Re: [PATCH v4 4/8] perf: arm_spe: Drop BIT() and use FIELD_GET/PREP accessors

From: Anshuman Khandual
Date: Tue Jan 10 2023 - 03:37:38 EST




On 1/10/23 00:56, Rob Herring wrote:
> Now that generated sysregs are in place, update the register field
> accesses. The use of BIT() is no longer needed with the new defines. Use
> FIELD_GET and FIELD_PREP instead of open coding masking and shifting.
>
> No functional change.
>
> Tested-by: James Clark <james.clark@xxxxxxx>
> Signed-off-by: Rob Herring <robh@xxxxxxxxxx>

Reviewed-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>

> ---
> v4:
> - Rebase on v6.2-rc1
> v3:
> - no change
> ---
> drivers/perf/arm_spe_pmu.c | 70 ++++++++++++++++++++++------------------------
> 1 file changed, 34 insertions(+), 36 deletions(-)
>
> diff --git a/drivers/perf/arm_spe_pmu.c b/drivers/perf/arm_spe_pmu.c
> index 814ed18346b6..9b4bd72087ea 100644
> --- a/drivers/perf/arm_spe_pmu.c
> +++ b/drivers/perf/arm_spe_pmu.c
> @@ -283,18 +283,18 @@ static u64 arm_spe_event_to_pmscr(struct perf_event *event)
> struct perf_event_attr *attr = &event->attr;
> u64 reg = 0;
>
> - reg |= ATTR_CFG_GET_FLD(attr, ts_enable) << PMSCR_EL1_TS_SHIFT;
> - reg |= ATTR_CFG_GET_FLD(attr, pa_enable) << PMSCR_EL1_PA_SHIFT;
> - reg |= ATTR_CFG_GET_FLD(attr, pct_enable) << PMSCR_EL1_PCT_SHIFT;
> + reg |= FIELD_PREP(PMSCR_EL1_TS, ATTR_CFG_GET_FLD(attr, ts_enable));
> + reg |= FIELD_PREP(PMSCR_EL1_PA, ATTR_CFG_GET_FLD(attr, pa_enable));
> + reg |= FIELD_PREP(PMSCR_EL1_PCT, ATTR_CFG_GET_FLD(attr, pct_enable));
>
> if (!attr->exclude_user)
> - reg |= BIT(PMSCR_EL1_E0SPE_SHIFT);
> + reg |= PMSCR_EL1_E0SPE;
>
> if (!attr->exclude_kernel)
> - reg |= BIT(PMSCR_EL1_E1SPE_SHIFT);
> + reg |= PMSCR_EL1_E1SPE;
>
> if (get_spe_event_has_cx(event))
> - reg |= BIT(PMSCR_EL1_CX_SHIFT);
> + reg |= PMSCR_EL1_CX;
>
> return reg;
> }
> @@ -322,7 +322,7 @@ static u64 arm_spe_event_to_pmsirr(struct perf_event *event)
>
> arm_spe_event_sanitise_period(event);
>
> - reg |= ATTR_CFG_GET_FLD(attr, jitter) << PMSIRR_EL1_RND_SHIFT;
> + reg |= FIELD_PREP(PMSIRR_EL1_RND, ATTR_CFG_GET_FLD(attr, jitter));
> reg |= event->hw.sample_period;
>
> return reg;
> @@ -333,18 +333,18 @@ static u64 arm_spe_event_to_pmsfcr(struct perf_event *event)
> struct perf_event_attr *attr = &event->attr;
> u64 reg = 0;
>
> - reg |= ATTR_CFG_GET_FLD(attr, load_filter) << PMSFCR_EL1_LD_SHIFT;
> - reg |= ATTR_CFG_GET_FLD(attr, store_filter) << PMSFCR_EL1_ST_SHIFT;
> - reg |= ATTR_CFG_GET_FLD(attr, branch_filter) << PMSFCR_EL1_B_SHIFT;
> + reg |= FIELD_PREP(PMSFCR_EL1_LD, ATTR_CFG_GET_FLD(attr, load_filter));
> + reg |= FIELD_PREP(PMSFCR_EL1_ST, ATTR_CFG_GET_FLD(attr, store_filter));
> + reg |= FIELD_PREP(PMSFCR_EL1_B, ATTR_CFG_GET_FLD(attr, branch_filter));
>
> if (reg)
