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perf/x86/rapl: Fix the error checking order

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After the commit b4943b8bfc ("perf/x86/rapl: Add core energy counter
support for AMD CPUs"), the default "perf record"/"perf top" command is
broken in systems where there isn't a PMU registered for type
PERF_TYPE_RAW.

This is due to the change in order of error checks in rapl_pmu_event_init()
Due to which we return -EINVAL instead of -ENOENT, when we reach here from
the fallback loop in perf_init_event().

Move the "PMU and event type match" back to the beginning of the function
so that we return -ENOENT early on.

Closes: https://lore.kernel.org/all/uv7mz6vew2bzgre5jdpmwldxljp5djzmuiksqdcdwipfm4zm7w@ribobcretidk/
Fixes: b4943b8bfc ("perf/x86/rapl: Add core energy counter support for AMD CPUs")
Reported-by: Koichiro Den <koichiro.den@canonical.com>
Signed-off-by: Dhananjay Ugwekar <dhananjay.ugwekar@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20250129080513.30353-1-dhananjay.ugwekar@amd.com
This commit is contained in:
Dhananjay Ugwekar
2025-01-29 08:05:14 +00:00
committed by Peter Zijlstra
parent 2014c95afe
commit 469c76a83b
1 changed files with 4 additions and 8 deletions
Download Patch File Download Diff File Expand all files Collapse all files
arch/x86/events/rapl.c
+4 -8
View File
@@ -370,6 +370,10 @@ static int rapl_pmu_event_init(struct perf_event *event)
unsigned int rapl_pmu_idx;
struct rapl_pmus *rapl_pmus;
/* only look at RAPL events */
if (event->attr.type != event->pmu->type)
return -ENOENT;
/* unsupported modes and filters */
if (event->attr.sample_period) /* no sampling */
return -EINVAL;
@@ -387,10 +391,6 @@ static int rapl_pmu_event_init(struct perf_event *event)
rapl_pmus_scope = rapl_pmus->pmu.scope;
if (rapl_pmus_scope == PERF_PMU_SCOPE_PKG || rapl_pmus_scope == PERF_PMU_SCOPE_DIE) {
/* only look at RAPL package events */
if (event->attr.type != rapl_pmus_pkg->pmu.type)
return -ENOENT;
cfg = array_index_nospec((long)cfg, NR_RAPL_PKG_DOMAINS + 1);
if (!cfg || cfg >= NR_RAPL_PKG_DOMAINS + 1)
return -EINVAL;
@@ -398,10 +398,6 @@ static int rapl_pmu_event_init(struct perf_event *event)
bit = cfg - 1;
event->hw.event_base = rapl_model->rapl_pkg_msrs[bit].msr;
} else if (rapl_pmus_scope == PERF_PMU_SCOPE_CORE) {
/* only look at RAPL core events */
if (event->attr.type != rapl_pmus_core->pmu.type)
return -ENOENT;
cfg = array_index_nospec((long)cfg, NR_RAPL_CORE_DOMAINS + 1);
if (!cfg || cfg >= NR_RAPL_PKG_DOMAINS + 1)
return -EINVAL;