Commit a93751ca authored by Markus Metzger's avatar Markus Metzger Committed by Ingo Molnar
Browse files

x86, bts, ftrace: adapt the hw-branch-tracer to the ds.c interface 



Impact: restructure code, cleanup

Remove BTS bits from the hw-branch-tracer (renamed from bts-tracer) and
use the ds interface.

Signed-off-by: default avatarMarkus Metzger <markut.t.metzger@intel.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent c2724775

kernel/trace/Kconfig

+2 −2
Original line number Diff line number Diff line
@@ -251,9 +251,9 @@ config STACK_TRACER 


	  Say N if unsure.



config BTS_TRACER

config HW_BRANCH_TRACER

	depends on HAVE_HW_BRANCH_TRACER

	bool "Trace branches"

	bool "Trace hw branches"

	select TRACING

	help

	  This tracer records all branches on the system in a circular

kernel/trace/Makefile

+1 −1
Original line number Diff line number Diff line
@@ -31,7 +31,7 @@ obj-$(CONFIG_MMIOTRACE) += trace_mmiotrace.o 
obj-$(CONFIG_BOOT_TRACER) += trace_boot.o

obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += trace_functions_graph.o

obj-$(CONFIG_TRACE_BRANCH_PROFILING) += trace_branch.o

obj-$(CONFIG_BTS_TRACER) += trace_bts.o

obj-$(CONFIG_HW_BRANCH_TRACER) += trace_hw_branches.o

obj-$(CONFIG_POWER_TRACER) += trace_power.o



libftrace-y := ftrace.o

kernel/trace/trace.h

+6 −8
Original line number Diff line number Diff line
@@ -28,7 +28,7 @@ enum trace_type { 
	TRACE_GRAPH_RET,

	TRACE_GRAPH_ENT,

	TRACE_USER_STACK,

	TRACE_BTS,

	TRACE_HW_BRANCHES,

	TRACE_POWER,



	__TRACE_LAST_TYPE
@@ -159,10 +159,10 @@ struct trace_branch { 
	char			correct;

};



struct bts_entry {

struct hw_branch_entry {

	struct trace_entry	ent;

	unsigned long		from;

	unsigned long		to;

	u64			from;

	u64			to;

};



struct trace_power {
@@ -278,7 +278,7 @@ extern void __ftrace_bad_type(void); 
			  TRACE_GRAPH_ENT);		\

		IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,	\

			  TRACE_GRAPH_RET);		\

		IF_ASSIGN(var, ent, struct bts_entry, TRACE_BTS);\

		IF_ASSIGN(var, ent, struct hw_branch_entry, TRACE_HW_BRANCHES);\

 		IF_ASSIGN(var, ent, struct trace_power, TRACE_POWER); \

		__ftrace_bad_type();					\

	} while (0)
@@ -414,9 +414,7 @@ void trace_function(struct trace_array *tr, 


void trace_graph_return(struct ftrace_graph_ret *trace);

int trace_graph_entry(struct ftrace_graph_ent *trace);

void trace_bts(struct trace_array *tr,

	       unsigned long from,

	       unsigned long to);

void trace_hw_branch(struct trace_array *tr, u64 from, u64 to);



void tracing_start_cmdline_record(void);

void tracing_stop_cmdline_record(void);

kernel/trace/trace_bts.c→kernel/trace/trace_hw_branches.c

+46 −117
Original line number Diff line number Diff line 
/*

 * BTS tracer

 * h/w branch tracer for x86 based on bts

 *

 * Copyright (C) 2008 Markus Metzger <markus.t.metzger@gmail.com>

 *
@@ -25,68 +25,6 @@ static DEFINE_PER_CPU(unsigned char[SIZEOF_BTS], buffer); 
#define this_buffer per_cpu(buffer, smp_processor_id())





/*

 * Information to interpret a BTS record.

 * This will go into an in-kernel BTS interface.

