* [PATCH v2 2/5] rv: Merge struct rv_monitor_def into struct rv_monitor
2025-07-23 6:44 [PATCH v2 0/5] rv: Clean up & simplify Nam Cao
2025-07-23 6:44 ` [PATCH v2 1/5] rv: Remove unused field in struct rv_monitor_def Nam Cao
@ 2025-07-23 6:44 ` Nam Cao
2025-07-23 6:44 ` [PATCH v2 3/5] rv: Merge struct rv_reactor_def into struct rv_reactor Nam Cao
` (2 subsequent siblings)
4 siblings, 0 replies; 7+ messages in thread
From: Nam Cao @ 2025-07-23 6:44 UTC (permalink / raw)
To: Steven Rostedt, Masami Hiramatsu, Mathieu Desnoyers,
Gabriele Monaco, linux-trace-kernel, linux-kernel
Cc: Nam Cao
Each struct rv_monitor has a unique struct rv_monitor_def associated with
it. struct rv_monitor is statically allocated, while struct rv_monitor_def
is dynamically allocated.
This makes the code more complicated than it should be:
- Lookup is required to get the associated rv_monitor_def from rv_monitor
- Dynamic memory allocation is required for rv_monitor_def. This is
harder to get right compared to static memory. For instance, there is
an existing mistake: rv_unregister_monitor() does not free the memory
allocated by rv_register_monitor(). This is fortunately not a real
memory leak problem, as rv_unregister_monitor() is never called.
Simplify and merge rv_monitor_def into rv_monitor.
Reviewed-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Nam Cao <namcao@linutronix.de>
---
include/linux/rv.h | 8 ++
kernel/trace/rv/rv.c | 211 +++++++++++++++-------------------
kernel/trace/rv/rv.h | 27 ++---
kernel/trace/rv/rv_reactors.c | 62 +++++-----
4 files changed, 140 insertions(+), 168 deletions(-)
diff --git a/include/linux/rv.h b/include/linux/rv.h
index 97baf58d88b2..dba53aecdfab 100644
--- a/include/linux/rv.h
+++ b/include/linux/rv.h
@@ -7,6 +7,9 @@
#ifndef _LINUX_RV_H
#define _LINUX_RV_H
+#include <linux/types.h>
+#include <linux/list.h>
+
#define MAX_DA_NAME_LEN 32
#ifdef CONFIG_RV
@@ -98,8 +101,13 @@ struct rv_monitor {
void (*disable)(void);
void (*reset)(void);
#ifdef CONFIG_RV_REACTORS
+ struct rv_reactor_def *rdef;
__printf(1, 2) void (*react)(const char *msg, ...);
+ bool reacting;
#endif
+ struct list_head list;
+ struct rv_monitor *parent;
+ struct dentry *root_d;
};
bool rv_monitoring_on(void);
diff --git a/kernel/trace/rv/rv.c b/kernel/trace/rv/rv.c
index 108429d16ec1..6c0be2fdc52d 100644
--- a/kernel/trace/rv/rv.c
+++ b/kernel/trace/rv/rv.c
@@ -210,9 +210,9 @@ void rv_put_task_monitor_slot(int slot)
* Monitors with a parent are nested,
* Monitors without a parent could be standalone or containers.
*/
-bool rv_is_nested_monitor(struct rv_monitor_def *mdef)
+bool rv_is_nested_monitor(struct rv_monitor *mon)
{
- return mdef->parent != NULL;
+ return mon->parent != NULL;
}
/*
@@ -223,16 +223,16 @@ bool rv_is_nested_monitor(struct rv_monitor_def *mdef)
* for enable()/disable(). Use this condition to find empty containers.
* Keep both conditions in case we have some non-compliant containers.
*/
-bool rv_is_container_monitor(struct rv_monitor_def *mdef)
+bool rv_is_container_monitor(struct rv_monitor *mon)
{
- struct rv_monitor_def *next;
+ struct rv_monitor *next;
- if (list_is_last(&mdef->list, &rv_monitors_list))
+ if (list_is_last(&mon->list, &rv_monitors_list))
return false;
- next = list_next_entry(mdef, list);
+ next = list_next_entry(mon, list);
- return next->parent == mdef->monitor || !mdef->monitor->enable;
+ return next->parent == mon || !mon->enable;
}
/*
@@ -241,10 +241,10 @@ bool rv_is_container_monitor(struct rv_monitor_def *mdef)
static ssize_t monitor_enable_read_data(struct file *filp, char __user *user_buf, size_t count,
loff_t *ppos)
{
- struct rv_monitor_def *mdef = filp->private_data;
+ struct rv_monitor *mon = filp->private_data;
const char *buff;
- buff = mdef->monitor->enabled ? "1\n" : "0\n";
+ buff = mon->enabled ? "1\n" : "0\n";
return simple_read_from_buffer(user_buf, count, ppos, buff, strlen(buff)+1);
}
@@ -252,14 +252,14 @@ static ssize_t monitor_enable_read_data(struct file *filp, char __user *user_buf
/*
* __rv_disable_monitor - disabled an enabled monitor
*/
-static int __rv_disable_monitor(struct rv_monitor_def *mdef, bool sync)
+static int __rv_disable_monitor(struct rv_monitor *mon, bool sync)
{
lockdep_assert_held(&rv_interface_lock);
- if (mdef->monitor->enabled) {
- mdef->monitor->enabled = 0;
- if (mdef->monitor->disable)
- mdef->monitor->disable();
+ if (mon->enabled) {
+ mon->enabled = 0;
+ if (mon->disable)
+ mon->disable();
/*
* Wait for the execution of all events to finish.
