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X-MS-Exchange-AntiSpam-MessageData: =?us-ascii?Q?l3HaDAjVc3gg445UhRkTYkvCMfGwMAPIZSpTpNYj0fEH/nZ0Ndcy4dB11Ech?= =?us-ascii?Q?5TB47qXLCIN6ucRy74x36C2fADcjuKCmm5AoIT/CJsQbUUf7odTNvY6aR90v?= =?us-ascii?Q?WkcBJNuOuSLfoqtxFRIsB5gjQpbMckB/2MbJK3j91oCAzGmHvhcS8ErnnZi8?= =?us-ascii?Q?3FyuVftRx4FcHm6vyOPlagXmSto84iWFXTC4Xm9/OvZbdzsA/Tjc/DK/DTAx?= =?us-ascii?Q?pxHs46O06LiTCsIi4+wAnEoWIM1Vmc8XgxRXg85NI01I7R32XTlJBCDPW9oK?= =?us-ascii?Q?fDU3bDrkj5tRJtCb/e1oxTsMpNihPi/MbxZe+/bBY0FbkvZ2r3A8CAM8gwf+?= =?us-ascii?Q?Agnv/tk6NCyFJPOynzgISAZuOsuD+4BtaUTRB2BovyLHpGCDEODCxuEp2FeV?= =?us-ascii?Q?FXIp2ykhye9z51Hqege1z8UzIcfRRxw6qiahwgFv7cCIFVIsZsNcQHib/dTG?= =?us-ascii?Q?HDP4fsNNJl4XsGAIVGh4HUEeIUHwRmK5WjvPJW4/xErhtfPzPyytuify2XB5?= =?us-ascii?Q?GE8KGMkWwmZoWF6x9M6JiK3NNQbAQ4UJVnAeKodw1K/uiiNu+9Ro6LI2OBa5?= =?us-ascii?Q?eAJZgo4+Ug4MYJ5cjvkIZTcFp9ZOL51eLlbnDcS4mIRbjGBLGCZUBPJiyn7W?= =?us-ascii?Q?OnQvhMBQzltUFHR80gQGWfIedQ1XLJ+/TUlYr1PixBSr7RsDW3F/7BXGTtVu?= =?us-ascii?Q?Jb35xjuCxWwaLUImX42Z/PdHc1F7VlqfyBUeTIUoCM6x81VJ10fPXzjgd0vc?= =?us-ascii?Q?A6noz2k8dKKFgbO0KKAikfS+VzZLbAtmwFa4fhwN3LTZq8tFIVW6ThNoKaA9?= =?us-ascii?Q?tDIqpJHtmZEEEW738V5p9lt3FpTnZPXm1iCtOBbcXAcLMWtz4hQig8JfZ+2b?= =?us-ascii?Q?MkX74qsx6Uyw7Zdgs8opwaw5jOe0su5Gs4PLUQptoEwP0vpSoWYeYKkjrucL?= =?us-ascii?Q?4O3cV+6p51FqnLwbYkcpi8/tJPPbWstJcpgXqB9Z+RdiJOm3ehedsxOOQF4z?= =?us-ascii?Q?PlEIpOEzrrE3Mn9/Xx2G5fg5O2qW3109nI6lS1ALlRdpyOVPGfGz5D30TDxT?= =?us-ascii?Q?/Ew0d7h5fmcUnzfmTJhs8jo9kwzgXlubMOyaox7pZSE+LtSmBZeFq3O6o2HA?= =?us-ascii?Q?BqnU5b9cu4AjXyTpo9b6VSzdedMip46ovXzC8K40ysZQWRzIf7mTOVoLnnof?= =?us-ascii?Q?bgIHpf5866qbEGuNi29MjUWacbV9K12YtzpxkONulTipOBc7YeyDQRBiZXsZ?= =?us-ascii?Q?PRyt/QSY8HzPcoslzlABjhbjE5cIv5/iMc91jXMEwjhby094QRI7exyZCoyb?= =?us-ascii?Q?mJuEtKOdyQSqUfp2VYji590EovvWN/edfAWroL4LWIlJag=3D=3D?= X-MS-Exchange-CrossTenant-Network-Message-Id: b1b4fa50-95af-4e20-c443-08d909a93386 X-MS-Exchange-CrossTenant-AuthSource: BY5PR15MB3571.namprd15.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 27 Apr 2021 18:20:57.3086 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 8ae927fe-1255-47a7-a2af-5f3a069daaa2 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: JXCti6/okOybELWO7NNyEWWygOlHHkP35OIYn7EiZ2BZolqO4MZjhh8QPar3WeS/ X-MS-Exchange-Transport-CrossTenantHeadersStamped: BY3PR15MB4882 X-OriginatorOrg: fb.com X-Proofpoint-ORIG-GUID: 5eCbYOCbj3cs7cpQbmrR76427G-dC5fu X-Proofpoint-GUID: 5eCbYOCbj3cs7cpQbmrR76427G-dC5fu X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.391,18.0.761 definitions=2021-04-27_10:2021-04-27,2021-04-27 signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 adultscore=0 mlxscore=0 phishscore=0 malwarescore=0 