Re: [RESEND PATCH v6 14/14] drm/print: Add tracefs support to the drm logging helpers

2021-09-17 Thread abhinavk 

On 2021-07-21 10:55, Sean Paul wrote:

From: Sean Paul 

This patch adds a new module parameter called drm.trace which accepts
the same mask as drm.debug. When a debug category is enabled, log
messages will be put in a new tracefs instance called drm for
consumption.

Using the new tracefs instance will allow distros to enable drm logging
in production without impacting performance or spamming the system
logs.

Cc: Daniel Vetter 
Cc: David Airlie 
Cc: Jani Nikula 
Cc: Joonas Lahtinen 
Cc: Pekka Paalanen 
Cc: Rob Clark 
Cc: Steven Rostedt 
Cc: Thomas Zimmermann 
Cc: Ville Syrjälä 
Cc: Chris Wilson 
Cc: Steven Rostedt 
Reported-by: kernel test robot  # warning reported in v6
Acked-by: Pekka Paalanen 
Signed-off-by: Sean Paul 
Link:
https://patchwork.freedesktop.org/patch/msgid/20191010204823.195540-1-s...@poorly.run
#v1
Link:
https://lists.freedesktop.org/archives/dri-devel/2019-November/243230.html
#v2
Link:
https://patchwork.freedesktop.org/patch/msgid/20191212203301.142437-1-s...@poorly.run
#v3
Link:
https://patchwork.freedesktop.org/patch/msgid/20200114172155.215463-1-s...@poorly.run
#v4
Link:
https://patchwork.freedesktop.org/patch/msgid/20200608210505.48519-14-s...@poorly.run
#v5
Link:
https://patchwork.freedesktop.org/patch/msgid/20200818210510.49730-15-s...@poorly.run
#v6

Changes in v5:
-Re-write to use trace_array and the tracefs instance support
Changes in v6:
-Use the new trace_array_init_printk() to initialize global trace
 buffers
Changes in v6.5:
-Fix kernel test robot warning
-Add a trace printf in __drm_err
---
 Documentation/gpu/drm-uapi.rst |   6 +
 drivers/gpu/drm/drm_drv.c  |   3 +
 drivers/gpu/drm/drm_print.c| 223 -
 include/drm/drm_print.h|  63 --
 4 files changed, 255 insertions(+), 40 deletions(-)

diff --git a/Documentation/gpu/drm-uapi.rst 
b/Documentation/gpu/drm-uapi.rst

index 7e51dd40bf6e..ce1ea39fb4b9 100644
--- a/Documentation/gpu/drm-uapi.rst
+++ b/Documentation/gpu/drm-uapi.rst
@@ -424,6 +424,12 @@ Debugfs Support
 .. kernel-doc:: drivers/gpu/drm/drm_debugfs.c
:export:

+DRM Tracing
+---
+
+.. kernel-doc:: drivers/gpu/drm/drm_print.c
+   :doc: DRM Tracing
+
 Sysfs Support
 =

diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
index 8804ec7d3215..71dc0b161b51 100644
--- a/drivers/gpu/drm/drm_drv.c
+++ b/drivers/gpu/drm/drm_drv.c
@@ -1034,12 +1034,15 @@ static void drm_core_exit(void)
drm_sysfs_destroy();
idr_destroy(_minors_idr);
drm_connector_ida_destroy();
+   drm_trace_cleanup();
 }

 static int __init drm_core_init(void)
 {
int ret;

+   drm_trace_init();


Can we move the drm_trace_init() to drm_dev_register()?
The reason is while creating the tracefs node, I think its useful to 
have the drm device id to support
multiple DRM devices. So while creating the tracefs node, we can do 
something like

trace_array_get_by_name("drm_
+
drm_connector_ida_init();
idr_init(_minors_idr);
drm_memcpy_init_early();
diff --git a/drivers/gpu/drm/drm_print.c b/drivers/gpu/drm/drm_print.c
index 4d984a01b3a3..64d9a724c2df 100644
--- a/drivers/gpu/drm/drm_print.c
+++ b/drivers/gpu/drm/drm_print.c
@@ -31,6 +31,7 @@
 #include 
 #include 
 #include 
+#include 

 #include 
 #include 
@@ -43,17 +44,34 @@
 unsigned int __drm_debug_syslog;
 EXPORT_SYMBOL(__drm_debug_syslog);

