This patch adds support for retrieving a singled NVDIMM performance stat from PHYP via PDSM GET_PERF_STAT_VERSION. A new uapi 'struct nd_pdsm_get_perf_stat' is introduced that holds a single performance stat and is populated by newly introduced papr_scm_get_perf_stat() by issuing an H_SCM_PERFORMANCE_STATS to PHYP.
Signed-off-by: Vaibhav Jain <[email protected]> --- arch/powerpc/include/uapi/asm/papr_scm_pdsm.h | 12 +++ arch/powerpc/platforms/pseries/papr_scm.c | 74 +++++++++++++++++++ 2 files changed, 86 insertions(+) diff --git a/arch/powerpc/include/uapi/asm/papr_scm_pdsm.h b/arch/powerpc/include/uapi/asm/papr_scm_pdsm.h index 2db4ffdff285..473c4bbddb2f 100644 --- a/arch/powerpc/include/uapi/asm/papr_scm_pdsm.h +++ b/arch/powerpc/include/uapi/asm/papr_scm_pdsm.h @@ -116,6 +116,7 @@ enum papr_scm_pdsm { PAPR_SCM_PDSM_HEALTH, PAPR_SCM_PDSM_FETCH_PERF_STATS, PAPR_SCM_PDSM_READ_PERF_STATS, + PAPR_SCM_PDSM_GET_PERF_STAT, PAPR_SCM_PDSM_MAX, }; @@ -218,4 +219,15 @@ struct nd_pdsm_read_perf_stats_v1 { #define nd_pdsm_read_perf_stats nd_pdsm_read_perf_stats_v1 #define ND_PDSM_READ_PERF_STATS_VERSION 1 +/* + * Fetch the value of single nvdimm performance stat id of which is + * stored in 'stat.id' + */ +struct nd_pdsm_get_perf_stat_v1 { + struct nd_pdsm_perf_stat stat; +} __packed; + +#define nd_pdsm_get_perf_stat nd_pdsm_get_perf_stat_v1 +#define ND_PDSM_GET_PERF_STAT_VERSION 1 + #endif /* _UAPI_ASM_POWERPC_PAPR_SCM_PDSM_H_ */ diff --git a/arch/powerpc/platforms/pseries/papr_scm.c b/arch/powerpc/platforms/pseries/papr_scm.c index 06744d7fe727..284d04f0a094 100644 --- a/arch/powerpc/platforms/pseries/papr_scm.c +++ b/arch/powerpc/platforms/pseries/papr_scm.c @@ -525,6 +525,77 @@ static int is_cmd_valid(struct nvdimm *nvdimm, unsigned int cmd, void *buf, return 0; } +static int papr_scm_get_perf_stat(struct papr_scm_priv *p, + struct nd_pdsm_cmd_pkg *pkg) +{ + int rc; + struct nd_pdsm_get_perf_stat *stat = + (struct nd_pdsm_get_perf_stat *)pdsm_cmd_to_payload(pkg); + const size_t copysize = sizeof(struct nd_pdsm_get_perf_stat); + struct papr_scm_perf_stats *stats_req; + ssize_t stat_size; + + /* + * If the requested payload version is greater than one we know + * about, return the payload version we know about and let + * caller/userspace handle. + */ + if (pkg->payload_version > ND_PDSM_GET_PERF_STAT_VERSION) + pkg->payload_version = ND_PDSM_GET_PERF_STAT_VERSION; + + if (pkg->hdr.nd_size_out < copysize) { + dev_dbg(&p->pdev->dev, "Truncated payload (%u). Expected (%lu)", + pkg->hdr.nd_size_out, copysize); + rc = -ENOSPC; + goto out; + } + + if (!READ_ONCE(p->len_stat_buffer)) { + dev_dbg(&p->pdev->dev, "Perf stat: req for unsupported device"); + rc = -ENOENT; + goto out; + } + + /* Allocate and setup a PERFORMANCE_STATS request buffer */ + stat_size = sizeof(struct papr_scm_perf_stats) + + sizeof(struct papr_scm_perf_stat); + stats_req = kzalloc(stat_size, GFP_KERNEL); + if (!stats_req) { + dev_err(&p->pdev->dev, "Perf stat: Unable to allocate memory\n"); + rc = -ENOMEM; + goto out; + } + + /* Copy the single request statistic_id into the request buffer */ + memcpy(&stats_req->scm_statistics[0].statistic_id, &stat->stat.id, + sizeof(stats_req->scm_statistics[0].statistic_id)); + + /* Fetch the stat from PHYP */ + rc = drc_pmem_query_stats(p, stats_req, stat_size, 1, NULL); + if (rc) + goto out; + + /* Copy the value of stat to the return payload */ + memcpy(&stat->stat.id, &stats_req->scm_statistics[0].statistic_id, + sizeof(stat->stat.id)); + stat->stat.val = stats_req->scm_statistics[0].statistic_value; + + pkg->hdr.nd_fw_size = copysize; + + dev_dbg(&p->pdev->dev, "Copying payload size=%u version=0x%x\n", + pkg->hdr.nd_fw_size, pkg->payload_version); + +out: + /* + * Put the error in out package and return success from function + * so that errors if any are propogated back to userspace. + */ + pkg->cmd_status = rc; + dev_dbg(&p->pdev->dev, "completion code = %d\n", rc); + + return 0; +} + /* * Read the contents of dimm performance statistics buffer at the given * 'in_offset' and copy 'in_length' number of bytes to the pkg payload. @@ -755,6 +826,9 @@ static int papr_scm_service_pdsm(struct papr_scm_priv *p, case PAPR_SCM_PDSM_READ_PERF_STATS: return papr_scm_read_perf_stats(p, call_pkg); + case PAPR_SCM_PDSM_GET_PERF_STAT: + return papr_scm_get_perf_stat(p, call_pkg); + default: dev_dbg(&p->pdev->dev, "Unsupported PDSM request 0x%llx\n", call_pkg->hdr.nd_command); -- 2.26.2 _______________________________________________ Linux-nvdimm mailing list -- [email protected] To unsubscribe send an email to [email protected]