> - reg |= BIT(PMSFCR_EL1_FT_SHIFT);
> + reg |= PMSFCR_EL1_FT;
>
> if (ATTR_CFG_GET_FLD(attr, event_filter))
> - reg |= BIT(PMSFCR_EL1_FE_SHIFT);
> + reg |= PMSFCR_EL1_FE;
>
> if (ATTR_CFG_GET_FLD(attr, min_latency))
> - reg |= BIT(PMSFCR_EL1_FL_SHIFT);
> + reg |= PMSFCR_EL1_FL;
>
> return reg;
> }
> @@ -358,8 +358,7 @@ static u64 arm_spe_event_to_pmsevfr(struct perf_event *event)
> static u64 arm_spe_event_to_pmslatfr(struct perf_event *event)
> {
> struct perf_event_attr *attr = &event->attr;
> - return ATTR_CFG_GET_FLD(attr, min_latency)
> - << PMSLATFR_EL1_MINLAT_SHIFT;
> + return FIELD_PREP(PMSLATFR_EL1_MINLAT, ATTR_CFG_GET_FLD(attr, min_latency));
> }
>
> static void arm_spe_pmu_pad_buf(struct perf_output_handle *handle, int len)
> @@ -511,7 +510,7 @@ static void arm_spe_perf_aux_output_begin(struct perf_output_handle *handle,
> limit = buf->snapshot ? arm_spe_pmu_next_snapshot_off(handle)
> : arm_spe_pmu_next_off(handle);
> if (limit)
> - limit |= BIT(PMBLIMITR_EL1_E_SHIFT);
> + limit |= PMBLIMITR_EL1_E;
>
> limit += (u64)buf->base;
> base = (u64)buf->base + PERF_IDX2OFF(handle->head, buf);
> @@ -570,23 +569,23 @@ arm_spe_pmu_buf_get_fault_act(struct perf_output_handle *handle)
>
> /* Service required? */
> pmbsr = read_sysreg_s(SYS_PMBSR_EL1);
> - if (!(pmbsr & BIT(PMBSR_EL1_S_SHIFT)))
> + if (!FIELD_GET(PMBSR_EL1_S, pmbsr))
> return SPE_PMU_BUF_FAULT_ACT_SPURIOUS;
>
> /*
> * If we've lost data, disable profiling and also set the PARTIAL
> * flag to indicate that the last record is corrupted.
> */
> - if (pmbsr & BIT(PMBSR_EL1_DL_SHIFT))
> + if (FIELD_GET(PMBSR_EL1_DL, pmbsr))
> perf_aux_output_flag(handle, PERF_AUX_FLAG_TRUNCATED |
> PERF_AUX_FLAG_PARTIAL);
>
> /* Report collisions to userspace so that it can up the period */
> - if (pmbsr & BIT(PMBSR_EL1_COLL_SHIFT))
> + if (FIELD_GET(PMBSR_EL1_COLL, pmbsr))
> perf_aux_output_flag(handle, PERF_AUX_FLAG_COLLISION);
>
> /* We only expect buffer management events */
> - switch (FIELD_GET(PMBSR_EL1_EC_MASK, pmbsr)) {
> + switch (FIELD_GET(PMBSR_EL1_EC, pmbsr)) {
> case PMBSR_EL1_EC_BUF:
> /* Handled below */
> break;
> @@ -716,23 +715,22 @@ static int arm_spe_pmu_event_init(struct perf_event *event)
> return -EINVAL;
>
> reg = arm_spe_event_to_pmsfcr(event);
> - if ((reg & BIT(PMSFCR_EL1_FE_SHIFT)) &&
> + if ((FIELD_GET(PMSFCR_EL1_FE, reg)) &&
> !(spe_pmu->features & SPE_PMU_FEAT_FILT_EVT))
> return -EOPNOTSUPP;
>
> - if ((reg & BIT(PMSFCR_EL1_FT_SHIFT)) &&
> + if ((FIELD_GET(PMSFCR_EL1_FT, reg)) &&
> !(spe_pmu->features & SPE_PMU_FEAT_FILT_TYP))
> return -EOPNOTSUPP;
>
> - if ((reg & BIT(PMSFCR_EL1_FL_SHIFT)) &&
> + if ((FIELD_GET(PMSFCR_EL1_FL, reg)) &&
> !(spe_pmu->features & SPE_PMU_FEAT_FILT_LAT))
> return -EOPNOTSUPP;
>
> set_spe_event_has_cx(event);
> reg = arm_spe_event_to_pmscr(event);