-MODULE_PARM_DESC(debug, "Enable debug output, where each bit enables
a debug category.\n"
-"\t\tBit 0 (0x01)  will enable CORE messages (drm core code)\n"
-"\t\tBit 1 (0x02)  will enable DRIVER messages (drm controller 
code)\n"

-"\t\tBit 2 (0x04)  will enable KMS messages (modesetting code)\n"
-"\t\tBit 3 (0x08)  will enable PRIME messages (prime code)\n"
-"\t\tBit 4 (0x10)  will enable ATOMIC messages (atomic code)\n"
-"\t\tBit 5 (0x20)  will enable VBL messages (vblank code)\n"
-"\t\tBit 7 (0x80)  will enable LEASE messages (leasing code)\n"
-"\t\tBit 8 (0x100) will enable DP messages (displayport code)");
+/*
+ * __drm_debug_trace: Enable debug output in drm tracing instance.
+ * Bitmask of DRM_UT_x. See include/drm/drm_print.h for details.
+ */
+unsigned int __drm_debug_trace;
+EXPORT_SYMBOL(__drm_debug_trace);
+
+#define DEBUG_PARM_DESC(dst) \
+"Enable debug output to " dst ", where each bit enables a debug 
category.\n" \

+"\t\tBit 0 (0x01)  will enable CORE messages (drm core code)\n" \
+"\t\tBit 1 (0x02)  will enable DRIVER messages (drm controller 
code)\n" \

+"\t\tBit 2 (0x04)  will enable KMS messages (modesetting code)\n" \
+"\t\tBit 3 (0x08)  will enable PRIME messages (prime code)\n" \
+"\t\tBit 4 (0x10)  will enable ATOMIC messages (atomic code)\n" \
+"\t\tBit 5 (0x20)  will enable VBL messages (vblank code)\n" \
+"\t\tBit 7 (0x80)  will enable LEASE messages (leasing code)\n" \
+"\t\tBit 8 (0x100) will enable DP messages (displayport code)"


This is certainly a great start. Moving forward a bit, is there a 
possibility to subcatergorize

Re: [RESEND PATCH v6 14/14] drm/print: Add tracefs support to the drm logging helpers

2021-07-29 Thread jim . cromie 
On Thu, Jul 29, 2021 at 2:24 PM  wrote:
>
> On Wed, Jul 21, 2021 at 11:56 AM Sean Paul  wrote:
> >
> > From: Sean Paul 
> >
> > This patch adds a new module parameter called drm.trace which accepts
> > the same mask as drm.debug. When a debug category is enabled, log
> > messages will be put in a new tracefs instance called drm for
> > consumption.
> >
> > Using the new tracefs instance will allow distros to enable drm logging
> > in production without impacting performance or spamming the system
> > logs.
>
> hi Paul,
>
> I should have started reading here, not at patch-1
> While I still think some of the _syslog name changes are extra,
> drm_debug_enabled() needs it - rename goes with narrower purpose.
>
> a couple comments below, trimming heavily.
>
>
> > +#define DEBUG_PARM_DESC(dst) \
> > +"Enable debug output to " dst ", where each bit enables a debug 
> > category.\n" \
>
> I will be borrowing that idea.
>
> > +
> > +MODULE_PARM_DESC(debug, DEBUG_PARM_DESC("syslog"));
> >  module_param_named(debug, __drm_debug_syslog, int, 0600);
> >
>
>
> > +void __drm_printfn_debug_syslog_and_trace(struct drm_printer *p,
> > +  struct va_format *vaf)
> > +{
> > +   pr_debug("%s %pV", p->prefix, vaf);
>
> Im not sure about prefixing this way.
> dyndbg query needs to see the prefix in the format string at compile-time.
>
> My RFC patch does the prefixing in the macro layer, when enabled.
> when disabled, prefixing at runtime is fine.
> This looks easy to shake out..
>

Actually, this is more problematic than that.
this pr_debug has just a single point of >control,
whereas all those in macro expansions get individual lines in control file.

I had this problem in an earlier version of RFC patch
where I called pr_debug from within drm_dev_dbg etc.

