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pigweed/pigweed/pigweed/10a055aad301f46cbe5fbe8f79e56d6a4ff71f4d
commit
10a055aad301f46cbe5fbe8f79e56d6a4ff71f4d
[log]
author
Joshua Liebow-Feeser <joshlf@google.com>
Tue Jul 08 10:04:22 2025 -0700
committer
CQ Bot Account <pigweed-scoped@luci-project-accounts.iam.gserviceaccount.com>
Tue Jul 08 10:04:22 2025 -0700
tree
b849382680d9ea6fca01f943d27a281437e0ebed
parent
86a6be4ca0dc91c01a042183d2fed185de04619c [diff]
pw_kernel: Store stacks in .bss to save space

This change saves ~4,000 bytes from the kernel ELF file. In particular,
here are the outputs of `bazelisk build --config k_host
//pw_kernel/tooling:code_size` from before and after this change:

Before
======
bazel-out/darwin_x86_64-opt/bin/pw_kernel/target/mps2_an505/kernel_only_demo,17652
bazel-out/darwin_x86_64-opt/bin/pw_kernel/target/mps2_an505/userspace_demo,14532
bazel-out/darwin_x86_64-opt/bin/pw_kernel/target/qemu_virt_riscv32/kernel_only_demo,16684
bazel-out/darwin_x86_64-opt/bin/pw_kernel/target/qemu_virt_riscv32/userspace_demo,13128

After
=====
bazel-out/darwin_x86_64-opt/bin/pw_kernel/target/mps2_an505/kernel_only_demo,13548
bazel-out/darwin_x86_64-opt/bin/pw_kernel/target/mps2_an505/userspace_demo,10432
bazel-out/darwin_x86_64-opt/bin/pw_kernel/target/qemu_virt_riscv32/kernel_only_demo,12624
bazel-out/darwin_x86_64-opt/bin/pw_kernel/target/qemu_virt_riscv32/userspace_demo,9080

