* [PATCH v3 0/6] tracing: export event trace and trace_marker
@ 2020-09-03 0:17 ` Tingwei Zhang
0 siblings, 0 replies; 25+ messages in thread
From: Tingwei Zhang @ 2020-09-03 0:17 UTC (permalink / raw)
To: Steven Rostedt, Ingo Molnar, Alexander Shishkin, Maxime Coquelin,
Alexandre Torgue
Cc: Tingwei Zhang, Mathieu Poirier, Suzuki K Poulose, tsoni,
Sai Prakash Ranjan, Mao Jinlong, linux-kernel, linux-stm32,
linux-arm-kernel
Ftrace has ability to export trace packets to other destination.
Currently, only function trace can be exported. This series extends the
support to event trace and trace_maker. STM is one possible destination to
export ftrace. Use separate channel for each CPU to avoid mixing up packets
from different CPUs together.
Change from v2:
Change flag definition to BIT(). (Steven)
Add comment in stm_ftrace_write() to clarify it's safe to use
smp_processor_id() here since preempt is disabled. (Steven)
Change from v1:
All changes are suggested by Steven Rostedt.
User separate flag to control function trace, event trace and trace mark.
Allocate channels according to num_possible_cpu() dynamically.
Move ftrace_exports routines up so all ftrace can use them.
Tingwei Zhang (6):
stm class: ftrace: change dependency to TRACING
tracing: add flag to control different traces
tracing: add trace_export support for event trace
tracing: add trace_export support for trace_marker
stm class: ftrace: enable supported trace export flag
stm class: ftrace: use different channel accroding to CPU
drivers/hwtracing/stm/Kconfig | 2 +-
drivers/hwtracing/stm/ftrace.c | 7 +-
include/linux/trace.h | 7 +
kernel/trace/trace.c | 270 ++++++++++++++++++---------------
4 files changed, 159 insertions(+), 127 deletions(-)
--
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project
^ permalink raw reply [flat|nested] 25+ messages in thread
* [PATCH v3 1/6] stm class: ftrace: change dependency to TRACING
2020-09-03 0:17 ` Tingwei Zhang
@ 2020-09-03 0:17 ` Tingwei Zhang
-1 siblings, 0 replies; 25+ messages in thread
From: Tingwei Zhang @ 2020-09-03 0:17 UTC (permalink / raw)
To: Steven Rostedt, Ingo Molnar, Alexander Shishkin, Maxime Coquelin,
Alexandre Torgue
Cc: tsoni, Sai Prakash Ranjan, Mathieu Poirier, Suzuki K Poulose,
Mao Jinlong, linux-kernel, Tingwei Zhang, linux-stm32,
linux-arm-kernel
We will support copying event trace to STM. Change
STM_SOURCE_FTRACE to depend on TRACING since we will
support multiple tracers.
Signed-off-by: Tingwei Zhang <tingwei@codeaurora.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
drivers/hwtracing/stm/Kconfig | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/hwtracing/stm/Kconfig b/drivers/hwtracing/stm/Kconfig
index d0e92a8a045c..aad594fe79cc 100644
--- a/drivers/hwtracing/stm/Kconfig
+++ b/drivers/hwtracing/stm/Kconfig
@@ -71,7 +71,7 @@ config STM_SOURCE_HEARTBEAT
config STM_SOURCE_FTRACE
tristate "Copy the output from kernel Ftrace to STM engine"
- depends on FUNCTION_TRACER
+ depends on TRACING
help
This option can be used to copy the output from kernel Ftrace
to STM engine. Enabling this option will introduce a slight
--
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply related [flat|nested] 25+ messages in thread
* [PATCH v3 1/6] stm class: ftrace: change dependency to TRACING
@ 2020-09-03 0:17 ` Tingwei Zhang
0 siblings, 0 replies; 25+ messages in thread
From: Tingwei Zhang @ 2020-09-03 0:17 UTC (permalink / raw)
To: Steven Rostedt, Ingo Molnar, Alexander Shishkin, Maxime Coquelin,
Alexandre Torgue
Cc: Tingwei Zhang, Mathieu Poirier, Suzuki K Poulose, tsoni,
Sai Prakash Ranjan, Mao Jinlong, linux-kernel, linux-stm32,
linux-arm-kernel
We will support copying event trace to STM. Change
STM_SOURCE_FTRACE to depend on TRACING since we will
support multiple tracers.
Signed-off-by: Tingwei Zhang <tingwei@codeaurora.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
drivers/hwtracing/stm/Kconfig | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/hwtracing/stm/Kconfig b/drivers/hwtracing/stm/Kconfig
index d0e92a8a045c..aad594fe79cc 100644
--- a/drivers/hwtracing/stm/Kconfig
+++ b/drivers/hwtracing/stm/Kconfig
@@ -71,7 +71,7 @@ config STM_SOURCE_HEARTBEAT
config STM_SOURCE_FTRACE
tristate "Copy the output from kernel Ftrace to STM engine"
- depends on FUNCTION_TRACER
+ depends on TRACING
help
This option can be used to copy the output from kernel Ftrace
to STM engine. Enabling this option will introduce a slight
--
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project
^ permalink raw reply related [flat|nested] 25+ messages in thread
* [PATCH v3 2/6] tracing: add flag to control different traces
2020-09-03 0:17 ` Tingwei Zhang
@ 2020-09-03 0:17 ` Tingwei Zhang
-1 siblings, 0 replies; 25+ messages in thread
From: Tingwei Zhang @ 2020-09-03 0:17 UTC (permalink / raw)
To: Steven Rostedt, Ingo Molnar, Alexander Shishkin, Maxime Coquelin,
Alexandre Torgue
Cc: tsoni, Sai Prakash Ranjan, Mathieu Poirier, Suzuki K Poulose,
Mao Jinlong, linux-kernel, Tingwei Zhang, linux-stm32,
linux-arm-kernel
More traces like event trace or trace marker will be supported.
Add flag for difference traces, so that they can be controlled
separately. Move current function trace to it's own flag
instead of global ftrace enable flag.
