David Daney wrote:
arch/mips/oprofile/common.c defines several symbols (op_model_mipsxx and
op_model_rm9000) with __attribute__((weak)). It then assumes that ELF
linking conventions will prevail and there will be no problems if they
are undefined.
The problem is if you try to load oprofile as a module. The kernel
module linker evidentially does not understand weak symbols and refuses
to load the module because they are undefined.
Perhaps a single
extern struct op_mips_model plat_op_model;
That must be defined by each different implementation. Deciding one
which implementation would then be done at compile time instead of runtime.
I don't have a patch for this yet, but that is what I am thinking of doing.
Ok, attached is my untested (but it compiles for some architectures) patch.
David Daney
diff --git a/arch/mips/oprofile/common.c b/arch/mips/oprofile/common.c
--- a/arch/mips/oprofile/common.c
+++ b/arch/mips/oprofile/common.c
@@ -14,20 +14,17 @@
#include "op_impl.h"
-extern struct op_mips_model op_model_mipsxx __attribute__((weak));
-extern struct op_mips_model op_model_rm9000 __attribute__((weak));
-
-static struct op_mips_model *model;
+extern struct op_mips_model *plat_op_model;
static struct op_counter_config ctr[20];
static int op_mips_setup(void)
{
/* Pre-compute the values to stuff in the hardware registers. */
- model->reg_setup(ctr);
+ plat_op_model->reg_setup(ctr);
/* Configure the registers on all cpus. */
- on_each_cpu(model->cpu_setup, 0, 0, 1);
+ on_each_cpu(plat_op_model->cpu_setup, 0, 0, 1);
return 0;
}
@@ -36,7 +33,7 @@ static int op_mips_create_files(struct s
{
int i;
- for (i = 0; i < model->num_counters; ++i) {
+ for (i = 0; i < plat_op_model->num_counters; ++i) {
struct dentry *dir;
char buf[3];
@@ -58,7 +55,7 @@ static int op_mips_create_files(struct s
static int op_mips_start(void)
{
- on_each_cpu(model->cpu_start, NULL, 0, 1);
+ on_each_cpu(plat_op_model->cpu_start, NULL, 0, 1);
return 0;
}
@@ -66,49 +63,33 @@ static int op_mips_start(void)
static void op_mips_stop(void)
{
/* Disable performance monitoring for all counters. */
- on_each_cpu(model->cpu_stop, NULL, 0, 1);
+ on_each_cpu(plat_op_model->cpu_stop, NULL, 0, 1);
}
int __init oprofile_arch_init(struct oprofile_operations *ops)
{
- struct op_mips_model *lmodel = NULL;
int res;
printk(KERN_INFO "oprofile: In oprofile_arch_init.\n");
- switch (current_cpu_data.cputype) {
- case CPU_24K:
- lmodel = &op_model_mipsxx;
- break;
-
- case CPU_RM9000:
- lmodel = &op_model_rm9000;
- break;
- };
-
- if (!lmodel)
- return -ENODEV;
-
- res = lmodel->init();
+ res = plat_op_model->init();
if (res)
return res;
- model = lmodel;
-
ops->create_files = op_mips_create_files;
ops->setup = op_mips_setup;
//ops->shutdown = op_mips_shutdown;
ops->start = op_mips_start;
ops->stop = op_mips_stop;
- ops->cpu_type = lmodel->cpu_type;
+ ops->cpu_type = plat_op_model->cpu_type;
printk(KERN_INFO "oprofile: using %s performance monitoring.\n",
- lmodel->cpu_type);
+ plat_op_model->cpu_type);
return 0;
}
void oprofile_arch_exit(void)
{
- model->exit();
+ plat_op_model->exit();
}
diff --git a/arch/mips/oprofile/op_model_mipsxx.c b/arch/mips/oprofile/op_model_mipsxx.c
--- a/arch/mips/oprofile/op_model_mipsxx.c
+++ b/arch/mips/oprofile/op_model_mipsxx.c
@@ -23,7 +23,7 @@
#define M_COUNTER_OVERFLOW (1UL << 31)
-struct op_mips_model op_model_mipsxx;
+static struct op_mips_model op_model_mipsxx;
static struct mipsxx_register_config {
unsigned int control[4];
@@ -205,7 +205,7 @@ static void mipsxx_exit(void)
perf_irq = null_perf_irq;
}
-struct op_mips_model op_model_mipsxx = {
+static struct op_mips_model op_model_mipsxx = {
.reg_setup = mipsxx_reg_setup,
.cpu_setup = mipsxx_cpu_setup,
.init = mipsxx_init,
@@ -213,3 +213,5 @@ struct op_mips_model op_model_mipsxx = {
.cpu_start = mipsxx_cpu_start,
.cpu_stop = mipsxx_cpu_stop,
};
+
+struct op_mips_model *plat_op_model = &op_model_mipsxx;
diff --git a/arch/mips/oprofile/op_model_rm9000.c b/arch/mips/oprofile/op_model_rm9000.c
--- a/arch/mips/oprofile/op_model_rm9000.c
+++ b/arch/mips/oprofile/op_model_rm9000.c
@@ -126,7 +126,7 @@ static void rm9000_exit(void)
free_irq(rm9000_perfcount_irq, NULL);
}
-struct op_mips_model op_model_rm9000 = {
+static struct op_mips_model op_model_rm9000 = {
.reg_setup = rm9000_reg_setup,
.cpu_setup = rm9000_cpu_setup,
.init = rm9000_init,
@@ -136,3 +136,5 @@ struct op_mips_model op_model_rm9000 = {
.cpu_type = "mips/rm9000",
.num_counters = 2
};
+
+struct op_mips_model *plat_op_model = &op_model_rm9000;
