| Message ID | 20250321125737.72839-4-philmd@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | tcg: Move TCG_GUEST_DEFAULT_MO -> TCGCPUOps::guest_default_memory_order | expand |
On 21/03/25, Philippe Mathieu-Daudé wrote: > In order to use TCG with multiple targets, replace the > compile time use of TCG_GUEST_DEFAULT_MO by a runtime > access to tcg_ctx->guest_mo. > > Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org> > --- > accel/tcg/internal-target.h | 4 +--- > 1 file changed, 1 insertion(+), 3 deletions(-) > > diff --git a/accel/tcg/internal-target.h b/accel/tcg/internal-target.h > index 1cb35dba99e..014ee756f9d 100644 > --- a/accel/tcg/internal-target.h > +++ b/accel/tcg/internal-target.h > @@ -49,11 +49,9 @@ G_NORETURN void cpu_io_recompile(CPUState *cpu, uintptr_t retaddr); > * Filter @type to the barrier that is required for the guest > * memory ordering vs the host memory ordering. A non-zero > * result indicates that some barrier is required. > - * > - * This is a macro so that it's constant even without optimization. > */ > #define tcg_req_mo(type) \ > - ((type) & TCG_GUEST_DEFAULT_MO & ~TCG_TARGET_DEFAULT_MO) > + ((type) & tcg_ctx->guest_mo & ~TCG_TARGET_DEFAULT_MO) > > /** > * cpu_req_mo: > -- > 2.47.1 > I'll parrot some older feedback by Richard https://lore.kernel.org/all/92cc9335-10bf-4a74-9eb4-249de5545dc5@linaro.org/ but tcg_ctx->guest_mo can be undefined or bogus here. Could we not take cpu and access cpu->cc->tcg_ops->guest_default_memory_order directly instead?
On 21/3/25 15:39, Anton Johansson wrote: > On 21/03/25, Philippe Mathieu-Daudé wrote: >> In order to use TCG with multiple targets, replace the >> compile time use of TCG_GUEST_DEFAULT_MO by a runtime >> access to tcg_ctx->guest_mo. >> >> Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org> >> --- >> accel/tcg/internal-target.h | 4 +--- >> 1 file changed, 1 insertion(+), 3 deletions(-) >> >> diff --git a/accel/tcg/internal-target.h b/accel/tcg/internal-target.h >> index 1cb35dba99e..014ee756f9d 100644 >> --- a/accel/tcg/internal-target.h >> +++ b/accel/tcg/internal-target.h >> @@ -49,11 +49,9 @@ G_NORETURN void cpu_io_recompile(CPUState *cpu, uintptr_t retaddr); >> * Filter @type to the barrier that is required for the guest >> * memory ordering vs the host memory ordering. A non-zero >> * result indicates that some barrier is required. >> - * >> - * This is a macro so that it's constant even without optimization. >> */ >> #define tcg_req_mo(type) \ >> - ((type) & TCG_GUEST_DEFAULT_MO & ~TCG_TARGET_DEFAULT_MO) >> + ((type) & tcg_ctx->guest_mo & ~TCG_TARGET_DEFAULT_MO) >> >> /** >> * cpu_req_mo: >> -- >> 2.47.1 >> > > I'll parrot some older feedback by Richard > > https://lore.kernel.org/all/92cc9335-10bf-4a74-9eb4-249de5545dc5@linaro.org/ > > but tcg_ctx->guest_mo can be undefined or bogus here. Could we not > take cpu and access cpu->cc->tcg_ops->guest_default_memory_order > directly instead? Yes, cpu_req_mo() has access to @cpu.
On 3/21/25 05:57, Philippe Mathieu-Daudé wrote: > In order to use TCG with multiple targets, replace the > compile time use of TCG_GUEST_DEFAULT_MO by a runtime > access to tcg_ctx->guest_mo. > > Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org> > --- > accel/tcg/internal-target.h | 4 +--- > 1 file changed, 1 insertion(+), 3 deletions(-) > > diff --git a/accel/tcg/internal-target.h b/accel/tcg/internal-target.h > index 1cb35dba99e..014ee756f9d 100644 > --- a/accel/tcg/internal-target.h > +++ b/accel/tcg/internal-target.h > @@ -49,11 +49,9 @@ G_NORETURN void cpu_io_recompile(CPUState *cpu, uintptr_t retaddr); > * Filter @type to the barrier that is required for the guest > * memory ordering vs the host memory ordering. A non-zero > * result indicates that some barrier is required. > - * > - * This is a macro so that it's constant even without optimization. > */ > #define tcg_req_mo(type) \ > - ((type) & TCG_GUEST_DEFAULT_MO & ~TCG_TARGET_DEFAULT_MO) > + ((type) & tcg_ctx->guest_mo & ~TCG_TARGET_DEFAULT_MO) Incorrect. The setting in tcg_ctx is only valid during compilation. This macro is used during execution, in cpu_req_mo(), from the cpu memory access routines. r~
diff --git a/accel/tcg/internal-target.h b/accel/tcg/internal-target.h index 1cb35dba99e..014ee756f9d 100644 --- a/accel/tcg/internal-target.h +++ b/accel/tcg/internal-target.h @@ -49,11 +49,9 @@ G_NORETURN void cpu_io_recompile(CPUState *cpu, uintptr_t retaddr); * Filter @type to the barrier that is required for the guest * memory ordering vs the host memory ordering. A non-zero * result indicates that some barrier is required. - * - * This is a macro so that it's constant even without optimization. */ #define tcg_req_mo(type) \ - ((type) & TCG_GUEST_DEFAULT_MO & ~TCG_TARGET_DEFAULT_MO) + ((type) & tcg_ctx->guest_mo & ~TCG_TARGET_DEFAULT_MO) /** * cpu_req_mo:
In order to use TCG with multiple targets, replace the compile time use of TCG_GUEST_DEFAULT_MO by a runtime access to tcg_ctx->guest_mo. Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org> --- accel/tcg/internal-target.h | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-)