From b21e023ba4003fe4b5c32540e4aee5991c019e92 Mon Sep 17 00:00:00 2001 From: Rabin Vincent Date: Tue, 2 Apr 2013 22:11:46 +0100 Subject: ARM: 7689/1: add unwind annotations to ftrace asm Add unwind annotations to the ftrace assembly code so that the function tracer's stacktracing options (func_stack_trace, etc.) work when CONFIG_ARM_UNWIND is enabled. Signed-off-by: Rabin Vincent Signed-off-by: Russell King --- arch/arm/kernel/entry-common.S | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'arch/arm/kernel/entry-common.S') diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S index 3248cde504ed..fefd7f971437 100644 --- a/arch/arm/kernel/entry-common.S +++ b/arch/arm/kernel/entry-common.S @@ -276,7 +276,13 @@ ENDPROC(ftrace_graph_caller_old) */ .macro mcount_enter +/* + * This pad compensates for the push {lr} at the call site. Note that we are + * unable to unwind through a function which does not otherwise save its lr. + */ + UNWIND(.pad #4) stmdb sp!, {r0-r3, lr} + UNWIND(.save {r0-r3, lr}) .endm .macro mcount_get_lr reg @@ -289,6 +295,7 @@ ENDPROC(ftrace_graph_caller_old) .endm ENTRY(__gnu_mcount_nc) +UNWIND(.fnstart) #ifdef CONFIG_DYNAMIC_FTRACE mov ip, lr ldmia sp!, {lr} @@ -296,17 +303,22 @@ ENTRY(__gnu_mcount_nc) #else __mcount #endif +UNWIND(.fnend) ENDPROC(__gnu_mcount_nc) #ifdef CONFIG_DYNAMIC_FTRACE ENTRY(ftrace_caller) +UNWIND(.fnstart) __ftrace_caller +UNWIND(.fnend) ENDPROC(ftrace_caller) #endif #ifdef CONFIG_FUNCTION_GRAPH_TRACER ENTRY(ftrace_graph_caller) +UNWIND(.fnstart) __ftrace_graph_caller +UNWIND(.fnend) ENDPROC(ftrace_graph_caller) #endif -- cgit v1.2.3 From 651e94995ed5c10d77adcf19edb9de7d6f0cac3e Mon Sep 17 00:00:00 2001 From: Russell King Date: Thu, 28 Mar 2013 11:44:25 +0000 Subject: ARM: entry-common: get rid of unnecessary ifdefs The contents of the asm_trace_hardirqs_on is already conditional on CONFIG_TRACE_IRQFLAGS. There's little point also making the use of the macro conditional as well. Get rid of these ifdefs to make the code easier to read. Signed-off-by: Russell King --- arch/arm/kernel/entry-common.S | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) (limited to 'arch/arm/kernel/entry-common.S') diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S index 3248cde504ed..6f37ddfadbfa 100644 --- a/arch/arm/kernel/entry-common.S +++ b/arch/arm/kernel/entry-common.S @@ -35,9 +35,7 @@ ret_fast_syscall: ldr r1, [tsk, #TI_FLAGS] tst r1, #_TIF_WORK_MASK bne fast_work_pending -#if defined(CONFIG_IRQSOFF_TRACER) asm_trace_hardirqs_on -#endif /* perform architecture specific actions before user return */ arch_ret_to_user r1, lr @@ -71,9 +69,8 @@ ENTRY(ret_to_user_from_irq) tst r1, #_TIF_WORK_MASK bne work_pending no_work_pending: -#if defined(CONFIG_IRQSOFF_TRACER) asm_trace_hardirqs_on -#endif + /* perform architecture specific actions before user return */ arch_ret_to_user r1, lr -- cgit v1.2.3 From b00884802043d9102ecc2abfdc37a7b35b30e52a Mon Sep 17 00:00:00 2001 From: Kevin Hilman Date: Thu, 28 Mar 2013 22:54:40 +0100 Subject: ARM: 7688/1: add support for context tracking subsystem commit 91d1aa43 (context_tracking: New context tracking susbsystem) generalized parts of the RCU userspace extended quiescent state into the context tracking subsystem. Context tracking is then used to implement adaptive tickless (a.k.a extended nohz) To support the new context tracking subsystem on ARM, the user/kernel boundary transtions need to be instrumented. For exceptions and IRQs in usermode, the existing usr_entry macro is used to instrument the user->kernel transition. For the return to usermode path, the ret_to_user* path is instrumented. Using the usr_entry macro, this covers interrupts in userspace, data abort and prefetch abort exceptions in userspace as well as