Messages in this thread Patch in this message | | | Date | Sun, 15 May 2022 22:50:55 -0700 | Subject | [PATCH] x86/resctrl: fix min_cbm_bits for AMD | From | Stephane Eranian <> |
| |
AMD supports cbm with no bits set as reflected in rdt_init_res_defs_amd() by:
r->cache.arch_has_empty_bitmaps = true;
However given the unified code in cbm_validate(), checking for
val == 0 && !arch_has_empty_bitmaps
is not enough because you also have in cbm_validate(): if ((zero_bit - first_bit) < r->cache.min_cbm_bits)
Default value for if r->cache.min_cbm_bits = 1
Leading to:
$ cd /sys/fs/resctrl $ mkdir foo $ cd foo $ echo L3:0=0 > schemata -bash: echo: write error: Invalid argument
Patch initializes r->cache.min_cbm_bits to 0 for AMD.
Signed-off-by: Stephane Eranian <eranian@google.com> --- arch/x86/kernel/cpu/resctrl/core.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c index bb1c3f5f60c8..14782361ebb7 100644 --- a/arch/x86/kernel/cpu/resctrl/core.c +++ b/arch/x86/kernel/cpu/resctrl/core.c @@ -897,6 +897,7 @@ static __init void rdt_init_res_defs_amd(void) r->cache.arch_has_sparse_bitmaps = true; r->cache.arch_has_empty_bitmaps = true; r->cache.arch_has_per_cpu_cfg = true; + r->cache.min_cbm_bits = 0; } else if (r->rid == RDT_RESOURCE_MBA) { hw_res->msr_base = MSR_IA32_MBA_BW_BASE; hw_res->msr_update = mba_wrmsr_amd; -- 2.36.0.550.gb090851708-goog
| |