[PATCH v2 08/10] x86/resctrl: Merge AMD/Intel parse_bw() calls

From: James Morse
Date: Thu Apr 30 2020 - 13:04:49 EST


Now that we've explained arch_needs_linear to resctrl, the parse_bw()
calls are almost the same between AMD and Intel.

The difference is '!is_mba_sc()', which is not checked on AMD. This
will always be true on AMD CPUs as mba_sc cannot be enabled as
is_mba_linear() is false.

Removing this duplication means user-space visible behaviour and
error messages are not validated or generated in different places.

CC: Babu Moger <Babu.Moger@xxxxxxx>
Signed-off-by: James Morse <james.morse@xxxxxxx>
---
arch/x86/kernel/cpu/resctrl/core.c | 3 +-
arch/x86/kernel/cpu/resctrl/ctrlmondata.c | 57 +----------------------
arch/x86/kernel/cpu/resctrl/internal.h | 6 +--
3 files changed, 5 insertions(+), 61 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 40186c54b05d..7a6a6303fc05 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -168,6 +168,7 @@ struct rdt_resource rdt_resources_all[] = {
.name = "MB",
.domains = domain_init(RDT_RESOURCE_MBA),
.cache_level = 3,
+ .parse_ctrlval = parse_bw,
.format_str = "%d=%*u",
.fflags = RFTYPE_RES_MB,
},
@@ -926,7 +927,6 @@ static __init void rdt_init_res_defs_intel(void)
else if (r->rid == RDT_RESOURCE_MBA) {
r->msr_base = MSR_IA32_MBA_THRTL_BASE;
r->msr_update = mba_wrmsr_intel;
- r->parse_ctrlval = parse_bw_intel;
}
}
}
@@ -946,7 +946,6 @@ static __init void rdt_init_res_defs_amd(void)
else if (r->rid == RDT_RESOURCE_MBA) {
r->msr_base = MSR_IA32_MBA_BW_BASE;
r->msr_update = mba_wrmsr_amd;
- r->parse_ctrlval = parse_bw_amd;
}
}
}
diff --git a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
index db8e6c0cadb1..c983efddb537 100644
--- a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
+++ b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
@@ -21,59 +21,6 @@
#include <linux/slab.h>
#include "internal.h"

-/*
- * Check whether MBA bandwidth percentage value is correct. The value is
- * checked against the minimum and maximum bandwidth values specified by
- * the hardware. The allocated bandwidth percentage is rounded to the next
- * control step available on the hardware.
- */
-static bool bw_validate_amd(char *buf, unsigned long *data,
- struct rdt_resource *r)
-{
- unsigned long bw;
- int ret;
-
- /* temporary: always false on AMD */
- if (!r->membw.delay_linear && r->membw.arch_needs_linear) {
- rdt_last_cmd_puts("No support for non-linear MB domains\n");
- return false;
- }
-
- ret = kstrtoul(buf, 10, &bw);
- if (ret) {
- rdt_last_cmd_printf("Non-decimal digit in MB value %s\n", buf);
- return false;
- }
-
- if (bw < r->membw.min_bw || bw > r->default_ctrl) {
- rdt_last_cmd_printf("MB value %ld out of range [%d,%d]\n", bw,
- r->membw.min_bw, r->default_ctrl);
- return false;
- }
-
- *data = roundup(bw, (unsigned long)r->membw.bw_gran);
- return true;
-}
-
-int parse_bw_amd(struct rdt_parse_data *data, struct rdt_resource *r,
- struct rdt_domain *d)
-{
- unsigned long bw_val;
-
- if (d->have_new_ctrl) {
- rdt_last_cmd_printf("Duplicate domain %d\n", d->id);
- return -EINVAL;
- }
-
- if (!bw_validate_amd(data->buf, &bw_val, r))
- return -EINVAL;
-
- d->new_ctrl = bw_val;
- d->have_new_ctrl = true;
-
- return 0;
-}
-
/*
* Check whether MBA bandwidth percentage value is correct. The value is
* checked against the minimum and max bandwidth values specified by the
@@ -110,8 +57,8 @@ static bool bw_validate(char *buf, unsigned long *data, struct rdt_resource *r)
return true;
}

-int parse_bw_intel(struct rdt_parse_data *data, struct rdt_resource *r,
- struct rdt_domain *d)
+int parse_bw(struct rdt_parse_data *data, struct rdt_resource *r,
+ struct rdt_domain *d)
{
unsigned long bw_val;

diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 215be9957acf..c8d84aec62d3 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -462,10 +462,8 @@ struct rdt_resource {

int parse_cbm(struct rdt_parse_data *data, struct rdt_resource *r,
struct rdt_domain *d);
-int parse_bw_intel(struct rdt_parse_data *data, struct rdt_resource *r,
- struct rdt_domain *d);
-int parse_bw_amd(struct rdt_parse_data *data, struct rdt_resource *r,
- struct rdt_domain *d);
+int parse_bw(struct rdt_parse_data *data, struct rdt_resource *r,
+ struct rdt_domain *d);

extern struct mutex rdtgroup_mutex;

--
2.26.1