On Thu, 3 Sep 2020 22:04:38 -0300
Daniel Henrique Barboza <danielhb...@gmail.com> wrote:
> The work to be done in h_home_node_associativity() intersects
> with what is already done in spapr_numa_fixup_cpu_dt(). This
> patch creates a new helper, spapr_numa_get_vcpu_assoc(), to
> be used for both spapr_numa_fixup_cpu_dt() and
> h_home_node_associativity().
>
> While we're at it, use memcpy() instead of loop assignment
> to created the returned array.
>
> Signed-off-by: Daniel Henrique Barboza <danielhb...@gmail.com>
> ---
Hi Daniel,
A few comments below.
> hw/ppc/spapr_numa.c | 30 ++++++++++++++++++++----------
> 1 file changed, 20 insertions(+), 10 deletions(-)
>
> diff --git a/hw/ppc/spapr_numa.c b/hw/ppc/spapr_numa.c
> index 368c1a494d..980a6488bf 100644
> --- a/hw/ppc/spapr_numa.c
> +++ b/hw/ppc/spapr_numa.c
> @@ -71,13 +71,15 @@ void spapr_numa_write_associativity_dt(SpaprMachineState
> *spapr, void *fdt,
> sizeof(spapr->numa_assoc_array[nodeid]))));
> }
>
> -int spapr_numa_fixup_cpu_dt(SpaprMachineState *spapr, void *fdt,
> - int offset, PowerPCCPU *cpu)
> +static uint32_t *spapr_numa_get_vcpu_assoc(SpaprMachineState *spapr,
> + PowerPCCPU *cpu,
> + uint *vcpu_assoc_size)
> {
> - uint vcpu_assoc_size = NUMA_ASSOC_SIZE + 1;
> - uint32_t vcpu_assoc[vcpu_assoc_size];
> + uint32_t *vcpu_assoc = NULL;
You don't need to initialize this pointer since it is assigned a value
unconditionally just below.
> int index = spapr_get_vcpu_id(cpu);
> - int i;
> +
> + *vcpu_assoc_size = (NUMA_ASSOC_SIZE + 1) * sizeof(uint32_t);
It's a bit weird to return something that is definitely a compile
time constant by reference... What about introducing a macro ?
#define VCPU_NUMA_ASSOC_SIZE (NUMA_ASSOC_SIZE + 1)
> + vcpu_assoc = g_malloc(*vcpu_assoc_size);
>
vcpu_assoc = g_new(uint32_t, VCPU_NUMA_ASSOC_SIZE);
> /*
> * VCPUs have an extra 'cpu_id' value in ibm,associativity
> @@ -86,16 +88,24 @@ int spapr_numa_fixup_cpu_dt(SpaprMachineState *spapr,
> void *fdt,
> * cpu_id last.
> */
> vcpu_assoc[0] = cpu_to_be32(MAX_DISTANCE_REF_POINTS + 1);
> + memcpy(vcpu_assoc + 1, spapr->numa_assoc_array[cpu->node_id],
> + MAX_DISTANCE_REF_POINTS);
> + vcpu_assoc[MAX_DISTANCE_REF_POINTS + 1] = cpu_to_be32(index);
>
memcpy(vcpu_assoc + 1, spapr->numa_assoc_array[cpu->node_id],
(VPCU_ASSOC_SIZE - 2) * sizeof(uint32_t));
vcpu_assoc[VCPU_ASSOC_SIZE - 1] = cpu_to_be32(index);
I personally find more clear than using MAX_DISTANCE_REF_POINTS in an array
that was just allocated with NUMA_ASSOC_SIZE... one has to check spapr.h
to see that NUMA_ASSOC_SIZE == MAX_DISTANCE_REF_POINTS + 1
> - for (i = 1; i <= MAX_DISTANCE_REF_POINTS; i++) {
> - vcpu_assoc[i] = spapr->numa_assoc_array[cpu->node_id][i];
> - }
> + return vcpu_assoc;
> +}
> +
> +int spapr_numa_fixup_cpu_dt(SpaprMachineState *spapr, void *fdt,
> + int offset, PowerPCCPU *cpu)
> +{
> + g_autofree uint32_t *vcpu_assoc = NULL;
> + uint vcpu_assoc_size;
>
> - vcpu_assoc[vcpu_assoc_size - 1] = cpu_to_be32(index);
> + vcpu_assoc = spapr_numa_get_vcpu_assoc(spapr, cpu, &vcpu_assoc_size);
>
> /* Advertise NUMA via ibm,associativity */
> return fdt_setprop(fdt, offset, "ibm,associativity",
> - vcpu_assoc, sizeof(vcpu_assoc));
> + vcpu_assoc, vcpu_assoc_size);
return fdt_setprop(fdt, offset, "ibm,associativity",
vcpu_assoc, VCPU_NUMA_ASSOC_SIZE * sizeof(uint32_t));
> }
>
>
