Re: [PATCH RESEND 1/2] MIPS: cacheinfo: Add missing VCache

[Jiaxun Yang]

在 2020/8/22 0:55, Thomas Bogendoerfer 写道:

On Thu, Aug 20, 2020 at 08:42:49AM +0800, Jiaxun Yang wrote:

Victim Cache is defined by Loongson as per-core unified
private Cache.
Add this into cacheinfo and make cache levels selfincrement
instead of hardcode levels.

Signed-off-by: Jiaxun Yang <jiaxun.y...@flygoat.com>
---
  arch/mips/kernel/cacheinfo.c | 34 ++++++++++++++++++++++++++--------
  1 file changed, 26 insertions(+), 8 deletions(-)

diff --git a/arch/mips/kernel/cacheinfo.c b/arch/mips/kernel/cacheinfo.c
index 47312c529410..83548331ee94 100644
--- a/arch/mips/kernel/cacheinfo.c
+++ b/arch/mips/kernel/cacheinfo.c
@@ -35,6 +35,11 @@ static int __init_cache_level(unsigned int cpu)

leaves += (c->icache.waysize) ? 2 : 1; + if (c->vcache.waysize) {

+               levels++;
+               leaves++;
+       }
+
        if (c->scache.waysize) {
                levels++;
                leaves++;
@@ -74,25 +79,38 @@ static int __populate_cache_leaves(unsigned int cpu)
        struct cpuinfo_mips *c = &current_cpu_data;
        struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
        struct cacheinfo *this_leaf = this_cpu_ci->info_list;
+       int level = 1;

if (c->icache.waysize) {

-               /* L1 caches are per core */
+               /* D/I caches are per core */
                fill_cpumask_siblings(cpu, &this_leaf->shared_cpu_map);
-               populate_cache(dcache, this_leaf, 1, CACHE_TYPE_DATA);
+               populate_cache(dcache, this_leaf, level, CACHE_TYPE_DATA);
                fill_cpumask_siblings(cpu, &this_leaf->shared_cpu_map);
-               populate_cache(icache, this_leaf, 1, CACHE_TYPE_INST);
+               populate_cache(icache, this_leaf, level, CACHE_TYPE_INST);
+               level++;
        } else {
-               populate_cache(dcache, this_leaf, 1, CACHE_TYPE_UNIFIED);
+               populate_cache(dcache, this_leaf, level, CACHE_TYPE_UNIFIED);
+               level++;
+       }
+
+       if (c->vcache.waysize) {

why can't we insert vcache as level 4 and leave the rest of the file
alone ?

Hi Thomas,

Oops I forgot this patch.

Because  VCache is physicaly placed between Scache and I/D Cache as per
core chahe, it will confuse userspace program otherwise.

Also I do think the level should be continues.

Thanks

- Jiaxun

Thomas.