tjh.dev / kernel
Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel os linux
1
fork

Configure Feed

Select the types of activity you want to include in your feed.

perf/x86/core: Do not set bit width for unavailable counters

Not all x86 processors have fixed counters. It may also be the case that
a processor has only fixed counters and no general-purpose counters. Set
the bit widths corresponding to each counter type only if such counters
are available.

Fixes: b3d9468a8bd2 ("perf, x86: Expose perf capability to other modules")
Signed-off-by: Sandipan Das <sandipan.das@amd.com>
Co-developed-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Signed-off-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Signed-off-by: Mingwei Zhang <mizhang@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Xudong Hao <xudong.hao@intel.com>
Link: https://patch.msgid.link/20251206001720.468579-11-seanjc@google.com

authored by

Sandipan Das and committed by
Peter Zijlstra b456a6ba 560ac136

+2 -2
+2 -2
arch/x86/events/core.c
··· 3105 3105 cap->version = x86_pmu.version; 3106 3106 cap->num_counters_gp = x86_pmu_num_counters(NULL); 3107 3107 cap->num_counters_fixed = x86_pmu_num_counters_fixed(NULL); 3108 - cap->bit_width_gp = x86_pmu.cntval_bits; 3109 - cap->bit_width_fixed = x86_pmu.cntval_bits; 3108 + cap->bit_width_gp = cap->num_counters_gp ? x86_pmu.cntval_bits : 0; 3109 + cap->bit_width_fixed = cap->num_counters_fixed ? x86_pmu.cntval_bits : 0; 3110 3110 cap->events_mask = (unsigned int)x86_pmu.events_maskl; 3111 3111 cap->events_mask_len = x86_pmu.events_mask_len; 3112 3112 cap->pebs_ept = x86_pmu.pebs_ept;