freedreno: add fd_rd_output facilities for gzip-compressed RD dumps

Provide fd_rd_output facilities which enable constructing RD dumps that are
stored into gzip-compressed output. This matches the default behavior of
libwrap. Enabling and adjusting the behavior of functionality is done
through the FD_RD_DUMP environment variable.

Integration into Turnip's MSM backend is covered, replacing the previous
RD dump that was enabled through TU_DEBUG=rd. That debug option still
works and is the same as using FD_RD_DUMP=enable.

By default the dumps are created for each submission, using the provided
submit index. FD_RD_DUMP=combine enables gathering dumps for submissions
for the given logical device into a single file.

In the Turnip integration, FD_RD_DUMP=full will force dumping contents of
any buffer object. Additionally, with that option enabled any previous
submit will be waited on.

Specifying FD_RD_DUMP=trigger sets up a trigger file that can be used to
activate dumping manually. Writing zero or some non-integer value to the
file will disable dumping. Writing a positive integer value to it will
enable dumps for that many future submissions. Writing -1 to it will enable
dumps until disabled.

Signed-off-by: Zan Dobersek <zdobersek@igalia.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/27230>

docs/drivers/freedreno.rst

@@ -369,9 +369,8 @@ Command Stream Capture
 ^^^^^^^^^^^^^^^^^^^^^^
 
 During Mesa development, it's often useful to look at the command streams we
-send to the kernel.  Mesa itself doesn't implement a way to stream them out
-(though it maybe should!).  Instead, we have an interface for the kernel to
-capture all submitted command streams:
+send to the kernel.  We have an interface for the kernel to capture all
+submitted command streams:
 
 .. code-block:: sh
 
@@ -391,6 +390,28 @@ probably want to cause a crash in the GPU during a frame of interest so that a
 single GPU core dump is generated.  Emitting ``0xdeadbeef`` in the CS should be
 enough to cause a fault.
 
+``fd_rd_output`` facilities provide support for generating the command stream
+capture from inside Mesa. Different ``FD_RD_DUMP`` options are available:
+
+- ``enable`` simply enables dumping the command stream on each submit for a
+  given logical device. When a more advanced option is specified, ``enable`` is
+  implied as specified.
+- ``combine`` will combine all dumps into a single file instead of writing the
+  dump for each submit into a standalone file.
+- ``full`` will dump every buffer object, which is necessary for replays of
+  command streams (see below).
+- ``trigger`` will establish a trigger file through which dumps can be better
+  controlled. Writing a positive integer value into the file will enable dumping
+  of that many subsequent submits. Writing -1 will enable dumping of submits
+  until disabled. Writing 0 (or any other value) will disable dumps.
+
+Output dump files and trigger file (when enabled) are hard-coded to be placed
+under ``/tmp``, or ``/data/local/tmp`` under Android.
+
+Functionality is generic to any Freedreno-based backend, but is currently only
+integrated in the MSM backend of Turnip. Using the existing ``TU_DEBUG=rd``
+option will translate to ``FD_RD_DUMP=enable``.
+
 Capturing Hang RD
 +++++++++++++++++
 

