1. 03 Aug, 2020 1 commit
  2. 31 Jul, 2020 2 commits
    • Vaibhav Jain's avatar
      powerpc/papr_scm: Add support for fetching nvdimm 'fuel-gauge' metric · af0870c4
      Vaibhav Jain authored
      We add support for reporting 'fuel-gauge' NVDIMM metric via
      PAPR_PDSM_HEALTH pdsm payload. 'fuel-gauge' metric indicates the usage
      life remaining of a papr-scm compatible NVDIMM. PHYP exposes this
      metric via the H_SCM_PERFORMANCE_STATS.
      
      The metric value is returned from the pdsm by extending the return
      payload 'struct nd_papr_pdsm_health' without breaking the ABI. A new
      field 'dimm_fuel_gauge' to hold the metric value is introduced at the
      end of the payload struct and its presence is indicated by by
      extension flag PDSM_DIMM_HEALTH_RUN_GAUGE_VALID.
      
      The patch introduces a new function papr_pdsm_fuel_gauge() that is
      called from papr_pdsm_health(). If fetching NVDIMM performance stats
      is supported then 'papr_pdsm_fuel_gauge()' allocated an output buffer
      large enough to hold the performance stat and passes it to
      drc_pmem_query_stats() that issues the HCALL to PHYP. The return value
      of the stat is then populated in the 'struct
      nd_papr_pdsm_health.dimm_fuel_gauge' field with extension flag
      'PDSM_DIMM_HEALTH_RUN_GAUGE_VALID' set in 'struct
      nd_papr_pdsm_health.extension_flags'
      Signed-off-by: default avatarVaibhav Jain <vaibhav@linux.ibm.com>
      Reviewed-by: default avatarAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
      Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
      Link: https://lore.kernel.org/r/20200731064153.182203-3-vaibhav@linux.ibm.com
      af0870c4
    • Vaibhav Jain's avatar
      powerpc/papr_scm: Fetch nvdimm performance stats from PHYP · 2d02bf83
      Vaibhav Jain authored
      Update papr_scm.c to query dimm performance statistics from PHYP via
      H_SCM_PERFORMANCE_STATS hcall and export them to user-space as PAPR
      specific NVDIMM attribute 'perf_stats' in sysfs. The patch also
      provide a sysfs ABI documentation for the stats being reported and
      their meanings.
      
      During NVDIMM probe time in papr_scm_nvdimm_init() a special variant
      of H_SCM_PERFORMANCE_STATS hcall is issued to check if collection of
      performance statistics is supported or not. If successful then a PHYP
      returns a maximum possible buffer length needed to read all
      performance stats. This returned value is stored in a per-nvdimm
      attribute 'stat_buffer_len'.
      
      The layout of request buffer for reading NVDIMM performance stats from
      PHYP is defined in 'struct papr_scm_perf_stats' and 'struct
      papr_scm_perf_stat'. These structs are used in newly introduced
      drc_pmem_query_stats() that issues the H_SCM_PERFORMANCE_STATS hcall.
      
      The sysfs access function perf_stats_show() uses value
      'stat_buffer_len' to allocate a buffer large enough to hold all
      possible NVDIMM performance stats and passes it to
      drc_pmem_query_stats() to populate. Finally statistics reported in the
      buffer are formatted into the sysfs access function output buffer.
      Signed-off-by: default avatarVaibhav Jain <vaibhav@linux.ibm.com>
      Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
      Link: https://lore.kernel.org/r/20200731064153.182203-2-vaibhav@linux.ibm.com
      2d02bf83
  3. 30 Jul, 2020 13 commits
  4. 29 Jul, 2020 24 commits