From: Guo Ren <guoren@xxxxxxxxxxxxxxxxx>
This patch support context tracking with no hz full.
Here is the test result with dynticks-testing (see tick_stop):
cat /sys/kernel/debug/tracing/per_cpu/cpu0/trace
tracer: nop
entries-in-buffer/entries-written: 356/356 #P:1
_-----=> irqs-off
/ _----=> need-resched
| / _---=> hardirq/softirq
|| / _--=> preempt-depth
||| / delay
TASK-PID CPU# |||| TIMESTAMP FUNCTION
| | | |||| | |
...
sleep-192 [000] d.h. 167.088270: hrtimer_expire_entry: hrtimer=(ptrval) function=tick_sched_timer now=166436355700
sleep-192 [000] d.h. 167.092279: hrtimer_expire_entry: hrtimer=(ptrval) function=tick_sched_timer now=166440365700
<idle>-0 [000] d.h2 167.096492: hrtimer_expire_entry: hrtimer=(ptrval) function=tick_sched_timer now=166444578400
<idle>-0 [000] d..1 167.097876: tick_stop: success=1 dependency=NONE
^^^^^^^^^
<idle>-0 [000] d.h1 168.818206: hrtimer_expire_entry: hrtimer=(ptrval) function=tick_sched_timer now=168166280900
kworker/u2:0-7 [000] .... 168.821760: workqueue_execute_start: work struct (ptrval): function wb_workfn
kworker/u2:0-7 [000] d.h1 168.824464: hrtimer_expire_entry: hrtimer=(ptrval) function=tick_sched_timer now=168172547100
kworker/0:1-18 [000] .... 168.825053: workqueue_execute_start: work struct (ptrval): function vmstat_update
kworker/0:1-18 [000] .... 168.825238: workqueue_execute_start: work struct (ptrval): function vmstat_shepherd
kworker/0:1-18 [000] .... 168.825516: workqueue_execute_start: work struct (ptrval): function neigh_periodic_work
<idle>-0 [000] d..1 168.826121: tick_stop: success=1 dependency=NONE
kworker/u2:0-7 [000] .... 169.377327: workqueue_execute_start: work struct (ptrval): function flush_to_ldisc
<idle>-0 [000] d..1 169.379832: tick_stop: success=1 dependency=NONE
kworker/u2:0-7 [000] .... 169.607935: workqueue_execute_start: work struct (ptrval): function flush_to_ldisc
kworker/u2:0-7 [000] d.h1 169.608148: hrtimer_expire_entry: hrtimer=(ptrval) function=tick_sched_timer now=168956235500
<idle>-0 [000] d..1 169.608654: tick_stop: success=1 dependency=NONE
Signed-off-by: Guo Ren <guoren@xxxxxxxxxxxxxxxxx>
Cc: Greentime Hu <greentime.hu@xxxxxxxxxx>
Cc: Arnd Bergmann <arnd@xxxxxxxx>
---
arch/csky/Kconfig | 2 ++
arch/csky/kernel/entry.S | 23 +++++++++++++++++++++++
2 files changed, 25 insertions(+)
diff --git a/arch/csky/Kconfig b/arch/csky/Kconfig
index ad98b93..af23873 100644
--- a/arch/csky/Kconfig
+++ b/arch/csky/Kconfig
@@ -42,6 +42,8 @@ config CSKY
select HAVE_ARCH_MMAP_RND_BITS
select HAVE_ARCH_SECCOMP_FILTER
select HAVE_COPY_THREAD_TLS
+ select HAVE_CONTEXT_TRACKING
+ select HAVE_VIRT_CPU_ACCOUNTING_GEN
select HAVE_DEBUG_BUGVERBOSE
select HAVE_DYNAMIC_FTRACE
select HAVE_DYNAMIC_FTRACE_WITH_REGS
diff --git a/arch/csky/kernel/entry.S b/arch/csky/kernel/entry.S
index efd2e69..5936391 100644
--- a/arch/csky/kernel/entry.S
+++ b/arch/csky/kernel/entry.S
@@ -23,6 +23,22 @@
#endif
.endm
+.macro context_tracking
+ mfcr a0, epsr
+ btsti a0, 31
+ bt 1f
+ jbsr context_tracking_user_exit
+ ldw a0, (sp, LSAVE_A0)
+ ldw a1, (sp, LSAVE_A1)
+ ldw a2, (sp, LSAVE_A2)
+ ldw a3, (sp, LSAVE_A3)
+#if defined(__CSKYABIV1__)
+ ldw r6, (sp, LSAVE_A4)
+ ldw r7, (sp, LSAVE_A5)
+#endif
+1:
+.endm
+
.macro tlbop_begin name, val0, val1, val2
ENTRY(csky_\name)
mtcr a3, ss2
@@ -103,6 +119,7 @@ ENTRY(csky_\name)
.endm
.macro tlbop_end is_write
zero_fp
+ context_tracking
RD_MEH a2
psrset ee, ie
mov a0, sp
@@ -128,6 +145,7 @@ tlbop_end 1
ENTRY(csky_systemcall)
SAVE_ALL TRAP0_SIZE
zero_fp
+ context_tracking
psrset ee, ie
lrw r9, __NR_syscalls
@@ -237,6 +255,9 @@ ret_from_exception:
and r10, r9
cmpnei r10, 0
bt exit_work
+#ifdef CONFIG_CONTEXT_TRACKING
+ jbsr context_tracking_user_enter
+#endif
1:
#ifdef CONFIG_PREEMPTION
mov r9, sp
@@ -277,6 +298,7 @@ work_resched:
ENTRY(csky_trap)
SAVE_ALL 0
zero_fp
+ context_tracking
psrset ee
mov a0, sp /* Push Stack pointer arg */
jbsr trap_c /* Call C-level trap handler */
@@ -311,6 +333,7 @@ ENTRY(csky_get_tls)
ENTRY(csky_irq)
SAVE_ALL 0
zero_fp
+ context_tracking
psrset ee
#ifdef CONFIG_TRACE_IRQFLAGS
--
2.7.4