@@ -273,90 +273,90 @@ static int __rv_disable_monitor(struct rv_monitor_def *mdef, bool sync)
return 0;
}
-static void rv_disable_single(struct rv_monitor_def *mdef)
+static void rv_disable_single(struct rv_monitor *mon)
{
- __rv_disable_monitor(mdef, true);
+ __rv_disable_monitor(mon, true);
}
-static int rv_enable_single(struct rv_monitor_def *mdef)
+static int rv_enable_single(struct rv_monitor *mon)
{
int retval;
lockdep_assert_held(&rv_interface_lock);
- if (mdef->monitor->enabled)
+ if (mon->enabled)
return 0;
- retval = mdef->monitor->enable();
+ retval = mon->enable();
if (!retval)
- mdef->monitor->enabled = 1;
+ mon->enabled = 1;
return retval;
}
-static void rv_disable_container(struct rv_monitor_def *mdef)
+static void rv_disable_container(struct rv_monitor *mon)
{
- struct rv_monitor_def *p = mdef;
+ struct rv_monitor *p = mon;
int enabled = 0;
list_for_each_entry_continue(p, &rv_monitors_list, list) {
- if (p->parent != mdef->monitor)
+ if (p->parent != mon)
break;
enabled += __rv_disable_monitor(p, false);
}
if (enabled)
tracepoint_synchronize_unregister();
- mdef->monitor->enabled = 0;
+ mon->enabled = 0;
}
-static int rv_enable_container(struct rv_monitor_def *mdef)
+static int rv_enable_container(struct rv_monitor *mon)
{
- struct rv_monitor_def *p = mdef;
+ struct rv_monitor *p = mon;
int retval = 0;
list_for_each_entry_continue(p, &rv_monitors_list, list) {
- if (retval || p->parent != mdef->monitor)
+ if (retval || p->parent != mon)
break;
retval = rv_enable_single(p);
}
if (retval)
- rv_disable_container(mdef);
+ rv_disable_container(mon);
else
- mdef->monitor->enabled = 1;
+ mon->enabled = 1;
return retval;
}
/**
* rv_disable_monitor - disable a given runtime monitor
- * @mdef: Pointer to the monitor definition structure.
+ * @mon: Pointer to the monitor definition structure.
*
* Returns 0 on success.
*/
-int rv_disable_monitor(struct rv_monitor_def *mdef)
+int rv_disable_monitor(struct rv_monitor *mon)
{
- if (rv_is_container_monitor(mdef))
- rv_disable_container(mdef);
+ if (rv_is_container_monitor(mon))
+ rv_disable_container(mon);
else
- rv_disable_single(mdef);
+ rv_disable_single(mon);
return 0;
}
/**
* rv_enable_monitor - enable a given runtime monitor
- * @mdef: Pointer to the monitor definition structure.
+ * @mon: Pointer to the monitor definition structure.
*
* Returns 0 on success, error otherwise.
*/
-int rv_enable_monitor(struct rv_monitor_def *mdef)
+int rv_enable_monitor(struct rv_monitor *mon)
{
int retval;
- if (rv_is_container_monitor(mdef))
- retval = rv_enable_container(mdef);
+ if (rv_is_container_monitor(mon))
+ retval = rv_enable_container(mon);
else
- retval = rv_enable_single(mdef);
+ retval = rv_enable_single(mon);
return retval;
}
@@ -367,7 +367,7 @@ int rv_enable_monitor(struct rv_monitor_def *mdef)
static ssize_t monitor_enable_write_data(struct file *filp, const char __user *user_buf,
size_t count, loff_t *ppos)
{
- struct rv_monitor_def *mdef = filp->private_data;
+ struct rv_monitor *mon = filp->private_data;
int retval;
bool val;
@@ -378,9 +378,9 @@ static ssize_t monitor_enable_write_data(struct file *filp, const char __user *u
mutex_lock(&rv_interface_lock);
if (val)
- retval = rv_enable_monitor(mdef);
+ retval = rv_enable_monitor(mon);
else
- retval = rv_disable_monitor(mdef);
+ retval = rv_disable_monitor(mon);
mutex_unlock(&rv_interface_lock);
@@ -399,12 +399,12 @@ static const struct file_operations interface_enable_fops = {
static ssize_t monitor_desc_read_data(struct file *filp, char __user *user_buf, size_t count,
loff_t *ppos)
{
- struct rv_monitor_def *mdef = filp->private_data;
+ struct rv_monitor *mon = filp->private_data;
char buff[256];
memset(buff, 0, sizeof(buff));
- snprintf(buff, sizeof(buff), "%s\n", mdef->monitor->description);
+ snprintf(buff, sizeof(buff), "%s\n", mon->description);
return simple_read_from_buffer(user_buf, count, ppos, buff, strlen(buff) + 1);
}
@@ -419,37 +419,37 @@ static const struct file_operations interface_desc_fops = {
* the monitor dir, where the specific options of the monitor
* are exposed.
