Whether or not we have RISCV_PROBE_VECTOR_UNALIGNED_ACCESS we need to
set up a cpu hotplug callback to check if we have vector at all,
since, when we don't have vector, we need to set
vector_misaligned_access to unsupported rather than leave it the
default of unknown.
Fixes: e7c9d66e313b ("RISC-V: Report vector unaligned access speed hwprobe")
Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
---
arch/riscv/kernel/unaligned_access_speed.c | 31 +++++++++++-----------
1 file changed, 16 insertions(+), 15 deletions(-)
diff --git a/arch/riscv/kernel/unaligned_access_speed.c b/arch/riscv/kernel/unaligned_access_speed.c
index c9d3237649bb..d9d4ca1fadc7 100644
--- a/arch/riscv/kernel/unaligned_access_speed.c
+++ b/arch/riscv/kernel/unaligned_access_speed.c
@@ -356,6 +356,20 @@ static void check_vector_unaligned_access(struct work_struct *work __always_unus
per_cpu(vector_misaligned_access, cpu) = speed;
}
+/* Measure unaligned access speed on all CPUs present at boot in parallel. */
+static int __init vec_check_unaligned_access_speed_all_cpus(void *unused __always_unused)
+{
+ schedule_on_each_cpu(check_vector_unaligned_access);
+
+ return 0;
+}
+#else /* CONFIG_RISCV_PROBE_VECTOR_UNALIGNED_ACCESS */
+static int __init vec_check_unaligned_access_speed_all_cpus(void *unused __always_unused)
+{
+ return 0;
+}
+#endif
+
static int riscv_online_cpu_vec(unsigned int cpu)
{
if (!has_vector()) {
@@ -363,27 +377,16 @@ static int riscv_online_cpu_vec(unsigned int cpu)
return 0;
}
+#ifdef CONFIG_RISCV_PROBE_VECTOR_UNALIGNED_ACCESS
if (per_cpu(vector_misaligned_access, cpu) != RISCV_HWPROBE_MISALIGNED_VECTOR_UNKNOWN)
return 0;
check_vector_unaligned_access_emulated(NULL);
check_vector_unaligned_access(NULL);
- return 0;
-}
-
-/* Measure unaligned access speed on all CPUs present at boot in parallel. */
-static int __init vec_check_unaligned_access_speed_all_cpus(void *unused __always_unused)
-{
- schedule_on_each_cpu(check_vector_unaligned_access);
+#endif
return 0;
}
-#else /* CONFIG_RISCV_PROBE_VECTOR_UNALIGNED_ACCESS */
-static int __init vec_check_unaligned_access_speed_all_cpus(void *unused __always_unused)
-{
- return 0;
-}
-#endif
static int __init check_unaligned_access_all_cpus(void)
{
@@ -409,10 +412,8 @@ static int __init check_unaligned_access_all_cpus(void)
cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, "riscv:online",
riscv_online_cpu, riscv_offline_cpu);
#endif
-#ifdef CONFIG_RISCV_PROBE_VECTOR_UNALIGNED_ACCESS
cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, "riscv:online",
riscv_online_cpu_vec, NULL);
-#endif
return 0;
}
--
2.48.1
On 07/02/2025 17:19, Andrew Jones wrote:
> Whether or not we have RISCV_PROBE_VECTOR_UNALIGNED_ACCESS we need to
> set up a cpu hotplug callback to check if we have vector at all,
> since, when we don't have vector, we need to set
> vector_misaligned_access to unsupported rather than leave it the
> default of unknown.