Re: [RESEND PATCH v6 14/14] drm/print: Add tracefs support to the drm logging helpers

2021-07-29 Thread jim . cromie 
On Wed, Jul 21, 2021 at 11:56 AM Sean Paul  wrote:
>
> From: Sean Paul 
>
> This patch adds a new module parameter called drm.trace which accepts
> the same mask as drm.debug. When a debug category is enabled, log
> messages will be put in a new tracefs instance called drm for
> consumption.
>
> Using the new tracefs instance will allow distros to enable drm logging
> in production without impacting performance or spamming the system
> logs.

hi Paul,

I should have started reading here, not at patch-1
While I still think some of the _syslog name changes are extra,
drm_debug_enabled() needs it - rename goes with narrower purpose.

a couple comments below, trimming heavily.


> +#define DEBUG_PARM_DESC(dst) \
> +"Enable debug output to " dst ", where each bit enables a debug category.\n" 
> \

I will be borrowing that idea.

> +
> +MODULE_PARM_DESC(debug, DEBUG_PARM_DESC("syslog"));
>  module_param_named(debug, __drm_debug_syslog, int, 0600);
>


> +void __drm_printfn_debug_syslog_and_trace(struct drm_printer *p,
> +  struct va_format *vaf)
> +{
> +   pr_debug("%s %pV", p->prefix, vaf);

Im not sure about prefixing this way.
dyndbg query needs to see the prefix in the format string at compile-time.

My RFC patch does the prefixing in the macro layer, when enabled.
when disabled, prefixing at runtime is fine.
This looks easy to shake out..
















> +   drm_trace_printf("%s %pV", p->prefix, vaf);
> +}
> +EXPORT_SYMBOL(__drm_printfn_debug_syslog_and_trace);
> +
>  void __drm_printfn_err(struct drm_printer *p, struct va_format *vaf)
>  {
> pr_err("*ERROR* %s %pV", p->prefix, vaf);
> @@ -246,6 +278,14 @@ void drm_dev_printk(const struct device *dev, const char 
> *level,
> struct va_format vaf;
> va_list args;
>
> +   va_start(args, format);
> +   vaf.fmt = format;
> +   vaf.va = 
> +   drm_trace_printf("%s%s[" DRM_NAME ":%ps] %pV",
> +dev ? dev_name(dev) : "",dev ? " " : "",
> +__builtin_return_address(0), );
> +   va_end(args);
> +
> va_start(args, format);
> vaf.fmt = format;
> vaf.va = 

here and below, you re-prepare vaf.
can you just prepare once, and print 2x to different printers ?
or is that not allowed for some reason?

maybe macros to reduce linecount ?

 thanks
Jim

Re: [RESEND PATCH v6 14/14] drm/print: Add tracefs support to the drm logging helpers