Signed-off-by: Tingwei Zhang <tingwei@codeaurora.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
include/linux/trace.h | 5 +++++
kernel/trace/trace.c | 36 +++++++++++++++++++-----------------
2 files changed, 24 insertions(+), 17 deletions(-)
diff --git a/include/linux/trace.h b/include/linux/trace.h
index 7fd86d3c691f..bc93063dda39 100644
--- a/include/linux/trace.h
+++ b/include/linux/trace.h
@@ -3,6 +3,9 @@
#define _LINUX_TRACE_H
#ifdef CONFIG_TRACING
+
+#define TRACE_EXPORT_FUNCTION BIT(0)
+
/*
* The trace export - an export of Ftrace output. The trace_export
* can process traces and export them to a registered destination as
@@ -15,10 +18,12 @@
* next - pointer to the next trace_export
* write - copy traces which have been delt with ->commit() to
* the destination
+ * flags - which ftrace to be exported
*/
struct trace_export {
struct trace_export __rcu *next;
void (*write)(struct trace_export *, const void *, unsigned int);
+ int flags;
};
int register_ftrace_export(struct trace_export *export);
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index bb62269724d5..8f1e66831e9e 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -2747,33 +2747,37 @@ trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer,
static void
trace_process_export(struct trace_export *export,
- struct ring_buffer_event *event)
+ struct ring_buffer_event *event, int flag)
{
struct trace_entry *entry;
unsigned int size = 0;
- entry = ring_buffer_event_data(event);
- size = ring_buffer_event_length(event);
- export->write(export, entry, size);
+ if (export->flags & flag) {
+ entry = ring_buffer_event_data(event);
+ size = ring_buffer_event_length(event);
+ export->write(export, entry, size);
+ }
}
static DEFINE_MUTEX(ftrace_export_lock);
static struct trace_export __rcu *ftrace_exports_list __read_mostly;
-static DEFINE_STATIC_KEY_FALSE(ftrace_exports_enabled);
+static DEFINE_STATIC_KEY_FALSE(trace_function_exports_enabled);
-static inline void ftrace_exports_enable(void)
+static inline void ftrace_exports_enable(struct trace_export *export)
{
- static_branch_enable(&ftrace_exports_enabled);
+ if (export->flags & TRACE_EXPORT_FUNCTION)
+ static_branch_inc(&trace_function_exports_enabled);
}
-static inline void ftrace_exports_disable(void)
+static inline void ftrace_exports_disable(struct trace_export *export)
{
- static_branch_disable(&ftrace_exports_enabled);
+ if (export->flags & TRACE_EXPORT_FUNCTION)
+ static_branch_dec(&trace_function_exports_enabled);
}
-static void ftrace_exports(struct ring_buffer_event *event)
+static void ftrace_exports(struct ring_buffer_event *event, int flag)
{
struct trace_export *export;
@@ -2781,7 +2785,7 @@ static void ftrace_exports(struct ring_buffer_event *event)
export = rcu_dereference_raw_check(ftrace_exports_list);
while (export) {
- trace_process_export(export, event);
+ trace_process_export(export, event, flag);
export = rcu_dereference_raw_check(export->next);
}
@@ -2821,8 +2825,7 @@ rm_trace_export(struct trace_export **list, struct trace_export *export)
static inline void
add_ftrace_export(struct trace_export **list, struct trace_export *export)
{
- if (*list == NULL)
- ftrace_exports_enable();
+ ftrace_exports_enable(export);
add_trace_export(list, export);
}
@@ -2833,8 +2836,7 @@ rm_ftrace_export(struct trace_export **list, struct trace_export *export)
int ret;
ret = rm_trace_export(list, export);
- if (*list == NULL)
- ftrace_exports_disable();
+ ftrace_exports_disable(export);
return ret;
}
@@ -2887,8 +2889,8 @@ trace_function(struct trace_array *tr,
entry->parent_ip = parent_ip;
if (!call_filter_check_discard(call, entry, buffer, event)) {
- if (static_branch_unlikely(&ftrace_exports_enabled))
- ftrace_exports(event);
+ if (static_branch_unlikely(&trace_function_exports_enabled))
+ ftrace_exports(event, TRACE_EXPORT_FUNCTION);
__buffer_unlock_commit(buffer, event);
}
}
--
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply related [flat|nested] 25+ messages in thread* [PATCH v3 2/6] tracing: add flag to control different traces
@ 2020-09-03 0:17 ` Tingwei Zhang
0 siblings, 0 replies; 25+ messages in thread
From: Tingwei Zhang @ 2020-09-03 0:17 UTC (permalink / raw)
To: Steven Rostedt, Ingo Molnar, Alexander Shishkin, Maxime Coquelin,
Alexandre Torgue
Cc: Tingwei Zhang, Mathieu Poirier, Suzuki K Poulose, tsoni,
Sai Prakash Ranjan, Mao Jinlong, linux-kernel, linux-stm32,
linux-arm-kernel
More traces like event trace or trace marker will be supported.
Add flag for difference traces, so that they can be controlled
separately. Move current function trace to it's own flag
instead of global ftrace enable flag.
Signed-off-by: Tingwei Zhang <tingwei@codeaurora.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
include/linux/trace.h | 5 +++++
kernel/trace/trace.c | 36 +++++++++++++++++++-----------------
2 files changed, 24 insertions(+), 17 deletions(-)
diff --git a/include/linux/trace.h b/include/linux/trace.h
index 7fd86d3c691f..bc93063dda39 100644
--- a/include/linux/trace.h
+++ b/include/linux/trace.h
@@ -3,6 +3,9 @@
#define _LINUX_TRACE_H
#ifdef CONFIG_TRACING
+
+#define TRACE_EXPORT_FUNCTION BIT(0)
+
/*
* The trace export - an export of Ftrace output. The trace_export
* can process traces and export them to a registered destination as
@@ -15,10 +18,12 @@
* next - pointer to the next trace_export
* write - copy traces which have been delt with ->commit() to
* the destination
+ * flags - which ftrace to be exported
*/
struct trace_export {
struct trace_export __rcu *next;
void (*write)(struct trace_export *, const void *, unsigned int);
+ int flags;
};
int register_ftrace_export(struct trace_export *export);
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index bb62269724d5..8f1e66831e9e 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -2747,33 +2747,37 @@ trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer,
static void
trace_process_export(struct trace_export *export,
- struct ring_buffer_event *event)
+ struct ring_buffer_event *event, int flag)
{
struct trace_entry *entry;
unsigned int size = 0;
- entry = ring_buffer_event_data(event);
- size = ring_buffer_event_length(event);
- export->write(export, entry, size);
+ if (export->flags & flag) {
+ entry = ring_buffer_event_data(event);
+ size = ring_buffer_event_length(event);
+ export->write(export, entry, size);
+ }
}
static DEFINE_MUTEX(ftrace_export_lock);
static struct trace_export __rcu *ftrace_exports_list __read_mostly;
-static DEFINE_STATIC_KEY_FALSE(ftrace_exports_enabled);
+static DEFINE_STATIC_KEY_FALSE(trace_function_exports_enabled);
-static inline void ftrace_exports_enable(void)
+static inline void ftrace_exports_enable(struct trace_export *export)
{
- static_branch_enable(&ftrace_exports_enabled);
+ if (export->flags & TRACE_EXPORT_FUNCTION)
+ static_branch_inc(&trace_function_exports_enabled);
}
-static inline void ftrace_exports_disable(void)
+static inline void ftrace_exports_disable(struct trace_export *export)
{
- static_branch_disable(&ftrace_exports_enabled);
+ if (export->flags & TRACE_EXPORT_FUNCTION)
+ static_branch_dec(&trace_function_exports_enabled);
}
-static void ftrace_exports(struct ring_buffer_event *event)
+static void ftrace_exports(struct ring_buffer_event *event, int flag)
{
struct trace_export *export;
@@ -2781,7 +2785,7 @@ static void ftrace_exports(struct ring_buffer_event *event)
export = rcu_dereference_raw_check(ftrace_exports_list);
while (export) {
- trace_process_export(export, event);
+ trace_process_export(export, event, flag);
export = rcu_dereference_raw_check(export->next);
}
@@ -2821,8 +2825,7 @@ rm_trace_export(struct trace_export **list, struct trace_export *export)
static inline void
add_ftrace_export(struct trace_export **list, struct trace_export *export)
{
- if (*list == NULL)
- ftrace_exports_enable();
+ ftrace_exports_enable(export);
add_trace_export(list, export);
}
@@ -2833,8 +2836,7 @@ rm_ftrace_export(struct trace_export **list, struct trace_export *export)
int ret;
ret = rm_trace_export(list, export);
- if (*list == NULL)
- ftrace_exports_disable();
+ ftrace_exports_disable(export);
return ret;
}
@@ -2887,8 +2889,8 @@ trace_function(struct trace_array *tr,
entry->parent_ip = parent_ip;
if (!call_filter_check_discard(call, entry, buffer, event)) {
- if (static_branch_unlikely(&ftrace_exports_enabled))
- ftrace_exports(event);
+ if (static_branch_unlikely(&trace_function_exports_enabled))
+ ftrace_exports(event, TRACE_EXPORT_FUNCTION);
__buffer_unlock_commit(buffer, event);
}
}
--
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project
^ permalink raw reply related [flat|nested] 25+ messages in thread
* [PATCH v3 3/6] tracing: add trace_export support for event trace
2020-09-03 0:17 ` Tingwei Zhang
@ 2020-09-03 0:17 ` Tingwei Zhang
-1 siblings, 0 replies; 25+ messages in thread
From: Tingwei Zhang @ 2020-09-03 0:17 UTC (permalink / raw)
To: Steven Rostedt, Ingo Molnar, Alexander Shishkin, Maxime Coquelin,
Alexandre Torgue
Cc: tsoni, Sai Prakash Ranjan, Mathieu Poirier, Suzuki K Poulose,
Mao Jinlong, linux-kernel, Tingwei Zhang, linux-stm32,
linux-arm-kernel
Only function traces can be exported to other destinations currently.
