diff options
Diffstat (limited to 'drivers/target/iscsi/iscsi_target.c')
| -rw-r--r-- | drivers/target/iscsi/iscsi_target.c | 77 |
1 files changed, 74 insertions, 3 deletions
diff --git a/drivers/target/iscsi/iscsi_target.c b/drivers/target/iscsi/iscsi_target.c index 2c54c5d8412d..6fe6a6bab3f4 100644 --- a/drivers/target/iscsi/iscsi_target.c +++ b/drivers/target/iscsi/iscsi_target.c @@ -702,13 +702,19 @@ static int __init iscsi_target_init_module(void) if (!iscsit_global->ts_bitmap) goto configfs_out; + if (!zalloc_cpumask_var(&iscsit_global->allowed_cpumask, GFP_KERNEL)) { + pr_err("Unable to allocate iscsit_global->allowed_cpumask\n"); + goto bitmap_out; + } + cpumask_setall(iscsit_global->allowed_cpumask); + lio_qr_cache = kmem_cache_create("lio_qr_cache", sizeof(struct iscsi_queue_req), __alignof__(struct iscsi_queue_req), 0, NULL); if (!lio_qr_cache) { pr_err("Unable to kmem_cache_create() for" " lio_qr_cache\n"); - goto bitmap_out; + goto cpumask_out; } lio_dr_cache = kmem_cache_create("lio_dr_cache", @@ -753,6 +759,8 @@ dr_out: kmem_cache_destroy(lio_dr_cache); qr_out: kmem_cache_destroy(lio_qr_cache); +cpumask_out: + free_cpumask_var(iscsit_global->allowed_cpumask); bitmap_out: vfree(iscsit_global->ts_bitmap); configfs_out: @@ -782,6 +790,7 @@ static void __exit iscsi_target_cleanup_module(void) target_unregister_template(&iscsi_ops); + free_cpumask_var(iscsit_global->allowed_cpumask); vfree(iscsit_global->ts_bitmap); kfree(iscsit_global); } @@ -3587,6 +3596,11 @@ static int iscsit_send_reject( void iscsit_thread_get_cpumask(struct iscsi_conn *conn) { int ord, cpu; + cpumask_t conn_allowed_cpumask; + + cpumask_and(&conn_allowed_cpumask, iscsit_global->allowed_cpumask, + cpu_online_mask); + /* * bitmap_id is assigned from iscsit_global->ts_bitmap from * within iscsit_start_kthreads() @@ -3595,8 +3609,9 @@ void iscsit_thread_get_cpumask(struct iscsi_conn *conn) * iSCSI connection's RX/TX threads will be scheduled to * execute upon. */ - ord = conn->bitmap_id % cpumask_weight(cpu_online_mask); - for_each_online_cpu(cpu) { + cpumask_clear(conn->conn_cpumask); + ord = conn->bitmap_id % cpumask_weight(&conn_allowed_cpumask); + for_each_cpu(cpu, &conn_allowed_cpumask) { if (ord-- == 0) { cpumask_set_cpu(cpu, conn->conn_cpumask); return; @@ -3609,6 +3624,62 @@ void iscsit_thread_get_cpumask(struct iscsi_conn *conn) cpumask_setall(conn->conn_cpumask); } +static void iscsit_thread_reschedule(struct iscsi_conn *conn) +{ + /* + * If iscsit_global->allowed_cpumask modified, reschedule iSCSI + * connection's RX/TX threads update conn->allowed_cpumask. + */ + if (!cpumask_equal(iscsit_global->allowed_cpumask, + conn->allowed_cpumask)) { + iscsit_thread_get_cpumask(conn); + conn->conn_tx_reset_cpumask = 1; + conn->conn_rx_reset_cpumask = 1; + cpumask_copy(conn->allowed_cpumask, + iscsit_global->allowed_cpumask); + } +} + +void iscsit_thread_check_cpumask( + struct iscsi_conn *conn, + struct task_struct *p, + int mode) +{ + /* + * The TX and RX threads maybe call iscsit_thread_check_cpumask() + * at the same time. The RX thread might be faster and return from + * iscsit_thread_reschedule() with conn_rx_reset_cpumask set to 0. + * Then the TX thread sets it back to 1. + * The next time the RX thread loops, it sees conn_rx_reset_cpumask + * set to 1 and calls set_cpus_allowed_ptr() again and set it to 0. + */ + iscsit_thread_reschedule(conn); + + /* + * mode == 1 signals iscsi_target_tx_thread() usage. + * mode == 0 signals iscsi_target_rx_thread() usage. + */ + if (mode == 1) { + if (!conn->conn_tx_reset_cpumask) + return; + } else { + if (!conn->conn_rx_reset_cpumask) + return; + } + + /* + * Update the CPU mask for this single kthread so that + * both TX and RX kthreads are scheduled to run on the + * same CPU. + */ + set_cpus_allowed_ptr(p, conn->conn_cpumask); + if (mode == 1) + conn->conn_tx_reset_cpumask = 0; + else + conn->conn_rx_reset_cpumask = 0; +} +EXPORT_SYMBOL(iscsit_thread_check_cpumask); + int iscsit_immediate_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state) { |