2021-07-26 Thread Rodrigo Siqueira 
On 07/21, Sean Paul wrote:
> From: Sean Paul 
> 
> This patch adds a new module parameter called drm.trace which accepts
> the same mask as drm.debug. When a debug category is enabled, log
> messages will be put in a new tracefs instance called drm for
> consumption.
> 
> Using the new tracefs instance will allow distros to enable drm logging
> in production without impacting performance or spamming the system
> logs.
> 
> Cc: Daniel Vetter 
> Cc: David Airlie 
> Cc: Jani Nikula 
> Cc: Joonas Lahtinen 
> Cc: Pekka Paalanen 
> Cc: Rob Clark 
> Cc: Steven Rostedt 
> Cc: Thomas Zimmermann 
> Cc: Ville Syrjälä 
> Cc: Chris Wilson 
> Cc: Steven Rostedt 
> Reported-by: kernel test robot  # warning reported in v6
> Acked-by: Pekka Paalanen 
> Signed-off-by: Sean Paul 
> Link: 
> https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fpatchwork.freedesktop.org%2Fpatch%2Fmsgid%2F20191010204823.195540-1-sean%40poorly.rundata=04%7C01%7CRodrigo.Siqueira%40amd.com%7Cbb3d63341a974f70c29208d94c70e119%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637624869979178761%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000sdata=NEMZqbDJcEq%2B5Ext3F3%2BLkLNe7JHFa7HNWozh5boJ9M%3Dreserved=0
>  #v1
> Link: 
> https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Flists.freedesktop.org%2Farchives%2Fdri-devel%2F2019-November%2F243230.htmldata=04%7C01%7CRodrigo.Siqueira%40amd.com%7Cbb3d63341a974f70c29208d94c70e119%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637624869979178761%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000sdata=nA9bS%2BIsuMxcqdTzf9aClkl3ovccPVnInyFyBpDT8Do%3Dreserved=0
>  #v2
> Link: 
> https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fpatchwork.freedesktop.org%2Fpatch%2Fmsgid%2F20191212203301.142437-1-sean%40poorly.rundata=04%7C01%7CRodrigo.Siqueira%40amd.com%7Cbb3d63341a974f70c29208d94c70e119%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637624869979178761%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000sdata=Vz6I8SF%2BjoajAR48%2BzJmx6llQAHtww9VROLT4krkZK4%3Dreserved=0
>  #v3
> Link: 
> https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fpatchwork.freedesktop.org%2Fpatch%2Fmsgid%2F20200114172155.215463-1-sean%40poorly.rundata=04%7C01%7CRodrigo.Siqueira%40amd.com%7Cbb3d63341a974f70c29208d94c70e119%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637624869979178761%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000sdata=Vcjao5eEZEE6o1Q%2B8CyIalz0UTAiqydOxR8qISbh61I%3Dreserved=0
>  #v4
> Link: 
> https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fpatchwork.freedesktop.org%2Fpatch%2Fmsgid%2F20200608210505.48519-14-sean%40poorly.rundata=04%7C01%7CRodrigo.Siqueira%40amd.com%7Cbb3d63341a974f70c29208d94c70e119%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637624869979178761%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000sdata=rc1O7r2SQqR3I3Rn0bSRbS9mZBBH%2Fg7%2BEmGcLexheO0%3Dreserved=0
>  #v5
> Link: 
> https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fpatchwork.freedesktop.org%2Fpatch%2Fmsgid%2F20200818210510.49730-15-sean%40poorly.rundata=04%7C01%7CRodrigo.Siqueira%40amd.com%7Cbb3d63341a974f70c29208d94c70e119%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637624869979178761%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000sdata=PblinqQ5Y8NgHJKGZ%2BwUU7hIlZHwiy0SOsXhB7NPegw%3Dreserved=0
>  #v6
> 
> Changes in v5:
> -Re-write to use trace_array and the tracefs instance support
> Changes in v6:
> -Use the new trace_array_init_printk() to initialize global trace
>  buffers
> Changes in v6.5:
> -Fix kernel test robot warning
> -Add a trace printf in __drm_err
> ---
>  Documentation/gpu/drm-uapi.rst |   6 +
>  drivers/gpu/drm/drm_drv.c  |   3 +
>  drivers/gpu/drm/drm_print.c| 223 -
>  include/drm/drm_print.h|  63 --
>  4 files changed, 255 insertions(+), 40 deletions(-)
> 
> diff --git a/Documentation/gpu/drm-uapi.rst b/Documentation/gpu/drm-uapi.rst
> index 7e51dd40bf6e..ce1ea39fb4b9 100644
> --- a/Documentation/gpu/drm-uapi.rst
> +++ b/Documentation/gpu/drm-uapi.rst
> @@ -424,6 +424,12 @@ Debugfs Support
>  .. kernel-doc:: drivers/gpu/drm/drm_debugfs.c
> :export:
>  
> +DRM Tracing
> +---
> +
> +.. kernel-doc:: drivers/gpu/drm/drm_print.c
> +   :doc: DRM Tracing
> +
>  Sysfs Support
>  =
>  
> diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
> index 8804ec7d3215..71dc0b161b51 100644
> --- a/drivers/gpu/drm/drm_drv.c
> +++ b/drivers/gpu/drm/drm_drv.c
> @@ -1034,12 +1034,15 @@ static void drm_core_exit(void)
>   drm_sysfs_destroy();
>   idr_destroy(_minors_idr);
>   drm_connector_ida_destroy();
> + drm_trace_cleanup();
>  }
>  
>  static int __init

[RESEND PATCH v6 14/14] drm/print: Add tracefs support to the drm logging helpers

2021-07-21 Thread Sean Paul 
From: Sean Paul 

This patch adds a new module parameter called drm.trace which accepts
the same mask as drm.debug. When a debug category is enabled, log
messages will be put in a new tracefs instance called drm for
consumption.

Using the new tracefs instance will allow distros to enable drm logging
in production without impacting performance or spamming the system
logs.

