[PATCH 2/5] Unroll INIT_TASK() in init/init_task.c

From: David Howells
Date: Fri Nov 24 2017 - 10:32:19 EST


It's no longer necessary to have an INIT_TASK() macro, and this can be
unrolled into the one place it is now used.

Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
---

include/linux/init_task.h | 87 ++-------------------------------------------
init/init_task.c | 85 +++++++++++++++++++++++++++++++++++++++++++-
2 files changed, 87 insertions(+), 85 deletions(-)

diff --git a/include/linux/init_task.h b/include/linux/init_task.h
index 30a89b99a5af..9711611b831d 100644
--- a/include/linux/init_task.h
+++ b/include/linux/init_task.h
@@ -218,91 +218,12 @@ extern struct cred init_cred;
#define INIT_TASK_SECURITY
#endif

-/*
- * INIT_TASK is used to set up the first task table, touch at
- * your own risk!. Base=0, limit=0x1fffff (=2MB)
- */
-#define INIT_TASK(tsk) \
-{ \
- INIT_TASK_TI(tsk) \
- .state = 0, \
- .stack = init_stack, \
- .usage = ATOMIC_INIT(2), \
- .flags = PF_KTHREAD, \
- .prio = MAX_PRIO-20, \
- .static_prio = MAX_PRIO-20, \
- .normal_prio = MAX_PRIO-20, \
- .policy = SCHED_NORMAL, \
- .cpus_allowed = CPU_MASK_ALL, \
- .nr_cpus_allowed= NR_CPUS, \
- .mm = NULL, \
- .active_mm = &init_mm, \
- .restart_block = { \
- .fn = do_no_restart_syscall, \
- }, \
- .se = { \
- .group_node = LIST_HEAD_INIT(tsk.se.group_node), \
- }, \
- .rt = { \
- .run_list = LIST_HEAD_INIT(tsk.rt.run_list), \
- .time_slice = RR_TIMESLICE, \
- }, \
- .tasks = LIST_HEAD_INIT(tsk.tasks), \
- INIT_PUSHABLE_TASKS(tsk) \
- INIT_CGROUP_SCHED(tsk) \
- .ptraced = LIST_HEAD_INIT(tsk.ptraced), \
- .ptrace_entry = LIST_HEAD_INIT(tsk.ptrace_entry), \
- .real_parent = &tsk, \
- .parent = &tsk, \
- .children = LIST_HEAD_INIT(tsk.children), \
- .sibling = LIST_HEAD_INIT(tsk.sibling), \
- .group_leader = &tsk, \
- RCU_POINTER_INITIALIZER(real_cred, &init_cred), \
- RCU_POINTER_INITIALIZER(cred, &init_cred), \
- .comm = INIT_TASK_COMM, \
- .thread = INIT_THREAD, \
- .fs = &init_fs, \
- .files = &init_files, \
- .signal = &init_signals, \
- .sighand = &init_sighand, \
- .nsproxy = &init_nsproxy, \
- .pending = { \
- .list = LIST_HEAD_INIT(tsk.pending.list), \
- .signal = {{0}}}, \
- .blocked = {{0}}, \
- .alloc_lock = __SPIN_LOCK_UNLOCKED(tsk.alloc_lock), \
- .journal_info = NULL, \
- INIT_CPU_TIMERS(tsk) \
- .pi_lock = __RAW_SPIN_LOCK_UNLOCKED(tsk.pi_lock), \
- .timer_slack_ns = 50000, /* 50 usec default slack */ \
- .pids = { \
- [PIDTYPE_PID] = INIT_PID_LINK(PIDTYPE_PID), \
- [PIDTYPE_PGID] = INIT_PID_LINK(PIDTYPE_PGID), \
- [PIDTYPE_SID] = INIT_PID_LINK(PIDTYPE_SID), \
- }, \
- .thread_group = LIST_HEAD_INIT(tsk.thread_group), \
- .thread_node = LIST_HEAD_INIT(init_signals.thread_head), \
- INIT_IDS \
- INIT_PERF_EVENTS(tsk) \
- INIT_TRACE_IRQFLAGS \
- INIT_LOCKDEP \
- INIT_FTRACE_GRAPH \
- INIT_TRACE_RECURSION \
- INIT_TASK_RCU_PREEMPT(tsk) \
- INIT_TASK_RCU_TASKS(tsk) \
- INIT_CPUSET_SEQ(tsk) \
- INIT_RT_MUTEXES(tsk) \
- INIT_PREV_CPUTIME(tsk) \
- INIT_VTIME(tsk) \
- INIT_NUMA_BALANCING(tsk) \
- INIT_KASAN(tsk) \
- INIT_LIVEPATCH(tsk) \
- INIT_TASK_SECURITY \
-}
-
-
/* Attach to the init_task data structure for proper alignment */
+#ifdef CONFIG_ARCH_TASK_STRUCT_ON_STACK
#define __init_task_data __attribute__((__section__(".data..init_task")))
+#else
+#define __init_task_data /**/
+#endif