> if (!perfmon_capable() &&
> - (reg & (BIT(PMSCR_EL1_PA_SHIFT) |
> - BIT(PMSCR_EL1_PCT_SHIFT))))
> + (reg & (PMSCR_EL1_PA | PMSCR_EL1_PCT)))
> return -EACCES;
>
> return 0;
> @@ -970,14 +968,14 @@ static void __arm_spe_pmu_dev_probe(void *info)
>
> /* Read PMBIDR first to determine whether or not we have access */
> reg = read_sysreg_s(SYS_PMBIDR_EL1);
> - if (reg & BIT(PMBIDR_EL1_P_SHIFT)) {
> + if (FIELD_GET(PMBIDR_EL1_P, reg)) {
> dev_err(dev,
> "profiling buffer owned by higher exception level\n");
> return;
> }
>
> /* Minimum alignment. If it's out-of-range, then fail the probe */
> - fld = (reg & PMBIDR_EL1_ALIGN_MASK) >> PMBIDR_EL1_ALIGN_SHIFT;
> + fld = FIELD_GET(PMBIDR_EL1_ALIGN, reg);
> spe_pmu->align = 1 << fld;
> if (spe_pmu->align > SZ_2K) {
> dev_err(dev, "unsupported PMBIDR.Align [%d] on CPU %d\n",
> @@ -987,26 +985,26 @@ static void __arm_spe_pmu_dev_probe(void *info)
>
> /* It's now safe to read PMSIDR and figure out what we've got */
> reg = read_sysreg_s(SYS_PMSIDR_EL1);
> - if (reg & BIT(PMSIDR_EL1_FE_SHIFT))
> + if (FIELD_GET(PMSIDR_EL1_FE, reg))
> spe_pmu->features |= SPE_PMU_FEAT_FILT_EVT;
>
> - if (reg & BIT(PMSIDR_EL1_FT_SHIFT))
> + if (FIELD_GET(PMSIDR_EL1_FT, reg))
> spe_pmu->features |= SPE_PMU_FEAT_FILT_TYP;
>
> - if (reg & BIT(PMSIDR_EL1_FL_SHIFT))
> + if (FIELD_GET(PMSIDR_EL1_FL, reg))
> spe_pmu->features |= SPE_PMU_FEAT_FILT_LAT;
>
> - if (reg & BIT(PMSIDR_EL1_ARCHINST_SHIFT))
> + if (FIELD_GET(PMSIDR_EL1_ARCHINST, reg))
> spe_pmu->features |= SPE_PMU_FEAT_ARCH_INST;
>
> - if (reg & BIT(PMSIDR_EL1_LDS_SHIFT))
> + if (FIELD_GET(PMSIDR_EL1_LDS, reg))
> spe_pmu->features |= SPE_PMU_FEAT_LDS;
>
> - if (reg & BIT(PMSIDR_EL1_ERND_SHIFT))
> + if (FIELD_GET(PMSIDR_EL1_ERND, reg))
> spe_pmu->features |= SPE_PMU_FEAT_ERND;
>
> /* This field has a spaced out encoding, so just use a look-up */
> - fld = (reg & PMSIDR_EL1_INTERVAL_MASK) >> PMSIDR_EL1_INTERVAL_SHIFT;
> + fld = FIELD_GET(PMSIDR_EL1_INTERVAL, reg);
> switch (fld) {
> case 0:
> spe_pmu->min_period = 256;
> @@ -1038,7 +1036,7 @@ static void __arm_spe_pmu_dev_probe(void *info)
> }
>
> /* Maximum record size. If it's out-of-range, then fail the probe */
> - fld = (reg & PMSIDR_EL1_MAXSIZE_MASK) >> PMSIDR_EL1_MAXSIZE_SHIFT;
> + fld = FIELD_GET(PMSIDR_EL1_MAXSIZE, reg);
> spe_pmu->max_record_sz = 1 << fld;
> if (spe_pmu->max_record_sz > SZ_2K || spe_pmu->max_record_sz < 16) {
> dev_err(dev, "unsupported PMSIDR_EL1.MaxSize [%d] on CPU %d\n",
> @@ -1046,7 +1044,7 @@ static void __arm_spe_pmu_dev_probe(void *info)
> return;
> }
>
> - fld = (reg & PMSIDR_EL1_COUNTSIZE_MASK) >> PMSIDR_EL1_COUNTSIZE_SHIFT;
> + fld = FIELD_GET(PMSIDR_EL1_COUNTSIZE, reg);
> switch (fld) {
> default:
> dev_warn(dev, "unknown PMSIDR_EL1.CountSize [%d]; assuming 2\n",
>