Re: [PATCH v4 2/4] drm/amdgpu: Rework coredump to use memory dynamically

From: Shashank Sharma
Date: Thu Aug 17 2023 - 02:42:19 EST

Hello Andre,

On 15/08/2023 21:50, André Almeida wrote:
Instead of storing coredump information inside amdgpu_device struct,
move if to a proper separated struct and allocate it dynamically. This
will make it easier to further expand the logged information.

Signed-off-by: André Almeida <andrealmeid@xxxxxxxxxx>
---
v4: change kmalloc to kzalloc
---
drivers/gpu/drm/amd/amdgpu/amdgpu.h | 14 +++--
drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 63 ++++++++++++++--------
2 files changed, 49 insertions(+), 28 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
index 9c6a332261ab..0d560b713948 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
@@ -1088,11 +1088,6 @@ struct amdgpu_device {
uint32_t *reset_dump_reg_list;
uint32_t *reset_dump_reg_value;
int num_regs;
-#ifdef CONFIG_DEV_COREDUMP
- struct amdgpu_task_info reset_task_info;
- bool reset_vram_lost;
- struct timespec64 reset_time;
-#endif
bool scpm_enabled;
uint32_t scpm_status;
@@ -1105,6 +1100,15 @@ struct amdgpu_device {
uint32_t aid_mask;
};
+#ifdef CONFIG_DEV_COREDUMP
+struct amdgpu_coredump_info {
+ struct amdgpu_device *adev;
+ struct amdgpu_task_info reset_task_info;
+ struct timespec64 reset_time;
+ bool reset_vram_lost;
+};

The patch looks good to me in general, but I would recommend slightly different arrangement and segregation of GPU reset information.

Please consider a higher level structure adev->gpu_reset_info, and move everything related to reset dump info into that, including this new coredump_info structure, something like this:

struct amdgpu_reset_info {

    uint32_t *reset_dump_reg_list;

    uint32_t *reset_dump_reg_value;

    int num_regs;

#ifdef CONFIG_DEV_COREDUMP

   struct amdgpu_coredump_info *coredump_info;/* keep this dynamic allocation */

#endif

}


This will make sure that all the relevant information is at the same place.

- Shashank

+#endif
+
static inline struct amdgpu_device *drm_to_adev(struct drm_device *ddev)
{
return container_of(ddev, struct amdgpu_device, ddev);
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
index bf4781551f88..b5b879bcc5c9 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
@@ -4799,12 +4799,17 @@ static int amdgpu_reset_reg_dumps(struct amdgpu_device *adev)
return 0;
}
-#ifdef CONFIG_DEV_COREDUMP
+#ifndef CONFIG_DEV_COREDUMP
+static void amdgpu_coredump(struct amdgpu_device *adev, bool vram_lost,
+ struct amdgpu_reset_context *reset_context)
+{
+}
+#else
static ssize_t amdgpu_devcoredump_read(char *buffer, loff_t offset,
size_t count, void *data, size_t datalen)
{
struct drm_printer p;
- struct amdgpu_device *adev = data;
+ struct amdgpu_coredump_info *coredump = data;
struct drm_print_iterator iter;
int i;
@@ -4818,21 +4823,21 @@ static ssize_t amdgpu_devcoredump_read(char *buffer, loff_t offset,
drm_printf(&p, "**** AMDGPU Device Coredump ****\n");
drm_printf(&p, "kernel: " UTS_RELEASE "\n");
drm_printf(&p, "module: " KBUILD_MODNAME "\n");
- drm_printf(&p, "time: %lld.%09ld\n", adev->reset_time.tv_sec, adev->reset_time.tv_nsec);
- if (adev->reset_task_info.pid)
+ drm_printf(&p, "time: %lld.%09ld\n", coredump->reset_time.tv_sec, coredump->reset_time.tv_nsec);
+ if (coredump->reset_task_info.pid)
drm_printf(&p, "process_name: %s PID: %d\n",
- adev->reset_task_info.process_name,
- adev->reset_task_info.pid);
+ coredump->reset_task_info.process_name,
+ coredump->reset_task_info.pid);
- if (adev->reset_vram_lost)
+ if (coredump->reset_vram_lost)
drm_printf(&p, "VRAM is lost due to GPU reset!\n");
- if (adev->num_regs) {
+ if (coredump->adev->num_regs) {
drm_printf(&p, "AMDGPU register dumps:\nOffset: Value:\n");
- for (i = 0; i < adev->num_regs; i++)
+ for (i = 0; i < coredump->adev->num_regs; i++)
drm_printf(&p, "0x%08x: 0x%08x\n",
- adev->reset_dump_reg_list[i],
- adev->reset_dump_reg_value[i]);
+ coredump->adev->reset_dump_reg_list[i],
+ coredump->adev->reset_dump_reg_value[i]);
}
return count - iter.remain;
@@ -4840,14 +4845,32 @@ static ssize_t amdgpu_devcoredump_read(char *buffer, loff_t offset,
static void amdgpu_devcoredump_free(void *data)
{
+ kfree(data);
}
-static void amdgpu_reset_capture_coredumpm(struct amdgpu_device *adev)
+static void amdgpu_coredump(struct amdgpu_device *adev, bool vram_lost,
+ struct amdgpu_reset_context *reset_context)
{
+ struct amdgpu_coredump_info *coredump;
struct drm_device *dev = adev_to_drm(adev);
- ktime_get_ts64(&adev->reset_time);
- dev_coredumpm(dev->dev, THIS_MODULE, adev, 0, GFP_NOWAIT,
+ coredump = kzalloc(sizeof(*coredump), GFP_NOWAIT);
+
+ if (!coredump) {
+ DRM_ERROR("%s: failed to allocate memory for coredump\n", __func__);
+ return;
+ }
+
+ coredump->reset_vram_lost = vram_lost;
+
+ if (reset_context->job && reset_context->job->vm)
+ coredump->reset_task_info = reset_context->job->vm->task_info;
+
+ coredump->adev = adev;
+
+ ktime_get_ts64(&coredump->reset_time);
+
+ dev_coredumpm(dev->dev, THIS_MODULE, coredump, 0, GFP_NOWAIT,
amdgpu_devcoredump_read, amdgpu_devcoredump_free);
}
#endif
@@ -4955,15 +4978,9 @@ int amdgpu_do_asic_reset(struct list_head *device_list_handle,
goto out;
vram_lost = amdgpu_device_check_vram_lost(tmp_adev);
-#ifdef CONFIG_DEV_COREDUMP
- tmp_adev->reset_vram_lost = vram_lost;
- memset(&tmp_adev->reset_task_info, 0,
- sizeof(tmp_adev->reset_task_info));
- if (reset_context->job && reset_context->job->vm)
- tmp_adev->reset_task_info =
- reset_context->job->vm->task_info;
- amdgpu_reset_capture_coredumpm(tmp_adev);
-#endif
+
+ amdgpu_coredump(tmp_adev, vram_lost, reset_context);
+
if (vram_lost) {
DRM_INFO("VRAM is lost due to GPU reset!\n");
amdgpu_inc_vram_lost(tmp_adev);