[PATCH v7 07/11] arm_mpam: propagate MSC access errors for mpam_reprogram_ris_partid()
From: Andre Przywara
Date: Fri Jul 31 2026 - 13:41:04 EST
Allow the mpam_reprogram_ris_partid() function check for and return
errors, and propagate MSC read and write errors from the lower level up.
This also covers the callers of this function: mpam_reset_ris() and
apply_config().
Signed-off-by: Andre Przywara <andre.przywara@xxxxxxx>
---
drivers/resctrl/mpam_devices.c | 136 ++++++++++++++++++++++-----------
1 file changed, 93 insertions(+), 43 deletions(-)
diff --git a/drivers/resctrl/mpam_devices.c b/drivers/resctrl/mpam_devices.c
index 38450c55e45e..32088ad1d67e 100644
--- a/drivers/resctrl/mpam_devices.c
+++ b/drivers/resctrl/mpam_devices.c
@@ -1601,7 +1601,7 @@ void mpam_msmon_reset_mbwu(struct mpam_component *comp, struct mon_cfg *ctx)
}
}
-static void mpam_reset_msc_bitmap(struct mpam_msc *msc, u16 reg, u16 wd)
+static int mpam_reset_msc_bitmap(struct mpam_msc *msc, u16 reg, u16 wd)
{
u32 num_words, msb;
u32 bm = ~0;
@@ -1610,15 +1610,19 @@ static void mpam_reset_msc_bitmap(struct mpam_msc *msc, u16 reg, u16 wd)
lockdep_assert_held(&msc->part_sel_lock);
if (wd == 0)
- return;
+ return 0;
/*
* Write all ~0 to all but the last 32bit-word, which may
* have fewer bits...
*/
num_words = DIV_ROUND_UP(wd, 32);
- for (i = 0; i < num_words - 1; i++, reg += sizeof(bm))
- __mpam_write_reg(msc, reg, bm);
+ for (i = 0; i < num_words - 1; i++, reg += sizeof(bm)) {
+ int ret = __mpam_write_reg(msc, reg, bm);
+
+ if (ret)
+ return ret;
+ }
/*
* ....and then the last (maybe) partial 32bit word. When wd is a
@@ -1626,7 +1630,7 @@ static void mpam_reset_msc_bitmap(struct mpam_msc *msc, u16 reg, u16 wd)
*/
msb = (wd - 1) % 32;
bm = GENMASK(msb, 0);
- __mpam_write_reg(msc, reg, bm);
+ return __mpam_write_reg(msc, reg, bm);
}
static void mpam_apply_t241_erratum(struct mpam_msc_ris *ris, u16 partid)
@@ -1699,8 +1703,8 @@ static u16 mpam_wa_t241_calc_min_from_max(struct mpam_props *props,
}
/* Called via IPI. Call while holding an SRCU reference */
-static void mpam_reprogram_ris_partid(struct mpam_msc_ris *ris, u16 partid,
- struct mpam_config *cfg)
+static int mpam_reprogram_ris_partid(struct mpam_msc_ris *ris, u16 partid,
+ struct mpam_config *cfg)
{
u32 pri_val = 0;
u16 cmax = MPAMCFG_CMAX_CMAX;
@@ -1708,34 +1712,53 @@ static void mpam_reprogram_ris_partid(struct mpam_msc_ris *ris, u16 partid,
struct mpam_props *rprops = &ris->props;
u16 dspri = GENMASK(rprops->dspri_wd, 0);
u16 intpri = GENMASK(rprops->intpri_wd, 0);
+ int ret;
- mutex_lock(&msc->part_sel_lock);
- __mpam_part_sel(ris->ris_idx, partid, msc);
+ guard(mutex)(&msc->part_sel_lock);
+ ret = __mpam_part_sel(ris->ris_idx, partid, msc);
+ if (ret)
+ return ret;
if (mpam_has_feature(mpam_feat_partid_nrw, rprops)) {
/* Update the intpartid mapping */
- mpam_write_partsel_reg(msc, INTPARTID,
- MPAMCFG_INTPARTID_INTERNAL | partid);
+ ret = mpam_write_partsel_reg(msc, INTPARTID,
+ MPAMCFG_INTPARTID_INTERNAL | partid);
+ if (ret)
+ return ret;
/*
* Then switch to the 'internal' partid to update the
* configuration.