>
> Fixes: e7c9d66e313b ("RISC-V: Report vector unaligned access speed hwprobe")
> Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
> ---
> arch/riscv/kernel/unaligned_access_speed.c | 31 +++++++++++-----------
> 1 file changed, 16 insertions(+), 15 deletions(-)
>
> diff --git a/arch/riscv/kernel/unaligned_access_speed.c b/arch/riscv/kernel/unaligned_access_speed.c
> index c9d3237649bb..d9d4ca1fadc7 100644
> --- a/arch/riscv/kernel/unaligned_access_speed.c
> +++ b/arch/riscv/kernel/unaligned_access_speed.c
> @@ -356,6 +356,20 @@ static void check_vector_unaligned_access(struct work_struct *work __always_unus
> per_cpu(vector_misaligned_access, cpu) = speed;
> }
>
> +/* Measure unaligned access speed on all CPUs present at boot in parallel. */
> +static int __init vec_check_unaligned_access_speed_all_cpus(void *unused __always_unused)
> +{
> + schedule_on_each_cpu(check_vector_unaligned_access);
> +
> + return 0;
> +}
> +#else /* CONFIG_RISCV_PROBE_VECTOR_UNALIGNED_ACCESS */
> +static int __init vec_check_unaligned_access_speed_all_cpus(void *unused __always_unused)
> +{
> + return 0;
> +}
> +#endif
> +
> static int riscv_online_cpu_vec(unsigned int cpu)
> {
> if (!has_vector()) {
> @@ -363,27 +377,16 @@ static int riscv_online_cpu_vec(unsigned int cpu)
> return 0;
> }
>
> +#ifdef CONFIG_RISCV_PROBE_VECTOR_UNALIGNED_ACCESS
> if (per_cpu(vector_misaligned_access, cpu) != RISCV_HWPROBE_MISALIGNED_VECTOR_UNKNOWN)
> return 0;
>
> check_vector_unaligned_access_emulated(NULL);
> check_vector_unaligned_access(NULL);
> - return 0;
> -}
> -
> -/* Measure unaligned access speed on all CPUs present at boot in parallel. */
> -static int __init vec_check_unaligned_access_speed_all_cpus(void *unused __always_unused)
> -{
> - schedule_on_each_cpu(check_vector_unaligned_access);
> +#endif
>
> return 0;
> }
> -#else /* CONFIG_RISCV_PROBE_VECTOR_UNALIGNED_ACCESS */
> -static int __init vec_check_unaligned_access_speed_all_cpus(void *unused __always_unused)
> -{
> - return 0;
> -}
> -#endif
>
> static int __init check_unaligned_access_all_cpus(void)
> {
> @@ -409,10 +412,8 @@ static int __init check_unaligned_access_all_cpus(void)
> cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, "riscv:online",
> riscv_online_cpu, riscv_offline_cpu);
> #endif
> -#ifdef CONFIG_RISCV_PROBE_VECTOR_UNALIGNED_ACCESS
> cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, "riscv:online",
> riscv_online_cpu_vec, NULL);
> -#endif
>
> return 0;
> }
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Thanks,
Alex
On 07/02/2025 17:19, Andrew Jones wrote:
> Whether or not we have RISCV_PROBE_VECTOR_UNALIGNED_ACCESS we need to
> set up a cpu hotplug callback to check if we have vector at all,
> since, when we don't have vector, we need to set
> vector_misaligned_access to unsupported rather than leave it the
> default of unknown.
>
> Fixes: e7c9d66e313b ("RISC-V: Report vector unaligned access speed hwprobe")
> Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
> ---
> arch/riscv/kernel/unaligned_access_speed.c | 31 +++++++++++-----------
> 1 file changed, 16 insertions(+), 15 deletions(-)
>
> diff --git a/arch/riscv/kernel/unaligned_access_speed.c b/arch/riscv/kernel/unaligned_access_speed.c
> index c9d3237649bb..d9d4ca1fadc7 100644
> --- a/arch/riscv/kernel/unaligned_access_speed.c
> +++ b/arch/riscv/kernel/unaligned_access_speed.c
> @@ -356,6 +356,20 @@ static void check_vector_unaligned_access(struct work_struct *work __always_unus
> per_cpu(vector_misaligned_access, cpu) = speed;
> }
>
> +/* Measure unaligned access speed on all CPUs present at boot in parallel. */
> +static int __init vec_check_unaligned_access_speed_all_cpus(void *unused __always_unused)
> +{
> + schedule_on_each_cpu(check_vector_unaligned_access);
Hey Andrew,
While at it, could you add a comment stating that schedule_on_cpu()
(while documented as really slow) is used due to kernel_vector_begin()
needing interrupts to be enabled ? I stumbled upon that while reworking
misaligned.
Thanks,
Clément
> +
> + return 0;
> +}
> +#else /* CONFIG_RISCV_PROBE_VECTOR_UNALIGNED_ACCESS */
> +static int __init vec_check_unaligned_access_speed_all_cpus(void *unused __always_unused)
> +{
> + return 0;
> +}
> +#endif
> +
> static int riscv_online_cpu_vec(unsigned int cpu)
> {
> if (!has_vector()) {
> @@ -363,27 +377,16 @@ static int riscv_online_cpu_vec(unsigned int cpu)
> return 0;
> }
>
> +#ifdef CONFIG_RISCV_PROBE_VECTOR_UNALIGNED_ACCESS
> if (per_cpu(vector_misaligned_access, cpu) != RISCV_HWPROBE_MISALIGNED_VECTOR_UNKNOWN)
> return 0;
>
> check_vector_unaligned_access_emulated(NULL);
> check_vector_unaligned_access(NULL);
> - return 0;
> -}
> -
> -/* Measure unaligned access speed on all CPUs present at boot in parallel. */
> -static int __init vec_check_unaligned_access_speed_all_cpus(void *unused __always_unused)
> -{
> - schedule_on_each_cpu(check_vector_unaligned_access);
> +#endif
>
> return 0;
> }
> -#else /* CONFIG_RISCV_PROBE_VECTOR_UNALIGNED_ACCESS */
> -static int __init vec_check_unaligned_access_speed_all_cpus(void *unused __always_unused)
> -{
> - return 0;
> -}
> -#endif
>
> static int __init check_unaligned_access_all_cpus(void)
> {
> @@ -409,10 +412,8 @@ static int __init check_unaligned_access_all_cpus(void)
> cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, "riscv:online",
> riscv_online_cpu, riscv_offline_cpu);
> #endif
> -#ifdef CONFIG_RISCV_PROBE_VECTOR_UNALIGNED_ACCESS
> cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, "riscv:online",
> riscv_online_cpu_vec, NULL);
> -#endif
>
> return 0;
> }
On Fri, Feb 07, 2025 at 06:36:28PM +0100, Clément Léger wrote:
>
>
> On 07/02/2025 17:19, Andrew Jones wrote:
> > Whether or not we have RISCV_PROBE_VECTOR_UNALIGNED_ACCESS we need to
> > set up a cpu hotplug callback to check if we have vector at all,
> > since, when we don't have vector, we need to set
> > vector_misaligned_access to unsupported rather than leave it the
> > default of unknown.
