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GitWeb","url":"/gitweb?p\u003dlttng-ust.git;a\u003dcommit;h\u003d9c96e34c54f6e2beda872953c4d5955967c9fef4"}]}],"author":{"name":"Mathieu Desnoyers","email":"mathieu.desnoyers@efficios.com","date":"2023-02-02 15:25:57.000000000","tz":-300},"committer":{"name":"Mathieu Desnoyers","email":"mathieu.desnoyers@efficios.com","date":"2023-02-02 16:20:11.000000000","tz":-300},"subject":"Fix: use unaligned pointer accesses for lttng_inline_memcpy","message":"Fix: use unaligned pointer accesses for lttng_inline_memcpy\n\nlttng_inline_memcpy receives pointers which can be unaligned. This\ncauses issues (traps) specifically on arm 32-bit with 8-byte strings\n(including \\0).\n\nUse unaligned pointer accesses for loads/stores within\nlttng_inline_memcpy instead.\n\nThere is an impact on code generation on some architectures.  Using the\nfollowing test code on godbolt.org:\n\nvoid copy16_aligned(void *dest, void *src) {\n    *(uint16_t *)dest \u003d *(uint16_t *) src;\n}\n\nvoid copy16_unaligned(void *dest, void *src) {\n    STORE_UNALIGNED_INT(uint16_t, dest, LOAD_UNALIGNED_INT(uint16_t, src));\n}\n\nvoid copy32_aligned(void *dest, void *src) {\n    *(uint32_t *)dest \u003d *(uint32_t *) src;\n}\n\nvoid copy32_unaligned(void *dest, void *src) {\n    STORE_UNALIGNED_INT(uint32_t, dest, LOAD_UNALIGNED_INT(uint32_t, src));\n}\n\nvoid copy64_aligned(void *dest, void *src) {\n    *(uint64_t *)dest \u003d *(uint64_t *) src;\n}\n\nvoid copy64_unaligned(void *dest, void *src) {\n    STORE_UNALIGNED_INT(uint64_t, dest, LOAD_UNALIGNED_INT(uint64_t, src));\n}\n\nThe resulting assembler (gcc 12.2.0 in -O2) between aligned and\nunaligned:\n\n- x86-32: unchanged.\n- x86-64: unchanged.\n- powerpc32: unchanged.\n- powerpc64: unchanged.\n- arm32: 16 and 32-bit copy: unchanged. Added code for 64-bit unaligned copy.\n- aarch64: unchanged.\n- mips32: added code for unaligned.\n- mips64: added code for unaligned.\n- riscv: added code for unaligned.\n\nIf we want to improve the situation on mips and riscv, this would\nrequire introducing a new \"lttng_inline_integer_copy\" and expose\nadditional ring buffer client APIs in addition to event_write() which\ntake integers as inputs. Let\u0027s not introduce that complexity yet until\nit is justified.\n\nSigned-off-by: Mathieu Desnoyers \u003cmathieu.desnoyers@efficios.com\u003e\nChange-Id: I1e6471d4607ac6aff89f16ef24d5370e804b7612\n","web_links":[{"name":"gitweb","tooltip":"Open in GitWeb","url":"/gitweb?p\u003dlttng-ust.git;a\u003dcommit;h\u003d06edf3c5b1697e9724b1362ac89447b7d4928e87"}],"resolve_conflicts_web_links":[{"name":"gitweb","tooltip":"Open in GitWeb","url":"/gitweb?p\u003dlttng-ust.git;a\u003dcommit;h\u003d06edf3c5b1697e9724b1362ac89447b7d4928e87"}]},"branch":"refs/heads/master"},"7670fe5d3f8877e324aea77cfd8bea8e72ced950":{"kind":"REWORK","_number":2,"created":"2023-02-06 16:33:28.000000000","uploader":{"_account_id":1000009,"name":"Mathieu