This patch exports event trace as well. Move trace export related
function to the beginning of file so other trace can call
trace_process_export() to export.
Signed-off-by: Tingwei Zhang <tingwei@codeaurora.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
include/linux/trace.h | 1 +
kernel/trace/trace.c | 259 ++++++++++++++++++++++--------------------
2 files changed, 135 insertions(+), 125 deletions(-)
diff --git a/include/linux/trace.h b/include/linux/trace.h
index bc93063dda39..5a01eeffb254 100644
--- a/include/linux/trace.h
+++ b/include/linux/trace.h
@@ -5,6 +5,7 @@
#ifdef CONFIG_TRACING
#define TRACE_EXPORT_FUNCTION BIT(0)
+#define TRACE_EXPORT_EVENT BIT(1)
/*
* The trace export - an export of Ftrace output. The trace_export
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 8f1e66831e9e..2f9302a8b322 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -251,6 +251,138 @@ unsigned long long ns2usecs(u64 nsec)
return nsec;
}
+static void
+trace_process_export(struct trace_export *export,
+ struct ring_buffer_event *event, int flag)
+{
+ struct trace_entry *entry;
+ unsigned int size = 0;
+
+ if (export->flags & flag) {
+ entry = ring_buffer_event_data(event);
+ size = ring_buffer_event_length(event);
+ export->write(export, entry, size);
+ }
+}
+
+static DEFINE_MUTEX(ftrace_export_lock);
+
+static struct trace_export __rcu *ftrace_exports_list __read_mostly;
+
+static DEFINE_STATIC_KEY_FALSE(trace_function_exports_enabled);
+static DEFINE_STATIC_KEY_FALSE(trace_event_exports_enabled);
+
+static inline void ftrace_exports_enable(struct trace_export *export)
+{
+ if (export->flags & TRACE_EXPORT_FUNCTION)
+ static_branch_inc(&trace_function_exports_enabled);
+
+ if (export->flags & TRACE_EXPORT_EVENT)
+ static_branch_inc(&trace_event_exports_enabled);
+}
+
+static inline void ftrace_exports_disable(struct trace_export *export)
+{
+ if (export->flags & TRACE_EXPORT_FUNCTION)
+ static_branch_dec(&trace_function_exports_enabled);
+
+ if (export->flags & TRACE_EXPORT_EVENT)
+ static_branch_dec(&trace_event_exports_enabled);
+}
+
+static void ftrace_exports(struct ring_buffer_event *event, int flag)
+{
+ struct trace_export *export;
+
+ preempt_disable_notrace();
+
+ export = rcu_dereference_raw_check(ftrace_exports_list);
+ while (export) {
+ trace_process_export(export, event, flag);
+ export = rcu_dereference_raw_check(export->next);
+ }
+
+ preempt_enable_notrace();
+}
+
+static inline void
+add_trace_export(struct trace_export **list, struct trace_export *export)
+{
+ rcu_assign_pointer(export->next, *list);
+ /*
+ * We are entering export into the list but another
+ * CPU might be walking that list. We need to make sure
+ * the export->next pointer is valid before another CPU sees
+ * the export pointer included into the list.
+ */
+ rcu_assign_pointer(*list, export);
+}
+
+static inline int
+rm_trace_export(struct trace_export **list, struct trace_export *export)
+{
+ struct trace_export **p;
+
+ for (p = list; *p != NULL; p = &(*p)->next)
+ if (*p == export)
+ break;
+
+ if (*p != export)
+ return -1;
+
+ rcu_assign_pointer(*p, (*p)->next);
+
+ return 0;
+}
+
+static inline void
+add_ftrace_export(struct trace_export **list, struct trace_export *export)
+{
+ ftrace_exports_enable(export);
+
+ add_trace_export(list, export);
+}
+
+static inline int
+rm_ftrace_export(struct trace_export **list, struct trace_export *export)
+{
+ int ret;
+
+ ret = rm_trace_export(list, export);
+ ftrace_exports_disable(export);
+
+ return ret;
+}
+
+int register_ftrace_export(struct trace_export *export)
+{
+ if (WARN_ON_ONCE(!export->write))
+ return -1;
+
+ mutex_lock(&ftrace_export_lock);
+
+ add_ftrace_export(&ftrace_exports_list, export);
+
+ mutex_unlock(&ftrace_export_lock);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(register_ftrace_export);
+
+int unregister_ftrace_export(struct trace_export *export)
+{
+ int ret;
+
+ mutex_lock(&ftrace_export_lock);
+
+ ret = rm_ftrace_export(&ftrace_exports_list, export);
+
+ mutex_unlock(&ftrace_export_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(unregister_ftrace_export);
+
/* trace_flags holds trace_options default values */
#define TRACE_DEFAULT_FLAGS \
(FUNCTION_DEFAULT_FLAGS | \
@@ -2702,6 +2834,8 @@ void trace_event_buffer_commit(struct trace_event_buffer *fbuffer)
if (static_key_false(&tracepoint_printk_key.key))
output_printk(fbuffer);
+ if (static_branch_unlikely(&trace_event_exports_enabled))
+ ftrace_exports(fbuffer->event, TRACE_EXPORT_EVENT);
event_trigger_unlock_commit_regs(fbuffer->trace_file, fbuffer->buffer,
fbuffer->event, fbuffer->entry,
fbuffer->flags, fbuffer->pc, fbuffer->regs);
@@ -2745,131 +2879,6 @@ trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer,
__buffer_unlock_commit(buffer, event);
}
-static void
-trace_process_export(struct trace_export *export,
- struct ring_buffer_event *event, int flag)
-{
- struct trace_entry *entry;
- unsigned int size = 0;
-
- if (export->flags & flag) {
- entry = ring_buffer_event_data(event);
- size = ring_buffer_event_length(event);
- export->write(export, entry, size);
- }
-}
-
-static DEFINE_MUTEX(ftrace_export_lock);
-
-static struct trace_export __rcu *ftrace_exports_list __read_mostly;
-
-static DEFINE_STATIC_KEY_FALSE(trace_function_exports_enabled);
-
-static inline void ftrace_exports_enable(struct trace_export *export)
-{
- if (export->flags & TRACE_EXPORT_FUNCTION)
- static_branch_inc(&trace_function_exports_enabled);
-}
-
-static inline void ftrace_exports_disable(struct trace_export *export)
-{
- if (export->flags & TRACE_EXPORT_FUNCTION)
- static_branch_dec(&trace_function_exports_enabled);
-}
-
-static void ftrace_exports(struct ring_buffer_event *event, int flag)
-{
- struct trace_export *export;
-
- preempt_disable_notrace();
-
- export = rcu_dereference_raw_check(ftrace_exports_list);
- while (export) {
- trace_process_export(export, event, flag);
- export = rcu_dereference_raw_check(export->next);
- }
-
- preempt_enable_notrace();
-}
-
-static inline void
-add_trace_export(struct trace_export **list, struct trace_export *export)
-{
- rcu_assign_pointer(export->next, *list);
- /*
- * We are entering export into the list but another
- * CPU might be walking that list. We need to make sure
- * the export->next pointer is valid before another CPU sees
- * the export pointer included into the list.
