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https://github.com/AuxXxilium/linux_dsm_epyc7002.git
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a14a07b801
IA64 dynamic ftrace support. The original _mcount stub for each function is like: alloc r40=ar.pfs,12,8,0 mov r43=r0;; mov r42=b0 mov r41=r1 nop.i 0x0 br.call.sptk.many b0 = _mcount;; The patch convert it to below for nop: [MII] nop.m 0x0 mov r3=ip nop.i 0x0 [MLX] nop.m 0x0 nop.x 0x0;; This isn't completely nop, as there is one instuction 'mov r3=ip', but it should be light and harmless for code follow it. And below is for call [MII] nop.m 0x0 mov r3=ip nop.i 0x0 [MLX] nop.m 0x0 brl.many .;; In this way, only one instruction is changed to convert code between nop and call. This should meet dyn-ftrace's requirement. But this requires CPU support brl instruction, so dyn-ftrace isn't supported for old Itanium system. Assume there are quite few such old system running. Signed-off-by: Shaohua Li <shaohua.li@intel.com> Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> |
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| .. | ||
| configs | ||
| dig | ||
| hp | ||
| ia32 | ||
| include/asm | ||
| kernel | ||
| kvm | ||
| lib | ||
| mm | ||
| oprofile | ||
| pci | ||
| scripts | ||
| sn | ||
| uv | ||
| xen | ||
| install.sh | ||
| Kconfig | ||
| Kconfig.debug | ||
| Makefile | ||
| module.lds | ||