Use existing 'zvol_threads' variable for kstat

Author: arun-kv

include/os/windows/zfs/sys/kstat_windows.h

@@ -260,7 +260,7 @@ extern uint64_t zfs_initialize_value;
 extern int zfs_autoimport_disable;
 extern int zfs_removal_suspend_progress;
 extern int cpu_avx_supported;
-extern int zvol_io_threads;
+extern int zvol_threads;
 
 int  kstat_windows_init(void *);
 void kstat_windows_fini(void);

module/os/windows/zfs/arc_os.c

@@ -695,8 +695,7 @@ arc_kstat_update_windows(kstat_t *ksp, int rw)
 		zfs_arc_p_min_shift = ks->arc_zfs_arc_p_min_shift.value.ui64;
 		zfs_arc_average_blocksize =
 		    ks->arc_zfs_arc_average_blocksize.value.ui64;
-		zvol_io_threads =
-		    ks->zvol_io_threads.value.ui32;
+		zvol_threads = ks->zvol_io_threads.value.ui32;
 
 #ifdef _KERNEL
 		if (ks->zfs_total_memory_limit.value.ui64 > total_memory &&
@@ -731,7 +730,7 @@ arc_kstat_update_windows(kstat_t *ksp, int rw)
 		ks->arc_zfs_arc_p_min_shift.value.ui64 = zfs_arc_p_min_shift;
 		ks->arc_zfs_arc_average_blocksize.value.ui64 =
 		    zfs_arc_average_blocksize;
-		ks->zvol_io_threads.value.ui32 = zvol_io_threads;
+		ks->zvol_io_threads.value.ui32 = zvol_threads;
 
 #ifdef _KERNEL
 		ks->zfs_total_memory_limit.value.ui64 = total_memory;

module/os/windows/zfs/zfs_kstat_windows.c

@@ -383,9 +383,6 @@ windows_kstat_update(kstat_t *ksp, int rw)
 		    ks->zfs_removal_suspend_progress.value.i32;
 		cpu_avx_supported =
 		    ks->cpu_avx_supported.value.ui32;
-		zvol_io_threads =
-		    ks->zvol_io_threads.value.ui32;
-
 	} else {
 
 		/* kstat READ */
@@ -575,7 +572,7 @@ windows_kstat_update(kstat_t *ksp, int rw)
 		ks->cpu_avx_supported.value.ui32 =
 		    cpu_avx_supported;
 		ks->zvol_io_threads.value.ui32 =
-		    zvol_io_threads;
+		    zvol_threads;
 	}
 	arc_kstat_update_windows(ksp, rw);
 	return (0);

module/os/windows/zfs/zvol_os.c

@@ -45,8 +45,7 @@ static uint32_t zvol_major = ZVOL_MAJOR;
 unsigned int zvol_request_sync = 0;
 unsigned int zvol_prefetch_bytes = (128 * 1024);
 unsigned long zvol_max_discard_blocks = 16384;
-unsigned int zvol_threads = 32;
-int zvol_io_threads = 0;
+int zvol_threads = 0;
 
 taskq_t *zvol_taskq;
 
@@ -1029,21 +1028,19 @@ const static zvol_platform_ops_t zvol_windows_ops = {
 int
 zvol_init(void)
 {
-	if (!zvol_io_threads)
-		zvol_io_threads = zvol_threads;
-
-	zvol_threads = zvol_io_threads;
-
-	int threads = MIN(MAX(zvol_threads, 1), 1024);
+	int threads = MIN(MAX((zvol_threads ? zvol_threads: boot_ncpus), 1), 1024);
 
 	KdPrintEx((DPFLTR_IHVDRIVER_ID, DPFLTR_ERROR_LEVEL,
-		"%s: zvol taskq threads %d regvalue: %d\n", __func__, threads, zvol_io_threads));
+		"%s: number of zvol taskq threads to be created: %d, registry value: %d ncpus: %d\n",
+		__func__, threads, zvol_threads, boot_ncpus));
 	zvol_taskq = taskq_create(ZVOL_DRIVER, threads, maxclsyspri,
 	    threads * 2, INT_MAX, TASKQ_PREPOPULATE | TASKQ_DYNAMIC);
 	if (zvol_taskq == NULL) {
 		return (-ENOMEM);
 	}
 
+	zvol_threads = threads; // Update it so that kstat gets the current value
+
 	zvol_init_impl();
 	zvol_register_ops(&zvol_windows_ops);
 	return (0);