- */
- rcu_assign_pointer(*list, export);
-}
-
-static inline int
-rm_trace_export(struct trace_export **list, struct trace_export *export)
-{
- struct trace_export **p;
-
- for (p = list; *p != NULL; p = &(*p)->next)
- if (*p == export)
- break;
-
- if (*p != export)
- return -1;
-
- rcu_assign_pointer(*p, (*p)->next);
-
- return 0;
-}
-
-static inline void
-add_ftrace_export(struct trace_export **list, struct trace_export *export)
-{
- ftrace_exports_enable(export);
-
- add_trace_export(list, export);
-}
-
-static inline int
-rm_ftrace_export(struct trace_export **list, struct trace_export *export)
-{
- int ret;
-
- ret = rm_trace_export(list, export);
- ftrace_exports_disable(export);
-
- return ret;
-}
-
-int register_ftrace_export(struct trace_export *export)
-{
- if (WARN_ON_ONCE(!export->write))
- return -1;
-
- mutex_lock(&ftrace_export_lock);
-
- add_ftrace_export(&ftrace_exports_list, export);
-
- mutex_unlock(&ftrace_export_lock);
-
- return 0;
-}
-EXPORT_SYMBOL_GPL(register_ftrace_export);
-
-int unregister_ftrace_export(struct trace_export *export)
-{
- int ret;
-
- mutex_lock(&ftrace_export_lock);
-
- ret = rm_ftrace_export(&ftrace_exports_list, export);
-
- mutex_unlock(&ftrace_export_lock);
-
- return ret;
-}
-EXPORT_SYMBOL_GPL(unregister_ftrace_export);
-
void
trace_function(struct trace_array *tr,
unsigned long ip, unsigned long parent_ip, unsigned long flags,
--
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project
_______________________________________________
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linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply related [flat|nested] 25+ messages in thread* [PATCH v3 3/6] tracing: add trace_export support for event trace
@ 2020-09-03 0:17 ` Tingwei Zhang
0 siblings, 0 replies; 25+ messages in thread
From: Tingwei Zhang @ 2020-09-03 0:17 UTC (permalink / raw)
To: Steven Rostedt, Ingo Molnar, Alexander Shishkin, Maxime Coquelin,
Alexandre Torgue
Cc: Tingwei Zhang, Mathieu Poirier, Suzuki K Poulose, tsoni,
Sai Prakash Ranjan, Mao Jinlong, linux-kernel, linux-stm32,
linux-arm-kernel
Only function traces can be exported to other destinations currently.
This patch exports event trace as well. Move trace export related
function to the beginning of file so other trace can call
trace_process_export() to export.
Signed-off-by: Tingwei Zhang <tingwei@codeaurora.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
include/linux/trace.h | 1 +
kernel/trace/trace.c | 259 ++++++++++++++++++++++--------------------
2 files changed, 135 insertions(+), 125 deletions(-)
diff --git a/include/linux/trace.h b/include/linux/trace.h
index bc93063dda39..5a01eeffb254 100644
--- a/include/linux/trace.h
+++ b/include/linux/trace.h
@@ -5,6 +5,7 @@
#ifdef CONFIG_TRACING
#define TRACE_EXPORT_FUNCTION BIT(0)
+#define TRACE_EXPORT_EVENT BIT(1)
/*
* The trace export - an export of Ftrace output. The trace_export
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 8f1e66831e9e..2f9302a8b322 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -251,6 +251,138 @@ unsigned long long ns2usecs(u64 nsec)
return nsec;
}
+static void
+trace_process_export(struct trace_export *export,
+ struct ring_buffer_event *event, int flag)
+{
+ struct trace_entry *entry;
+ unsigned int size = 0;
+
+ if (export->flags & flag) {
+ entry = ring_buffer_event_data(event);
+ size = ring_buffer_event_length(event);
+ export->write(export, entry, size);
+ }
+}
+
+static DEFINE_MUTEX(ftrace_export_lock);
+
+static struct trace_export __rcu *ftrace_exports_list __read_mostly;
+
+static DEFINE_STATIC_KEY_FALSE(trace_function_exports_enabled);
+static DEFINE_STATIC_KEY_FALSE(trace_event_exports_enabled);
+
+static inline void ftrace_exports_enable(struct trace_export *export)
+{
+ if (export->flags & TRACE_EXPORT_FUNCTION)
+ static_branch_inc(&trace_function_exports_enabled);
+
+ if (export->flags & TRACE_EXPORT_EVENT)
+ static_branch_inc(&trace_event_exports_enabled);
+}
+
+static inline void ftrace_exports_disable(struct trace_export *export)
+{
+ if (export->flags & TRACE_EXPORT_FUNCTION)
+ static_branch_dec(&trace_function_exports_enabled);
+
+ if (export->flags & TRACE_EXPORT_EVENT)
+ static_branch_dec(&trace_event_exports_enabled);
+}
+
+static void ftrace_exports(struct ring_buffer_event *event, int flag)
+{
+ struct trace_export *export;
+
+ preempt_disable_notrace();
+
+ export = rcu_dereference_raw_check(ftrace_exports_list);
+ while (export) {
+ trace_process_export(export, event, flag);
+ export = rcu_dereference_raw_check(export->next);
+ }
+
+ preempt_enable_notrace();
+}
+
+static inline void
+add_trace_export(struct trace_export **list, struct trace_export *export)
+{
+ rcu_assign_pointer(export->next, *list);
+ /*
+ * We are entering export into the list but another
+ * CPU might be walking that list. We need to make sure
+ * the export->next pointer is valid before another CPU sees
+ * the export pointer included into the list.
+ */
+ rcu_assign_pointer(*list, export);
+}
+
+static inline int
+rm_trace_export(struct trace_export **list, struct trace_export *export)
+{
+ struct trace_export **p;
+
+ for (p = list; *p != NULL; p = &(*p)->next)
+ if (*p == export)
+ break;
+
+ if (*p != export)
+ return -1;
+
+ rcu_assign_pointer(*p, (*p)->next);
+
+ return 0;
+}
+
+static inline void
+add_ftrace_export(struct trace_export **list, struct trace_export *export)
+{
+ ftrace_exports_enable(export);
+
+ add_trace_export(list, export);
+}
+
+static inline int
+rm_ftrace_export(struct trace_export **list, struct trace_export *export)
+{
+ int ret;
+
+ ret = rm_trace_export(list, export);
+ ftrace_exports_disable(export);
+
+ return ret;
+}
+
+int register_ftrace_export(struct trace_export *export)
+{
+ if (WARN_ON_ONCE(!export->write))
+ return -1;
+
+ mutex_lock(&ftrace_export_lock);
+
+ add_ftrace_export(&ftrace_exports_list, export);
+
+ mutex_unlock(&ftrace_export_lock);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(register_ftrace_export);
+
+int unregister_ftrace_export(struct trace_export *export)
+{
+ int ret;
+
+ mutex_lock(&ftrace_export_lock);
+
+ ret = rm_ftrace_export(&ftrace_exports_list, export);
+
+ mutex_unlock(&ftrace_export_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(unregister_ftrace_export);
+
/* trace_flags holds trace_options default values */
#define TRACE_DEFAULT_FLAGS \
(FUNCTION_DEFAULT_FLAGS | \
@@ -2702,6 +2834,8 @@ void trace_event_buffer_commit(struct trace_event_buffer *fbuffer)
if (static_key_false(&tracepoint_printk_key.key))
output_printk(fbuffer);
+ if (static_branch_unlikely(&trace_event_exports_enabled))
+ ftrace_exports(fbuffer->event, TRACE_EXPORT_EVENT);
event_trigger_unlock_commit_regs(fbuffer->trace_file, fbuffer->buffer,
fbuffer->event, fbuffer->entry,
fbuffer->flags, fbuffer->pc, fbuffer->regs);
@@ -2745,131 +2879,6 @@ trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer,
__buffer_unlock_commit(buffer, event);
}
-static void
-trace_process_export(struct trace_export *export,
- struct ring_buffer_event *event, int flag)
-{
- struct trace_entry *entry;
- unsigned int size = 0;
-
- if (export->flags & flag) {
- entry = ring_buffer_event_data(event);
- size = ring_buffer_event_length(event);
- export->write(export, entry, size);
- }
-}
-
-static DEFINE_MUTEX(ftrace_export_lock);
-
-static struct trace_export __rcu *ftrace_exports_list __read_mostly;
-
-static DEFINE_STATIC_KEY_FALSE(trace_function_exports_enabled);
-
-static inline void ftrace_exports_enable(struct trace_export *export)
-{
- if (export->flags & TRACE_EXPORT_FUNCTION)
- static_branch_inc(&trace_function_exports_enabled);
-}
-
-static inline void ftrace_exports_disable(struct trace_export *export)
-{
- if (export->flags & TRACE_EXPORT_FUNCTION)
- static_branch_dec(&trace_function_exports_enabled);
-}
-
-static void ftrace_exports(struct ring_buffer_event *event, int flag)
-{
- struct trace_export *export;
-
- preempt_disable_notrace();
-
- export = rcu_dereference_raw_check(ftrace_exports_list);
- while (export) {
- trace_process_export(export, event, flag);
- export = rcu_dereference_raw_check(export->next);
- }
-
- preempt_enable_notrace();
-}
-
-static inline void
-add_trace_export(struct trace_export **list, struct trace_export *export)
-{
- rcu_assign_pointer(export->next, *list);
- /*
- * We are entering export into the list but another
- * CPU might be walking that list. We need to make sure
- * the export->next pointer is valid before another CPU sees
- * the export pointer included into the list.