*/
-static int create_monitor_dir(struct rv_monitor_def *mdef, struct rv_monitor_def *parent)
+static int create_monitor_dir(struct rv_monitor *mon, struct rv_monitor *parent)
{
struct dentry *root = parent ? parent->root_d : get_monitors_root();
- const char *name = mdef->monitor->name;
+ const char *name = mon->name;
struct dentry *tmp;
int retval;
- mdef->root_d = rv_create_dir(name, root);
- if (!mdef->root_d)
+ mon->root_d = rv_create_dir(name, root);
+ if (!mon->root_d)
return -ENOMEM;
- tmp = rv_create_file("enable", RV_MODE_WRITE, mdef->root_d, mdef, &interface_enable_fops);
+ tmp = rv_create_file("enable", RV_MODE_WRITE, mon->root_d, mon, &interface_enable_fops);
if (!tmp) {
retval = -ENOMEM;
goto out_remove_root;
}
- tmp = rv_create_file("desc", RV_MODE_READ, mdef->root_d, mdef, &interface_desc_fops);
+ tmp = rv_create_file("desc", RV_MODE_READ, mon->root_d, mon, &interface_desc_fops);
if (!tmp) {
retval = -ENOMEM;
goto out_remove_root;
}
- retval = reactor_populate_monitor(mdef);
+ retval = reactor_populate_monitor(mon);
if (retval)
goto out_remove_root;
return 0;
out_remove_root:
- rv_remove(mdef->root_d);
+ rv_remove(mon->root_d);
return retval;
}
@@ -458,13 +458,12 @@ static int create_monitor_dir(struct rv_monitor_def *mdef, struct rv_monitor_def
*/
static int monitors_show(struct seq_file *m, void *p)
{
- struct rv_monitor_def *mon_def = p;
+ struct rv_monitor *mon = p;
- if (mon_def->parent)
- seq_printf(m, "%s:%s\n", mon_def->parent->name,
- mon_def->monitor->name);
+ if (mon->parent)
+ seq_printf(m, "%s:%s\n", mon->parent->name, mon->name);
else
- seq_printf(m, "%s\n", mon_def->monitor->name);
+ seq_printf(m, "%s\n", mon->name);
return 0;
}
@@ -496,13 +495,13 @@ static void *available_monitors_next(struct seq_file *m, void *p, loff_t *pos)
*/
static void *enabled_monitors_next(struct seq_file *m, void *p, loff_t *pos)
{
- struct rv_monitor_def *m_def = p;
+ struct rv_monitor *mon = p;
(*pos)++;
- list_for_each_entry_continue(m_def, &rv_monitors_list, list) {
- if (m_def->monitor->enabled)
- return m_def;
+ list_for_each_entry_continue(mon, &rv_monitors_list, list) {
+ if (mon->enabled)
+ return mon;
}
return NULL;
@@ -510,7 +509,7 @@ static void *enabled_monitors_next(struct seq_file *m, void *p, loff_t *pos)
static void *enabled_monitors_start(struct seq_file *m, loff_t *pos)
{
- struct rv_monitor_def *m_def;
+ struct rv_monitor *mon;
loff_t l;
mutex_lock(&rv_interface_lock);
@@ -518,15 +517,15 @@ static void *enabled_monitors_start(struct seq_file *m, loff_t *pos)
if (list_empty(&rv_monitors_list))
return NULL;
- m_def = list_entry(&rv_monitors_list, struct rv_monitor_def, list);
+ mon = list_entry(&rv_monitors_list, struct rv_monitor, list);
for (l = 0; l <= *pos; ) {
- m_def = enabled_monitors_next(m, m_def, &l);
- if (!m_def)
+ mon = enabled_monitors_next(m, mon, &l);
+ if (!mon)
break;
}
- return m_def;
+ return mon;
}
/*
@@ -566,13 +565,13 @@ static const struct file_operations available_monitors_ops = {
*/
static void disable_all_monitors(void)
{
- struct rv_monitor_def *mdef;
+ struct rv_monitor *mon;
int enabled = 0;
mutex_lock(&rv_interface_lock);
- list_for_each_entry(mdef, &rv_monitors_list, list)
- enabled += __rv_disable_monitor(mdef, false);
+ list_for_each_entry(mon, &rv_monitors_list, list)
+ enabled += __rv_disable_monitor(mon, false);
if (enabled) {
/*
@@ -598,7 +597,7 @@ static ssize_t enabled_monitors_write(struct file *filp, const char __user *user
size_t count, loff_t *ppos)
{
char buff[MAX_RV_MONITOR_NAME_SIZE + 2];
- struct rv_monitor_def *mdef;
+ struct rv_monitor *mon;
int retval = -EINVAL;
bool enable = true;
char *ptr, *tmp;
@@ -633,17 +632,17 @@ static ssize_t enabled_monitors_write(struct file *filp, const char __user *user
if (tmp)
ptr = tmp+1;
- list_for_each_entry(mdef, &rv_monitors_list, list) {
- if (strcmp(ptr, mdef->monitor->name) != 0)
+ list_for_each_entry(mon, &rv_monitors_list, list) {
+ if (strcmp(ptr, mon->name) != 0)
continue;
/*
* Monitor found!
