drivers: perf: Fix wrong put_cpu() placement

Unfortunately, the wrong patch version was merged which places the
put_cpu() after enabling a static key, which is not safe as pointed by
Will [1], so move put_cpu() before to avoid this.

Fixes: 2840dad ("drivers: perf: Fix smp_processor_id() use in preemptible code")
Reported-by: Atish Patra <[email protected]>
Link: https://lore.kernel.org/all/20240827125335.GD4772@willie-the-truck/ [1]
Signed-off-by: Alexandre Ghiti <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Palmer Dabbelt <[email protected]>

Author: Alexandre Ghiti

drivers/perf/riscv_pmu_sbi.c

@@ -1393,8 +1393,9 @@ static int pmu_sbi_device_probe(struct platform_device *pdev)
 			goto out_unregister;
 
 		cpu = get_cpu();
-
 		ret = pmu_sbi_snapshot_setup(pmu, cpu);
+		put_cpu();
+
 		if (ret) {
 			/* Snapshot is an optional feature. Continue if not available */
 			pmu_sbi_snapshot_free(pmu);
@@ -1408,7 +1409,6 @@ static int pmu_sbi_device_probe(struct platform_device *pdev)
 			 */
 			static_branch_enable(&sbi_pmu_snapshot_available);
 		}
-		put_cpu();
 	}
 
 	register_sysctl("kernel", sbi_pmu_sysctl_table);