src/freedreno/common/freedreno_rd_output.c

@@ -0,0 +1,250 @@
+/*
+ * Copyright © 2024 Igalia S.L.
+ * SPDX-License-Identifier: MIT
+ */
+
+#include "freedreno_rd_output.h"
+
+#include <assert.h>
+#include <ctype.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+#include "c11/threads.h"
+#include "util/log.h"
+#include "util/u_atomic.h"
+#include "util/u_debug.h"
+
+#ifdef ANDROID
+static const char *fd_rd_output_base_path = "/data/local/tmp";
+#else
+static const char *fd_rd_output_base_path = "/tmp";
+#endif
+
+static const struct debug_control fd_rd_dump_options[] = {
+   { "enable", FD_RD_DUMP_ENABLE },
+   { "combine", FD_RD_DUMP_COMBINE },
+   { "full", FD_RD_DUMP_FULL },
+   { "trigger", FD_RD_DUMP_TRIGGER },
+   { NULL, 0 }
+};
+
+struct fd_rd_dump_env fd_rd_dump_env;
+
+static void
+fd_rd_dump_env_init_once(void)
+{
+   fd_rd_dump_env.flags = parse_debug_string(os_get_option("FD_RD_DUMP"),
+                                             fd_rd_dump_options);
+
+   /* If any of the more-detailed FD_RD_DUMP flags is enabled, the general
+    * FD_RD_DUMP_ENABLE flag should also implicitly be set.
+    */
+   if (fd_rd_dump_env.flags & ~FD_RD_DUMP_ENABLE)
+      fd_rd_dump_env.flags |= FD_RD_DUMP_ENABLE;
+}
+
+void
+fd_rd_dump_env_init(void)
+{
+   static once_flag once = ONCE_FLAG_INIT;
+   call_once(&once, fd_rd_dump_env_init_once);
+}
+
+static void
+fd_rd_output_sanitize_name(char *name)
+{
+   /* The name string is null-terminated after being constructed via snprintf.
+    * Sanitize it by reducing to an underscore anything that's not a hyphen,
+    * underscore, dot or alphanumeric character.
+    */
+   for (char *s = name; *s; ++s) {
+      if (isalnum(*s) || *s == '-' || *s == '_' || *s == '.')
+         continue;
+      *s = '_';
+   }
+}
+
+void
+fd_rd_output_init(struct fd_rd_output *output, char* output_name)
+{
+   snprintf(output->name, sizeof(output->name), "%s", output_name);
+   fd_rd_output_sanitize_name(output->name);
+
+   output->combine = false;
+   output->file = NULL;
+   output->trigger_fd = -1;
+   output->trigger_count = 0;
+
+   if (FD_RD_DUMP(COMBINE)) {
+      output->combine = true;
+
+      char file_path[256];
+      snprintf(file_path, sizeof(file_path), "%s/%s_combined.rd",
+               fd_rd_output_base_path, output->name);
+      output->file = gzopen(file_path, "w");
+   }
+
+   if (FD_RD_DUMP(TRIGGER)) {
+      char file_path[256];
+      snprintf(file_path, sizeof(file_path), "%s/%s_trigger",
+               fd_rd_output_base_path, output->name);
+      output->trigger_fd = open(file_path, O_RDWR | O_CREAT | O_TRUNC, 0600);
+   }
+}
+
+void
+fd_rd_output_fini(struct fd_rd_output *output)
+{
+   if (output->file != NULL) {
+      assert(output->combine);
+      gzclose(output->file);
+   }
+
+   if (output->trigger_fd >= 0) {
+      close(output->trigger_fd);
+
+      /* Remove the trigger file. The filename is reconstructed here
+       * instead of having to spend memory to store it in the struct.
+       */
+      char file_path[256];
+      snprintf(file_path, sizeof(file_path), "%s/%s_trigger",
+               fd_rd_output_base_path, output->name);
+      unlink(file_path);
+   }
+}
+
+static void
+fd_rd_output_update_trigger_count(struct fd_rd_output *output)
+{
+   assert(FD_RD_DUMP(TRIGGER));
+
+   /* Retrieve the trigger file size, only attempt to update the trigger
+    * value if anything was actually written to that file.
+    */
+   struct stat stat;
+   if (fstat(output->trigger_fd, &stat) != 0) {
+      mesa_loge("[fd_rd_output] failed to acccess the %s trigger file",
+                output->name);
+      return;
+   }
+
+   if (stat.st_size == 0)
+      return;
+
+   char trigger_data[32];
+   int ret = read(output->trigger_fd, trigger_data, sizeof(trigger_data));
+   if (ret < 0) {
+      mesa_loge("[fd_rd_output] failed to read from the %s trigger file",
+                output->name);
+      return;
+   }
+   int num_read = MIN2(ret, sizeof(trigger_data) - 1);
+
+   /* After reading from it, the trigger file should be reset, which means
+    * moving the file offset to the start of the file as well as truncating
+    * it to zero bytes.
+    */
+   if (lseek(output->trigger_fd, 0, SEEK_SET) < 0) {
+      mesa_loge("[fd_rd_output] failed to reset the %s trigger file position",
+                output->name);
+      return;
+   }
+
+   if (ftruncate(output->trigger_fd, 0) < 0) {
+      mesa_loge("[fd_rd_output] failed to truncate the %s trigger file",
+                output->name);
+      return;
+   }
+
+   /* Try to decode the count value through strtol. -1 translates to UINT_MAX
+    * and keeps generating dumps until disabled. Any positive value will
+    * allow generating dumps for that many submits. Any other value will
+    * disable any further generation of RD dumps.
+    */
+   trigger_data[num_read] = '\0';
+   int32_t value = strtol(trigger_data, NULL, 0);
+
+   if (value == -1) {
+      output->trigger_count = UINT_MAX;
+      mesa_logi("[fd_rd_output] %s trigger enabling RD dumps until disabled",
+                output->name);
+   } else if (value > 0) {
+      output->trigger_count = (uint32_t) value;
+      mesa_logi("[fd_rd_output] %s trigger enabling RD dumps for next %u submissions",
+                output->name, output->trigger_count);
+   } else {
+      output->trigger_count = 0;
+      mesa_logi("[fd_rd_output] %s trigger disabling RD dumps", output->name);
+   }
+}
+
+bool
+fd_rd_output_begin(struct fd_rd_output *output, uint32_t submit_idx)
+{
+   assert(output->combine ^ (output->file == NULL));
+
+   if (FD_RD_DUMP(TRIGGER)) {
+      fd_rd_output_update_trigger_count(output);
+
+      if (output->trigger_count == 0)
+         return false;
+      /* UINT_MAX corresponds to generating dumps until disabled. */
+      if (output->trigger_count != UINT_MAX)
+          --output->trigger_count;
+   }
+
+   if (output->combine)
+      return true;
+
+   char file_path[256];
+   snprintf(file_path, sizeof(file_path), "%s/%s_%.5d.rd",
+            fd_rd_output_base_path, output->name, submit_idx);
+   output->file = gzopen(file_path, "w");
+   return true;
+}
+
+static void
+fd_rd_output_write(struct fd_rd_output *output, const void *buffer, int size)
+{
+   const uint8_t *pos = (uint8_t *) buffer;
+   while (size > 0) {
+      int ret = gzwrite(output->file, pos, size);
+      if (ret < 0) {
+         mesa_loge("[fd_rd_output] failed to write to compressed output: %s",
+                   gzerror(output->file, NULL));
+         return;
+      }
+      pos += ret;
+      size -= ret;
+   }
+}
+
+void
+fd_rd_output_write_section(struct fd_rd_output *output, enum rd_sect_type type,
+                           const void *buffer, int size)
+{
+   fd_rd_output_write(output, &type, 4);
+   fd_rd_output_write(output, &size, 4);
+   fd_rd_output_write(output, buffer, size);
+}
+
+void
+fd_rd_output_end(struct fd_rd_output *output)
+{
+   assert(output->file != NULL);
+
+   /* When combining output, flush the gzip stream on each submit. This should
+    * store all the data before any problem during the submit itself occurs.
+    */
+   if (output->combine) {
+      gzflush(output->file, Z_FINISH);
+      return;
+   }
+
+   gzclose(output->file);
+   output->file = NULL;
+}

