Pierrick Bouvier <pierrick.bouv...@linaro.org> writes:
> Extend plugins API to support callback called with a given criteria
> (evaluated inline).
>
> Added functions:
> - qemu_plugin_register_vcpu_tb_exec_cond_cb
> - qemu_plugin_register_vcpu_insn_exec_cond_cb
>
> They expect as parameter a condition, a qemu_plugin_u64_t (op1) and an
> immediate (op2). Callback is called if op1 |cond| op2 is true.
>
> Signed-off-by: Pierrick Bouvier <pierrick.bouv...@linaro.org>
<snip>
>
> +static TCGCond plugin_cond_to_tcgcond(enum qemu_plugin_cond cond)
> +{
> + switch (cond) {
> + case QEMU_PLUGIN_COND_EQ:
> + return TCG_COND_EQ;
> + case QEMU_PLUGIN_COND_NE:
> + return TCG_COND_NE;
> + case QEMU_PLUGIN_COND_LT:
> + return TCG_COND_LTU;
> + case QEMU_PLUGIN_COND_LE:
> + return TCG_COND_LEU;
> + case QEMU_PLUGIN_COND_GT:
> + return TCG_COND_GTU;
> + case QEMU_PLUGIN_COND_GE:
> + return TCG_COND_GEU;
> + default:
> + /* ALWAYS and NEVER conditions should never reach */
> + g_assert_not_reached();
> + }
> +}
> +
> +static TCGOp *append_cond_udata_cb(const struct qemu_plugin_dyn_cb *cb,
> + TCGOp *begin_op, TCGOp *op, int *cb_idx)
> +{
> + char *ptr = cb->cond_cb.entry.score->data->data;
> + size_t elem_size = g_array_get_element_size(
> + cb->cond_cb.entry.score->data);
> + size_t offset = cb->cond_cb.entry.offset;
> + /* Condition should be negated, as calling the cb is the "else" path */
> + TCGCond cond = tcg_invert_cond(plugin_cond_to_tcgcond(cb->cond_cb.cond));
> +
> + op = copy_const_ptr(&begin_op, op, ptr);
> + op = copy_ld_i32(&begin_op, op);
> + op = copy_mul_i32(&begin_op, op, elem_size);
> + op = copy_ext_i32_ptr(&begin_op, op);
> + op = copy_const_ptr(&begin_op, op, ptr + offset);
> + op = copy_add_ptr(&begin_op, op);
> + op = copy_ld_i64(&begin_op, op);
> + op = copy_brcondi_i64(&begin_op, op, cond, cb->cond_cb.imm);
> + op = copy_call(&begin_op, op, cb->f.vcpu_udata, cb_idx);
> + op = copy_set_label(&begin_op, op);
> + return op;
I think we are missing something here to ensure that udata is set
correctly for the callback, see my RFC:
Subject: [RFC PATCH] contrib/plugins: control flow plugin (WIP!)
Date: Mon, 11 Mar 2024 15:34:32 +0000
Message-Id: <20240311153432.1395190-1-alex.ben...@linaro.org>
which is seeing the same value every time in the callback.
--
Alex Bennée
Virtualisation Tech Lead @ Linaro
