Commit 0dafafc3 authored by Vineet Gupta's avatar Vineet Gupta
Browse files

ARC: Add support for irqflags tracing and lockdep 



Lockdep required a small fix to stacktrace API which was incorrectly
unwindign out of __switch_to for the current call frame.

Signed-off-by: default avatarVineet Gupta <vgupta@synopsys.com>
parent 54c8bff1

arch/arc/Kconfig

+6 −0
Original line number Diff line number Diff line
@@ -35,6 +35,12 @@ config ARC 
	select PERF_USE_VMALLOC

	select HAVE_DEBUG_STACKOVERFLOW



config TRACE_IRQFLAGS_SUPPORT

	def_bool y



config LOCKDEP_SUPPORT

	def_bool y



config SCHED_OMIT_FRAME_POINTER

	def_bool y

arch/arc/include/asm/irqflags.h

+22 −0
Original line number Diff line number Diff line
@@ -151,16 +151,38 @@ static inline void arch_unmask_irq(unsigned int irq) 


#else



#ifdef CONFIG_TRACE_IRQFLAGS



.macro TRACE_ASM_IRQ_DISABLE

	bl	trace_hardirqs_off

.endm



.macro TRACE_ASM_IRQ_ENABLE

	bl	trace_hardirqs_on

.endm



#else



.macro TRACE_ASM_IRQ_DISABLE

.endm



.macro TRACE_ASM_IRQ_ENABLE

.endm



#endif



.macro IRQ_DISABLE  scratch

	lr	\scratch, [status32]

	bic	\scratch, \scratch, (STATUS_E1_MASK | STATUS_E2_MASK)

	flag	\scratch

	TRACE_ASM_IRQ_DISABLE

.endm



.macro IRQ_ENABLE  scratch

	lr	\scratch, [status32]

	or	\scratch, \scratch, (STATUS_E1_MASK | STATUS_E2_MASK)

	flag	\scratch

	TRACE_ASM_IRQ_ENABLE

.endm



#endif	/* __ASSEMBLY__ */

arch/arc/kernel/entry.S

+11 −0
Original line number Diff line number Diff line
@@ -250,6 +250,14 @@ ARC_ENTRY handle_interrupt_level1 
	lr  r0, [icause1]

	and r0, r0, 0x1f



#ifdef CONFIG_TRACE_IRQFLAGS

	; icause1 needs to be read early, before calling tracing, which

	; can clobber scratch regs, hence use of stack to stash it

	push r0

	TRACE_ASM_IRQ_DISABLE

	pop  r0

#endif



	bl.d  @arch_do_IRQ

	mov r1, sp
@@ -570,6 +578,7 @@ resume_user_mode_begin: 
	; --- (Slow Path #2) pending signal  ---

	mov r0, sp	; pt_regs for arg to do_signal()/do_notify_resume()



	GET_CURR_THR_INFO_FLAGS   r9

	bbit0  r9, TIF_SIGPENDING, .Lchk_notify_resume



	; Normal Trap/IRQ entry only saves Scratch (caller-saved) regs
@@ -635,6 +644,8 @@ resume_kernel_mode: 


restore_regs :



	TRACE_ASM_IRQ_ENABLE



	lr	r10, [status32]



	; Restore REG File. In case multiple Events outstanding,

arch/arc/kernel/stacktrace.c

+3 −1
Original line number Diff line number Diff line
@@ -237,11 +237,13 @@ unsigned int get_wchan(struct task_struct *tsk) 
 */

void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)

{

	/* Assumes @tsk is sleeping so unwinds from __switch_to */

	arc_unwind_core(tsk, NULL, __collect_all_but_sched, trace);

}



void save_stack_trace(struct stack_trace *trace)

{

	arc_unwind_core(current, NULL, __collect_all, trace);

	/* Pass NULL for task so it unwinds the current call frame */

	arc_unwind_core(NULL, NULL, __collect_all, trace);

}

#endif