src/freedreno/common/freedreno_rd_output.h

@@ -0,0 +1,66 @@
+/*
+ * Copyright © 2024 Igalia S.L.
+ * SPDX-License-Identifier: MIT
+ */
+
+#ifndef __FREEDRENO_RD_OUTPUT_H__
+#define __FREEDRENO_RD_OUTPUT_H__
+
+#include <stdbool.h>
+#include <stdint.h>
+#include <zlib.h>
+
+#include "redump.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+enum fd_rd_dump_flags {
+   FD_RD_DUMP_ENABLE = 1 << 0,
+   FD_RD_DUMP_COMBINE = 1 << 1,
+   FD_RD_DUMP_FULL = 1 << 2,
+   FD_RD_DUMP_TRIGGER = 1 << 3,
+};
+
+struct fd_rd_dump_env {
+   uint32_t flags;
+};
+
+extern struct fd_rd_dump_env fd_rd_dump_env;
+
+#define FD_RD_DUMP(name) unlikely(fd_rd_dump_env.flags & FD_RD_DUMP_##name)
+
+void
+fd_rd_dump_env_init(void);
+
+struct fd_rd_output {
+   char name[128];
+   bool combine;
+   gzFile file;
+
+   int trigger_fd;
+   uint32_t trigger_count;
+};
+
+void
+fd_rd_output_init(struct fd_rd_output *output, char* output_name);
+
+void
+fd_rd_output_fini(struct fd_rd_output *output);
+
+bool
+fd_rd_output_begin(struct fd_rd_output *output, uint32_t submit_idx);
+
+void
+fd_rd_output_write_section(struct fd_rd_output *output, enum rd_sect_type type,
+                           const void *buffer, int size);
+
+void
+fd_rd_output_end(struct fd_rd_output *output);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __FREEDRENO_RD_OUTPUT_H__ */