Change-Id: Ie93cfc52215753e1b4482d5fe3058dc53fcfa86a
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/303372
Commit-Queue: Joshua Liebow-Feeser <joshlf@google.com>
Lint: Lint 🤖 <android-build-ayeaye@system.gserviceaccount.com>
Pigweed-Auto-Submit: Joshua Liebow-Feeser <joshlf@google.com>
Docs-Not-Needed: Joshua Liebow-Feeser <joshlf@google.com>
Presubmit-Verified: CQ Bot Account <pigweed-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Erik Gilling <konkers@google.com>
10 files changed
tree: b849382680d9ea6fca01f943d27a281437e0ebed
  1. .allstar/
  2. .gemini/
  3. .github/
  4. .vscode/
  5. build_overrides/
  6. docker/
  7. docs/
  8. kudzu/
  9. pw_alignment/
  10. pw_allocator/
  11. pw_analog/
  12. pw_android_toolchain/
  13. pw_arduino_build/
  14. pw_assert/
  15. pw_assert_basic/
  16. pw_assert_fuchsia/
  17. pw_assert_log/
  18. pw_assert_tokenized/
  19. pw_assert_trap/
  20. pw_assert_zephyr/
  21. pw_async/
  22. pw_async2/
  23. pw_async2_basic/
  24. pw_async2_epoll/
  25. pw_async_basic/
  26. pw_async_fuchsia/
  27. pw_atomic/
  28. pw_base64/
  29. pw_bloat/
  30. pw_blob_store/
  31. pw_bluetooth/
  32. pw_bluetooth_hci/
  33. pw_bluetooth_profiles/
  34. pw_bluetooth_proxy/
  35. pw_bluetooth_sapphire/
  36. pw_boot/
  37. pw_boot_cortex_m/
  38. pw_build/
  39. pw_build_android/
  40. pw_build_info/
  41. pw_build_mcuxpresso/
  42. pw_bytes/
  43. pw_channel/
  44. pw_checksum/
  45. pw_chre/
  46. pw_chrono/
  47. pw_chrono_embos/
  48. pw_chrono_freertos/
  49. pw_chrono_rp2040/
  50. pw_chrono_stl/
  51. pw_chrono_threadx/
  52. pw_chrono_zephyr/
  53. pw_cli/
  54. pw_cli_analytics/
  55. pw_clock_tree/
  56. pw_clock_tree_mcuxpresso/
  57. pw_compilation_testing/
  58. pw_config_loader/
  59. pw_console/
  60. pw_containers/
  61. pw_cpu_exception/
  62. pw_cpu_exception_cortex_m/
  63. pw_cpu_exception_risc_v/
  64. pw_crypto/
  65. pw_digital_io/
  66. pw_digital_io_linux/
  67. pw_digital_io_mcuxpresso/
  68. pw_digital_io_rp2040/
  69. pw_digital_io_zephyr/
  70. pw_display/
  71. pw_dma_mcuxpresso/
  72. pw_docgen/
  73. pw_doctor/
  74. pw_elf/
  75. pw_emu/
  76. pw_env_setup/
  77. pw_env_setup_zephyr/
  78. pw_file/
  79. pw_flatbuffers/
  80. pw_format/
  81. pw_function/
  82. pw_fuzzer/
  83. pw_grpc/
  84. pw_hdlc/
  85. pw_hex_dump/
  86. pw_i2c/
  87. pw_i2c_linux/
  88. pw_i2c_mcuxpresso/
  89. pw_i2c_rp2040/
  90. pw_i2c_zephyr/
  91. pw_ide/
  92. pw_interrupt/
  93. pw_interrupt_cortex_m/
  94. pw_interrupt_freertos/
  95. pw_interrupt_zephyr/
  96. pw_intrusive_ptr/
  97. pw_json/
  98. pw_kernel/
  99. pw_kvs/
  100. pw_libc/
  101. pw_libcxx/
  102. pw_log/
  103. pw_log_android/
  104. pw_log_basic/
  105. pw_log_fuchsia/
  106. pw_log_null/
  107. pw_log_rpc/
  108. pw_log_string/
  109. pw_log_tokenized/
  110. pw_log_zephyr/
  111. pw_malloc/
  112. pw_malloc_freelist/
  113. pw_malloc_freertos/
  114. pw_metric/
  115. pw_minimal_cpp_stdlib/
  116. pw_module/
  117. pw_multibuf/
  118. pw_multisink/
  119. pw_numeric/
  120. pw_package/
  121. pw_perf_test/
  122. pw_persistent_ram/
  123. pw_polyfill/
  124. pw_preprocessor/
  125. pw_presubmit/
  126. pw_protobuf/
  127. pw_protobuf_compiler/
  128. pw_random/
  129. pw_random_fuchsia/
  130. pw_result/
  131. pw_ring_buffer/
  132. pw_router/
  133. pw_rpc/
  134. pw_rpc_transport/
  135. pw_rust/
  136. pw_sensor/
  137. pw_snapshot/
  138. pw_software_update/
  139. pw_span/
  140. pw_spi/
  141. pw_spi_linux/
  142. pw_spi_mcuxpresso/
  143. pw_spi_rp2040/
  144. pw_status/
  145. pw_stm32cube_build/
  146. pw_stream/
  147. pw_stream_shmem_mcuxpresso/
  148. pw_stream_uart_linux/
  149. pw_stream_uart_mcuxpresso/
  150. pw_string/
  151. pw_symbolizer/
  152. pw_sync/
  153. pw_sync_baremetal/
  154. pw_sync_embos/
  155. pw_sync_freertos/
  156. pw_sync_stl/
  157. pw_sync_threadx/
  158. pw_sync_zephyr/
  159. pw_sys_io/
  160. pw_sys_io_ambiq_sdk/
  161. pw_sys_io_arduino/
  162. pw_sys_io_baremetal_lm3s6965evb/
  163. pw_sys_io_baremetal_stm32f429/
  164. pw_sys_io_emcraft_sf2/
  165. pw_sys_io_mcuxpresso/
  166. pw_sys_io_rp2040/
  167. pw_sys_io_stdio/
  168. pw_sys_io_stm32cube/
  169. pw_sys_io_zephyr/
  170. pw_system/
  171. pw_target_runner/
  172. pw_thread/
  173. pw_thread_embos/
  174. pw_thread_freertos/
  175. pw_thread_stl/
  176. pw_thread_threadx/
  177. pw_thread_zephyr/
  178. pw_tls_client/
  179. pw_tls_client_boringssl/
  180. pw_tls_client_mbedtls/
  181. pw_tokenizer/
  182. pw_toolchain/
  183. pw_trace/
  184. pw_trace_tokenized/
  185. pw_transfer/
  186. pw_uart/
  187. pw_uart_mcuxpresso/
  188. pw_unit_test/
  189. pw_uuid/
  190. pw_varint/
  191. pw_watch/
  192. pw_web/
  193. pw_work_queue/
  194. seed/
  195. targets/
  196. third_party/
  197. ts/
  198. zephyr/
  199. .dockerignore ⇨ .gitignore
  200. activate.fish ⇨ bootstrap.fish
  201. activate.sh ⇨ bootstrap.sh
  202. .bazelignore
  203. .bazelrc
  204. .bazelversion
  205. .black.toml
  206. .clang-format
  207. .clang-tidy
  208. .eslintrc.cjs
  209. .git-blame-ignore-revs
  210. .gitattributes
  211. .gitignore
  212. .gn
  213. .mypy.ini
  214. .prettierignore
  215. .prettierrc.cjs
  216. .pw_ide.yaml
  217. .pylintrc
  218. .ruff.toml
  219. activate.bat
  220. Android.bp
  221. AUTHORS
  222. bootstrap.bat
  223. bootstrap.fish
  224. bootstrap.sh
  225. BUILD.bazel
  226. BUILD.gn
  227. BUILDCONFIG.gn
  228. CMakeLists.txt
  229. GEMINI.md
  230. go.mod
  231. go.sum
  232. jest.config.ts
  233. Kconfig.zephyr
  234. LICENSE
  235. MODULE.bazel
  236. MODULE.bazel.lock
  237. modules.gni
  238. OWNERS
  239. package-lock.json
  240. package.json
  241. pigweed.json
  242. PIGWEED_MODULES
  243. pnpm-lock.yaml
  244. README.md
  245. REPO.bazel
  246. rollup-protos.config.js
  247. rollup.config.js
  248. tsconfig.json
  249. WORKSPACE
  250. WORKSPACE_OWNERS
README.md

Pigweed

Pigweed is an open source collection of embedded-targeted libraries–or as we like to call them, modules. These modules are building blocks and infrastructure that enable faster and more reliable development on small-footprint MMU-less 32-bit microcontrollers like the STMicroelectronics STM32L452 or the Nordic nRF52832.

For more information please see our website: https://pigweed.dev/.

Links