[PATCH] venus: Add support for SSR trigger using fault injection

[PATCH] venus: Add support for SSR trigger using fault injection

[Dikshita Agarwal]

Here we introduce a new fault injection for SSR trigger.

To trigger the SSR:
 echo 100 > /sys/kernel/debug/venus/fail_ssr/probability
 echo 1 > /sys/kernel/debug/venus/fail_ssr/times

signed-off-by: Dikshita Agarwal <quic_dikshita@quicinc.com>
Signed-off-by: Stanimir Varbanov <stanimir.varbanov@linaro.org>
---
 drivers/media/platform/qcom/venus/core.c  | 15 ++++++++++++++-
 drivers/media/platform/qcom/venus/dbgfs.c | 18 ++++++++++++++++++
 drivers/media/platform/qcom/venus/dbgfs.h |  1 +
 3 files changed, 33 insertions(+), 1 deletion(-)

diff --git a/drivers/media/platform/qcom/venus/core.c b/drivers/media/platform/qcom/venus/core.c
index 877eca1..abfa5d6 100644
--- a/drivers/media/platform/qcom/venus/core.c
+++ b/drivers/media/platform/qcom/venus/core.c
@@ -265,6 +265,19 @@ static void venus_assign_register_offsets(struct venus_core *core)
 	}
 }
 
+static irqreturn_t venus_isr_thread(int irq, void *dev_id)
+{
+	struct venus_core *core = dev_id;
+	irqreturn_t ret;
+
+	ret = hfi_isr_thread(irq, dev_id);
+
+	if (ret == IRQ_HANDLED && venus_fault_inject_ssr())
+		hfi_core_trigger_ssr(core, HFI_TEST_SSR_SW_ERR_FATAL);
+
+	return ret;
+}
+
 static int venus_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
@@ -320,7 +333,7 @@ static int venus_probe(struct platform_device *pdev)
 	INIT_DELAYED_WORK(&core->work, venus_sys_error_handler);
 	init_waitqueue_head(&core->sys_err_done);
 
-	ret = devm_request_threaded_irq(dev, core->irq, hfi_isr, hfi_isr_thread,
+	ret = devm_request_threaded_irq(dev, core->irq, hfi_isr, venus_isr_thread,
 					IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
 					"venus", core);
 	if (ret)
diff --git a/drivers/media/platform/qcom/venus/dbgfs.c b/drivers/media/platform/qcom/venus/dbgfs.c
index 52de47f..a0bfb9e 100644
--- a/drivers/media/platform/qcom/venus/dbgfs.c
+++ b/drivers/media/platform/qcom/venus/dbgfs.c
@@ -4,13 +4,31 @@
  */
 
 #include <linux/debugfs.h>
+#include <linux/fault-inject.h>
 
 #include "core.h"
 
+#ifdef CONFIG_FAULT_INJECTION
+static DECLARE_FAULT_ATTR(venus_ssr_attr);
+#endif
+
+bool venus_fault_inject_ssr(void)
+{
+#ifdef CONFIG_FAULT_INJECTION
+	return should_fail(&venus_ssr_attr, 1);
+#else
+	return false;
+#endif
+}
+
 void venus_dbgfs_init(struct venus_core *core)
 {
 	core->root = debugfs_create_dir("venus", NULL);
 	debugfs_create_x32("fw_level", 0644, core->root, &venus_fw_debug);
+
+#ifdef CONFIG_FAULT_INJECTION
+	fault_create_debugfs_attr("fail_ssr", core->root, &venus_ssr_attr);
+#endif
 }
 
 void venus_dbgfs_deinit(struct venus_core *core)
diff --git a/drivers/media/platform/qcom/venus/dbgfs.h b/drivers/media/platform/qcom/venus/dbgfs.h
index b7b621a..b0d0686 100644
--- a/drivers/media/platform/qcom/venus/dbgfs.h
+++ b/drivers/media/platform/qcom/venus/dbgfs.h
@@ -8,5 +8,6 @@ struct venus_core;
 
 void venus_dbgfs_init(struct venus_core *core);
 void venus_dbgfs_deinit(struct venus_core *core);
+bool venus_fault_inject_ssr(void);
 
 #endif
-- 
2.7.4

Re: [PATCH] venus: Add support for SSR trigger using fault injection

[Stephen Boyd]

Quoting Dikshita Agarwal (2022-06-09 04:52:46)
> diff --git a/drivers/media/platform/qcom/venus/dbgfs.c b/drivers/media/platform/qcom/venus/dbgfs.c
> index 52de47f..a0bfb9e 100644
> --- a/drivers/media/platform/qcom/venus/dbgfs.c
> +++ b/drivers/media/platform/qcom/venus/dbgfs.c
> @@ -4,13 +4,31 @@
>   */
>
>  #include <linux/debugfs.h>
> +#include <linux/fault-inject.h>
>
>  #include "core.h"
>
> +#ifdef CONFIG_FAULT_INJECTION
> +static DECLARE_FAULT_ATTR(venus_ssr_attr);
> +#endif
> +
> +bool venus_fault_inject_ssr(void)
> +{
> +#ifdef CONFIG_FAULT_INJECTION
> +       return should_fail(&venus_ssr_attr, 1);
> +#else
> +       return false;
> +#endif
> +}

It would be better to remove the ifdef in this function and define a
static inline version that returns false when CONFIG_FAULT_INJECTION is
disabled so that the compiler doesn't have to insert a function call to
venus_fault_inject_ssr() when the config is disabled. It may also be
good to avoid the jump when enabled by exporting the attribute to the
irq handler file.

> +
>  void venus_dbgfs_init(struct venus_core *core)
>  {
>         core->root = debugfs_create_dir("venus", NULL);
>         debugfs_create_x32("fw_level", 0644, core->root, &venus_fw_debug);
> +
> +#ifdef CONFIG_FAULT_INJECTION
> +       fault_create_debugfs_attr("fail_ssr", core->root, &venus_ssr_attr);
> +#endif
>  }
>
>  void venus_dbgfs_deinit(struct venus_core *core)