Desnoyers","email":"mathieu.desnoyers@efficios.com","username":"compudj","avatars":[{"url":"https://www.gravatar.com/avatar/7326b3e1d32b971a5e69d9730228c428.jpg?d\u003dretro\u0026r\u003dr\u0026s\u003d32","height":32},{"url":"https://www.gravatar.com/avatar/7326b3e1d32b971a5e69d9730228c428.jpg?d\u003dretro\u0026r\u003dr\u0026s\u003d56","height":56},{"url":"https://www.gravatar.com/avatar/7326b3e1d32b971a5e69d9730228c428.jpg?d\u003dretro\u0026r\u003dr\u0026s\u003d100","height":100},{"url":"https://www.gravatar.com/avatar/7326b3e1d32b971a5e69d9730228c428.jpg?d\u003dretro\u0026r\u003dr\u0026s\u003d120","height":120}]},"ref":"refs/changes/13/9413/2","fetch":{"anonymous http":{"url":"https://review.lttng.org/lttng-ust","ref":"refs/changes/13/9413/2","commands":{"Branch":"git fetch https://review.lttng.org/lttng-ust refs/changes/13/9413/2 \u0026\u0026 git checkout -b change-9413 FETCH_HEAD","Checkout":"git fetch https://review.lttng.org/lttng-ust refs/changes/13/9413/2 \u0026\u0026 git checkout FETCH_HEAD","Cherry Pick":"git fetch https://review.lttng.org/lttng-ust refs/changes/13/9413/2 \u0026\u0026 git cherry-pick FETCH_HEAD","Format Patch":"git fetch https://review.lttng.org/lttng-ust refs/changes/13/9413/2 \u0026\u0026 git format-patch -1 --stdout FETCH_HEAD","Pull":"git pull https://review.lttng.org/lttng-ust refs/changes/13/9413/2","Reset To":"git fetch https://review.lttng.org/lttng-ust refs/changes/13/9413/2 \u0026\u0026 git reset --hard FETCH_HEAD"}}},"commit":{"parents":[{"commit":"9c96e34c54f6e2beda872953c4d5955967c9fef4","subject":"ust-ctl: allow runtime version checks","web_links":[{"name":"gitweb","tooltip":"Open in GitWeb","url":"/gitweb?p\u003dlttng-ust.git;a\u003dcommit;h\u003d9c96e34c54f6e2beda872953c4d5955967c9fef4"}]}],"author":{"name":"Mathieu Desnoyers","email":"mathieu.desnoyers@efficios.com","date":"2023-02-02 15:25:57.000000000","tz":-300},"committer":{"name":"Mathieu Desnoyers","email":"mathieu.desnoyers@efficios.com","date":"2023-02-06 16:33:58.000000000","tz":-300},"subject":"Fix: use unaligned pointer accesses for lttng_inline_memcpy","message":"Fix: use unaligned pointer accesses for lttng_inline_memcpy\n\nlttng_inline_memcpy receives pointers which can be unaligned. This\ncauses issues (traps) specifically on arm 32-bit with 8-byte strings\n(including \\0).\n\nUse unaligned pointer accesses for loads/stores within\nlttng_inline_memcpy instead.\n\nThere is an impact on code generation on some architectures.  Using the\nfollowing test code on godbolt.org:\n\nvoid copy16_aligned(void *dest, void *src) {\n    *(uint16_t *)dest \u003d *(uint16_t *) src;\n}\n\nvoid copy16_unaligned(void *dest, void *src) {\n    STORE_UNALIGNED_INT(uint16_t, dest, LOAD_UNALIGNED_INT(uint16_t, src));\n}\n\nvoid copy32_aligned(void *dest, void *src) {\n    *(uint32_t *)dest \u003d *(uint32_t *) src;\n}\n\nvoid copy32_unaligned(void *dest, void *src) {\n    STORE_UNALIGNED_INT(uint32_t, dest, LOAD_UNALIGNED_INT(uint32_t, src));\n}\n\nvoid copy64_aligned(void *dest, void *src) {\n    *(uint64_t *)dest \u003d *(uint64_t *) src;\n}\n\nvoid copy64_unaligned(void *dest, void *src) {\n    STORE_UNALIGNED_INT(uint64_t, dest, LOAD_UNALIGNED_INT(uint64_t, src));\n}\n\nThe resulting assembler (gcc 12.2.0 in -O2) between aligned and\nunaligned:\n\n- x86-32: unchanged.