kernel-ark/include/linux/init_task.h
Zach Brown 20dcae3243 [PATCH] aio: remove kioctx from mm_struct
Sync iocbs have a life cycle that don't need a kioctx.  Their retrying, if
any, is done in the context of their owner who has allocated them on the
stack.

The sole user of a sync iocb's ctx reference was aio_complete() checking for
an elevated iocb ref count that could never happen.  No path which grabs an
iocb ref has access to sync iocbs.

If we were to implement sync iocb cancelation it would be done by the owner of
the iocb using its on-stack reference.

Removing this chunk from aio_complete allows us to remove the entire kioctx
instance from mm_struct, reducing its size by a third.  On a i386 testing box
the slab size went from 768 to 504 bytes and from 5 to 8 per page.

Signed-off-by: Zach Brown <zach.brown@oracle.com>
Acked-by: Benjamin LaHaise <bcrl@kvack.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-13 18:14:16 -08:00

136 lines
3.6 KiB
C

#ifndef _LINUX__INIT_TASK_H
#define _LINUX__INIT_TASK_H
#include <linux/file.h>
#include <linux/rcupdate.h>
#define INIT_FDTABLE \
{ \
.max_fds = NR_OPEN_DEFAULT, \
.max_fdset = __FD_SETSIZE, \
.next_fd = 0, \
.fd = &init_files.fd_array[0], \
.close_on_exec = &init_files.close_on_exec_init, \
.open_fds = &init_files.open_fds_init, \
.rcu = RCU_HEAD_INIT, \
.free_files = NULL, \
.next = NULL, \
}
#define INIT_FILES \
{ \
.count = ATOMIC_INIT(1), \
.file_lock = SPIN_LOCK_UNLOCKED, \
.fdt = &init_files.fdtab, \
.fdtab = INIT_FDTABLE, \
.close_on_exec_init = { { 0, } }, \
.open_fds_init = { { 0, } }, \
.fd_array = { NULL, } \
}
#define INIT_KIOCTX(name, which_mm) \
{ \
.users = ATOMIC_INIT(1), \
.dead = 0, \
.mm = &which_mm, \
.user_id = 0, \
.next = NULL, \
.wait = __WAIT_QUEUE_HEAD_INITIALIZER(name.wait), \
.ctx_lock = SPIN_LOCK_UNLOCKED, \
.reqs_active = 0U, \
.max_reqs = ~0U, \
}
#define INIT_MM(name) \
{ \
.mm_rb = RB_ROOT, \
.pgd = swapper_pg_dir, \
.mm_users = ATOMIC_INIT(2), \
.mm_count = ATOMIC_INIT(1), \
.mmap_sem = __RWSEM_INITIALIZER(name.mmap_sem), \
.page_table_lock = SPIN_LOCK_UNLOCKED, \
.mmlist = LIST_HEAD_INIT(name.mmlist), \
.cpu_vm_mask = CPU_MASK_ALL, \
}
#define INIT_SIGNALS(sig) { \
.count = ATOMIC_INIT(1), \
.wait_chldexit = __WAIT_QUEUE_HEAD_INITIALIZER(sig.wait_chldexit),\
.shared_pending = { \
.list = LIST_HEAD_INIT(sig.shared_pending.list), \
.signal = {{0}}}, \
.posix_timers = LIST_HEAD_INIT(sig.posix_timers), \
.cpu_timers = INIT_CPU_TIMERS(sig.cpu_timers), \
.rlim = INIT_RLIMITS, \
}
#define INIT_SIGHAND(sighand) { \
.count = ATOMIC_INIT(1), \
.action = { { { .sa_handler = NULL, } }, }, \
.siglock = SPIN_LOCK_UNLOCKED, \
}
extern struct group_info init_groups;
/*
* 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) \
{ \
.state = 0, \
.thread_info = &init_thread_info, \
.usage = ATOMIC_INIT(2), \
.flags = 0, \
.lock_depth = -1, \
.prio = MAX_PRIO-20, \
.static_prio = MAX_PRIO-20, \
.policy = SCHED_NORMAL, \
.cpus_allowed = CPU_MASK_ALL, \
.mm = NULL, \
.active_mm = &init_mm, \
.run_list = LIST_HEAD_INIT(tsk.run_list), \
.ioprio = 0, \
.time_slice = HZ, \
.tasks = LIST_HEAD_INIT(tsk.tasks), \
.ptrace_children= LIST_HEAD_INIT(tsk.ptrace_children), \
.ptrace_list = LIST_HEAD_INIT(tsk.ptrace_list), \
.real_parent = &tsk, \
.parent = &tsk, \
.children = LIST_HEAD_INIT(tsk.children), \
.sibling = LIST_HEAD_INIT(tsk.sibling), \
.group_leader = &tsk, \
.group_info = &init_groups, \
.cap_effective = CAP_INIT_EFF_SET, \
.cap_inheritable = CAP_INIT_INH_SET, \
.cap_permitted = CAP_FULL_SET, \
.keep_capabilities = 0, \
.user = INIT_USER, \
.comm = "swapper", \
.thread = INIT_THREAD, \
.fs = &init_fs, \
.files = &init_files, \
.signal = &init_signals, \
.sighand = &init_sighand, \
.pending = { \
.list = LIST_HEAD_INIT(tsk.pending.list), \
.signal = {{0}}}, \
.blocked = {{0}}, \
.alloc_lock = SPIN_LOCK_UNLOCKED, \
.proc_lock = SPIN_LOCK_UNLOCKED, \
.journal_info = NULL, \
.cpu_timers = INIT_CPU_TIMERS(tsk.cpu_timers), \
.fs_excl = ATOMIC_INIT(0), \
}
#define INIT_CPU_TIMERS(cpu_timers) \
{ \
LIST_HEAD_INIT(cpu_timers[0]), \
LIST_HEAD_INIT(cpu_timers[1]), \
LIST_HEAD_INIT(cpu_timers[2]), \
}
#endif