Cc: Daniel Vetter 
Cc: David Airlie 
Cc: Jani Nikula 
Cc: Joonas Lahtinen 
Cc: Pekka Paalanen 
Cc: Rob Clark 
Cc: Steven Rostedt 
Cc: Thomas Zimmermann 
Cc: Ville Syrjälä 
Cc: Chris Wilson 
Cc: Steven Rostedt 
Reported-by: kernel test robot  # warning reported in v6
Acked-by: Pekka Paalanen 
Signed-off-by: Sean Paul 
Link: 
https://patchwork.freedesktop.org/patch/msgid/20191010204823.195540-1-s...@poorly.run
 #v1
Link: 
https://lists.freedesktop.org/archives/dri-devel/2019-November/243230.html #v2
Link: 
https://patchwork.freedesktop.org/patch/msgid/20191212203301.142437-1-s...@poorly.run
 #v3
Link: 
https://patchwork.freedesktop.org/patch/msgid/20200114172155.215463-1-s...@poorly.run
 #v4
Link: 
https://patchwork.freedesktop.org/patch/msgid/20200608210505.48519-14-s...@poorly.run
 #v5
Link: 
https://patchwork.freedesktop.org/patch/msgid/20200818210510.49730-15-s...@poorly.run
 #v6

Changes in v5:
-Re-write to use trace_array and the tracefs instance support
Changes in v6:
-Use the new trace_array_init_printk() to initialize global trace
 buffers
Changes in v6.5:
-Fix kernel test robot warning
-Add a trace printf in __drm_err
---
 Documentation/gpu/drm-uapi.rst |   6 +
 drivers/gpu/drm/drm_drv.c  |   3 +
 drivers/gpu/drm/drm_print.c| 223 -
 include/drm/drm_print.h|  63 --
 4 files changed, 255 insertions(+), 40 deletions(-)

diff --git a/Documentation/gpu/drm-uapi.rst b/Documentation/gpu/drm-uapi.rst
index 7e51dd40bf6e..ce1ea39fb4b9 100644
--- a/Documentation/gpu/drm-uapi.rst
+++ b/Documentation/gpu/drm-uapi.rst
@@ -424,6 +424,12 @@ Debugfs Support
 .. kernel-doc:: drivers/gpu/drm/drm_debugfs.c
:export:
 
+DRM Tracing
+---
+
+.. kernel-doc:: drivers/gpu/drm/drm_print.c
+   :doc: DRM Tracing
+
 Sysfs Support
 =
 
diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
index 8804ec7d3215..71dc0b161b51 100644
--- a/drivers/gpu/drm/drm_drv.c
+++ b/drivers/gpu/drm/drm_drv.c
@@ -1034,12 +1034,15 @@ static void drm_core_exit(void)
drm_sysfs_destroy();
idr_destroy(_minors_idr);
drm_connector_ida_destroy();
+   drm_trace_cleanup();
 }
 
 static int __init drm_core_init(void)
 {
int ret;
 
+   drm_trace_init();
+
drm_connector_ida_init();
idr_init(_minors_idr);
drm_memcpy_init_early();
diff --git a/drivers/gpu/drm/drm_print.c b/drivers/gpu/drm/drm_print.c
index 4d984a01b3a3..64d9a724c2df 100644
--- a/drivers/gpu/drm/drm_print.c
+++ b/drivers/gpu/drm/drm_print.c
@@ -31,6 +31,7 @@
 #include 
 #include 
 #include 
+#include 
 
 #include 
 #include 
@@ -43,17 +44,34 @@
 unsigned int __drm_debug_syslog;
 EXPORT_SYMBOL(__drm_debug_syslog);
 
