diff options
| -rw-r--r-- | drivers/resctrl/mpam_devices.c | 109 | ||||
| -rw-r--r-- | drivers/resctrl/mpam_internal.h | 3 |
2 files changed, 112 insertions, 0 deletions
diff --git a/drivers/resctrl/mpam_devices.c b/drivers/resctrl/mpam_devices.c index f9ac88bf06b7..4bd4d57a3baa 100644 --- a/drivers/resctrl/mpam_devices.c +++ b/drivers/resctrl/mpam_devices.c @@ -7,6 +7,7 @@ #include <linux/atomic.h> #include <linux/arm_mpam.h> #include <linux/bitfield.h> +#include <linux/bitmap.h> #include <linux/cacheinfo.h> #include <linux/cpu.h> #include <linux/cpumask.h> @@ -752,8 +753,104 @@ static int mpam_msc_hw_probe(struct mpam_msc *msc) return 0; } +static void mpam_reset_msc_bitmap(struct mpam_msc *msc, u16 reg, u16 wd) +{ + u32 num_words, msb; + u32 bm = ~0; + int i; + + lockdep_assert_held(&msc->part_sel_lock); + + if (wd == 0) + return; + + /* + * 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); + + /* + * ....and then the last (maybe) partial 32bit word. When wd is a + * multiple of 32, msb should be 31 to write a full 32bit word. + */ + msb = (wd - 1) % 32; + bm = GENMASK(msb, 0); + __mpam_write_reg(msc, reg, bm); +} + +static void mpam_reset_ris_partid(struct mpam_msc_ris *ris, u16 partid) +{ + struct mpam_msc *msc = ris->vmsc->msc; + struct mpam_props *rprops = &ris->props; + + WARN_ON_ONCE(!srcu_read_lock_held((&mpam_srcu))); + + mutex_lock(&msc->part_sel_lock); + __mpam_part_sel(ris->ris_idx, partid, msc); + + if (mpam_has_feature(mpam_feat_cpor_part, rprops)) + mpam_reset_msc_bitmap(msc, MPAMCFG_CPBM, rprops->cpbm_wd); + + if (mpam_has_feature(mpam_feat_mbw_part, rprops)) + mpam_reset_msc_bitmap(msc, MPAMCFG_MBW_PBM, rprops->mbw_pbm_bits); + + if (mpam_has_feature(mpam_feat_mbw_min, rprops)) + mpam_write_partsel_reg(msc, MBW_MIN, 0); + + if (mpam_has_feature(mpam_feat_mbw_max, rprops)) + mpam_write_partsel_reg(msc, MBW_MAX, MPAMCFG_MBW_MAX_MAX); + + mutex_unlock(&msc->part_sel_lock); +} + +static void mpam_reset_ris(struct mpam_msc_ris *ris) +{ + u16 partid, partid_max; + + WARN_ON_ONCE(!srcu_read_lock_held((&mpam_srcu))); + + if (ris->in_reset_state) + return; + + spin_lock(&partid_max_lock); + partid_max = mpam_partid_max; + spin_unlock(&partid_max_lock); + for (partid = 0; partid <= partid_max; partid++) + mpam_reset_ris_partid(ris, partid); +} + +static void mpam_reset_msc(struct mpam_msc *msc, bool online) +{ + struct mpam_msc_ris *ris; + + list_for_each_entry_srcu(ris, &msc->ris, msc_list, srcu_read_lock_held(&mpam_srcu)) { + mpam_reset_ris(ris); + + /* + * Set in_reset_state when coming online. The reset state + * for non-zero partid may be lost while the CPUs are offline. + */ + ris->in_reset_state = online; + } +} + static int mpam_cpu_online(unsigned int cpu) { + struct mpam_msc *msc; + + guard(srcu)(&mpam_srcu); + list_for_each_entry_srcu(msc, &mpam_all_msc, all_msc_list, + srcu_read_lock_held(&mpam_srcu)) { + if (!cpumask_test_cpu(cpu, &msc->accessibility)) + continue; + + if (atomic_fetch_inc(&msc->online_refs) == 0) + mpam_reset_msc(msc, true); + } + return 0; } @@ -792,6 +889,18 @@ static int mpam_discovery_cpu_online(unsigned int cpu) static int mpam_cpu_offline(unsigned int cpu) { + struct mpam_msc *msc; + + guard(srcu)(&mpam_srcu); + list_for_each_entry_srcu(msc, &mpam_all_msc, all_msc_list, + srcu_read_lock_held(&mpam_srcu)) { + if (!cpumask_test_cpu(cpu, &msc->accessibility)) + continue; + + if (atomic_dec_and_test(&msc->online_refs)) + mpam_reset_msc(msc, false); + } + return 0; } diff --git a/drivers/resctrl/mpam_internal.h b/drivers/resctrl/mpam_internal.h index 4749ac223adc..dec485cd8a91 100644 --- a/drivers/resctrl/mpam_internal.h +++ b/drivers/resctrl/mpam_internal.h @@ -5,6 +5,7 @@ #define MPAM_INTERNAL_H #include <linux/arm_mpam.h> +#include <linux/atomic.h> #include <linux/bitmap.h> #include <linux/cpumask.h> #include <linux/io.h> @@ -45,6 +46,7 @@ struct mpam_msc { enum mpam_msc_iface iface; u32 nrdy_usec; cpumask_t accessibility; + atomic_t online_refs; /* * probe_lock is only taken during discovery. After discovery these @@ -198,6 +200,7 @@ struct mpam_msc_ris { u8 ris_idx; u64 idr; struct mpam_props props; + bool in_reset_state; cpumask_t affinity; |