Eric Dumazet 753e9c5cd9 Optimize timespec_trunc() ... The first thing done by timespec_trunc() is : if (gran <= jiffies_to_usecs(1) * 1000) This should really be a test against a constant known at compile time. Alas, it isnt. jiffies_to_usec() was unilined so C compiler emits a function call and a multiply to compute : a CONSTANT. mov $0x1,%edi mov %rbx,0xffffffffffffffe8(%rbp) mov %r12,0xfffffffffffffff0(%rbp) mov %edx,%ebx mov %rsi,0xffffffffffffffc8(%rbp) mov %rsi,%r12 callq ffffffff80232010 <jiffies_to_usecs> imul $0x3e8,%eax,%eax cmp %ebx,%eax This patch reorders kernel/time.c a bit so that jiffies_to_usecs() is defined before timespec_trunc() so that compiler now generates : cmp $0x3d0900,%edx (HZ=250 on my machine) This gives a better code (timespec_trunc() becoming a leaf function), and shorter kernel size as well. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2007-05-08 11:15:01 -07:00
..
irq	MSI: arch must connect the irq and the msi_desc	2007-05-02 19:02:38 -07:00
power	freezer: task->exit_state should be treated as bolean	2007-05-08 11:14:58 -07:00
time	[PATCH] fix jiffies clocksource inittime	2007-04-04 21:12:47 -07:00
.gitignore	gitignore: ignore more generated files	2006-01-03 11:35:26 +01:00
Kconfig.hz	[PATCH] HZ: 300Hz support	2006-12-07 08:39:36 -08:00
Kconfig.preempt	[PATCH] sched: voluntary kernel preemption	2005-06-25 16:24:45 -07:00
Makefile	[PATCH] sysctl: move utsname sysctls to their own file	2007-02-14 08:09:58 -08:00
acct.c	[PATCH] kernel: change uses of f_{dentry, vfsmnt} to use f_path	2006-12-08 08:28:42 -08:00
audit.c	[NETLINK]: Switch cb_lock spinlock to mutex and allow to override it	2007-04-25 22:29:03 -07:00
audit.h	[PATCH] audit: AUDIT_PERM support	2006-09-11 13:32:30 -04:00
auditfilter.c	[PATCH] minor update to rule add/delete messages (ver 2)	2007-02-17 21:30:09 -05:00
auditsc.c	[PATCH] fix deadlock in audit_log_task_context()	2007-03-14 15:27:48 -07:00
capability.c	[PATCH] pid: replace do/while_each_task_pid with do/while_each_pid_task	2007-02-12 09:48:32 -08:00
compat.c	[PATCH] Common compat_sys_sysinfo	2007-02-11 10:51:32 -08:00
configs.c	[PATCH] struct seq_operations and struct file_operations constification	2006-12-07 08:39:46 -08:00
cpu.c	[PATCH] Fix microcode-related suspend problem	2007-04-02 10:06:09 -07:00
cpuset.c	cpusets: allow TIF_MEMDIE threads to allocate anywhere	2007-05-07 12:12:53 -07:00
delayacct.c	KMEM_CACHE(): simplify slab cache creation	2007-05-07 12:12:55 -07:00
dma.c	[PATCH] struct seq_operations and struct file_operations constification	2006-12-07 08:39:46 -08:00
exec_domain.c	Remove obsolete #include <linux/config.h>	2006-06-30 19:25:36 +02:00
exit.c	Return EPERM not ECHILD on security_task_wait failure	2007-05-07 12:12:57 -07:00
extable.c	[PATCH] symbol_put_addr() locks kernel	2006-05-15 11:20:55 -07:00
fork.c	Merge sys_clone()/sys_unshare() nsproxy and namespace handling	2007-05-08 11:15:00 -07:00
futex.c	[PATCH] futex: PI state locking fix	2007-03-16 19:25:06 -07:00
futex_compat.c	[PATCH] __user annotations: futex	2006-10-10 15:37:22 -07:00
hrtimer.c	[NET]: Fix networking compilation errors	2007-04-27 15:31:24 -07:00
itimer.c	[PATCH] hrtimers: prevent possible itimer DoS	2007-02-16 08:13:59 -08:00
kallsyms.c	Extend print_symbol capability	2007-04-30 16:40:39 -07:00
kexec.c	Merge branch 'release' of master.kernel.org:/pub/scm/linux/kernel/git/aegl/linux-2.6	2006-12-07 15:39:22 -08:00
kfifo.c	[PATCH] Numerous fixes to kernel-doc info in source files.	2007-02-11 10:51:32 -08:00
kmod.c	Revert "Driver core: let request_module() send a /sys/modules/kmod/-uevent"	2007-02-23 14:54:57 -08:00
kprobes.c	[PATCH] kprobes: list all active probes in the system	2007-02-20 17:10:14 -08:00
ksysfs.c	remove "struct subsystem" as it is no longer needed	2007-05-02 18:57:59 -07:00
kthread.c	[PATCH] Numerous fixes to kernel-doc info in source files.	2007-02-11 10:51:32 -08:00
latency.c	[PATCH] severing module.h->sched.h	2006-12-04 02:00:22 -05:00
lockdep.c	simplify the stacktrace code	2007-05-08 11:14:58 -07:00