\n- x86-64: unchanged.\n- powerpc32: unchanged.\n- powerpc64: unchanged.\n- arm32: 16 and 32-bit copy: unchanged. Added code for 64-bit unaligned copy.\n- aarch64: unchanged.\n- mips32: added code for unaligned.\n- mips64: added code for unaligned.\n- riscv: added code for unaligned.\n\nIf we want to improve the situation on mips and riscv, this would\nrequire introducing a new \"lttng_inline_integer_copy\" and expose\nadditional ring buffer client APIs in addition to event_write() which\ntake integers as inputs. Let\u0027s not introduce that complexity yet until\nit is justified.\n\nSigned-off-by: Mathieu Desnoyers \u003cmathieu.desnoyers@efficios.com\u003e\nChange-Id: I1e6471d4607ac6aff89f16ef24d5370e804b7612\n","web_links":[{"name":"gitweb","tooltip":"Open in GitWeb","url":"/gitweb?p\u003dlttng-ust.git;a\u003dcommit;h\u003d7670fe5d3f8877e324aea77cfd8bea8e72ced950"}],"resolve_conflicts_web_links":[{"name":"gitweb","tooltip":"Open in GitWeb","url":"/gitweb?p\u003dlttng-ust.git;a\u003dcommit;h\u003d7670fe5d3f8877e324aea77cfd8bea8e72ced950"}]},"branch":"refs/heads/master"},"7fdb690ce0a7187b23f439d569ddd629a702871f":{"kind":"NO_CHANGE","_number":3,"created":"2023-02-06 16:39:11.000000000","uploader":{"_account_id":1000009,"name":"Mathieu Desnoyers","email":"mathieu.desnoyers@efficios.com","username":"compudj","avatars":[{"url":"https://www.gravatar.com/avatar/7326b3e1d32b971a5e69d9730228c428.jpg?d\u003dretro\u0026r\u003dr\u0026s\u003d32","height":32},{"url":"https://www.gravatar.com/avatar/7326b3e1d32b971a5e69d9730228c428.jpg?d\u003dretro\u0026r\u003dr\u0026s\u003d56","height":56},{"url":"https://www.gravatar.com/avatar/7326b3e1d32b971a5e69d9730228c428.jpg?d\u003dretro\u0026r\u003dr\u0026s\u003d100","height":100},{"url":"https://www.gravatar.com/avatar/7326b3e1d32b971a5e69d9730228c428.jpg?d\u003dretro\u0026r\u003dr\u0026s\u003d120","height":120}]},"ref":"refs/changes/13/9413/3","fetch":{"anonymous http":{"url":"https://review.lttng.org/lttng-ust","ref":"refs/changes/13/9413/3","commands":{"Branch":"git fetch https://review.lttng.org/lttng-ust refs/changes/13/9413/3 \u0026\u0026 git checkout -b change-9413 FETCH_HEAD","Checkout":"git fetch https://review.lttng.org/lttng-ust refs/changes/13/9413/3 \u0026\u0026 git checkout FETCH_HEAD","Cherry Pick":"git fetch https://review.lttng.org/lttng-ust refs/changes/13/9413/3 \u0026\u0026 git cherry-pick FETCH_HEAD","Format Patch":"git fetch https://review.lttng.org/lttng-ust refs/changes/13/9413/3 \u0026\u0026 git format-patch -1 --stdout FETCH_HEAD","Pull":"git pull https://review.lttng.org/lttng-ust refs/changes/13/9413/3","Reset To":"git fetch https://review.lttng.org/lttng-ust refs/changes/13/9413/3 \u0026\u0026 git reset --hard