/* Attach to the thread_info data structure for proper alignment */
#define __init_thread_info __attribute__((__section__(".data..init_thread_info")))
diff --git a/init/init_task.c b/init/init_task.c
index 2285aa42cbe1..7b2436f02dad 100644
--- a/init/init_task.c
+++ b/init/init_task.c
@@ -16,12 +16,93 @@
static struct signal_struct init_signals = INIT_SIGNALS(init_signals);
static struct sighand_struct init_sighand = INIT_SIGHAND(init_sighand);

-/* Initial task structure */
+
+/*
+ * Set up the first task table, touch at your own risk!. Base=0,
+ * limit=0x1fffff (=2MB)
+ */
struct task_struct init_task
#ifdef CONFIG_ARCH_TASK_STRUCT_ON_STACK
__init_task_data
#endif
- = INIT_TASK(init_task);
+= {
+ INIT_TASK_TI(init_task)
+ .state = 0,
+ .stack = init_stack,
+ .usage = ATOMIC_INIT(2),
+ .flags = PF_KTHREAD,
+ .prio = MAX_PRIO-20,
+ .static_prio = MAX_PRIO-20,
+ .normal_prio = MAX_PRIO-20,
+ .policy = SCHED_NORMAL,
+ .cpus_allowed = CPU_MASK_ALL,
+ .nr_cpus_allowed= NR_CPUS,
+ .mm = NULL,
+ .active_mm = &init_mm,
+ .restart_block = {
+ .fn = do_no_restart_syscall,
+ },
+ .se = {
+ .group_node = LIST_HEAD_INIT(init_task.se.group_node),
+ },
+ .rt = {
+ .run_list = LIST_HEAD_INIT(init_task.rt.run_list),
+ .time_slice = RR_TIMESLICE,
+ },
+ .tasks = LIST_HEAD_INIT(init_task.tasks),
+ INIT_PUSHABLE_TASKS(init_task)
+ INIT_CGROUP_SCHED(init_task)
+ .ptraced = LIST_HEAD_INIT(init_task.ptraced),
+ .ptrace_entry = LIST_HEAD_INIT(init_task.ptrace_entry),
+ .real_parent = &init_task,
+ .parent = &init_task,
+ .children = LIST_HEAD_INIT(init_task.children),
+ .sibling = LIST_HEAD_INIT(init_task.sibling),
+ .group_leader = &init_task,
+ RCU_POINTER_INITIALIZER(real_cred, &init_cred),
+ RCU_POINTER_INITIALIZER(cred, &init_cred),
+ .comm = INIT_TASK_COMM,
+ .thread = INIT_THREAD,
+ .fs = &init_fs,
+ .files = &init_files,
+ .signal = &init_signals,
+ .sighand = &init_sighand,
+ .nsproxy = &init_nsproxy,
+ .pending = {
+ .list = LIST_HEAD_INIT(init_task.pending.list),
+ .signal = {{0}}
+ },
+ .blocked = {{0}},
+ .alloc_lock = __SPIN_LOCK_UNLOCKED(init_task.alloc_lock),
+ .journal_info = NULL,
+ INIT_CPU_TIMERS(init_task)
+ .pi_lock = __RAW_SPIN_LOCK_UNLOCKED(init_task.pi_lock),
+ .timer_slack_ns = 50000, /* 50 usec default slack */
+ .pids = {
+ [PIDTYPE_PID] = INIT_PID_LINK(PIDTYPE_PID),
+ [PIDTYPE_PGID] = INIT_PID_LINK(PIDTYPE_PGID),
+ [PIDTYPE_SID] = INIT_PID_LINK(PIDTYPE_SID),
+ },
+ .thread_group = LIST_HEAD_INIT(init_task.thread_group),
+ .thread_node = LIST_HEAD_INIT(init_signals.thread_head),
+ INIT_IDS
+ INIT_PERF_EVENTS(init_task)
+ INIT_TRACE_IRQFLAGS
+ INIT_LOCKDEP
+ INIT_FTRACE_GRAPH
+ INIT_TRACE_RECURSION
+ INIT_TASK_RCU_PREEMPT(init_task)
+ INIT_TASK_RCU_TASKS(init_task)
+ INIT_CPUSET_SEQ(init_task)
+ INIT_RT_MUTEXES(init_task)
+ INIT_PREV_CPUTIME(init_task)
+ INIT_VTIME(init_task)
+ INIT_NUMA_BALANCING(init_task)
+ INIT_KASAN(init_task)
+ INIT_LIVEPATCH(init_task)
+ INIT_TASK_SECURITY
+};
+
EXPORT_SYMBOL(init_task);

/*