- */
- rcu_assign_pointer(*list, export);
-}
-
-static inline int
-rm_trace_export(struct trace_export **list, struct trace_export *export)
-{
- struct trace_export **p;
-
- for (p = list; *p != NULL; p = &(*p)->next)
- if (*p == export)
- break;
-
- if (*p != export)
- return -1;
-
- rcu_assign_pointer(*p, (*p)->next);
-
- return 0;
-}
-
-static inline void
-add_ftrace_export(struct trace_export **list, struct trace_export *export)
-{
- ftrace_exports_enable(export);
-
- add_trace_export(list, export);
-}
-
-static inline int
-rm_ftrace_export(struct trace_export **list, struct trace_export *export)
-{
- int ret;
-
- ret = rm_trace_export(list, export);
- ftrace_exports_disable(export);
-
- return ret;
-}
-
-int register_ftrace_export(struct trace_export *export)
-{
- if (WARN_ON_ONCE(!export->write))
- return -1;
-
- mutex_lock(&ftrace_export_lock);
-
- add_ftrace_export(&ftrace_exports_list, export);
-
- mutex_unlock(&ftrace_export_lock);
-
- return 0;
-}
-EXPORT_SYMBOL_GPL(register_ftrace_export);
-
-int unregister_ftrace_export(struct trace_export *export)
-{
- int ret;
-
- mutex_lock(&ftrace_export_lock);
-
- ret = rm_ftrace_export(&ftrace_exports_list, export);
-
- mutex_unlock(&ftrace_export_lock);
-
- return ret;
-}
-EXPORT_SYMBOL_GPL(unregister_ftrace_export);
-
void
trace_function(struct trace_array *tr,
unsigned long ip, unsigned long parent_ip, unsigned long flags,
--
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project
^ permalink raw reply related [flat|nested] 25+ messages in thread
* [PATCH v3 4/6] tracing: add trace_export support for trace_marker
2020-09-03 0:17 ` Tingwei Zhang
@ 2020-09-03 0:17 ` Tingwei Zhang
-1 siblings, 0 replies; 25+ messages in thread
From: Tingwei Zhang @ 2020-09-03 0:17 UTC (permalink / raw)
To: Steven Rostedt, Ingo Molnar, Alexander Shishkin, Maxime Coquelin,
Alexandre Torgue
Cc: tsoni, Sai Prakash Ranjan, Mathieu Poirier, Suzuki K Poulose,
Mao Jinlong, linux-kernel, Tingwei Zhang, linux-stm32,
linux-arm-kernel
Add the support to route trace_marker buffer to other destination
via trace_export.
Signed-off-by: Tingwei Zhang <tingwei@codeaurora.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
include/linux/trace.h | 1 +
kernel/trace/trace.c | 9 +++++++++
2 files changed, 10 insertions(+)
diff --git a/include/linux/trace.h b/include/linux/trace.h
index 5a01eeffb254..80b7df68bc0f 100644
--- a/include/linux/trace.h
+++ b/include/linux/trace.h
@@ -6,6 +6,7 @@
#define TRACE_EXPORT_FUNCTION BIT(0)
#define TRACE_EXPORT_EVENT BIT(1)
+#define TRACE_EXPORT_MARKER BIT(2)
/*
* The trace export - an export of Ftrace output. The trace_export
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 2f9302a8b322..67993abda394 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -271,6 +271,7 @@ static struct trace_export __rcu *ftrace_exports_list __read_mostly;
static DEFINE_STATIC_KEY_FALSE(trace_function_exports_enabled);
static DEFINE_STATIC_KEY_FALSE(trace_event_exports_enabled);
+static DEFINE_STATIC_KEY_FALSE(trace_marker_exports_enabled);
static inline void ftrace_exports_enable(struct trace_export *export)
{
@@ -279,6 +280,9 @@ static inline void ftrace_exports_enable(struct trace_export *export)
if (export->flags & TRACE_EXPORT_EVENT)
static_branch_inc(&trace_event_exports_enabled);
+
+ if (export->flags & TRACE_EXPORT_MARKER)
+ static_branch_inc(&trace_marker_exports_enabled);
}
static inline void ftrace_exports_disable(struct trace_export *export)
@@ -288,6 +292,9 @@ static inline void ftrace_exports_disable(struct trace_export *export)
if (export->flags & TRACE_EXPORT_EVENT)
static_branch_dec(&trace_event_exports_enabled);
+
+ if (export->flags & TRACE_EXPORT_MARKER)
+ static_branch_dec(&trace_marker_exports_enabled);
}
static void ftrace_exports(struct ring_buffer_event *event, int flag)
@@ -6648,6 +6655,8 @@ tracing_mark_write(struct file *filp, const char __user *ubuf,
} else
entry->buf[cnt] = '\0';
+ if (static_branch_unlikely(&trace_marker_exports_enabled))
+ ftrace_exports(event, TRACE_EXPORT_MARKER);
__buffer_unlock_commit(buffer, event);
if (tt)
--
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply related [flat|nested] 25+ messages in thread* [PATCH v3 4/6] tracing: add trace_export support for trace_marker
@ 2020-09-03 0:17 ` Tingwei Zhang
0 siblings, 0 replies; 25+ messages in thread
From: Tingwei Zhang @ 2020-09-03 0:17 UTC (permalink / raw)
To: Steven Rostedt, Ingo Molnar, Alexander Shishkin, Maxime Coquelin,
Alexandre Torgue
Cc: Tingwei Zhang, Mathieu Poirier, Suzuki K Poulose, tsoni,
Sai Prakash Ranjan, Mao Jinlong, linux-kernel, linux-stm32,
linux-arm-kernel
Add the support to route trace_marker buffer to other destination
via trace_export.
