Currently when an event probe (eprobe) hooks to a string field, it does not display it as a string, but instead as a number. This makes the field rather useless. Handle the different kinds of strings, dynamic, static, relational/dynamic etc. Now when a string field is used, the ":string" type can be used to display it: echo "e:sw sched/sched_switch comm=$next_comm:string" > dynamic_events Link: https://lkml.kernel.org/r/20220820134400.959640191@goodmis.org
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| @@ -311,6 +311,27 @@ static unsigned long get_event_field(struct fetch_insn *code, void *rec) · 310 unmodified lines | ||
| 311 | 311 | |
| 312 | 312 | addr = rec + field->offset; |
| 313 | 313 | |
| 314 | + if (is_string_field(field)) { | |
| 315 | + switch (field->filter_type) { | |
| 316 | + case FILTER_DYN_STRING: | |
| 317 | + val = (unsigned long)(rec + (*(unsigned int *)addr & 0xffff)); | |
| 318 | + break; | |
| 319 | + case FILTER_RDYN_STRING: | |
| 320 | + val = (unsigned long)(addr + (*(unsigned int *)addr & 0xffff)); | |
| 321 | + break; | |
| 322 | + case FILTER_STATIC_STRING: | |
| 323 | + val = (unsigned long)addr; | |
| 324 | + break; | |
| 325 | + case FILTER_PTR_STRING: | |
| 326 | + val = (unsigned long)(*(char *)addr); | |
| 327 | + break; | |
| 328 | + default: | |
| 329 | + WARN_ON_ONCE(1); | |
| 330 | + return 0; | |
| 331 | + } | |
| 332 | + return val; | |
| 333 | + } | |
| 334 | + | |
| 314 | 335 | switch (field->size) { |
| 315 | 336 | case 1: |
| 316 | 337 | if (field->is_signed) |