From f3f6d18417eb44ef393b23570d384d2778ef22dc Mon Sep 17 00:00:00 2001 From: Vaibhav Jain Date: Sat, 8 May 2021 10:06:42 +0530 Subject: [PATCH] powerpc/papr_scm: Reduce error severity if nvdimm stats inaccessible Currently drc_pmem_qeury_stats() generates a dev_err in case "Enable Performance Information Collection" feature is disabled from HMC or performance stats are not available for an nvdimm. The error is of the form below: papr_scm ibm,persistent-memory:ibm,pmemory@44104001: Failed to query performance stats, Err:-10 This error message confuses users as it implies a possible problem with the nvdimm even though its due to a disabled/unavailable feature. We fix this by explicitly handling the H_AUTHORITY and H_UNSUPPORTED errors from the H_SCM_PERFORMANCE_STATS hcall. In case of H_AUTHORITY error an info message is logged instead of an error, saying that "Permission denied while accessing performance stats" and an EPERM error is returned back. In case of H_UNSUPPORTED error we return a EOPNOTSUPP error back from drc_pmem_query_stats() indicating that performance stats-query operation is not supported on this nvdimm. Fixes: 2d02bf835e57 ("powerpc/papr_scm: Fetch nvdimm performance stats from PHYP") Signed-off-by: Vaibhav Jain Reviewed-by: Ira Weiny Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210508043642.114076-1-vaibhav@linux.ibm.com --- arch/powerpc/platforms/pseries/papr_scm.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/arch/powerpc/platforms/pseries/papr_scm.c b/arch/powerpc/platforms/pseries/papr_scm.c index ef26fe4..e2b69cc 100644 --- a/arch/powerpc/platforms/pseries/papr_scm.c +++ b/arch/powerpc/platforms/pseries/papr_scm.c @@ -310,6 +310,13 @@ static ssize_t drc_pmem_query_stats(struct papr_scm_priv *p, dev_err(&p->pdev->dev, "Unknown performance stats, Err:0x%016lX\n", ret[0]); return -ENOENT; + } else if (rc == H_AUTHORITY) { + dev_info(&p->pdev->dev, + "Permission denied while accessing performance stats"); + return -EPERM; + } else if (rc == H_UNSUPPORTED) { + dev_dbg(&p->pdev->dev, "Performance stats unsupported\n"); + return -EOPNOTSUPP; } else if (rc != H_SUCCESS) { dev_err(&p->pdev->dev, "Failed to query performance stats, Err:%lld\n", rc); -- 2.7.4