*/
int r14_off; /* Offset of saved %r14 */
int run_ctx_off; /* Offset of struct bpf_tramp_run_ctx */
+ int tccnt_off; /* Offset of saved tailcall counter */
int do_fexit; /* do_fexit: label */
};
tjit->r14_off = alloc_stack(tjit, sizeof(u64));
tjit->run_ctx_off = alloc_stack(tjit,
sizeof(struct bpf_tramp_run_ctx));
+ tjit->tccnt_off = alloc_stack(tjit, sizeof(u64));
/* The caller has already reserved STACK_FRAME_OVERHEAD bytes. */
tjit->stack_size -= STACK_FRAME_OVERHEAD;
tjit->orig_stack_args_off = tjit->stack_size + STACK_FRAME_OVERHEAD;
/* aghi %r15,-stack_size */
EMIT4_IMM(0xa70b0000, REG_15, -tjit->stack_size);
+ /* mvc tccnt_off(4,%r15),stack_size+STK_OFF_TCCNT(%r15) */
+ _EMIT6(0xd203f000 | tjit->tccnt_off,
+ 0xf000 | (tjit->stack_size + STK_OFF_TCCNT));
/* stmg %r2,%rN,fwd_reg_args_off(%r15) */
if (nr_reg_args)
EMIT6_DISP_LH(0xeb000000, 0x0024, REG_2,
(nr_stack_args * sizeof(u64) - 1) << 16 |
tjit->stack_args_off,
0xf000 | tjit->orig_stack_args_off);
+ /* mvc STK_OFF_TCCNT(4,%r15),tccnt_off(%r15) */
+ _EMIT6(0xd203f000 | STK_OFF_TCCNT, 0xf000 | tjit->tccnt_off);
/* lgr %r1,%r8 */
EMIT4(0xb9040000, REG_1, REG_8);
/* %r1() */
if (flags & (BPF_TRAMP_F_CALL_ORIG | BPF_TRAMP_F_RET_FENTRY_RET))
EMIT6_DISP_LH(0xe3000000, 0x0004, REG_2, REG_0, REG_15,
tjit->retval_off);
+ /* mvc stack_size+STK_OFF_TCCNT(4,%r15),tccnt_off(%r15) */
+ _EMIT6(0xd203f000 | (tjit->stack_size + STK_OFF_TCCNT),
+ 0xf000 | tjit->tccnt_off);
/* aghi %r15,stack_size */
EMIT4_IMM(0xa70b0000, REG_15, tjit->stack_size);
/* Emit an expoline for the following indirect jump. */