*/
- __mpam_intpart_sel(ris->ris_idx, partid, msc);
+ ret = __mpam_intpart_sel(ris->ris_idx, partid, msc);
+ if (ret)
+ return ret;
}
if (mpam_has_feature(mpam_feat_cpor_part, rprops)) {
- if (mpam_has_feature(mpam_feat_cpor_part, cfg))
- mpam_write_partsel_reg(msc, CPBM, cfg->cpbm);
- else
- mpam_reset_msc_bitmap(msc, MPAMCFG_CPBM, rprops->cpbm_wd);
+ if (mpam_has_feature(mpam_feat_cpor_part, cfg)) {
+ ret = mpam_write_partsel_reg(msc, CPBM, cfg->cpbm);
+ if (ret)
+ return ret;
+ } else {
+ ret = mpam_reset_msc_bitmap(msc, MPAMCFG_CPBM,
+ rprops->cpbm_wd);
+ if (ret)
+ return ret;
+ }
}
if (mpam_has_feature(mpam_feat_mbw_part, rprops)) {
- if (mpam_has_feature(mpam_feat_mbw_part, cfg))
- mpam_reset_msc_bitmap(msc, MPAMCFG_MBW_PBM, rprops->mbw_pbm_bits);
- else
- mpam_write_partsel_reg(msc, MBW_PBM, cfg->mbw_pbm);
+ if (mpam_has_feature(mpam_feat_mbw_part, cfg)) {
+ ret = mpam_reset_msc_bitmap(msc, MPAMCFG_MBW_PBM,
+ rprops->mbw_pbm_bits);
+ if (ret)
+ return ret;
+ } else {
+ ret = mpam_write_partsel_reg(msc, MBW_PBM, cfg->mbw_pbm);
+ if (ret)
+ return ret;
+ }
}
if (mpam_has_feature(mpam_feat_mbw_min, rprops)) {
@@ -1748,27 +1771,47 @@ static void mpam_reprogram_ris_partid(struct mpam_msc_ris *ris, u16 partid,
val = max(val, min);
}
- mpam_write_partsel_reg(msc, MBW_MIN, val);
+ ret = mpam_write_partsel_reg(msc, MBW_MIN, val);
+ if (ret)
+ return ret;
}
if (mpam_has_feature(mpam_feat_mbw_max, rprops)) {
- if (mpam_has_feature(mpam_feat_mbw_max, cfg))
- mpam_write_partsel_reg(msc, MBW_MAX, cfg->mbw_max);
- else
- mpam_write_partsel_reg(msc, MBW_MAX, MPAMCFG_MBW_MAX_MAX);
+ if (mpam_has_feature(mpam_feat_mbw_max, cfg)) {
+ ret = mpam_write_partsel_reg(msc, MBW_MAX, cfg->mbw_max);
+ if (ret)
+ return ret;
+ } else {
+ ret = mpam_write_partsel_reg(msc, MBW_MAX,
+ MPAMCFG_MBW_MAX_MAX);
+ if (ret)
+ return ret;
+ }
}
- if (mpam_has_feature(mpam_feat_mbw_prop, rprops))
- mpam_write_partsel_reg(msc, MBW_PROP, 0);
+ if (mpam_has_feature(mpam_feat_mbw_prop, rprops)) {
+ ret = mpam_write_partsel_reg(msc, MBW_PROP, 0);
+ if (ret)
+ return ret;
+ }
- if (mpam_has_feature(mpam_feat_cmax_cmax, rprops))
- mpam_write_partsel_reg(msc, CMAX, cmax);
+ if (mpam_has_feature(mpam_feat_cmax_cmax, rprops)) {
+ ret = mpam_write_partsel_reg(msc, CMAX, cmax);
+ if (ret)
+ return ret;
+ }
- if (mpam_has_feature(mpam_feat_cmax_cmin, rprops))
- mpam_write_partsel_reg(msc, CMIN, 0);
+ if (mpam_has_feature(mpam_feat_cmax_cmin, rprops)) {
+ ret = mpam_write_partsel_reg(msc, CMIN, 0);
