Commit 4d672e7a authored Feb 04, 2008 by Davide Libenzi Committed by Linus Torvalds Feb 05, 2008

timerfd: new timerfd API

This is the new timerfd API as it is implemented by the following patch:

int timerfd_create(int clockid, int flags);
int timerfd_settime(int ufd, int flags,
		    const struct itimerspec *utmr,
		    struct itimerspec *otmr);
int timerfd_gettime(int ufd, struct itimerspec *otmr);

The timerfd_create() API creates an un-programmed timerfd fd.  The "clockid"
parameter can be either CLOCK_MONOTONIC or CLOCK_REALTIME.

The timerfd_settime() API give new settings by the timerfd fd, by optionally
retrieving the previous expiration time (in case the "otmr" parameter is not
NULL).

The time value specified in "utmr" is absolute, if the TFD_TIMER_ABSTIME bit
is set in the "flags" parameter.  Otherwise it's a relative time.

The timerfd_gettime() API returns the next expiration time of the timer, or
{0, 0} if the timerfd has not been set yet.

Like the previous timerfd API implementation, read(2) and poll(2) are
supported (with the same interface).  Here's a simple test program I used to
exercise the new timerfd APIs:

http://www.xmailserver.org/timerfd-test2.c



[akpm@linux-foundation.org: coding-style cleanups]
[akpm@linux-foundation.org: fix ia64 build]
[akpm@linux-foundation.org: fix m68k build]
[akpm@linux-foundation.org: fix mips build]
[akpm@linux-foundation.org: fix alpha, arm, blackfin, cris, m68k, s390, sparc and sparc64 builds]
[heiko.carstens@de.ibm.com: fix s390]
[akpm@linux-foundation.org: fix powerpc build]
[akpm@linux-foundation.org: fix sparc64 more]
Signed-off-by: Davide Libenzi <davidel@xmailserver.org>
Cc: Michael Kerrisk <mtk-manpages@gmx.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Davide Libenzi <davidel@xmailserver.org>
Cc: Michael Kerrisk <mtk-manpages@gmx.net>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Davide Libenzi <davidel@xmailserver.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 5e05ad7d

arch/alpha/kernel/systbls.S

+1 −1

Original line number	Diff line number	Diff line
		@@ -495,7 +495,7 @@ sys_call_table:
		.quad sys_epoll_pwait
		.quad sys_utimensat /* 475 */
		.quad sys_signalfd
		.quad sys_timerfd
		.quad sys_ni_syscall
		.quad sys_eventfd

		.size sys_call_table, . - sys_call_table

arch/arm/kernel/calls.S

+1 −1

Original line number	Diff line number	Diff line
		@@ -359,7 +359,7 @@
		CALL(sys_kexec_load)
		CALL(sys_utimensat)
		CALL(sys_signalfd)
		/* 350 */ CALL(sys_timerfd)
		/* 350 */ CALL(sys_ni_syscall)
		CALL(sys_eventfd)
		CALL(sys_fallocate)
		#ifndef syscalls_counted

arch/blackfin/mach-common/entry.S

+1 −1

Original line number	Diff line number	Diff line
		@@ -1373,7 +1373,7 @@ ENTRY(_sys_call_table)
		.long _sys_epoll_pwait
		.long _sys_utimensat
		.long _sys_signalfd
		.long _sys_timerfd
		.long _sys_ni_syscall
		.long _sys_eventfd /* 350 */
		.long _sys_pread64
		.long _sys_pwrite64

arch/cris/arch-v10/kernel/entry.S

+1 −1

Original line number	Diff line number	Diff line
		@@ -1167,7 +1167,7 @@ sys_call_table:
		.long sys_epoll_pwait
		.long sys_utimensat /* 320 */
		.long sys_signalfd
		.long sys_timerfd
		.long sys_ni_syscall
		.long sys_eventfd
		.long sys_fallocate

arch/ia64/kernel/entry.S

+1 −1

Original line number	Diff line number	Diff line
		@@ -1586,7 +1586,7 @@ sys_call_table:
		data8 sys_epoll_pwait // 1305
		data8 sys_utimensat
		data8 sys_signalfd
		data8 sys_timerfd
		data8 sys_ni_syscall
		data8 sys_eventfd

		.org sys_call_table + 8*NR_syscalls // guard against failures to increase NR_syscalls

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