Signed-off-by: Tingwei Zhang <tingwei@codeaurora.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
include/linux/trace.h | 1 +
kernel/trace/trace.c | 9 +++++++++
2 files changed, 10 insertions(+)
diff --git a/include/linux/trace.h b/include/linux/trace.h
index 5a01eeffb254..80b7df68bc0f 100644
--- a/include/linux/trace.h
+++ b/include/linux/trace.h
@@ -6,6 +6,7 @@
#define TRACE_EXPORT_FUNCTION BIT(0)
#define TRACE_EXPORT_EVENT BIT(1)
+#define TRACE_EXPORT_MARKER BIT(2)
/*
* The trace export - an export of Ftrace output. The trace_export
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 2f9302a8b322..67993abda394 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -271,6 +271,7 @@ static struct trace_export __rcu *ftrace_exports_list __read_mostly;
static DEFINE_STATIC_KEY_FALSE(trace_function_exports_enabled);
static DEFINE_STATIC_KEY_FALSE(trace_event_exports_enabled);
+static DEFINE_STATIC_KEY_FALSE(trace_marker_exports_enabled);
static inline void ftrace_exports_enable(struct trace_export *export)
{
@@ -279,6 +280,9 @@ static inline void ftrace_exports_enable(struct trace_export *export)
if (export->flags & TRACE_EXPORT_EVENT)
static_branch_inc(&trace_event_exports_enabled);
+
+ if (export->flags & TRACE_EXPORT_MARKER)
+ static_branch_inc(&trace_marker_exports_enabled);
}
static inline void ftrace_exports_disable(struct trace_export *export)
@@ -288,6 +292,9 @@ static inline void ftrace_exports_disable(struct trace_export *export)
if (export->flags & TRACE_EXPORT_EVENT)
static_branch_dec(&trace_event_exports_enabled);
+
+ if (export->flags & TRACE_EXPORT_MARKER)
+ static_branch_dec(&trace_marker_exports_enabled);
}
static void ftrace_exports(struct ring_buffer_event *event, int flag)
@@ -6648,6 +6655,8 @@ tracing_mark_write(struct file *filp, const char __user *ubuf,
} else
entry->buf[cnt] = '\0';
+ if (static_branch_unlikely(&trace_marker_exports_enabled))
+ ftrace_exports(event, TRACE_EXPORT_MARKER);
__buffer_unlock_commit(buffer, event);
if (tt)
--
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project
^ permalink raw reply related [flat|nested] 25+ messages in thread
* [PATCH v3 5/6] stm class: ftrace: enable supported trace export flag
2020-09-03 0:17 ` Tingwei Zhang
@ 2020-09-03 0:17 ` Tingwei Zhang
-1 siblings, 0 replies; 25+ messages in thread
From: Tingwei Zhang @ 2020-09-03 0:17 UTC (permalink / raw)
To: Steven Rostedt, Ingo Molnar, Alexander Shishkin, Maxime Coquelin,
Alexandre Torgue
Cc: tsoni, Sai Prakash Ranjan, Mathieu Poirier, Suzuki K Poulose,
Mao Jinlong, linux-kernel, Tingwei Zhang, linux-stm32,
linux-arm-kernel
Set flags for trace_export. Export function trace, event trace
and trace marker to stm.
Signed-off-by: Tingwei Zhang <tingwei@codeaurora.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
drivers/hwtracing/stm/ftrace.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/hwtracing/stm/ftrace.c b/drivers/hwtracing/stm/ftrace.c
index ce868e095410..c694a6e692d1 100644
--- a/drivers/hwtracing/stm/ftrace.c
+++ b/drivers/hwtracing/stm/ftrace.c
@@ -46,6 +46,8 @@ static int stm_ftrace_link(struct stm_source_data *data)
struct stm_ftrace *sf = container_of(data, struct stm_ftrace, data);
sf->ftrace.write = stm_ftrace_write;
+ sf->ftrace.flags = TRACE_EXPORT_FUNCTION | TRACE_EXPORT_EVENT
+ | TRACE_EXPORT_MARKER;
return register_ftrace_export(&sf->ftrace);
}
--
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply related [flat|nested] 25+ messages in thread
* [PATCH v3 5/6] stm class: ftrace: enable supported trace export flag
@ 2020-09-03 0:17 ` Tingwei Zhang
0 siblings, 0 replies; 25+ messages in thread
From: Tingwei Zhang @ 2020-09-03 0:17 UTC (permalink / raw)
To: Steven Rostedt, Ingo Molnar, Alexander Shishkin, Maxime Coquelin,
Alexandre Torgue
Cc: Tingwei Zhang, Mathieu Poirier, Suzuki K Poulose, tsoni,
Sai Prakash Ranjan, Mao Jinlong, linux-kernel, linux-stm32,
linux-arm-kernel
Set flags for trace_export. Export function trace, event trace
and trace marker to stm.
Signed-off-by: Tingwei Zhang <tingwei@codeaurora.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
drivers/hwtracing/stm/ftrace.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/hwtracing/stm/ftrace.c b/drivers/hwtracing/stm/ftrace.c
index ce868e095410..c694a6e692d1 100644
--- a/drivers/hwtracing/stm/ftrace.c
+++ b/drivers/hwtracing/stm/ftrace.c
@@ -46,6 +46,8 @@ static int stm_ftrace_link(struct stm_source_data *data)
struct stm_ftrace *sf = container_of(data, struct stm_ftrace, data);
sf->ftrace.write = stm_ftrace_write;
+ sf->ftrace.flags = TRACE_EXPORT_FUNCTION | TRACE_EXPORT_EVENT
+ | TRACE_EXPORT_MARKER;
return register_ftrace_export(&sf->ftrace);
}
--
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project
^ permalink raw reply related [flat|nested] 25+ messages in thread
* [PATCH v3 6/6] stm class: ftrace: use different channel accroding to CPU
2020-09-03 0:17 ` Tingwei Zhang
@ 2020-09-03 0:17 ` Tingwei Zhang
-1 siblings, 0 replies; 25+ messages in thread
From: Tingwei Zhang @ 2020-09-03 0:17 UTC (permalink / raw)
To: Steven Rostedt, Ingo Molnar, Alexander Shishkin, Maxime Coquelin,
Alexandre Torgue
Cc: tsoni, Sai Prakash Ranjan, Mathieu Poirier, Suzuki K Poulose,
Mao Jinlong, linux-kernel, Tingwei Zhang, linux-stm32,
linux-arm-kernel
To avoid mixup of packets from differnt ftrace packets simultaneously,
use different channel for packets from different CPU.
Signed-off-by: Tingwei Zhang <tingwei@codeaurora.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
drivers/hwtracing/stm/ftrace.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/hwtracing/stm/ftrace.c b/drivers/hwtracing/stm/ftrace.c
index c694a6e692d1..ebf29489919c 100644
--- a/drivers/hwtracing/stm/ftrace.c
+++ b/drivers/hwtracing/stm/ftrace.c
@@ -37,8 +37,10 @@ static void notrace
stm_ftrace_write(struct trace_export *export, const void *buf, unsigned int len)
{
struct stm_ftrace *stm = container_of(export, struct stm_ftrace, ftrace);
+ /* This is called from trace system with preemption disabled */
+ unsigned int cpu = smp_processor_id();
- stm_source_write(&stm->data, STM_FTRACE_CHAN, buf, len);
+ stm_source_write(&stm->data, STM_FTRACE_CHAN + cpu, buf, len);
}
static int stm_ftrace_link(struct stm_source_data *data)
@@ -63,6 +65,7 @@ static int __init stm_ftrace_init(void)
{
int ret;
+ stm_ftrace.data.nr_chans = num_possible_cpus();
ret = stm_source_register_device(NULL, &stm_ftrace.data);
if (ret)
pr_err("Failed to register stm_source - ftrace.\n");
--
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply related [flat|nested] 25+ messages in thread* [PATCH v3 6/6] stm class: ftrace: use different channel accroding to CPU
@ 2020-09-03 0:17 ` Tingwei Zhang
0 siblings, 0 replies; 25+ messages in thread
From: Tingwei Zhang @ 2020-09-03 0:17 UTC (permalink / raw)
To: Steven Rostedt, Ingo Molnar, Alexander Shishkin, Maxime Coquelin,
Alexandre Torgue
Cc: Tingwei Zhang, Mathieu Poirier, Suzuki K Poulose, tsoni,
Sai Prakash Ranjan, Mao Jinlong, linux-kernel, linux-stm32,
linux-arm-kernel
To avoid mixup of packets from differnt ftrace packets simultaneously,
use different channel for packets from different CPU.