*/
if (enable)
- retval = rv_enable_monitor(mdef);
+ retval = rv_enable_monitor(mon);
else
- retval = rv_disable_monitor(mdef);
+ retval = rv_disable_monitor(mon);
if (!retval)
retval = count;
@@ -702,11 +701,11 @@ static void turn_monitoring_off(void)
static void reset_all_monitors(void)
{
- struct rv_monitor_def *mdef;
+ struct rv_monitor *mon;
- list_for_each_entry(mdef, &rv_monitors_list, list) {
- if (mdef->monitor->enabled && mdef->monitor->reset)
- mdef->monitor->reset();
+ list_for_each_entry(mon, &rv_monitors_list, list) {
+ if (mon->enabled && mon->reset)
+ mon->reset();
}
}
@@ -768,10 +767,10 @@ static const struct file_operations monitoring_on_fops = {
.read = monitoring_on_read_data,
};
-static void destroy_monitor_dir(struct rv_monitor_def *mdef)
+static void destroy_monitor_dir(struct rv_monitor *mon)
{
- reactor_cleanup_monitor(mdef);
- rv_remove(mdef->root_d);
+ reactor_cleanup_monitor(mon);
+ rv_remove(mon->root_d);
}
/**
@@ -783,7 +782,7 @@ static void destroy_monitor_dir(struct rv_monitor_def *mdef)
*/
int rv_register_monitor(struct rv_monitor *monitor, struct rv_monitor *parent)
{
- struct rv_monitor_def *r, *p = NULL;
+ struct rv_monitor *r;
int retval = 0;
if (strlen(monitor->name) >= MAX_RV_MONITOR_NAME_SIZE) {
@@ -795,49 +794,31 @@ int rv_register_monitor(struct rv_monitor *monitor, struct rv_monitor *parent)
mutex_lock(&rv_interface_lock);
list_for_each_entry(r, &rv_monitors_list, list) {
- if (strcmp(monitor->name, r->monitor->name) == 0) {
+ if (strcmp(monitor->name, r->name) == 0) {
pr_info("Monitor %s is already registered\n", monitor->name);
retval = -EEXIST;
goto out_unlock;
}
}
- if (parent) {
- list_for_each_entry(r, &rv_monitors_list, list) {
- if (strcmp(parent->name, r->monitor->name) == 0) {
- p = r;
- break;
- }
- }
- }
-
- if (p && rv_is_nested_monitor(p)) {
+ if (parent && rv_is_nested_monitor(parent)) {
pr_info("Parent monitor %s is already nested, cannot nest further\n",
parent->name);
retval = -EINVAL;
goto out_unlock;
}
- r = kzalloc(sizeof(struct rv_monitor_def), GFP_KERNEL);
- if (!r) {
- retval = -ENOMEM;
- goto out_unlock;
- }
-
- r->monitor = monitor;
- r->parent = parent;
+ monitor->parent = parent;
- retval = create_monitor_dir(r, p);
- if (retval) {
- kfree(r);
- goto out_unlock;
- }
+ retval = create_monitor_dir(monitor, parent);
+ if (retval)
+ return retval;
/* keep children close to the parent for easier visualisation */
- if (p)
- list_add(&r->list, &p->list);
+ if (parent)
+ list_add(&monitor->list, &parent->list);
else
- list_add_tail(&r->list, &rv_monitors_list);
+ list_add_tail(&monitor->list, &rv_monitors_list);
out_unlock:
mutex_unlock(&rv_interface_lock);
@@ -852,17 +833,11 @@ int rv_register_monitor(struct rv_monitor *monitor, struct rv_monitor *parent)
*/
int rv_unregister_monitor(struct rv_monitor *monitor)
{
- struct rv_monitor_def *ptr, *next;
-
mutex_lock(&rv_interface_lock);
- list_for_each_entry_safe(ptr, next, &rv_monitors_list, list) {
- if (strcmp(monitor->name, ptr->monitor->name) == 0) {
- rv_disable_monitor(ptr);
- list_del(&ptr->list);
- destroy_monitor_dir(ptr);
- }
- }
+ rv_disable_monitor(monitor);
+ list_del(&monitor->list);
+ destroy_monitor_dir(monitor);
mutex_unlock(&rv_interface_lock);
return 0;
diff --git a/kernel/trace/rv/rv.h b/kernel/trace/rv/rv.h
index 873364094402..f039ec1c9156 100644
--- a/kernel/trace/rv/rv.h
+++ b/kernel/trace/rv/rv.h
@@ -32,34 +32,23 @@ struct rv_reactor_def {
};
#endif
-struct rv_monitor_def {
- struct list_head list;