src/freedreno/common/meson.build

@@ -38,6 +38,8 @@ libfreedreno_common = static_library(
     'freedreno_dev_info.c',
     'freedreno_dev_info.h',
     'freedreno_pm4.h',
+    'freedreno_rd_output.c',
+    'freedreno_rd_output.h',
     'freedreno_uuid.c',
     'freedreno_uuid.h',
     'freedreno_guardband.h',

src/freedreno/vulkan/tu_device.cc

@@ -21,6 +21,7 @@
 #include "util/hex.h"
 #include "util/driconf.h"
 #include "util/os_misc.h"
+#include "util/u_process.h"
 #include "vk_shader_module.h"
 #include "vk_sampler.h"
 #include "vk_util.h"
@@ -2219,6 +2220,7 @@ tu_CreateDevice(VkPhysicalDevice physicalDevice,
 
    device->instance = physical_device->instance;
    device->physical_device = physical_device;
+   device->device_idx = device->physical_device->device_count++;
 
    result = tu_drm_device_init(device);
    if (result != VK_SUCCESS) {
@@ -2492,6 +2494,26 @@ tu_CreateDevice(VkPhysicalDevice physicalDevice,
 
    tu_breadcrumbs_init(device);
 
+   if (FD_RD_DUMP(ENABLE)) {
+      struct vk_app_info *app_info = &device->instance->vk.app_info;
+      const char *app_name_str = app_info->app_name ?
+         app_info->app_name : util_get_process_name();
+      const char *engine_name_str = app_info->engine_name ?
+         app_info->engine_name : "unknown-engine";
+
+      char app_name[64];
+      snprintf(app_name, sizeof(app_name), "%s", app_name_str);
+
+      char engine_name[32];
+      snprintf(engine_name, sizeof(engine_name), "%s", engine_name_str);
+
+      char output_name[128];
+      snprintf(output_name, sizeof(output_name), "tu_%s.%s_device%u",
+               app_name, engine_name, device->device_idx);
+
+      fd_rd_output_init(&device->rd_output, output_name);
+   }
+
    *pDevice = tu_device_to_handle(device);
    return VK_SUCCESS;
 
@@ -2547,6 +2569,9 @@ tu_DestroyDevice(VkDevice _device, const VkAllocationCallbacks *pAllocator)
    if (!device)
       return;
 
+   if (FD_RD_DUMP(ENABLE))
+      fd_rd_output_fini(&device->rd_output);
+
    tu_breadcrumbs_finish(device);
 
    u_trace_context_fini(&device->trace_context);

src/freedreno/vulkan/tu_device.h

@@ -20,6 +20,7 @@
 #include "tu_suballoc.h"
 #include "tu_util.h"
 
+#include "common/freedreno_rd_output.h"
 #include "util/vma.h"
 #include "util/u_vector.h"
 
@@ -123,6 +124,8 @@ struct tu_physical_device
    struct vk_sync_type syncobj_type;
    struct vk_sync_timeline_type timeline_type;
    const struct vk_sync_type *sync_types[3];
+
+   uint32_t device_count;
 };
 VK_DEFINE_HANDLE_CASTS(tu_physical_device, vk.base, VkPhysicalDevice,
                        VK_OBJECT_TYPE_PHYSICAL_DEVICE)
@@ -253,6 +256,7 @@ struct tu_device
    int queue_count[TU_MAX_QUEUE_FAMILIES];
 
    struct tu_physical_device *physical_device;
+   uint32_t device_idx;
    int fd;
 
    struct ir3_compiler *compiler;
@@ -397,6 +401,8 @@ struct tu_device
 
    bool use_z24uint_s8uint;
    bool use_lrz;
+
+   struct fd_rd_output rd_output;
 };
 VK_DEFINE_HANDLE_CASTS(tu_device, vk.base, VkDevice, VK_OBJECT_TYPE_DEVICE)
 

src/freedreno/vulkan/tu_knl_drm_msm.cc

@@ -867,7 +867,7 @@ tu_queue_build_msm_gem_submit_cmds(struct tu_queue *queue,
 static VkResult
 tu_queue_submit_locked(struct tu_queue *queue, struct tu_queue_submit *submit)
 {
-   queue->device->submit_count++;
+   uint32_t submit_idx = queue->device->submit_count++;
 
    struct tu_cs *autotune_cs = NULL;
    if (submit->autotune_fence) {
@@ -910,16 +910,20 @@ tu_queue_submit_locked(struct tu_queue *queue, struct tu_queue_submit *submit)
       .syncobj_stride = sizeof(struct drm_msm_gem_submit_syncobj),
    };
 