undefined exceptions in userspace (which is where FP emulation and VFP are handled.) For syscalls, the slow return path is covered by instrumenting the ret_to_user path. In addition, the syscall entry point is instrumented which covers the user->kernel transition for both fast and slow syscalls, and an additional instrumentation point is added for the fast syscall return path (ret_fast_syscall). Cc: Mats Liljegren Cc: Frederic Weisbecker Signed-off-by: Kevin Hilman Signed-off-by: Russell King --- arch/arm/Kconfig | 1 + arch/arm/include/asm/thread_info.h | 1 + arch/arm/kernel/entry-armv.S | 1 + arch/arm/kernel/entry-common.S | 3 +++ arch/arm/kernel/entry-header.S | 28 ++++++++++++++++++++++++++++ 5 files changed, 34 insertions(+) (limited to 'arch/arm/kernel/entry-common.S') diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 5b714695b01b..7dc4cabc34d7 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -59,6 +59,7 @@ config ARM select CLONE_BACKWARDS select OLD_SIGSUSPEND3 select OLD_SIGACTION + select HAVE_CONTEXT_TRACKING help The ARM series is a line of low-power-consumption RISC chip designs licensed by ARM Ltd and targeted at embedded applications and diff --git a/arch/arm/include/asm/thread_info.h b/arch/arm/include/asm/thread_info.h index cddda1f41f0f..1995d1a84060 100644 --- a/arch/arm/include/asm/thread_info.h +++ b/arch/arm/include/asm/thread_info.h @@ -152,6 +152,7 @@ extern int vfp_restore_user_hwstate(struct user_vfp __user *, #define TIF_SYSCALL_AUDIT 9 #define TIF_SYSCALL_TRACEPOINT 10 #define TIF_SECCOMP 11 /* seccomp syscall filtering active */ +#define TIF_NOHZ 12 /* in adaptive nohz mode */ #define TIF_USING_IWMMXT 17 #define TIF_MEMDIE 18 /* is terminating due to OOM killer */ #define TIF_RESTORE_SIGMASK 20 diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S index 0f82098c9bfe..2b1de1b2f132 100644 --- a/arch/arm/kernel/entry-armv.S +++ b/arch/arm/kernel/entry-armv.S @@ -396,6 +396,7 @@ ENDPROC(__pabt_svc) #ifdef CONFIG_IRQSOFF_TRACER bl trace_hardirqs_off #endif + ct_user_exit save = 0 .endm .macro kuser_cmpxchg_check diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S index 3248cde504ed..469e82b3f757 100644 --- a/arch/arm/kernel/entry-common.S +++ b/arch/arm/kernel/entry-common.S @@ -41,6 +41,7 @@ ret_fast_syscall: /* perform architecture specific actions before user return */ arch_ret_to_user r1, lr + ct_user_enter restore_user_regs fast = 1, offset = S_OFF UNWIND(.fnend ) @@ -76,6 +77,7 @@ no_work_pending: #endif /* perform architecture specific actions before user return */ arch_ret_to_user r1, lr + ct_user_enter save = 0 restore_user_regs fast = 0, offset = 0 ENDPROC(ret_to_user_from_irq) @@ -394,6 +396,7 @@ ENTRY(vector_swi) mcr p15, 0, ip, c1, c0 @ update control register #endif enable_irq + ct_user_exit get_thread_info tsk adr tbl, sys_call_table @ load syscall table pointer diff --git a/arch/arm/kernel/entry-header.S b/arch/arm/kernel/entry-header.S index 9a8531eadd3d..782a94956286 100644 --- a/arch/arm/kernel/entry-header.S +++ b/arch/arm/kernel/entry-header.S @@ -163,6 +163,34 @@ .endm #endif /* !CONFIG_THUMB2_KERNEL */ +/* + * Context tracking subsystem. Used to instrument transitions + * between user and kernel mode. + */ + .macro ct_user_exit, save = 1 +#ifdef CONFIG_CONTEXT_TRACKING + .if \save + stmdb sp!, {r0-r3, ip, lr} + bl user_exit + ldmia sp!, {r0-r3, ip, lr} + .else + bl user_exit + .endif +#endif + .endm + + .macro ct_user_enter, save = 1 +#ifdef CONFIG_CONTEXT_TRACKING + .if \save + stmdb sp!, {r0-r3, ip, lr} + bl user_enter + ldmia sp!, {r0-r3, ip, lr} + .else + bl user_enter + .endif +#endif + .endm + /* * These are the registers used in the syscall handler, and allow us to * have in theory up to 7 arguments to a function - r0 to r6. -- cgit v1.2.3