lockdep_internals.h	[PATCH] lockdep: more chains	2006-12-07 08:39:43 -08:00
lockdep_proc.c	[PATCH] remove many unneeded #includes of sched.h	2007-02-14 08:09:54 -08:00
module.c	module: use krealloc	2007-05-08 11:15:00 -07:00
mutex-debug.c	[PATCH] remove many unneeded #includes of sched.h	2007-02-14 08:09:54 -08:00
mutex-debug.h	[PATCH] lockdep: better lock debugging	2006-07-03 15:27:01 -07:00
mutex.c	[PATCH] lockdep: avoid lockdep warning in md	2006-12-08 08:28:39 -08:00
mutex.h	[PATCH] lockdep: prove mutex locking correctness	2006-07-03 15:27:04 -07:00
nsproxy.c	Merge sys_clone()/sys_unshare() nsproxy and namespace handling	2007-05-08 11:15:00 -07:00
panic.c	[PATCH] Add TAINT_USER and ability to set taint flags from userspace	2007-02-11 10:51:29 -08:00
params.c	remove "struct subsystem" as it is no longer needed	2007-05-02 18:57:59 -07:00
pid.c	Merge sys_clone()/sys_unshare() nsproxy and namespace handling	2007-05-08 11:15:00 -07:00
posix-cpu-timers.c	[PATCH] posix timers: RCU optimization for clock_gettime()	2007-02-16 08:14:00 -08:00
posix-timers.c	[PATCH] hrtimers: add high resolution timer support	2007-02-16 08:13:59 -08:00
printk.c	kernel/printk.c: comment fix	2007-02-17 20:10:16 +01:00
profile.c	[PATCH] proc: remove useless (and buggy) ->nlink settings	2007-02-11 10:51:32 -08:00
ptrace.c	[PATCH] pidspace: is_init()	2006-09-29 09:18:12 -07:00
rcupdate.c	[PATCH] rcu: add a prefetch() in rcu_do_batch()	2006-12-07 08:39:40 -08:00
rcutorture.c	rcutorture: Mark rcu_torture_init as __init	2007-05-08 11:15:00 -07:00
relay.c	[PATCH] kernel-doc fixes for 2.6.20-git15 (non-drivers)	2007-03-01 14:53:37 -08:00
resource.c	libata/IDE: remove combined mode quirk	2007-04-28 14:15:59 -04:00
rtmutex-debug.c	Remove all inclusions of <linux/config.h>	2006-10-04 03:38:54 -04:00
rtmutex-debug.h	[PATCH] lockdep: better lock debugging	2006-07-03 15:27:01 -07:00
rtmutex-tester.c	[PATCH] Add include/linux/freezer.h and move definitions from sched.h	2006-12-07 08:39:27 -08:00
rtmutex.c	[PATCH] hrtimers: namespace and enum cleanup	2007-02-16 08:13:58 -08:00
rtmutex.h	[PATCH] lockdep: better lock debugging	2006-07-03 15:27:01 -07:00
rtmutex_common.h	[PATCH] pi-futex: futex_lock_pi/futex_unlock_pi support	2006-06-27 17:32:47 -07:00
rwsem.c	[PATCH] lockdep: prove rwsem locking correctness	2006-07-03 15:27:04 -07:00
sched.c	Safer nr_node_ids and nr_node_ids determination and initial values	2007-05-07 12:12:51 -07:00
seccomp.c	Linux-2.6.12-rc2	2005-04-16 15:20:36 -07:00
signal.c	KMEM_CACHE(): simplify slab cache creation	2007-05-07 12:12:55 -07:00
softirq.c	[PATCH] tick-management: dyntick / highres functionality	2007-02-16 08:13:59 -08:00
softlockup.c	softlockup: s/99/MAX_RT_PRIO/	2007-05-08 11:14:59 -07:00
spinlock.c	[PATCH] lockdep: spin_lock_irqsave_nested()	2006-11-25 13:28:34 -08:00
srcu.c	[PATCH] SRCU: report out-of-memory errors	2006-10-04 07:55:30 -07:00
stacktrace.c	[PATCH] lockdep: stacktrace subsystem, core	2006-07-03 15:27:02 -07:00
stop_machine.c	Use stop_machine_run in the Intel RNG driver	2007-05-08 11:15:00 -07:00
sys.c	remove software_suspend()	2007-05-07 12:12:59 -07:00
sys_ni.c	[PATCH] Create compat_sys_migrate_pages	2006-11-03 12:27:59 -08:00
sysctl.c	Allow reading tainted flag as user	2007-04-24 08:23:08 -07:00
taskstats.c	KMEM_CACHE(): simplify slab cache creation	2007-05-07 12:12:55 -07:00
time.c	Optimize timespec_trunc()	2007-05-08 11:15:01 -07:00
timer.c	[AF_RXRPC]: Make it possible to merely try to cancel timers from a module	2007-04-26 15:46:56 -07:00
tsacct.c	[PATCH] time: x86_64: split x86_64/kernel/time.c up	2007-02-16 08:14:00 -08:00
uid16.c	[PATCH] Add more prevent_tail_call()	2006-04-19 16:27:18 -07:00
user.c	[PATCH] slab: remove kmem_cache_t	2006-12-07 08:39:25 -08:00
utsname.c	Merge sys_clone()/sys_unshare() nsproxy and namespace handling	2007-05-08 11:15:00 -07:00
utsname_sysctl.c	[PATCH] sysctl: remove insert_at_head from register_sysctl	2007-02-14 08:09:59 -08:00
wait.c	[PATCH] uninline init_waitqueue_head()	2006-07-10 13:24:25 -07:00
workqueue.c	[PATCH] Add debugging feature /proc/timer_stat	2007-02-16 08:13:59 -08:00