- struct rv_monitor *monitor;
- struct rv_monitor *parent;
- struct dentry *root_d;
-#ifdef CONFIG_RV_REACTORS
- struct rv_reactor_def *rdef;
- bool reacting;
-#endif
-};
-
struct dentry *get_monitors_root(void);
-int rv_disable_monitor(struct rv_monitor_def *mdef);
-int rv_enable_monitor(struct rv_monitor_def *mdef);
-bool rv_is_container_monitor(struct rv_monitor_def *mdef);
-bool rv_is_nested_monitor(struct rv_monitor_def *mdef);
+int rv_disable_monitor(struct rv_monitor *mon);
+int rv_enable_monitor(struct rv_monitor *mon);
+bool rv_is_container_monitor(struct rv_monitor *mon);
+bool rv_is_nested_monitor(struct rv_monitor *mon);
#ifdef CONFIG_RV_REACTORS
-int reactor_populate_monitor(struct rv_monitor_def *mdef);
-void reactor_cleanup_monitor(struct rv_monitor_def *mdef);
+int reactor_populate_monitor(struct rv_monitor *mon);
+void reactor_cleanup_monitor(struct rv_monitor *mon);
int init_rv_reactors(struct dentry *root_dir);
#else
-static inline int reactor_populate_monitor(struct rv_monitor_def *mdef)
+static inline int reactor_populate_monitor(struct rv_monitor *mon)
{
return 0;
}
-static inline void reactor_cleanup_monitor(struct rv_monitor_def *mdef)
+static inline void reactor_cleanup_monitor(struct rv_monitor *mon)
{
return;
}
diff --git a/kernel/trace/rv/rv_reactors.c b/kernel/trace/rv/rv_reactors.c
index 740603670dd1..7cc620a1be1a 100644
--- a/kernel/trace/rv/rv_reactors.c
+++ b/kernel/trace/rv/rv_reactors.c
@@ -138,10 +138,10 @@ static const struct file_operations available_reactors_ops = {
*/
static int monitor_reactor_show(struct seq_file *m, void *p)
{
- struct rv_monitor_def *mdef = m->private;
+ struct rv_monitor *mon = m->private;
struct rv_reactor_def *rdef = p;
- if (mdef->rdef == rdef)
+ if (mon->rdef == rdef)
seq_printf(m, "[%s]\n", rdef->reactor->name);
else
seq_printf(m, "%s\n", rdef->reactor->name);
@@ -158,41 +158,41 @@ static const struct seq_operations monitor_reactors_seq_ops = {
.show = monitor_reactor_show
};
-static void monitor_swap_reactors_single(struct rv_monitor_def *mdef,
+static void monitor_swap_reactors_single(struct rv_monitor *mon,
struct rv_reactor_def *rdef,
bool reacting, bool nested)
{
bool monitor_enabled;
/* nothing to do */
- if (mdef->rdef == rdef)
+ if (mon->rdef == rdef)
return;
- monitor_enabled = mdef->monitor->enabled;
+ monitor_enabled = mon->enabled;
if (monitor_enabled)
- rv_disable_monitor(mdef);
+ rv_disable_monitor(mon);
/* swap reactor's usage */
- mdef->rdef->counter--;
+ mon->rdef->counter--;
rdef->counter++;
- mdef->rdef = rdef;
- mdef->reacting = reacting;
- mdef->monitor->react = rdef->reactor->react;
+ mon->rdef = rdef;
+ mon->reacting = reacting;
+ mon->react = rdef->reactor->react;
/* enable only once if iterating through a container */
if (monitor_enabled && !nested)
- rv_enable_monitor(mdef);
+ rv_enable_monitor(mon);
}
-static void monitor_swap_reactors(struct rv_monitor_def *mdef,
+static void monitor_swap_reactors(struct rv_monitor *mon,
struct rv_reactor_def *rdef, bool reacting)
{
- struct rv_monitor_def *p = mdef;
+ struct rv_monitor *p = mon;
- if (rv_is_container_monitor(mdef))
+ if (rv_is_container_monitor(mon))
list_for_each_entry_continue(p, &rv_monitors_list, list) {
- if (p->parent != mdef->monitor)
+ if (p->parent != mon)
break;
monitor_swap_reactors_single(p, rdef, reacting, true);
}
@@ -202,7 +202,7 @@ static void monitor_swap_reactors(struct rv_monitor_def *mdef,
* All nested monitors are enabled also if they were off, we may refine
* this logic in the future.
