csky: Fixup add zero_fp fixup perf backtrace panic
We need set fp zero to let backtrace know the end. The patch fixup perf
callchain panic problem, because backtrace didn't know what is the end
of fp.
Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Reported-by: Mao Han <han_mao@c-sky.com>
diff --git a/arch/csky/kernel/entry.S b/arch/csky/kernel/entry.S
index a7e84cc..564dab2 100644
--- a/arch/csky/kernel/entry.S
+++ b/arch/csky/kernel/entry.S
@@ -17,6 +17,12 @@
#define PTE_INDX_SHIFT 10
#define _PGDIR_SHIFT 22
+.macro zero_fp
+#ifdef CONFIG_STACKTRACE
+ movi r8, 0
+#endif
+.endm
+
.macro tlbop_begin name, val0, val1, val2
ENTRY(csky_\name)
mtcr a3, ss2
@@ -96,6 +102,7 @@
SAVE_ALL 0
.endm
.macro tlbop_end is_write
+ zero_fp
RD_MEH a2
psrset ee, ie
mov a0, sp
@@ -120,6 +127,7 @@
ENTRY(csky_systemcall)
SAVE_ALL TRAP0_SIZE
+ zero_fp
psrset ee, ie
@@ -136,9 +144,9 @@
mov r9, sp
bmaski r10, THREAD_SHIFT
andn r9, r10
- ldw r8, (r9, TINFO_FLAGS)
- ANDI_R3 r8, (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_TRACEPOINT | _TIF_SYSCALL_AUDIT)
- cmpnei r8, 0
+ ldw r12, (r9, TINFO_FLAGS)
+ ANDI_R3 r12, (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_TRACEPOINT | _TIF_SYSCALL_AUDIT)
+ cmpnei r12, 0
bt csky_syscall_trace
#if defined(__CSKYABIV2__)
subi sp, 8
@@ -180,7 +188,7 @@
ENTRY(ret_from_kernel_thread)
jbsr schedule_tail
- mov a0, r8
+ mov a0, r10
jsr r9
jbsr ret_from_exception
@@ -189,9 +197,9 @@
mov r9, sp
bmaski r10, THREAD_SHIFT
andn r9, r10
- ldw r8, (r9, TINFO_FLAGS)
- ANDI_R3 r8, (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_TRACEPOINT | _TIF_SYSCALL_AUDIT)
- cmpnei r8, 0
+ ldw r12, (r9, TINFO_FLAGS)
+ ANDI_R3 r12, (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_TRACEPOINT | _TIF_SYSCALL_AUDIT)
+ cmpnei r12, 0
bf ret_from_exception
mov a0, sp /* sp = pt_regs pointer */
jbsr syscall_trace_exit
@@ -209,9 +217,9 @@
bmaski r10, THREAD_SHIFT
andn r9, r10
- ldw r8, (r9, TINFO_FLAGS)
- andi r8, (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED)
- cmpnei r8, 0
+ ldw r12, (r9, TINFO_FLAGS)
+ andi r12, (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED)
+ cmpnei r12, 0
bt exit_work
1:
RESTORE_ALL
@@ -220,11 +228,11 @@
lrw syscallid, ret_from_exception
mov lr, syscallid
- btsti r8, TIF_NEED_RESCHED
+ btsti r12, TIF_NEED_RESCHED
bt work_resched
mov a0, sp
- mov a1, r8
+ mov a1, r12
jmpi do_notify_resume
work_resched:
@@ -232,6 +240,7 @@
ENTRY(csky_trap)
SAVE_ALL 0
+ zero_fp
psrset ee
mov a0, sp /* Push Stack pointer arg */
jbsr trap_c /* Call C-level trap handler */
@@ -265,6 +274,7 @@
ENTRY(csky_irq)
SAVE_ALL 0
+ zero_fp
psrset ee
#ifdef CONFIG_PREEMPT
@@ -276,21 +286,21 @@
* Get task_struct->stack.preempt_count for current,
* and increase 1.
*/
- ldw r8, (r9, TINFO_PREEMPT)
- addi r8, 1
- stw r8, (r9, TINFO_PREEMPT)
+ ldw r12, (r9, TINFO_PREEMPT)
+ addi r12, 1
+ stw r12, (r9, TINFO_PREEMPT)
#endif
mov a0, sp
jbsr csky_do_IRQ
#ifdef CONFIG_PREEMPT
- subi r8, 1
- stw r8, (r9, TINFO_PREEMPT)
- cmpnei r8, 0
+ subi r12, 1
+ stw r12, (r9, TINFO_PREEMPT)
+ cmpnei r12, 0
bt 2f
- ldw r8, (r9, TINFO_FLAGS)
- btsti r8, TIF_NEED_RESCHED
+ ldw r12, (r9, TINFO_FLAGS)
+ btsti r12, TIF_NEED_RESCHED
bf 2f
1:
jbsr preempt_schedule_irq /* irq en/disable is done inside */
diff --git a/arch/csky/kernel/process.c b/arch/csky/kernel/process.c
index e555740..f320d92 100644
--- a/arch/csky/kernel/process.c
+++ b/arch/csky/kernel/process.c
@@ -55,7 +55,7 @@ int copy_thread(unsigned long clone_flags,
if (unlikely(p->flags & PF_KTHREAD)) {
memset(childregs, 0, sizeof(struct pt_regs));
childstack->r15 = (unsigned long) ret_from_kernel_thread;
- childstack->r8 = kthread_arg;
+ childstack->r10 = kthread_arg;
childstack->r9 = usp;
childregs->sr = mfcr("psr");
} else {