 */

static unsigned char sizeof_field;

static unsigned long debugctl_mask;



#define sizeof_bts (3 * sizeof_field)



static void bts_trace_cpuinit(struct cpuinfo_x86 *c)

{

	switch (c->x86) {

	case 0x6:

		switch (c->x86_model) {

		case 0x0 ... 0xC:

			break;

		case 0xD:

		case 0xE: /* Pentium M */

			sizeof_field = sizeof(long);

			debugctl_mask = (1<<6)|(1<<7);

			break;

		default:

			sizeof_field = 8;

			debugctl_mask = (1<<6)|(1<<7);

			break;

		}

		break;

	case 0xF:

		switch (c->x86_model) {

		case 0x0:

		case 0x1:

		case 0x2: /* Netburst */

			sizeof_field = sizeof(long);

			debugctl_mask = (1<<2)|(1<<3);

			break;

		default:

			/* sorry, don't know about them */

			break;

		}

		break;

	default:

		/* sorry, don't know about them */

		break;

	}

}



static inline void bts_enable(void)

{

	unsigned long debugctl;



	rdmsrl(MSR_IA32_DEBUGCTLMSR, debugctl);

	wrmsrl(MSR_IA32_DEBUGCTLMSR, debugctl | debugctl_mask);

}



static inline void bts_disable(void)

{

	unsigned long debugctl;



	rdmsrl(MSR_IA32_DEBUGCTLMSR, debugctl);

	wrmsrl(MSR_IA32_DEBUGCTLMSR, debugctl & ~debugctl_mask);

}



static void bts_trace_reset(struct trace_array *tr)

{

	int cpu;
@@ -99,15 +37,17 @@ static void bts_trace_reset(struct trace_array *tr) 


static void bts_trace_start_cpu(void *arg)

{

	if (this_tracer)

		ds_release_bts(this_tracer);



	this_tracer =

		ds_request_bts(/* task = */ NULL, this_buffer, SIZEOF_BTS,

			       /* ovfl = */ NULL, /* th = */ (size_t)-1);

			       /* ovfl = */ NULL, /* th = */ (size_t)-1,

			       BTS_KERNEL);

	if (IS_ERR(this_tracer)) {

		this_tracer = NULL;

		return;

	}



	bts_enable();

}



static void bts_trace_start(struct trace_array *tr)
@@ -123,8 +63,6 @@ static void bts_trace_start(struct trace_array *tr) 
static void bts_trace_stop_cpu(void *arg)

{

	if (this_tracer) {

		bts_disable();



		ds_release_bts(this_tracer);

		this_tracer = NULL;

	}
@@ -140,7 +78,6 @@ static void bts_trace_stop(struct trace_array *tr) 


static int bts_trace_init(struct trace_array *tr)

{

	bts_trace_cpuinit(&boot_cpu_data);

	bts_trace_reset(tr);

	bts_trace_start(tr);
@@ -149,47 +86,37 @@ static int bts_trace_init(struct trace_array *tr) 


static void bts_trace_print_header(struct seq_file *m)

{

#ifdef __i386__

	seq_puts(m, "# CPU#    FROM           TO     FUNCTION\n");

	seq_puts(m, "#  |       |             |         |\n");

#else

	seq_puts(m,

		 "# CPU#        FROM                   TO         FUNCTION\n");

	seq_puts(m,

		 "#  |           |                     |             |\n");

#endif

}



static enum print_line_t bts_trace_print_line(struct trace_iterator *iter)

{

	struct trace_entry *entry = iter->ent;

	struct trace_seq *seq = &iter->seq;

	struct bts_entry *it;

	struct hw_branch_entry *it;



	trace_assign_type(it, entry);



	if (entry->type == TRACE_BTS) {

		int ret;

#ifdef CONFIG_KALLSYMS

		char function[KSYM_SYMBOL_LEN];

		sprint_symbol(function, it->from);

#else

		char *function = "<unknown>";

