| Message ID | 20210903182839.1.I20856983f2841b78936134dcf9cdf6ecafe632b9@changeid (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | coresight: cpu-debug: control default behavior via Kconfig | expand |
On Fri, Sep 03, 2021 at 06:28:54PM -0700, Brian Norris wrote: > Debugfs is nice and so are module parameters, but > * debugfs doesn't take effect early (e.g., if drivers are locking up > before user space gets anywhere) > * module parameters either add a lot to the kernel command line, or > else take effect late as well (if you build =m and configure in > /etc/modprobe.d/) > > So in the same spirit as these > CONFIG_PANIC_ON_OOPS (also available via cmdline or modparam) > CONFIG_INTEL_IOMMU_DEFAULT_ON (also available via cmdline) > add a new Kconfig option. > > Module parameters and debugfs can still override. > > Signed-off-by: Brian Norris <briannorris@chromium.org> Thanks for the patch, looks good to me: Reviewed-by: Leo Yan <leo.yan@linaro.org> > --- > > drivers/hwtracing/coresight/Kconfig | 13 +++++++++++++ > drivers/hwtracing/coresight/coresight-cpu-debug.c | 2 +- > 2 files changed, 14 insertions(+), 1 deletion(-) > > diff --git a/drivers/hwtracing/coresight/Kconfig b/drivers/hwtracing/coresight/Kconfig > index f026e5c0e777..8b638eb3cb7d 100644 > --- a/drivers/hwtracing/coresight/Kconfig > +++ b/drivers/hwtracing/coresight/Kconfig > @@ -150,6 +150,19 @@ config CORESIGHT_CPU_DEBUG > To compile this driver as a module, choose M here: the > module will be called coresight-cpu-debug. > > +config CORESIGHT_CPU_DEBUG_DEFAULT_ON > + bool "Enable CoreSight CPU Debug by default > + depends on CORESIGHT_CPU_DEBUG > + help > + Say Y here to enable the CoreSight Debug panic-debug by default. This > + can also be enabled via debugfs, but this ensures the debug feature > + is enabled as early as possible. > + > + Has the same effect as setting coresight_cpu_debug.enable=1 on the > + kernel command line. > + > + Say N if unsure. > + > config CORESIGHT_CTI > tristate "CoreSight Cross Trigger Interface (CTI) driver" > depends on ARM || ARM64 > diff --git a/drivers/hwtracing/coresight/coresight-cpu-debug.c b/drivers/hwtracing/coresight/coresight-cpu-debug.c > index 00de46565bc4..8845ec4b4402 100644 > --- a/drivers/hwtracing/coresight/coresight-cpu-debug.c > +++ b/drivers/hwtracing/coresight/coresight-cpu-debug.c > @@ -105,7 +105,7 @@ static DEFINE_PER_CPU(struct debug_drvdata *, debug_drvdata); > static int debug_count; > static struct dentry *debug_debugfs_dir; > > -static bool debug_enable; > +static bool debug_enable = IS_ENABLED(CONFIG_CORESIGHT_CPU_DEBUG_DEFAULT_ON); > module_param_named(enable, debug_enable, bool, 0600); > MODULE_PARM_DESC(enable, "Control to enable coresight CPU debug functionality"); > > -- > 2.33.0.153.gba50c8fa24-goog >
Hi Brian, On Fri, Sep 03, 2021 at 06:28:54PM -0700, Brian Norris wrote: > Debugfs is nice and so are module parameters, but > * debugfs doesn't take effect early (e.g., if drivers are locking up > before user space gets anywhere) > * module parameters either add a lot to the kernel command line, or > else take effect late as well (if you build =m and configure in > /etc/modprobe.d/) > > So in the same spirit as these > CONFIG_PANIC_ON_OOPS (also available via cmdline or modparam) > CONFIG_INTEL_IOMMU_DEFAULT_ON (also available via cmdline) > add a new Kconfig option. > > Module parameters and debugfs can still override. > > Signed-off-by: Brian Norris <briannorris@chromium.org> > --- > > drivers/hwtracing/coresight/Kconfig | 13 +++++++++++++ > drivers/hwtracing/coresight/coresight-cpu-debug.c | 2 +- > 2 files changed, 14 insertions(+), 1 deletion(-) > I have applied this patch to my local tree. I will make that tree public when next week when 5.15-rc1 has been released. Thanks, Mathieu > diff --git a/drivers/hwtracing/coresight/Kconfig b/drivers/hwtracing/coresight/Kconfig > index f026e5c0e777..8b638eb3cb7d 100644 > --- a/drivers/hwtracing/coresight/Kconfig > +++ b/drivers/hwtracing/coresight/Kconfig > @@ -150,6 +150,19 @@ config CORESIGHT_CPU_DEBUG > To compile this driver as a module, choose M here: the > module will be called coresight-cpu-debug. > > +config CORESIGHT_CPU_DEBUG_DEFAULT_ON > + bool "Enable CoreSight CPU Debug by default > + depends on CORESIGHT_CPU_DEBUG > + help > + Say Y here to enable the CoreSight Debug panic-debug by default. This > + can also be enabled via debugfs, but this ensures the debug feature > + is enabled as early as possible. > + > + Has the same effect as setting coresight_cpu_debug.enable=1 on the > + kernel command line. > + > + Say N if unsure. > + > config