f
+ mvc __THREAD_trap_tdb(256,%r14),0(%r13)
2: aghi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
la %r11,STACK_FRAME_OVERHEAD(%r15)
stmg %r0,%r7,__PT_R0(%r11)
@@ -422,13 +427,12 @@
stg %r10,__PT_ARGS(%r11)
tm __LC_PGM_ILC+3,0x80 # check for per exception
jz 0f
- lg %r1,__TI_task(%r12)
tmhh %r8,0x0001 # kernel per event ?
jz pgm_kprobe
oi __TI_flags+7(%r12),_TIF_PER_TRAP
- mvc __THREAD_per_address(8,%r1),__LC_PER_ADDRESS
- mvc __THREAD_per_cause(2,%r1),__LC_PER_CAUSE
- mvc __THREAD_per_paid(1,%r1),__LC_PER_PAID
+ mvc __THREAD_per_address(8,%r14),__LC_PER_ADDRESS
+ mvc __THREAD_per_cause(2,%r14),__LC_PER_CAUSE
+ mvc __THREAD_per_paid(1,%r14),__LC_PER_PAID
0: REENABLE_IRQS
xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
larl %r1,pgm_check_table