> >
> > Fixes: e7c9d66e313b ("RISC-V: Report vector unaligned access speed hwprobe")
> > Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
> > ---
> > arch/riscv/kernel/unaligned_access_speed.c | 31 +++++++++++-----------
> > 1 file changed, 16 insertions(+), 15 deletions(-)
> >
> > diff --git a/arch/riscv/kernel/unaligned_access_speed.c b/arch/riscv/kernel/unaligned_access_speed.c
> > index c9d3237649bb..d9d4ca1fadc7 100644
> > --- a/arch/riscv/kernel/unaligned_access_speed.c
> > +++ b/arch/riscv/kernel/unaligned_access_speed.c
> > @@ -356,6 +356,20 @@ static void check_vector_unaligned_access(struct work_struct *work __always_unus
> > per_cpu(vector_misaligned_access, cpu) = speed;
> > }
> >
> > +/* Measure unaligned access speed on all CPUs present at boot in parallel. */
> > +static int __init vec_check_unaligned_access_speed_all_cpus(void *unused __always_unused)
> > +{
> > + schedule_on_each_cpu(check_vector_unaligned_access);
> Hey Andrew,
>
> While at it, could you add a comment stating that schedule_on_cpu()
> (while documented as really slow) is used due to kernel_vector_begin()
> needing interrupts to be enabled ? I stumbled upon that while reworking
> misaligned.
That should be a separate patch, since this patch is mostly just moving
code (not even this function was "moved", but git-diff prefers to say it
was moved rather than what was actually moved...)
I guess the comment patch you suggest should go in your rework series.
Thanks,
drew
>
> Thanks,
>
> Clément
>
> > +
> > + return 0;
> > +}
> > +#else /* CONFIG_RISCV_PROBE_VECTOR_UNALIGNED_ACCESS */
> > +static int __init vec_check_unaligned_access_speed_all_cpus(void *unused __always_unused)
> > +{
> > + return 0;
> > +}
> > +#endif
> > +
> > static int riscv_online_cpu_vec(unsigned int cpu)
> > {
> > if (!has_vector()) {
> > @@ -363,27 +377,16 @@ static int riscv_online_cpu_vec(unsigned int cpu)
> > return 0;
> > }
> >
> > +#ifdef CONFIG_RISCV_PROBE_VECTOR_UNALIGNED_ACCESS
> > if (per_cpu(vector_misaligned_access, cpu) != RISCV_HWPROBE_MISALIGNED_VECTOR_UNKNOWN)
> > return 0;
> >
> > check_vector_unaligned_access_emulated(NULL);
> > check_vector_unaligned_access(NULL);
> > - return 0;
> > -}
> > -
> > -/* Measure unaligned access speed on all CPUs present at boot in parallel. */
> > -static int __init vec_check_unaligned_access_speed_all_cpus(void *unused __always_unused)
> > -{
> > - schedule_on_each_cpu(check_vector_unaligned_access);
> > +#endif
> >
> > return 0;
> > }
> > -#else /* CONFIG_RISCV_PROBE_VECTOR_UNALIGNED_ACCESS */
> > -static int __init vec_check_unaligned_access_speed_all_cpus(void *unused __always_unused)
> > -{
> > - return 0;
> > -}
> > -#endif
> >
> > static int __init check_unaligned_access_all_cpus(void)
> > {
> > @@ -409,10 +412,8 @@ static int __init check_unaligned_access_all_cpus(void)
> > cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, "riscv:online",
> > riscv_online_cpu, riscv_offline_cpu);
> > #endif
> > -#ifdef CONFIG_RISCV_PROBE_VECTOR_UNALIGNED_ACCESS
> > cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, "riscv:online",
> > riscv_online_cpu_vec, NULL);
> > -#endif
> >
> > return 0;
> > }
>
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