CORESIGHT_CTI > tristate "CoreSight Cross Trigger Interface (CTI) driver" > depends on ARM || ARM64 > diff --git a/drivers/hwtracing/coresight/coresight-cpu-debug.c b/drivers/hwtracing/coresight/coresight-cpu-debug.c > index 00de46565bc4..8845ec4b4402 100644 > --- a/drivers/hwtracing/coresight/coresight-cpu-debug.c > +++ b/drivers/hwtracing/coresight/coresight-cpu-debug.c > @@ -105,7 +105,7 @@ static DEFINE_PER_CPU(struct debug_drvdata *, debug_drvdata); > static int debug_count; > static struct dentry *debug_debugfs_dir; > > -static bool debug_enable; > +static bool debug_enable = IS_ENABLED(CONFIG_CORESIGHT_CPU_DEBUG_DEFAULT_ON); > module_param_named(enable, debug_enable, bool, 0600); > MODULE_PARM_DESC(enable, "Control to enable coresight CPU debug functionality"); > > -- > 2.33.0.153.gba50c8fa24-goog >
On Fri, Sep 3, 2021 at 6:29 PM Brian Norris <briannorris@chromium.org> wrote: > --- a/drivers/hwtracing/coresight/Kconfig > +++ b/drivers/hwtracing/coresight/Kconfig > @@ -150,6 +150,19 @@ config CORESIGHT_CPU_DEBUG > +config CORESIGHT_CPU_DEBUG_DEFAULT_ON > + bool "Enable CoreSight CPU Debug by default ^^ Eek, I failed to terminate this string, and kbuild is even warning about it: drivers/hwtracing/coresight/Kconfig:145:warning: multi-line strings not supported Sorry about that; I can submit a v2 if you'd like, or feel free to fix up my mistake when you apply it. Sorry, Brian
On Wed, Sep 15, 2021 at 4:41 PM Brian Norris <briannorris@chromium.org> wrote: > > On Fri, Sep 3, 2021 at 6:29 PM Brian Norris <briannorris@chromium.org> wrote: > > --- a/drivers/hwtracing/coresight/Kconfig > > +++ b/drivers/hwtracing/coresight/Kconfig > > @@ -150,6 +150,19 @@ config CORESIGHT_CPU_DEBUG > > > +config CORESIGHT_CPU_DEBUG_DEFAULT_ON > > + bool "Enable CoreSight CPU Debug by default > > ^^ Eek, I failed to terminate this string, and kbuild is even warning about it: > > drivers/hwtracing/coresight/Kconfig:145:warning: multi-line strings > not supported > > Sorry about that; I can submit a v2 if you'd like, or feel free to fix > up my mistake when you apply it. And I see you already fixed it -- should've checked before posting: https://git.kernel.org/pub/scm/linux/kernel/git/coresight/linux.git/commit/?id=616ac6902c982f03da9d0b1e4f845df0980d055d [Fixed missing double quote in Kconfig title] Thanks, Brian
diff --git a/drivers/hwtracing/coresight/Kconfig b/drivers/hwtracing/coresight/Kconfig index f026e5c0e777..8b638eb3cb7d 100644 --- a/drivers/hwtracing/coresight/Kconfig +++ b/drivers/hwtracing/coresight/Kconfig @@ -150,6 +150,19 @@ config CORESIGHT_CPU_DEBUG To compile this driver as a module, choose M here: the module will be called coresight-cpu-debug. +config CORESIGHT_CPU_DEBUG_DEFAULT_ON + bool "Enable CoreSight CPU Debug by default + depends on CORESIGHT_CPU_DEBUG + help + Say Y here to enable the CoreSight Debug panic-debug by default. This + can also be enabled via debugfs, but this ensures the debug feature + is enabled as early as possible. + + Has the same effect as setting coresight_cpu_debug.enable=1 on the + kernel command line. + + Say N if unsure. + config CORESIGHT_CTI tristate "CoreSight Cross Trigger Interface (CTI) driver" depends on ARM || ARM64 diff --git a/drivers/hwtracing/coresight/coresight-cpu-debug.c b/drivers/hwtracing/coresight/coresight-cpu-debug.c index 00de46565bc4..8845ec4b4402 100644 --- a/drivers/hwtracing/coresight/coresight-cpu-debug.c +++ b/drivers/hwtracing/coresight/coresight-cpu-debug.c @@ -105,7 +105,7 @@ static DEFINE_PER_CPU(struct debug_drvdata *, debug_drvdata); static int debug_count; static struct dentry *debug_debugfs_dir; -static bool debug_enable; +static bool debug_enable = IS_ENABLED(CONFIG_CORESIGHT_CPU_DEBUG_DEFAULT_ON); module_param_named(enable, debug_enable, bool, 0600); MODULE_PARM_DESC(enable, "Control to enable coresight CPU debug functionality");
Debugfs is nice and so are module parameters, but * debugfs doesn't take effect early (e.g., if drivers are locking up before user space gets anywhere) * module parameters either add a lot to the kernel command line, or else take effect late as well (if you build =m and configure in /etc/modprobe.d/) So in the same spirit as these CONFIG_PANIC_ON_OOPS (also available via cmdline or modparam) CONFIG_INTEL_IOMMU_DEFAULT_ON (also available via cmdline) add a new Kconfig option. Module parameters and debugfs can still override. Signed-off-by: Brian Norris <briannorris@chromium.org> --- drivers/hwtracing/coresight/Kconfig | 13 +++++++++++++ drivers/hwtracing/coresight/coresight-cpu-debug.c | 2 +- 2 files changed, 14 insertions(+), 1 deletion(-)