FETCH_HEAD"}}},"commit":{"parents":[{"commit":"9c96e34c54f6e2beda872953c4d5955967c9fef4","subject":"ust-ctl: allow runtime version checks","web_links":[{"name":"gitweb","tooltip":"Open in GitWeb","url":"/gitweb?p\u003dlttng-ust.git;a\u003dcommit;h\u003d9c96e34c54f6e2beda872953c4d5955967c9fef4"}]}],"author":{"name":"Mathieu Desnoyers","email":"mathieu.desnoyers@efficios.com","date":"2023-02-02 15:25:57.000000000","tz":-300},"committer":{"name":"Mathieu Desnoyers","email":"mathieu.desnoyers@efficios.com","date":"2023-02-06 16:35:33.000000000","tz":-300},"subject":"Fix: use unaligned pointer accesses for lttng_inline_memcpy","message":"Fix: use unaligned pointer accesses for lttng_inline_memcpy\n\nlttng_inline_memcpy receives pointers which can be unaligned. This\ncauses issues (traps) specifically on arm 32-bit with 8-byte strings\n(including \\0).\n\nUse unaligned pointer accesses for loads/stores within\nlttng_inline_memcpy instead.\n\nThere is an impact on code generation on some architectures.  Using the\nfollowing test code on godbolt.org:\n\nvoid copy16_aligned(void *dest, void *src) {\n    *(uint16_t *)dest \u003d *(uint16_t *) src;\n}\n\nvoid copy16_unaligned(void *dest, void *src) {\n    STORE_UNALIGNED_INT(uint16_t, dest, LOAD_UNALIGNED_INT(uint16_t, src));\n}\n\nvoid copy32_aligned(void *dest, void *src) {\n    *(uint32_t *)dest \u003d *(uint32_t *) src;\n}\n\nvoid copy32_unaligned(void *dest, void *src) {\n    STORE_UNALIGNED_INT(uint32_t, dest, LOAD_UNALIGNED_INT(uint32_t, src));\n}\n\nvoid copy64_aligned(void *dest, void *src) {\n    *(uint64_t *)dest \u003d *(uint64_t *) src;\n}\n\nvoid copy64_unaligned(void *dest, void *src) {\n    STORE_UNALIGNED_INT(uint64_t, dest, LOAD_UNALIGNED_INT(uint64_t, src));\n}\n\nThe resulting assembler (gcc 12.2.0 in -O2) between aligned and\nunaligned:\n\n- x86-32: unchanged.\n- x86-64: unchanged.\n- powerpc32: unchanged.\n- powerpc64: unchanged.\n- arm32: 16 and 32-bit copy: unchanged. Added code for 64-bit unaligned copy.\n- aarch64: unchanged.\n- mips32: added code for unaligned.\n- mips64: added code for unaligned.\n- riscv: added code for unaligned.\n\nIf we want to improve the situation on mips and riscv, this would\nrequire introducing a new \"lttng_inline_integer_copy\" and expose\nadditional ring buffer client APIs in addition to event_write() which\ntake integers as inputs. Let\u0027s not introduce that complexity yet until\nit is justified.\n\nSigned-off-by: Mathieu Desnoyers \u003cmathieu.desnoyers@efficios.com\u003e\nChange-Id: I1e6471d4607ac6aff89f16ef24d5370e804b7612\n","web_links":[{"name":"gitweb","tooltip":"Open in GitWeb","url":"/gitweb?p\u003dlttng-ust.git;a\u003dcommit;h\u003d7fdb690ce0a7187b23f439d569ddd629a702871f"}],"resolve_conflicts_web_links":[{"name":"gitweb","tooltip":"Open in GitWeb","url":"/gitweb?p\u003dlttng-ust.git;a\u003dcommit;h\u003d7fdb690ce0a7187b23f439d569ddd629a702871f"}]},"branch":"refs/heads/master"}},"requirements":[],"submit_records":[],"submit_requirements":[]}