-MODULE_PARM_DESC(debug, "Enable debug output, where each bit enables a debug 
category.\n"
-"\t\tBit 0 (0x01)  will enable CORE messages (drm core code)\n"
-"\t\tBit 1 (0x02)  will enable DRIVER messages (drm controller code)\n"
-"\t\tBit 2 (0x04)  will enable KMS messages (modesetting code)\n"
-"\t\tBit 3 (0x08)  will enable PRIME messages (prime code)\n"
-"\t\tBit 4 (0x10)  will enable ATOMIC messages (atomic code)\n"
-"\t\tBit 5 (0x20)  will enable VBL messages (vblank code)\n"
-"\t\tBit 7 (0x80)  will enable LEASE messages (leasing code)\n"
-"\t\tBit 8 (0x100) will enable DP messages (displayport code)");
+/*
+ * __drm_debug_trace: Enable debug output in drm tracing instance.
+ * Bitmask of DRM_UT_x. See include/drm/drm_print.h for details.
+ */
+unsigned int __drm_debug_trace;
+EXPORT_SYMBOL(__drm_debug_trace);
+
+#define DEBUG_PARM_DESC(dst) \
+"Enable debug output to " dst ", where each bit enables a debug category.\n" \
+"\t\tBit 0 (0x01)  will enable CORE messages (drm core code)\n" \
+"\t\tBit 1 (0x02)  will enable DRIVER messages (drm controller code)\n" \
+"\t\tBit 2 (0x04)  will enable KMS messages (modesetting code)\n" \
+"\t\tBit 3 (0x08)  will enable PRIME messages (prime code)\n" \
+"\t\tBit 4 (0x10)  will enable ATOMIC messages (atomic code)\n" \
+"\t\tBit 5 (0x20)  will enable VBL messages (vblank code)\n" \
+"\t\tBit 7 (0x80)  will enable LEASE messages (leasing code)\n" \
+"\t\tBit 8 (0x100) will enable DP messages (displayport code)"
+
+MODULE_PARM_DESC(debug, DEBUG_PARM_DESC("syslog"));
 module_param_named(debug, __drm_debug_syslog, int, 0600);
 
+MODULE_PARM_DESC(trace, DEBUG_PARM_DESC("tracefs"));
+module_param_named(trace, __drm_debug_trace, int, 0600);
+
+#ifdef CONFIG_TRACING
+struct trace_array *trace_arr;
+#endif
+
 void __drm_puts_coredump(struct drm_printer *p, const char *str)
 {
struct drm_print_iterator *iterator =

Re: [PATCH v6 14/14] drm/print: Add tracefs support to the drm logging helpers

2020-08-18 Thread kernel test robot 
Hi Sean,

I love your patch! Perhaps something to improve:

[auto build test WARNING on drm-intel/for-linux-next]
[also build test WARNING on tegra-drm/drm/tegra/for-next drm-tip/drm-tip 
linus/master drm-exynos/exynos-drm-next v5.9-rc1 next-20200818]
[cannot apply to drm/drm-next]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:
https://github.com/0day-ci/linux/commits/Sean-Paul/drm-trace-Mirror-DRM-debug-logs-to-tracefs/20200819-050745
base:   git://anongit.freedesktop.org/drm-intel for-linux-next
config: openrisc-randconfig-s031-20200818 (attached as .config)
compiler: or1k-linux-gcc (GCC) 9.3.0
reproduce:
wget 
https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O 
~/bin/make.cross
chmod +x ~/bin/make.cross
# apt-get install sparse
# sparse version: v0.6.2-183-gaa6ede3b-dirty
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross C=1 
CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=openrisc 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot 


sparse warnings: (new ones prefixed by >>)

>> drivers/gpu/drm/drm_print.c:459:21: sparse: sparse: non-ANSI function 
>> declaration of function 'drm_trace_init'
>> drivers/gpu/drm/drm_print.c:498:24: sparse: sparse: non-ANSI function 
>> declaration of function 'drm_trace_cleanup'
   drivers/gpu/drm/drm_print.c:467:15: sparse: sparse: undefined identifier 
'trace_array_init_printk'
   drivers/gpu/drm/drm_print.c: note: in included file (through 
arch/openrisc/include/asm/io.h, include/linux/io.h):
   include/asm-generic/io.h:179:15: sparse: sparse: cast to restricted __le32
   include/asm-generic/io.h:179:15: sparse: sparse: cast to restricted __le32
   include/asm-generic/io.h:179:15: sparse: sparse: cast to restricted __le32
   include/asm-generic/io.h:179:15: sparse: sparse: cast to restricted __le32
   include/asm-generic/io.h:179:15: sparse: sparse: cast to restricted __le32
   include/asm-generic/io.h:179:15: sparse: sparse: cast to restricted __le32