-   if (TU_DEBUG(RD)) {
+   if (FD_RD_DUMP(ENABLE) && fd_rd_output_begin(&queue->device->rd_output, submit_idx)) {
       struct tu_device *device = queue->device;
-      static uint32_t submit_idx;
-      char path[32];
-      sprintf(path, "%.5d.rd", p_atomic_inc_return(&submit_idx));
-      int rd = open(path, O_CLOEXEC | O_WRONLY | O_CREAT | O_TRUNC, 0777);
-      if (rd >= 0) {
-         rd_write_section(rd, RD_CHIP_ID, &device->physical_device->dev_id.chip_id, 4);
+      struct fd_rd_output *rd_output = &device->rd_output;
 
-         rd_write_section(rd, RD_CMD, "tu-dump", 8);
+      if (FD_RD_DUMP(FULL)) {
+         VkResult result = tu_wait_fence(device, queue->msm_queue_id, queue->fence, ~0);
+         if (result != VK_SUCCESS) {
+            mesa_loge("FD_RD_DUMP_FULL: wait on previous submission for device %u and queue %d failed: %u",
+                      device->device_idx, queue->msm_queue_id, 0);
+         }
+      }
+
+      fd_rd_output_write_section(rd_output, RD_CHIP_ID, &device->physical_device->dev_id.chip_id, 4);
+      fd_rd_output_write_section(rd_output, RD_CMD, "tu-dump", 8);
 
       for (unsigned i = 0; i < device->bo_count; i++) {
          struct drm_msm_gem_submit_bo bo = device->bo_list[i];
@@ -927,10 +931,10 @@ tu_queue_submit_locked(struct tu_queue *queue, struct tu_queue_submit *submit)
          uint64_t iova = bo.presumed;
 
          uint32_t buf[3] = { iova, tu_bo->size, iova >> 32 };
-            rd_write_section(rd, RD_GPUADDR, buf, 12);
-            if (bo.flags & MSM_SUBMIT_BO_DUMP) {
+         fd_rd_output_write_section(rd_output, RD_GPUADDR, buf, 12);
+         if (bo.flags & MSM_SUBMIT_BO_DUMP || FD_RD_DUMP(FULL)) {
             msm_bo_map(device, tu_bo); /* note: this would need locking to be safe */
-               rd_write_section(rd, RD_BUFFER_CONTENTS, tu_bo->map, tu_bo->size);
+            fd_rd_output_write_section(rd_output, RD_BUFFER_CONTENTS, tu_bo->map, tu_bo->size);
          }
       }
 
@@ -939,10 +943,10 @@ tu_queue_submit_locked(struct tu_queue *queue, struct tu_queue_submit *submit)
          uint64_t iova = device->bo_list[cmd->submit_idx].presumed + cmd->submit_offset;
          uint32_t size = cmd->size >> 2;
          uint32_t buf[3] = { iova, size, iova >> 32 };
-            rd_write_section(rd, RD_CMDSTREAM_ADDR, buf, 12);
-         }
-         close(rd);
+         fd_rd_output_write_section(rd_output, RD_CMDSTREAM_ADDR, buf, 12);
       }
+
+      fd_rd_output_end(rd_output);
    }
 
    int ret = drmCommandWriteRead(queue->device->fd,

src/freedreno/vulkan/tu_util.cc

@@ -8,6 +8,7 @@
 #include <errno.h>
 #include <stdarg.h>
 
+#include "common/freedreno_rd_output.h"
 #include "util/u_math.h"
 #include "util/timespec.h"
 #include "vk_enum_to_str.h"
@@ -54,11 +55,19 @@ tu_env_init_once(void)
 
    if (TU_DEBUG(STARTUP))
       mesa_logi("TU_DEBUG=0x%x", tu_env.debug);
+
+   /* TU_DEBUG=rd functionality was moved to fd_rd_output. This debug option
+    * should translate to the basic-level FD_RD_DUMP_ENABLE option.
+    */
+   if (TU_DEBUG(RD))
+      fd_rd_dump_env.flags |= FD_RD_DUMP_ENABLE;
 }
 
 void
 tu_env_init(void)
 {
+   fd_rd_dump_env_init();
+
    static once_flag once = ONCE_FLAG_INIT;
    call_once(&once, tu_env_init_once);
 }