Signed-off-by: Tingwei Zhang <tingwei@codeaurora.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
drivers/hwtracing/stm/ftrace.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/hwtracing/stm/ftrace.c b/drivers/hwtracing/stm/ftrace.c
index c694a6e692d1..ebf29489919c 100644
--- a/drivers/hwtracing/stm/ftrace.c
+++ b/drivers/hwtracing/stm/ftrace.c
@@ -37,8 +37,10 @@ static void notrace
stm_ftrace_write(struct trace_export *export, const void *buf, unsigned int len)
{
struct stm_ftrace *stm = container_of(export, struct stm_ftrace, ftrace);
+ /* This is called from trace system with preemption disabled */
+ unsigned int cpu = smp_processor_id();
- stm_source_write(&stm->data, STM_FTRACE_CHAN, buf, len);
+ stm_source_write(&stm->data, STM_FTRACE_CHAN + cpu, buf, len);
}
static int stm_ftrace_link(struct stm_source_data *data)
@@ -63,6 +65,7 @@ static int __init stm_ftrace_init(void)
{
int ret;
+ stm_ftrace.data.nr_chans = num_possible_cpus();
ret = stm_source_register_device(NULL, &stm_ftrace.data);
if (ret)
pr_err("Failed to register stm_source - ftrace.\n");
--
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project
^ permalink raw reply related [flat|nested] 25+ messages in thread* Re: [PATCH v3 6/6] stm class: ftrace: use different channel accroding to CPU
2020-09-03 0:17 ` Tingwei Zhang
@ 2020-09-18 12:45 ` Alexander Shishkin
-1 siblings, 0 replies; 25+ messages in thread
From: Alexander Shishkin @ 2020-09-18 12:45 UTC (permalink / raw)
To: Tingwei Zhang, Steven Rostedt, Ingo Molnar, Maxime Coquelin,
Alexandre Torgue
Cc: tsoni, Sai Prakash Ranjan, Mathieu Poirier, Suzuki K Poulose,
alexander.shishkin, Mao Jinlong, linux-kernel, Tingwei Zhang,
linux-stm32, linux-arm-kernel
Tingwei Zhang <tingwei@codeaurora.org> writes:
> @@ -63,6 +65,7 @@ static int __init stm_ftrace_init(void)
> {
> int ret;
>
> + stm_ftrace.data.nr_chans = num_possible_cpus();
Not a problem with this patch necesarily, but this made me realize that
.nr_chans may be larger than:
(1) what the policy permits,
(2) what the stm device can handle.
While (1) the user can fix in the policy, they won't be able to fix (2),
in which case they won't be able to use stm_ftrace at all. I'm thinking
if a link-time callback would be good enough.
Another thing is that .nr_chans needs to be a power of 2 at the moment.
Regards,
--
Alex
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 25+ messages in thread* Re: [PATCH v3 6/6] stm class: ftrace: use different channel accroding to CPU
@ 2020-09-18 12:45 ` Alexander Shishkin
0 siblings, 0 replies; 25+ messages in thread
From: Alexander Shishkin @ 2020-09-18 12:45 UTC (permalink / raw)
To: Tingwei Zhang, Steven Rostedt, Ingo Molnar, Maxime Coquelin,
Alexandre Torgue
Cc: Tingwei Zhang, Mathieu Poirier, Suzuki K Poulose, tsoni,
Sai Prakash Ranjan, Mao Jinlong, linux-kernel, linux-stm32,
linux-arm-kernel, alexander.shishkin
Tingwei Zhang <tingwei@codeaurora.org> writes:
> @@ -63,6 +65,7 @@ static int __init stm_ftrace_init(void)
> {
> int ret;
>
> + stm_ftrace.data.nr_chans = num_possible_cpus();
Not a problem with this patch necesarily, but this made me realize that
.nr_chans may be larger than:
(1) what the policy permits,
(2) what the stm device can handle.
While (1) the user can fix in the policy, they won't be able to fix (2),
in which case they won't be able to use stm_ftrace at all. I'm thinking
if a link-time callback would be good enough.
Another thing is that .nr_chans needs to be a power of 2 at the moment.
Regards,
--
Alex
^ permalink raw reply [flat|nested] 25+ messages in thread* Re: [PATCH v3 6/6] stm class: ftrace: use different channel accroding to CPU
2020-09-18 12:45 ` Alexander Shishkin
@ 2020-09-23 4:39 ` Tingwei Zhang
-1 siblings, 0 replies; 25+ messages in thread
From: Tingwei Zhang @ 2020-09-23 4:39 UTC (permalink / raw)
To: Alexander Shishkin
Cc: tsoni, Sai Prakash Ranjan, Tingwei Zhang, Mathieu Poirier,
Suzuki K Poulose, Mao Jinlong, linux-kernel, Steven Rostedt,
Ingo Molnar, Maxime Coquelin, linux-stm32, linux-arm-kernel,
Alexandre Torgue
On Fri, Sep 18, 2020 at 08:45:52PM +0800, Alexander Shishkin wrote:
> Tingwei Zhang <tingwei@codeaurora.org> writes:
>
> > @@ -63,6 +65,7 @@ static int __init stm_ftrace_init(void)
> > {
> > int ret;
> >
> > + stm_ftrace.data.nr_chans = num_possible_cpus();
>
> Not a problem with this patch necesarily, but this made me realize that
> .nr_chans may be larger than:
>
> (1) what the policy permits,
> (2) what the stm device can handle.
>
> While (1) the user can fix in the policy, they won't be able to fix (2),
> in which case they won't be able to use stm_ftrace at all. I'm thinking
> if a link-time callback would be good enough.
>
Hi Alex,
I'm not sure if I understand this correct. If the nr_chans requested by
stm_ftrace is larger than policy permits or stm device can handle,
stm_assign_first_policy() returns with error so stm_source_link_add()
will fail. User would notice that when link happens. There's not much
we can do if resource is not enough.
> Another thing is that .nr_chans needs to be a power of 2 at the moment.
>
I'll change to below.
stm_ftrace.data.nr_chans = roundup_pow_of_two(num_possible_cpus());
> Regards,
> --
> Alex
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 25+ messages in thread* Re: [PATCH v3 6/6] stm class: ftrace: use different channel accroding to CPU
@ 2020-09-23 4:39 ` Tingwei Zhang
0 siblings, 0 replies; 25+ messages in thread
From: Tingwei Zhang @ 2020-09-23 4:39 UTC (permalink / raw)
To: Alexander Shishkin
Cc: Tingwei Zhang, Steven Rostedt, Ingo Molnar, Maxime Coquelin,
Alexandre Torgue, tsoni, Sai Prakash Ranjan, Mathieu Poirier,
Suzuki K Poulose, Mao Jinlong, linux-kernel, linux-stm32,
linux-arm-kernel
On Fri, Sep 18, 2020 at 08:45:52PM +0800, Alexander Shishkin wrote:
> Tingwei Zhang <tingwei@codeaurora.org> writes:
>
> > @@ -63,6 +65,7 @@ static int __init stm_ftrace_init(void)
> > {
> > int ret;
> >
> > + stm_ftrace.data.nr_chans = num_possible_cpus();
>
> Not a problem with this patch necesarily, but this made me realize that
> .nr_chans may be larger than:
>
> (1) what the policy permits,
> (2) what the stm device can handle.