# 
https://github.com/0day-ci/linux/commit/fe0a955028a2121ce9ab9acd1c2ab74d219cdc60
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review 
Sean-Paul/drm-trace-Mirror-DRM-debug-logs-to-tracefs/20200819-050745
git checkout fe0a955028a2121ce9ab9acd1c2ab74d219cdc60
vim +/drm_trace_init +459 drivers/gpu/drm/drm_print.c

   452  
   453  /**
   454   * drm_trace_init - initializes the drm trace array
   455   *
   456   * This function fetches (or creates) the drm trace array. This should 
be called
   457   * once on drm subsystem creation and matched with drm_trace_cleanup().
   458   */
 > 459  void drm_trace_init()
   460  {
   461  int ret;
   462  
   463  trace_arr = trace_array_get_by_name("drm");
   464  if (!trace_arr)
   465  return;
   466  
   467  ret = trace_array_init_printk(trace_arr);
   468  if (ret)
   469  drm_trace_cleanup();
   470  }
   471  EXPORT_SYMBOL(drm_trace_init);
   472  
   473  /**
   474   * drm_trace_printf - adds an entry to the drm tracefs instance
   475   * @format: printf format of the message to add to the trace
   476   *
   477   * This function adds a new entry in the drm tracefs instance
   478   */
   479  void drm_trace_printf(const char *format, ...)
   480  {
   481  struct va_format vaf;
   482  va_list args;
   483  
   484  va_start(args, format);
   485  vaf.fmt = format;
   486  vaf.va = 
   487  trace_array_printk(trace_arr, _THIS_IP_, "%pV", );
   488  va_end(args);
   489  }
   490  
   491  /**
   492   * drm_trace_cleanup - destroys the drm trace array
   493   *
   494   * This function destroys the drm trace array created with 
drm_trace_init. This
   495   * should be called once on drm subsystem close and matched with
   496   * drm_trace_init().
   497   */
 > 498  void drm_trace_cleanup()

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-...@lists.01.org


.config.gz
Description: application/gzip
___
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

[PATCH v6 14/14] drm/print: Add tracefs support to the drm logging helpers

2020-08-18 Thread Sean Paul 
From: Sean Paul 

This patch adds a new module parameter called drm.trace which accepts
the same mask as drm.debug. When a debug category is enabled, log
messages will be put in a new tracefs instance called drm for
consumption.

Using the new tracefs instance will allow distros to enable drm logging
in production without impacting performance or spamming the system
logs.

Cc: Daniel Vetter 
Cc: David Airlie 
Cc: Jani Nikula 
Cc: Joonas Lahtinen 
Cc: Pekka Paalanen 
Cc: Rob Clark 
Cc: Steven Rostedt 
Cc: Thomas Zimmermann 
Cc: Ville Syrjälä 
Cc: Chris Wilson 
Cc: Steven Rostedt 
Acked-by: Pekka Paalanen 
Signed-off-by: Sean Paul 
Link: 
https://patchwork.freedesktop.org/patch/msgid/20191010204823.195540-1-s...@poorly.run
 #v1
Link: 
https://lists.freedesktop.org/archives/dri-devel/2019-November/243230.html #v2
Link: 
https://patchwork.freedesktop.org/patch/msgid/20191212203301.142437-1-s...@poorly.run
 #v3
Link: 
https://patchwork.freedesktop.org/patch/msgid/20200114172155.215463-1-s...@poorly.run
 #v4
Link: 
https://patchwork.freedesktop.org/patch/msgid/20200608210505.48519-14-s...@poorly.run
 #v5

Changes in v5:
-Re-write to use trace_array and the tracefs instance support
Changes in v6:
-Use the new trace_array_init_printk() to initialize global trace
 buffers
---
 Documentation/gpu/drm-uapi.rst |   6 +
 drivers/gpu/drm/drm_drv.c  |   3 +
 drivers/gpu/drm/drm_print.c| 216 -
 include/drm/drm_print.h|  63 --
 4 files changed, 248 insertions(+), 40 deletions(-)

diff --git a/Documentation/gpu/drm-uapi.rst b/Documentation/gpu/drm-uapi.rst
index 7dce175f6d75..0297ff71f8f8 100644
--- a/Documentation/gpu/drm-uapi.rst
+++ b/Documentation/gpu/drm-uapi.rst
@@ -424,6 +424,12 @@ Debugfs Support
 .. kernel-doc:: drivers/gpu/drm/drm_debugfs.c
:export:
 
