kernel_optimize_test/arch/um
Steven Rostedt 69be8f1896 [PATCH] convert signal handling of NODEFER to act like other Unix boxes.
It has been reported that the way Linux handles NODEFER for signals is
not consistent with the way other Unix boxes handle it.  I've written a
program to test the behavior of how this flag affects signals and had
several reports from people who ran this on various Unix boxes,
confirming that Linux seems to be unique on the way this is handled.

The way NODEFER affects signals on other Unix boxes is as follows:

1) If NODEFER is set, other signals in sa_mask are still blocked.

2) If NODEFER is set and the signal is in sa_mask, then the signal is
still blocked. (Note: this is the behavior of all tested but Linux _and_
NetBSD 2.0 *).

The way NODEFER affects signals on Linux:

1) If NODEFER is set, other signals are _not_ blocked regardless of
sa_mask (Even NetBSD doesn't do this).

2) If NODEFER is set and the signal is in sa_mask, then the signal being
handled is not blocked.

The patch converts signal handling in all current Linux architectures to
the way most Unix boxes work.

Unix boxes that were tested:  DU4, AIX 5.2, Irix 6.5, NetBSD 2.0, SFU
3.5 on WinXP, AIX 5.3, Mac OSX, and of course Linux 2.6.13-rcX.

* NetBSD was the only other Unix to behave like Linux on point #2. The
main concern was brought up by point #1 which even NetBSD isn't like
Linux.  So with this patch, we leave NetBSD as the lonely one that
behaves differently here with #2.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-29 10:03:11 -07:00
..
drivers
include
kernel
os-Linux
scripts
sys-i386
sys-ia64
sys-ppc
sys-x86_64
util
config.release
defconfig
Kconfig
Kconfig_char
Kconfig_i386
Kconfig_net
Kconfig_scsi
Kconfig_x86_64
Kconfig.debug
Makefile
Makefile-i386
Makefile-ia64
Makefile-os-Linux
Makefile-ppc
Makefile-skas
Makefile-tt
Makefile-x86_64