Richard Henderson <richard.hender...@linaro.org> writes:
> This is a perfectly natural occurrence for x86 "rep movb",
> where the "rep" prefix forms a counted loop of the one insn.
>
> During the tests/tcg/multiarch/memory test, this logging is
> triggered over 350000 times. Within the context of cross-i386-tci
> build, which is already slow by nature, the logging is sufficient
> to push the test into timeout.
How does this get triggered because I added these:
# non-inline runs will trigger the duplicate instruction heuristics in
libinsn.so
run-plugin-%-with-libinsn.so:
$(call run-test, $@, \
$(QEMU) -monitor none -display none \
-chardev file$(COMMA)path=$@.out$(COMMA)id=output \
-plugin ../../plugin/libinsn.so$(COMMA)inline=on \
-d plugin -D $*-with-libinsn.so.pout \
$(QEMU_OPTS) $*)
to prevent the callback versions from being called for x86. The original
intent of the check was to detect failures due to cpu_io_recompile, see
e025d799af (tests/plugin: expand insn test to detect duplicate instructions)
>
> Signed-off-by: Richard Henderson <richard.hender...@linaro.org>
> ---
> Irritatingly, it doesn't timeout locally, so I used staging to double-check:
>
> Fail: https://gitlab.com/qemu-project/qemu/-/jobs/4450754282#L5062
> Pass: https://gitlab.com/qemu-project/qemu/-/jobs/4450927108
> ---
> tests/plugin/insn.c | 9 +--------
> 1 file changed, 1 insertion(+), 8 deletions(-)
>
> diff --git a/tests/plugin/insn.c b/tests/plugin/insn.c
> index cd5ea5d4ae..9bd6e44f73 100644
> --- a/tests/plugin/insn.c
> +++ b/tests/plugin/insn.c
> @@ -19,7 +19,6 @@ QEMU_PLUGIN_EXPORT int qemu_plugin_version =
> QEMU_PLUGIN_VERSION;
> #define MAX_CPUS 8 /* lets not go nuts */
>
> typedef struct {
> - uint64_t last_pc;
> uint64_t insn_count;
> } InstructionCount;
>
> @@ -51,13 +50,7 @@ static void vcpu_insn_exec_before(unsigned int cpu_index,
> void *udata)
> {
> unsigned int i = cpu_index % MAX_CPUS;
> InstructionCount *c = &counts[i];
> - uint64_t this_pc = GPOINTER_TO_UINT(udata);
> - if (this_pc == c->last_pc) {
> - g_autofree gchar *out = g_strdup_printf("detected repeat execution @
> 0x%"
> - PRIx64 "\n", this_pc);
> - qemu_plugin_outs(out);
> - }
> - c->last_pc = this_pc;
> +
> c->insn_count++;
> }
--
Alex Bennée
Virtualisation Tech Lead @ Linaro
