![Eric Dumazet](/assets/img/avatar_default.png)
1) Reduce the size of (struct fdtable) to exactly 64 bytes on 32bits platforms, lowering kmalloc() allocated space by 50%. 2) Reduce the size of (files_struct), using a special 32 bits (or 64bits) embedded_fd_set, instead of a 1024 bits fd_set for the close_on_exec_init and open_fds_init fields. This save some ram (248 bytes per task) as most tasks dont open more than 32 files. D-Cache footprint for such tasks is also reduced to the minimum. 3) Reduce size of allocated fdset. Currently two full pages are allocated, that is 32768 bits on x86 for example, and way too much. The minimum is now L1_CACHE_BYTES. UP and SMP should benefit from this patch, because most tasks will touch only one cache line when open()/close() stdin/stdout/stderr (0/1/2), (next_fd, close_on_exec_init, open_fds_init, fd_array[0 .. 2] being in the same cache line) Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
136 lines
3.6 KiB
C
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 = EMBEDDED_FD_SET_SIZE, \
|
|
.fd = &init_files.fd_array[0], \
|
|
.close_on_exec = (fd_set *)&init_files.close_on_exec_init, \
|
|
.open_fds = (fd_set *)&init_files.open_fds_init, \
|
|
.rcu = RCU_HEAD_INIT, \
|
|
.free_files = NULL, \
|
|
.next = NULL, \
|
|
}
|
|
|
|
#define INIT_FILES \
|
|
{ \
|
|
.count = ATOMIC_INIT(1), \
|
|
.fdt = &init_files.fdtab, \
|
|
.fdtab = INIT_FDTABLE, \
|
|
.file_lock = SPIN_LOCK_UNLOCKED, \
|
|
.next_fd = 0, \
|
|
.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
|