From 0b6e4d56bf71866a2b58daa8323cf747988ce7e4 Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Tue, 28 Oct 2008 20:17:38 +0100 Subject: ftrace: perform an initialization for ftrace to enable it Impact: corrects a bug which made the non-dyn function tracer not functional With latest git, the non-dynamic function tracer didn't get any trace. The problem was the fact that ftrace_enabled wasn't initialized to 1 because ftrace hasn't any init function when DYNAMIC_FTRACE is disabled. So when a tracer tries to register an ftrace_ops struct, __register_ftrace_function failed to set the hook. This patch corrects it by setting an init function to initialize ftrace during the boot. Signed-off-by: Frederic Weisbecker Signed-off-by: Ingo Molnar --- kernel/trace/ftrace.c | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'kernel/trace') diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 7618c528756b..4a39d24568c8 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -1339,6 +1339,14 @@ void __init ftrace_init(void) } #else + +static int __init ftrace_nodyn_init(void) +{ + ftrace_enabled = 1; + return 0; +} +device_initcall(ftrace_nodyn_init); + # define ftrace_startup() do { } while (0) # define ftrace_shutdown() do { } while (0) # define ftrace_startup_sysctl() do { } while (0) -- cgit v1.2.2 From f3384b28a05624783b53836ccfed95ecde66a7ad Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 29 Oct 2008 11:15:57 -0400 Subject: ftrace: fix trace_nop config select Impact: build fix on non-function-tracing architectures The trace_nop is the tracer that is defined when no tracer is set in the ftrace infrastructure. The trace_nop was mistakenly selected by HAVE_FTRACE due to the confusion between ftrace infrastructure and the ftrace function tracer (which has been solved by renaming the function tracer). This patch changes the select to the approriate TRACING. This patch should fix compile errors on architectures that do not define the FUNCTION_TRACER. Signed-off-by: Steven Rostedt Signed-off-by: Ingo Molnar --- kernel/trace/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel/trace') diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index e0cea282e0c5..b58f43bec363 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -8,7 +8,6 @@ config NOP_TRACER config HAVE_FUNCTION_TRACER bool - select NOP_TRACER config HAVE_DYNAMIC_FTRACE bool @@ -28,6 +27,7 @@ config TRACING select RING_BUFFER select STACKTRACE select TRACEPOINTS + select NOP_TRACER menu "Tracers" -- cgit v1.2.2 From 9244489a7b69fe0746dc7cb3957f02e05bd1ceb0 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Fri, 24 Oct 2008 09:42:59 -0400 Subject: ftrace: handle archs that do not support irqs_disabled_flags Impact: build fix on non-lockdep architectures Some architectures do not support a way to read the irq flags that is set from "local_irq_save(flags)" to determine if interrupts were disabled or enabled. Ftrace uses this information to display to the user if the trace occurred with interrupts enabled or disabled. Besides the fact that those archs that do not support this will fail to compile, unless they fix it, we do not want to have the trace simply say interrupts were not disabled or they were enabled, without knowing the real answer. This patch adds a 'X' in the output to let the user know that the architecture they are running on does not support a way for the tracer to determine if interrupts were enabled or disabled. It also lets those same archs compile with tracing enabled. Signed-off-by: Steven Rostedt Signed-off-by: Ingo Molnar --- kernel/trace/trace.c | 7 ++++++- kernel/trace/trace.h | 20 +++++++++++--------- 2 files changed, 17 insertions(+), 10 deletions(-) (limited to 'kernel/trace') diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index a610ca771558..8a499e2adaec 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -656,7 +656,11 @@ tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, entry->preempt_count = pc & 0xff; entry->pid = (tsk) ? tsk->pid : 0; entry->flags = +#ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | +#else + TRACE_FLAG_IRQS_NOSUPPORT | +#endif ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); @@ -1244,7 +1248,8 @@ lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu) trace_seq_printf(s, "%8.8s-%-5d ", comm, entry->pid); trace_seq_printf(s, "%3d", cpu); trace_seq_printf(s, "%c%c", - (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' : '.', + (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' : + (entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ? 'X' : '.', ((entry->flags & TRACE_FLAG_NEED_RESCHED) ? 'N' : '.')); hardirq = entry->flags & TRACE_FLAG_HARDIRQ; diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 6889ca48f1f1..8465ad052707 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -120,18 +120,20 @@ struct trace_boot { /* * trace_flag_type is an enumeration that holds different * states when a trace occurs. These are: - * IRQS_OFF - interrupts were disabled - * NEED_RESCED - reschedule is requested - * HARDIRQ - inside an interrupt handler - * SOFTIRQ - inside a softirq handler - * CONT - multiple entries hold the trace item + * IRQS_OFF - interrupts were disabled + * IRQS_NOSUPPORT - arch does not support irqs_disabled_flags + * NEED_RESCED - reschedule is requested + * HARDIRQ - inside an interrupt handler + * SOFTIRQ - inside a softirq handler + * CONT - multiple entries hold the trace item */ enum trace_flag_type { TRACE_FLAG_IRQS_OFF = 0x01, - TRACE_FLAG_NEED_RESCHED = 0x02, - TRACE_FLAG_HARDIRQ = 0x04, - TRACE_FLAG_SOFTIRQ = 0x08, - TRACE_FLAG_CONT = 0x10, + TRACE_FLAG_IRQS_NOSUPPORT = 0x02, + TRACE_FLAG_NEED_RESCHED = 0x04, + TRACE_FLAG_HARDIRQ = 0x08, + TRACE_FLAG_SOFTIRQ = 0x10, + TRACE_FLAG_CONT = 0x20, }; #define TRACE_BUF_SIZE 1024 -- cgit v1.2.2