*/
- monitor_swap_reactors_single(mdef, rdef, reacting, false);
+ monitor_swap_reactors_single(mon, rdef, reacting, false);
}
static ssize_t
@@ -210,7 +210,7 @@ monitor_reactors_write(struct file *file, const char __user *user_buf,
size_t count, loff_t *ppos)
{
char buff[MAX_RV_REACTOR_NAME_SIZE + 2];
- struct rv_monitor_def *mdef;
+ struct rv_monitor *mon;
struct rv_reactor_def *rdef;
struct seq_file *seq_f;
int retval = -EINVAL;
@@ -237,7 +237,7 @@ monitor_reactors_write(struct file *file, const char __user *user_buf,
* See monitor_reactors_open()
*/
seq_f = file->private_data;
- mdef = seq_f->private;
+ mon = seq_f->private;
mutex_lock(&rv_interface_lock);
@@ -252,7 +252,7 @@ monitor_reactors_write(struct file *file, const char __user *user_buf,
else
enable = true;
- monitor_swap_reactors(mdef, rdef, enable);
+ monitor_swap_reactors(mon, rdef, enable);
retval = count;
break;
@@ -268,7 +268,7 @@ monitor_reactors_write(struct file *file, const char __user *user_buf,
*/
static int monitor_reactors_open(struct inode *inode, struct file *file)
{
- struct rv_monitor_def *mdef = inode->i_private;
+ struct rv_monitor *mon = inode->i_private;
struct seq_file *seq_f;
int ret;
@@ -284,7 +284,7 @@ static int monitor_reactors_open(struct inode *inode, struct file *file)
/*
* Copy the create file "private" data to the seq_file private data.
*/
- seq_f->private = mdef;
+ seq_f->private = mon;
return 0;
};
@@ -454,37 +454,37 @@ static const struct file_operations reacting_on_fops = {
/**
* reactor_populate_monitor - creates per monitor reactors file
- * @mdef: monitor's definition.
+ * @mon: The monitor.
*
* Returns 0 if successful, error otherwise.
*/
-int reactor_populate_monitor(struct rv_monitor_def *mdef)
+int reactor_populate_monitor(struct rv_monitor *mon)
{
struct dentry *tmp;
- tmp = rv_create_file("reactors", RV_MODE_WRITE, mdef->root_d, mdef, &monitor_reactors_ops);
+ tmp = rv_create_file("reactors", RV_MODE_WRITE, mon->root_d, mon, &monitor_reactors_ops);
if (!tmp)
return -ENOMEM;
/*
* Configure as the rv_nop reactor.
*/
- mdef->rdef = get_reactor_rdef_by_name("nop");
- mdef->rdef->counter++;
- mdef->reacting = false;
+ mon->rdef = get_reactor_rdef_by_name("nop");
+ mon->rdef->counter++;
+ mon->reacting = false;
return 0;
}
/**
* reactor_cleanup_monitor - cleanup a monitor reference
- * @mdef: monitor's definition.
+ * @mon: the monitor.
*/
-void reactor_cleanup_monitor(struct rv_monitor_def *mdef)
+void reactor_cleanup_monitor(struct rv_monitor *mon)
{
lockdep_assert_held(&rv_interface_lock);
- mdef->rdef->counter--;
- WARN_ON_ONCE(mdef->rdef->counter < 0);
+ mon->rdef->counter--;
+ WARN_ON_ONCE(mon->rdef->counter < 0);
}
/*
--
2.39.5
^ permalink raw reply related [flat|nested] 7+ messages in thread* [PATCH v2 3/5] rv: Merge struct rv_reactor_def into struct rv_reactor
2025-07-23 6:44 [PATCH v2 0/5] rv: Clean up & simplify Nam Cao
2025-07-23 6:44 ` [PATCH v2 1/5] rv: Remove unused field in struct rv_monitor_def Nam Cao
2025-07-23 6:44 ` [PATCH v2 2/5] rv: Merge struct rv_monitor_def into struct rv_monitor Nam Cao
@ 2025-07-23 6:44 ` Nam Cao
2025-07-23 6:44 ` [PATCH v2 4/5] rv: Remove rv_reactor's reference counter Nam Cao
2025-07-23 6:44 ` [PATCH v2 5/5] rv: Remove struct rv_monitor::reacting Nam Cao
4 siblings, 0 replies; 7+ messages in thread
From: Nam Cao @ 2025-07-23 6:44 UTC (permalink / raw)
To: Steven Rostedt, Masami Hiramatsu, Mathieu Desnoyers,
Gabriele Monaco, linux-trace-kernel, linux-kernel
Cc: Nam Cao
Each struct rv_reactor has a unique struct rv_reactor_def associated with
it. struct rv_reactor is statically allocated, while struct rv_reactor_def
is dynamically allocated.
This makes the code more complicated than it should be:
- Lookup is required to get the associated rv_reactor_def from rv_reactor
- Dynamic memory allocation is required for rv_reactor_def. This is
harder to get right compared to static memory. For instance, there is
an existing mistake: rv_unregister_reactor() does not free the memory
allocated by rv_register_reactor(). This is fortunately not a real
memory leak problem as rv_unregister_reactor() is never called.
Simplify and merge rv_reactor_def into rv_reactor.
