| Message ID | 20231208113529.74067-5-philmd@linaro.org |
|---|---|
| State | Superseded |
| Headers | show |
| Series | sysemu/replay: Restrict icount to TCG system emulation | expand |
On 12/8/23 03:35, Philippe Mathieu-Daudé wrote: > pmu_init() register its event checking the pm_event::supported() > handler. For INST_RETIRED, the event is only registered and the > bit enabled in the PMU Common Event Identification register when > icount is enabled as ICOUNT_PRECISE. > > PMU events are TCG-only, hardware accelerators handle them > directly. Unfortunately we register the events in non-TCG builds, > leading to linking error such: > > ld: Undefined symbols: > _icount_to_ns, referenced from: > _instructions_ns_per in target_arm_helper.c.o > clang: error: linker command failed with exit code 1 (use -v to see invocation) > > As a kludge, give a hint to the compiler by asserting the > pm_event::get_count() and pm_event::ns_per_count() handler will > only be called under this icount mode. > > Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org> > --- > As discussed in > https://lore.kernel.org/qemu-devel/CAFEAcA-HVf8vWLzmdStEo2NrSKQdZV612rBjiaj-gLW4vXyvpA@mail.gmail.com/ > better would be to restrict the PMU events to TCG, but this is > out of the scope of this series. Reviewed-by: Richard Henderson <richard.henderson@linaro.org> r~
diff --git a/target/arm/helper.c b/target/arm/helper.c index adb0960bba..333fd5f4bf 100644 --- a/target/arm/helper.c +++ b/target/arm/helper.c @@ -940,11 +940,13 @@ static bool instructions_supported(CPUARMState *env) static uint64_t instructions_get_count(CPUARMState *env) { + assert(icount_enabled() == ICOUNT_PRECISE); return (uint64_t)icount_get_raw(); } static int64_t instructions_ns_per(uint64_t icount) { + assert(icount_enabled() == ICOUNT_PRECISE); return icount_to_ns((int64_t)icount); } #endif
pmu_init() register its event checking the pm_event::supported() handler. For INST_RETIRED, the event is only registered and the bit enabled in the PMU Common Event Identification register when icount is enabled as ICOUNT_PRECISE. PMU events are TCG-only, hardware accelerators handle them directly. Unfortunately we register the events in non-TCG builds, leading to linking error such: ld: Undefined symbols: _icount_to_ns, referenced from: _instructions_ns_per in target_arm_helper.c.o clang: error: linker command failed with exit code 1 (use -v to see invocation) As a kludge, give a hint to the compiler by asserting the pm_event::get_count() and pm_event::ns_per_count() handler will only be called under this icount mode. Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org> --- As discussed in https://lore.kernel.org/qemu-devel/CAFEAcA-HVf8vWLzmdStEo2NrSKQdZV612rBjiaj-gLW4vXyvpA@mail.gmail.com/ better would be to restrict the PMU events to TCG, but this is out of the scope of this series. --- target/arm/helper.c | 2 ++ 1 file changed, 2 insertions(+)