+ if (ret)
+ return ret;
+ }
- if (mpam_has_feature(mpam_feat_cmax_cassoc, rprops))
- mpam_write_partsel_reg(msc, CASSOC, MPAMCFG_CASSOC_CASSOC);
+ if (mpam_has_feature(mpam_feat_cmax_cassoc, rprops)) {
+ ret = mpam_write_partsel_reg(msc, CASSOC, MPAMCFG_CASSOC_CASSOC);
+ if (ret)
+ return ret;
+ }
if (mpam_has_feature(mpam_feat_intpri_part, rprops) ||
mpam_has_feature(mpam_feat_dspri_part, rprops)) {
@@ -1783,12 +1826,14 @@ static void mpam_reprogram_ris_partid(struct mpam_msc_ris *ris, u16 partid,
if (mpam_has_feature(mpam_feat_dspri_part, rprops))
pri_val |= FIELD_PREP(MPAMCFG_PRI_DSPRI, dspri);
- mpam_write_partsel_reg(msc, PRI, pri_val);
+ ret = mpam_write_partsel_reg(msc, PRI, pri_val);
+ if (ret)
+ return ret;
}
mpam_quirk_post_config_change(ris, partid, cfg);
- mutex_unlock(&msc->part_sel_lock);
+ return 0;
}
/* Call with msc cfg_lock held */
@@ -1891,6 +1936,7 @@ static int mpam_reset_ris(void *arg)
u16 partid, partid_max;
struct mpam_config reset_cfg = {};
struct mpam_msc_ris *ris = arg;
+ int ret;
if (ris->in_reset_state)
return 0;
@@ -1898,8 +1944,11 @@ static int mpam_reset_ris(void *arg)
spin_lock(&partid_max_lock);
partid_max = mpam_partid_max;
spin_unlock(&partid_max_lock);
- for (partid = 0; partid <= partid_max; partid++)
- mpam_reprogram_ris_partid(ris, partid, &reset_cfg);
+ for (partid = 0; partid <= partid_max; partid++) {
+ ret = mpam_reprogram_ris_partid(ris, partid, &reset_cfg);
+ if (ret)
+ return ret;
+ }
return 0;
}
@@ -1938,9 +1987,8 @@ static int __write_config(void *arg)
{
struct mpam_write_config_arg *c = arg;
- mpam_reprogram_ris_partid(c->ris, c->partid, &c->comp->cfg[c->partid]);
-
- return 0;
+ return mpam_reprogram_ris_partid(c->ris, c->partid,
+ &c->comp->cfg[c->partid]);
}
static void mpam_reprogram_msc(struct mpam_msc *msc)
@@ -3088,6 +3136,7 @@ int mpam_apply_config(struct mpam_component *comp, u16 partid,
struct mpam_msc_ris *ris;
struct mpam_vmsc *vmsc;
struct mpam_msc *msc;
+ int ret;
lockdep_assert_cpus_held();
@@ -3105,14 +3154,15 @@ int mpam_apply_config(struct mpam_component *comp, u16 partid,
srcu_read_lock_held(&mpam_srcu)) {
msc = vmsc->msc;
- mutex_lock(&msc->cfg_lock);
+ guard(mutex)(&msc->cfg_lock);
list_for_each_entry_srcu(ris, &vmsc->ris, vmsc_list,
srcu_read_lock_held(&mpam_srcu)) {
arg.ris = ris;
- mpam_touch_msc(msc, __write_config, &arg);
+ ret = mpam_touch_msc(msc, __write_config, &arg);
+ if (ret)
+ return ret;
ris->in_reset_state = false;
}
- mutex_unlock(&msc->cfg_lock);
}
return 0;
--
2.43.0