Reviewed-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Nam Cao <namcao@linutronix.de>
---
include/linux/rv.h | 5 +-
kernel/trace/rv/rv.h | 9 ----
kernel/trace/rv/rv_reactors.c | 92 +++++++++++++++--------------------
3 files changed, 43 insertions(+), 63 deletions(-)
diff --git a/include/linux/rv.h b/include/linux/rv.h
index dba53aecdfab..c22c9b8c1567 100644
--- a/include/linux/rv.h
+++ b/include/linux/rv.h
@@ -90,6 +90,9 @@ struct rv_reactor {
const char *name;
const char *description;
__printf(1, 2) void (*react)(const char *msg, ...);
+ struct list_head list;
+ /* protected by the monitor interface lock */
+ int counter;
};
#endif
@@ -101,7 +104,7 @@ struct rv_monitor {
void (*disable)(void);
void (*reset)(void);
#ifdef CONFIG_RV_REACTORS
- struct rv_reactor_def *rdef;
+ struct rv_reactor *reactor;
__printf(1, 2) void (*react)(const char *msg, ...);
bool reacting;
#endif
diff --git a/kernel/trace/rv/rv.h b/kernel/trace/rv/rv.h
index f039ec1c9156..8c38f9dd41bc 100644
--- a/kernel/trace/rv/rv.h
+++ b/kernel/trace/rv/rv.h
@@ -23,15 +23,6 @@ struct rv_interface {
extern struct mutex rv_interface_lock;
extern struct list_head rv_monitors_list;
-#ifdef CONFIG_RV_REACTORS
-struct rv_reactor_def {
- struct list_head list;
- struct rv_reactor *reactor;
- /* protected by the monitor interface lock */
- int counter;
-};
-#endif
-
struct dentry *get_monitors_root(void);
int rv_disable_monitor(struct rv_monitor *mon);
int rv_enable_monitor(struct rv_monitor *mon);
diff --git a/kernel/trace/rv/rv_reactors.c b/kernel/trace/rv/rv_reactors.c
index 7cc620a1be1a..2c7909e6d0e7 100644
--- a/kernel/trace/rv/rv_reactors.c
+++ b/kernel/trace/rv/rv_reactors.c
@@ -70,12 +70,12 @@
*/
static LIST_HEAD(rv_reactors_list);
-static struct rv_reactor_def *get_reactor_rdef_by_name(char *name)
+static struct rv_reactor *get_reactor_rdef_by_name(char *name)
{
- struct rv_reactor_def *r;
+ struct rv_reactor *r;
list_for_each_entry(r, &rv_reactors_list, list) {
- if (strcmp(name, r->reactor->name) == 0)
+ if (strcmp(name, r->name) == 0)
return r;
}
return NULL;
@@ -86,9 +86,9 @@ static struct rv_reactor_def *get_reactor_rdef_by_name(char *name)
*/
static int reactors_show(struct seq_file *m, void *p)
{
- struct rv_reactor_def *rea_def = p;
+ struct rv_reactor *reactor = p;
- seq_printf(m, "%s\n", rea_def->reactor->name);
+ seq_printf(m, "%s\n", reactor->name);
return 0;
}
@@ -139,12 +139,12 @@ static const struct file_operations available_reactors_ops = {
static int monitor_reactor_show(struct seq_file *m, void *p)
{
struct rv_monitor *mon = m->private;
- struct rv_reactor_def *rdef = p;
+ struct rv_reactor *reactor = p;
- if (mon->rdef == rdef)
- seq_printf(m, "[%s]\n", rdef->reactor->name);
+ if (mon->reactor == reactor)
+ seq_printf(m, "[%s]\n", reactor->name);
else
- seq_printf(m, "%s\n", rdef->reactor->name);
+ seq_printf(m, "%s\n", reactor->name);
return 0;
}
@@ -159,13 +159,13 @@ static const struct seq_operations monitor_reactors_seq_ops = {
};
static void monitor_swap_reactors_single(struct rv_monitor *mon,
- struct rv_reactor_def *rdef,
+ struct rv_reactor *reactor,
bool reacting, bool nested)
{
bool monitor_enabled;
/* nothing to do */
- if (mon->rdef == rdef)
+ if (mon->reactor == reactor)
return;
monitor_enabled = mon->enabled;
@@ -173,12 +173,12 @@ static void monitor_swap_reactors_single(struct rv_monitor *mon,
rv_disable_monitor(mon);
/* swap reactor's usage */
- mon->rdef->counter--;
- rdef->counter++;
+ mon->reactor->counter--;
+ reactor->counter++;
- mon->rdef = rdef;
+ mon->reactor = reactor;
mon->reacting = reacting;
- mon->react = rdef->reactor->react;
+ mon->react = reactor->react;
/* enable only once if iterating through a container */
if (monitor_enabled && !nested)
@@ -186,7 +186,7 @@ static void monitor_swap_reactors_single(struct rv_monitor *mon,
}
static void monitor_swap_reactors(struct rv_monitor *mon,
- struct rv_reactor_def *rdef, bool reacting)
+ struct rv_reactor *reactor, bool reacting)
{
struct rv_monitor *p = mon;
@@ -194,7 +194,7 @@ static void monitor_swap_reactors(struct rv_monitor *mon,
list_for_each_entry_continue(p, &rv_monitors_list, list) {
if (p->parent != mon)
break;
- monitor_swap_reactors_single(p, rdef, reacting, true);
+ monitor_swap_reactors_single(p, reactor, reacting, true);
}
/*
* This call enables and disables the monitor if they were active.