+DRM Tracing
+---
+
+.. kernel-doc:: drivers/gpu/drm/drm_print.c
+   :doc: DRM Tracing
+
 Sysfs Support
 =
 
diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
index 13068fdf4331..555b40580497 100644
--- a/drivers/gpu/drm/drm_drv.c
+++ b/drivers/gpu/drm/drm_drv.c
@@ -1107,12 +1107,15 @@ static void drm_core_exit(void)
drm_sysfs_destroy();
idr_destroy(_minors_idr);
drm_connector_ida_destroy();
+   drm_trace_cleanup();
 }
 
 static int __init drm_core_init(void)
 {
int ret;
 
+   drm_trace_init();
+
drm_connector_ida_init();
idr_init(_minors_idr);
 
diff --git a/drivers/gpu/drm/drm_print.c b/drivers/gpu/drm/drm_print.c
index 4d984a01b3a3..6b11143d1ab2 100644
--- a/drivers/gpu/drm/drm_print.c
+++ b/drivers/gpu/drm/drm_print.c
@@ -31,6 +31,7 @@
 #include 
 #include 
 #include 
+#include 
 
 #include 
 #include 
@@ -43,17 +44,34 @@
 unsigned int __drm_debug_syslog;
 EXPORT_SYMBOL(__drm_debug_syslog);
 
-MODULE_PARM_DESC(debug, "Enable debug output, where each bit enables a debug 
category.\n"
-"\t\tBit 0 (0x01)  will enable CORE messages (drm core code)\n"
-"\t\tBit 1 (0x02)  will enable DRIVER messages (drm controller code)\n"
-"\t\tBit 2 (0x04)  will enable KMS messages (modesetting code)\n"
-"\t\tBit 3 (0x08)  will enable PRIME messages (prime code)\n"
-"\t\tBit 4 (0x10)  will enable ATOMIC messages (atomic code)\n"
-"\t\tBit 5 (0x20)  will enable VBL messages (vblank code)\n"
-"\t\tBit 7 (0x80)  will enable LEASE messages (leasing code)\n"
-"\t\tBit 8 (0x100) will enable DP messages (displayport code)");
+/*
+ * __drm_debug_trace: Enable debug output in drm tracing instance.
+ * Bitmask of DRM_UT_x. See include/drm/drm_print.h for details.
+ */
+unsigned int __drm_debug_trace;
+EXPORT_SYMBOL(__drm_debug_trace);
+
+#define DEBUG_PARM_DESC(dst) \
+"Enable debug output to " dst ", where each bit enables a debug category.\n" \
+"\t\tBit 0 (0x01)  will enable CORE messages (drm core code)\n" \
+"\t\tBit 1 (0x02)  will enable DRIVER messages (drm controller code)\n" \
+"\t\tBit 2 (0x04)  will enable KMS messages (modesetting code)\n" \
+"\t\tBit 3 (0x08)  will enable PRIME messages (prime code)\n" \
+"\t\tBit 4 (0x10)  will enable ATOMIC messages (atomic code)\n" \
+"\t\tBit 5 (0x20)  will enable VBL messages (vblank code)\n" \
+"\t\tBit 7 (0x80)  will enable LEASE messages (leasing code)\n" \
+"\t\tBit 8 (0x100) will enable DP messages (displayport code)"
+
+MODULE_PARM_DESC(debug, DEBUG_PARM_DESC("syslog"));
 module_param_named(debug, __drm_debug_syslog, int, 0600);
 
+MODULE_PARM_DESC(trace, DEBUG_PARM_DESC("tracefs"));
+module_param_named(trace, __drm_debug_trace, int, 0600);
+
+#ifdef CONFIG_TRACING
+struct trace_array *trace_arr;
+#endif
+
 void __drm_puts_coredump(struct drm_printer *p, const char *str)
 {
struct drm_print_iterator *iterator = p->arg;
@@ -166,6 +184,20 @@ void __drm_printfn_debug_syslog(struct drm_printer *p, 
struct va_format *vaf)
 }
 EXPORT_SYMBOL(__drm_printfn_debug_syslog);
 
+void __drm_printfn_trace(struct drm_printer *p, struct va_format *vaf)
+{
+   drm_trace_printf("%s %pV",