bulkscore=0 mlxlogscore=999 lowpriorityscore=0 clxscore=1015 spamscore=0 suspectscore=0 impostorscore=0 priorityscore=1501 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2104060000 definitions=main-2104270123 X-FB-Internal: deliver Precedence: bulk List-ID: X-Mailing-List: dwarves@vger.kernel.org On Tue, Apr 27, 2021 at 01:42:40PM +0200, Jiri Olsa wrote: > On Fri, Apr 23, 2021 at 02:37:28PM -0700, Martin KaFai Lau wrote: > > SNIP > > > +static int collect_listed_functions(struct btf_elf *btfe, GElf_Sym *sym, > > + size_t sym_sec_idx) > > +{ > > + int len, digits = 0, underscores = 0; > > + const char *name; > > + char *func_name; > > + > > + if (!btfe->btf_ids_shndx || > > + btfe->btf_ids_shndx != sym_sec_idx) > > + return 0; > > + > > + /* The kernel function in the btf id list will have symbol like: > > + * __BTF_ID__func____[digit]+ > > + */ > > + name = elf_sym__name(sym, btfe->symtab); > > + if (strncmp(name, BTF_ID_FUNC_PREFIX, BTF_ID_FUNC_PREFIX_LEN)) > > + return 0; > > + > > + name += BTF_ID_FUNC_PREFIX_LEN; > > + > > + /* name: __[digit]+ > > + * Strip the ending __[digit]+ > > + */ > > + for (len = strlen(name); len && underscores != 2; len--) { > > + char c = name[len - 1]; > > + > > + if (c == '_') { > > + if (!digits) > > + return 0; > > + underscores++; > > + } else if (isdigit(c)) { > > + if (underscores) > > + return 0; > > + digits++; > > + } else { > > + return 0; > > + } > > + } > > + > > + if (!len) > > + return 0; > > + > > + func_name = strndup(name, len); > > + if (!func_name) { > > + fprintf(stderr, > > + "Failed to alloc memory for listed function %s%s\n", > > + BTF_ID_FUNC_PREFIX, name); > > + return -1; > > + } > > + > > + if (is_listed_func(func_name)) { > > + /* already captured */ > > + free(func_name); > > + return 0; > > + } > > + > > + /* grow listed_functions */ > > + if (listed_functions_cnt == listed_functions_alloc) { > > + char **new; > > + > > + listed_functions_alloc = max(100, > > + listed_functions_alloc * 3 / 2); > > + new = realloc(listed_functions, > > + listed_functions_alloc * sizeof(*listed_functions)); > > + if (!new) { > > + fprintf(stderr, > > + "Failed to alloc memory for listed function %s%s\n", > > + BTF_ID_FUNC_PREFIX, name); > > + free(func_name); > > + return -1; > > + } > > + listed_functions = new; > > + } > > + > > + listed_functions[listed_functions_cnt++] = func_name; > > + qsort(listed_functions, listed_functions_cnt, > > + sizeof(*listed_functions), listed_function_cmp); > > I was thinking of doing this at the end in setup_functions, > but we need to do name lookups before adding.. I am planning to just use btf__add_str() as Andrii suggested. Then most of these will go away.