@@ -202,7 +202,7 @@ static void monitor_swap_reactors(struct rv_monitor *mon,
* All nested monitors are enabled also if they were off, we may refine
* this logic in the future.
*/
- monitor_swap_reactors_single(mon, rdef, reacting, false);
+ monitor_swap_reactors_single(mon, reactor, reacting, false);
}
static ssize_t
@@ -211,7 +211,7 @@ monitor_reactors_write(struct file *file, const char __user *user_buf,
{
char buff[MAX_RV_REACTOR_NAME_SIZE + 2];
struct rv_monitor *mon;
- struct rv_reactor_def *rdef;
+ struct rv_reactor *reactor;
struct seq_file *seq_f;
int retval = -EINVAL;
bool enable;
@@ -243,16 +243,16 @@ monitor_reactors_write(struct file *file, const char __user *user_buf,
retval = -EINVAL;
- list_for_each_entry(rdef, &rv_reactors_list, list) {
- if (strcmp(ptr, rdef->reactor->name) != 0)
+ list_for_each_entry(reactor, &rv_reactors_list, list) {
+ if (strcmp(ptr, reactor->name) != 0)
continue;
- if (rdef == get_reactor_rdef_by_name("nop"))
+ if (strcmp(reactor->name, "nop"))
enable = false;
else
enable = true;
- monitor_swap_reactors(mon, rdef, enable);
+ monitor_swap_reactors(mon, reactor, enable);
retval = count;
break;
@@ -299,23 +299,16 @@ static const struct file_operations monitor_reactors_ops = {
static int __rv_register_reactor(struct rv_reactor *reactor)
{
- struct rv_reactor_def *r;
+ struct rv_reactor *r;
list_for_each_entry(r, &rv_reactors_list, list) {
- if (strcmp(reactor->name, r->reactor->name) == 0) {
+ if (strcmp(reactor->name, r->name) == 0) {
pr_info("Reactor %s is already registered\n", reactor->name);
return -EINVAL;
}
}
- r = kzalloc(sizeof(struct rv_reactor_def), GFP_KERNEL);
- if (!r)
- return -ENOMEM;
-
- r->reactor = reactor;
- r->counter = 0;
-
- list_add_tail(&r->list, &rv_reactors_list);
+ list_add_tail(&reactor->list, &rv_reactors_list);
return 0;
}
@@ -350,26 +343,19 @@ int rv_register_reactor(struct rv_reactor *reactor)
*/
int rv_unregister_reactor(struct rv_reactor *reactor)
{
- struct rv_reactor_def *ptr, *next;
int ret = 0;
mutex_lock(&rv_interface_lock);
- list_for_each_entry_safe(ptr, next, &rv_reactors_list, list) {
- if (strcmp(reactor->name, ptr->reactor->name) == 0) {
-
- if (!ptr->counter) {
- list_del(&ptr->list);
- } else {
- printk(KERN_WARNING
- "rv: the rv_reactor %s is in use by %d monitor(s)\n",
- ptr->reactor->name, ptr->counter);
- printk(KERN_WARNING "rv: the rv_reactor %s cannot be removed\n",
- ptr->reactor->name);
- ret = -EBUSY;
- break;
- }
- }
+ if (!reactor->counter) {
+ list_del(&reactor->list);
+ } else {
+ printk(KERN_WARNING
+ "rv: the rv_reactor %s is in use by %d monitor(s)\n",
+ reactor->name, reactor->counter);
+ printk(KERN_WARNING "rv: the rv_reactor %s cannot be removed\n",
+ reactor->name);
+ ret = -EBUSY;
}
mutex_unlock(&rv_interface_lock);
@@ -469,8 +455,8 @@ int reactor_populate_monitor(struct rv_monitor *mon)
/*
* Configure as the rv_nop reactor.
*/
- mon->rdef = get_reactor_rdef_by_name("nop");
- mon->rdef->counter++;
+ mon->reactor = get_reactor_rdef_by_name("nop");
+ mon->reactor->counter++;
mon->reacting = false;
return 0;
@@ -483,8 +469,8 @@ int reactor_populate_monitor(struct rv_monitor *mon)
void reactor_cleanup_monitor(struct rv_monitor *mon)
{
lockdep_assert_held(&rv_interface_lock);
- mon->rdef->counter--;
- WARN_ON_ONCE(mon->rdef->counter < 0);
+ mon->reactor->counter--;
+ WARN_ON_ONCE(mon->reactor->counter < 0);
}
/*
--
2.39.5
^ permalink raw reply related [flat|nested] 7+ messages in thread