>
> While (1) the user can fix in the policy, they won't be able to fix (2),
> in which case they won't be able to use stm_ftrace at all. I'm thinking
> if a link-time callback would be good enough.
>
Hi Alex,
I'm not sure if I understand this correct. If the nr_chans requested by
stm_ftrace is larger than policy permits or stm device can handle,
stm_assign_first_policy() returns with error so stm_source_link_add()
will fail. User would notice that when link happens. There's not much
we can do if resource is not enough.
> Another thing is that .nr_chans needs to be a power of 2 at the moment.
>
I'll change to below.
stm_ftrace.data.nr_chans = roundup_pow_of_two(num_possible_cpus());
> Regards,
> --
> Alex
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 25+ messages in thread
* Re: [PATCH v3 0/6] tracing: export event trace and trace_marker
2020-09-03 0:17 ` Tingwei Zhang
@ 2020-09-14 23:27 ` Tingwei Zhang
-1 siblings, 0 replies; 25+ messages in thread
From: Tingwei Zhang @ 2020-09-14 23:27 UTC (permalink / raw)
To: Tingwei Zhang
Cc: tsoni, Sai Prakash Ranjan, Alexandre Torgue, Mathieu Poirier,
Suzuki K Poulose, Alexander Shishkin, Mao Jinlong, linux-kernel,
Steven Rostedt, Ingo Molnar, Maxime Coquelin, linux-stm32,
linux-arm-kernel
Hi Alexander, Maxime, Aleandre,
May I know your comments for this patch set?
Thanks,
Tingwei
On Thu, Sep 03, 2020 at 08:17:00AM +0800, Tingwei Zhang wrote:
> Ftrace has ability to export trace packets to other destination.
> Currently, only function trace can be exported. This series extends the
> support to event trace and trace_maker. STM is one possible destination to
> export ftrace. Use separate channel for each CPU to avoid mixing up
> packets
> from different CPUs together.
>
> Change from v2:
> Change flag definition to BIT(). (Steven)
> Add comment in stm_ftrace_write() to clarify it's safe to use
> smp_processor_id() here since preempt is disabled. (Steven)
>
> Change from v1:
> All changes are suggested by Steven Rostedt.
> User separate flag to control function trace, event trace and trace mark.
> Allocate channels according to num_possible_cpu() dynamically.
> Move ftrace_exports routines up so all ftrace can use them.
>
> Tingwei Zhang (6):
> stm class: ftrace: change dependency to TRACING
> tracing: add flag to control different traces
> tracing: add trace_export support for event trace
> tracing: add trace_export support for trace_marker
> stm class: ftrace: enable supported trace export flag
> stm class: ftrace: use different channel accroding to CPU
>
> drivers/hwtracing/stm/Kconfig | 2 +-
> drivers/hwtracing/stm/ftrace.c | 7 +-
> include/linux/trace.h | 7 +
> kernel/trace/trace.c | 270 ++++++++++++++++++---------------
> 4 files changed, 159 insertions(+), 127 deletions(-)
>
> --
> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
> a Linux Foundation Collaborative Project
>
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 25+ messages in thread
* Re: [PATCH v3 0/6] tracing: export event trace and trace_marker
@ 2020-09-14 23:27 ` Tingwei Zhang
0 siblings, 0 replies; 25+ messages in thread
From: Tingwei Zhang @ 2020-09-14 23:27 UTC (permalink / raw)
To: Tingwei Zhang
Cc: Steven Rostedt, Ingo Molnar, Alexander Shishkin, Maxime Coquelin,
Alexandre Torgue, Mathieu Poirier, Suzuki K Poulose, tsoni,
Sai Prakash Ranjan, Mao Jinlong, linux-kernel, linux-stm32,
linux-arm-kernel
Hi Alexander, Maxime, Aleandre,
May I know your comments for this patch set?
Thanks,
Tingwei
On Thu, Sep 03, 2020 at 08:17:00AM +0800, Tingwei Zhang wrote:
> Ftrace has ability to export trace packets to other destination.
> Currently, only function trace can be exported. This series extends the
> support to event trace and trace_maker. STM is one possible destination to
> export ftrace. Use separate channel for each CPU to avoid mixing up
> packets
> from different CPUs together.
>
> Change from v2:
> Change flag definition to BIT(). (Steven)
> Add comment in stm_ftrace_write() to clarify it's safe to use
> smp_processor_id() here since preempt is disabled. (Steven)
>
> Change from v1:
> All changes are suggested by Steven Rostedt.
> User separate flag to control function trace, event trace and trace mark.
> Allocate channels according to num_possible_cpu() dynamically.
> Move ftrace_exports routines up so all ftrace can use them.
>
> Tingwei Zhang (6):
> stm class: ftrace: change dependency to TRACING
> tracing: add flag to control different traces
> tracing: add trace_export support for event trace
> tracing: add trace_export support for trace_marker
> stm class: ftrace: enable supported trace export flag
> stm class: ftrace: use different channel accroding to CPU
>
> drivers/hwtracing/stm/Kconfig | 2 +-
> drivers/hwtracing/stm/ftrace.c | 7 +-
> include/linux/trace.h | 7 +
> kernel/trace/trace.c | 270 ++++++++++++++++++---------------
> 4 files changed, 159 insertions(+), 127 deletions(-)
>
> --
> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
> a Linux Foundation Collaborative Project
>
^ permalink raw reply [flat|nested] 25+ messages in thread
* Re: [PATCH v3 0/6] tracing: export event trace and trace_marker
2020-09-14 23:27 ` Tingwei Zhang
@ 2020-09-18 14:26 ` Alexander Shishkin
-1 siblings, 0 replies; 25+ messages in thread
From: Alexander Shishkin @ 2020-09-18 14:26 UTC (permalink / raw)
To: Tingwei Zhang, Tingwei Zhang
Cc: tsoni, Sai Prakash Ranjan, Alexandre Torgue, Mathieu Poirier,
Suzuki K Poulose, alexander.shishkin, Mao Jinlong, linux-kernel,
Steven Rostedt, Ingo Molnar, Maxime Coquelin, linux-stm32,
linux-arm-kernel
Tingwei Zhang <tingweiz@codeaurora.org> writes:
> Hi Alexander, Maxime, Aleandre,
>
> May I know your comments for this patch set?
Everything except the last patch is
Reviewed-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
After that one is resolved either I can pick it up or Stephen. Either
way is fine with me.
Regards,
--
Alex
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 25+ messages in thread
* Re: [PATCH v3 0/6] tracing: export event trace and trace_marker
@ 2020-09-18 14:26 ` Alexander Shishkin
0 siblings, 0 replies; 25+ messages in thread
From: Alexander Shishkin @ 2020-09-18 14:26 UTC (permalink / raw)
To: Tingwei Zhang, Tingwei Zhang
Cc: Steven Rostedt, Ingo Molnar, Maxime Coquelin, Alexandre Torgue,
Mathieu Poirier, Suzuki K Poulose, tsoni, Sai Prakash Ranjan,
Mao Jinlong, linux-kernel, linux-stm32, linux-arm-kernel,
alexander.shishkin
Tingwei Zhang <tingweiz@codeaurora.org> writes:
> Hi Alexander, Maxime, Aleandre,
>
> May I know your comments for this patch set?
Everything except the last patch is
Reviewed-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
After that one is resolved either I can pick it up or Stephen. Either
way is fine with me.
Regards,
--
Alex
^ permalink raw reply [flat|nested] 25+ messages in thread