#endif



		ret = trace_seq_printf(seq, "%4d  0x%lx -> 0x%lx [%s]\n",

				       entry->cpu, it->from, it->to, function);

		if (!ret)

			return TRACE_TYPE_PARTIAL_LINE;;

	if (entry->type == TRACE_HW_BRANCHES) {

		if (trace_seq_printf(seq, "%4d  ", entry->cpu) &&

		    trace_seq_printf(seq, "0x%016llx -> 0x%016llx ",

				     it->from, it->to) &&

		    (!it->from ||

		     seq_print_ip_sym(seq, it->from, /* sym_flags = */ 0)) &&

		    trace_seq_printf(seq, "\n"))

			return TRACE_TYPE_HANDLED;

		return TRACE_TYPE_PARTIAL_LINE;;

	}

	return TRACE_TYPE_UNHANDLED;

}



void trace_bts(struct trace_array *tr, unsigned long from, unsigned long to)

void trace_hw_branch(struct trace_array *tr, u64 from, u64 to)

{

	struct ring_buffer_event *event;

	struct bts_entry *entry;

	struct hw_branch_entry *entry;

	unsigned long irq;



	event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry), &irq);
@@ -197,56 +124,58 @@ void trace_bts(struct trace_array *tr, unsigned long from, unsigned long to) 
		return;

	entry	= ring_buffer_event_data(event);

	tracing_generic_entry_update(&entry->ent, 0, from);

	entry->ent.type = TRACE_BTS;

	entry->ent.type = TRACE_HW_BRANCHES;

	entry->ent.cpu = smp_processor_id();

	entry->from = from;

	entry->to   = to;

	ring_buffer_unlock_commit(tr->buffer, event, irq);

}



static void trace_bts_at(struct trace_array *tr, size_t index)

static void trace_bts_at(struct trace_array *tr,

			 const struct bts_trace *trace, void *at)

{

	const void *raw = NULL;

	unsigned long from, to;

	int err;

	struct bts_struct bts;

	int err = 0;



	err = ds_access_bts(this_tracer, index, &raw);

	if (err < 0)

	WARN_ON_ONCE(!trace->read);

	if (!trace->read)

		return;



	from = *(const unsigned long *)raw;

	to = *(const unsigned long *)((const char *)raw + sizeof_field);

	err = trace->read(this_tracer, at, &bts);

	if (err < 0)

		return;



	trace_bts(tr, from, to);

	switch (bts.qualifier) {

	case BTS_BRANCH:

		trace_hw_branch(tr, bts.variant.lbr.from, bts.variant.lbr.to);

		break;

	}

}



static void trace_bts_cpu(void *arg)

{

	struct trace_array *tr = (struct trace_array *) arg;

	size_t index = 0, end = 0, i;

	int err;

	const struct bts_trace *trace;

	unsigned char *at;



	if (!this_tracer)

		return;



	bts_disable();



	err = ds_get_bts_index(this_tracer, &index);

	if (err < 0)

		goto out;



	err = ds_get_bts_end(this_tracer, &end);

	if (err < 0)

	ds_suspend_bts(this_tracer);

	trace = ds_read_bts(this_tracer);

	if (!trace)

		goto out;



	for (i = index; i < end; i++)

		trace_bts_at(tr, i);

	for (at = trace->ds.top; (void *)at < trace->ds.end;

	     at += trace->ds.size)

		trace_bts_at(tr, trace, at);



	for (i = 0; i < index; i++)

		trace_bts_at(tr, i);

	for (at = trace->ds.begin; (void *)at < trace->ds.top;

	     at += trace->ds.size)

		trace_bts_at(tr, trace, at);



out:

	bts_enable();

	ds_resume_bts(this_tracer);

}



static void trace_bts_prepare(struct trace_iterator *iter)
@@ -259,7 +188,7 @@ static void trace_bts_prepare(struct trace_iterator *iter) 


struct tracer bts_tracer __read_mostly =

{

	.name		= "bts",

	.name		= "hw-branch-tracer",

	.init		= bts_trace_init,

	.reset		= bts_trace_stop,

	.print_header	= bts_trace_print_header,

kernel/trace/trace.c

+1 −1

File changed.

Contains only whitespace changes.