perf/x86: Use macros to replace magic numbers in attr_rdpmc

Replace magic numbers in attr_rdpmc with macros to improve readability
and make their meanings clearer for users.

Signed-off-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/20260114011750.350569-7-dapeng1.mi@linux.intel.com

diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c
index 0ecac9495d74c82831d35cf1831e1846a5d448b4..c2717cb5034f62fc05f5d393de664291741212d5 100644 (file)
--- a/arch/x86/events/core.c
+++ b/arch/x86/events/core.c
@@ -2163,7 +2163,8 @@ static int __init init_hw_perf_events(void)
 
        pr_cont("%s PMU driver.\n", x86_pmu.name);
 
-       x86_pmu.attr_rdpmc = 1; /* enable userspace RDPMC usage by default */
+       /* enable userspace RDPMC usage by default */
+       x86_pmu.attr_rdpmc = X86_USER_RDPMC_CONDITIONAL_ENABLE;
 
        for (quirk = x86_pmu.quirks; quirk; quirk = quirk->next)
                quirk->func();
@@ -2643,12 +2644,12 @@ static ssize_t set_attr_rdpmc(struct device *cdev,
                 */
                if (val == 0)
                        static_branch_inc(&rdpmc_never_available_key);
-               else if (x86_pmu.attr_rdpmc == 0)
+               else if (x86_pmu.attr_rdpmc == X86_USER_RDPMC_NEVER_ENABLE)
                        static_branch_dec(&rdpmc_never_available_key);
 
                if (val == 2)
                        static_branch_inc(&rdpmc_always_available_key);
-               else if (x86_pmu.attr_rdpmc == 2)
+               else if (x86_pmu.attr_rdpmc == X86_USER_RDPMC_ALWAYS_ENABLE)
                        static_branch_dec(&rdpmc_always_available_key);
 
                on_each_cpu(cr4_update_pce, NULL, 1);

diff --git a/arch/x86/events/intel/p6.c b/arch/x86/events/intel/p6.c
index 6e41de355bd89c82b302180404cc2c35c78f50bc..fb991e0ac6142efeb33da52bd6bdf0e209e54305 100644 (file)
--- a/arch/x86/events/intel/p6.c
+++ b/arch/x86/events/intel/p6.c
@@ -243,7 +243,7 @@ static __init void p6_pmu_rdpmc_quirk(void)
                 */
                pr_warn("Userspace RDPMC support disabled due to a CPU erratum\n");
                x86_pmu.attr_rdpmc_broken = 1;
-               x86_pmu.attr_rdpmc = 0;
+               x86_pmu.attr_rdpmc = X86_USER_RDPMC_NEVER_ENABLE;
        }
 }
 

diff --git a/arch/x86/events/perf_event.h b/arch/x86/events/perf_event.h
index f7caabc5d4870b1ed4b80a751dcf8b0561cc2242..24a81d2916e9d3f3a70e81fb656196465e43af3f 100644 (file)
--- a/arch/x86/events/perf_event.h
+++ b/arch/x86/events/perf_event.h
@@ -187,6 +187,13 @@ struct amd_nb {
         (1ULL << PERF_REG_X86_R14)   | \
         (1ULL << PERF_REG_X86_R15))
 
+/* user space rdpmc control values */
+enum {
+       X86_USER_RDPMC_NEVER_ENABLE             = 0,
+       X86_USER_RDPMC_CONDITIONAL_ENABLE       = 1,
+       X86_USER_RDPMC_ALWAYS_ENABLE            = 2,
+};
+
 /*
  * Per register state.
  */