linux-stable.git/arch/um/include/shared, branch v5.3 Linux kernel stable tree um: fix time travel mode 2019-08-22T22:39:53+00:00 Johannes Berg johannes.berg@intel.com 2019-07-22T07:12:56+00:00 e0917f879536cbf57367429d084775d8224c986c Unfortunately, my build fix for when time travel mode isn't enabled broke time travel mode, because I forgot that we need to use the timer time after the timer has been marked disabled, and thus need to leave the time stored instead of zeroing it. Fix that by splitting the inline into two, so we can call only the _mode() one in the relevant code path. Fixes: b482e48d29f1 ("um: fix build without CONFIG_UML_TIME_TRAVEL_SUPPORT") Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Richard Weinberger <richard@nod.at> 
Unfortunately, my build fix for when time travel mode isn't
enabled broke time travel mode, because I forgot that we need
to use the timer time after the timer has been marked disabled,
and thus need to leave the time stored instead of zeroing it.

Fix that by splitting the inline into two, so we can call only
the _mode() one in the relevant code path.

Fixes: b482e48d29f1 ("um: fix build without CONFIG_UML_TIME_TRAVEL_SUPPORT")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
um: fix build without CONFIG_UML_TIME_TRAVEL_SUPPORT 2019-07-04T07:52:18+00:00 Johannes Berg johannes.berg@intel.com 2019-07-03T08:52:01+00:00 b482e48d29f1461fd0d059a17f32bcfa274127b3 When CONFIG_UML_TIME_TRAVEL_SUPPORT isn't set, the build was broken. Fix this. Fixes: 065038706f77 ("um: Support time travel mode") Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Richard Weinberger <richard@nod.at> 
When CONFIG_UML_TIME_TRAVEL_SUPPORT isn't set, the build was broken.
Fix this.

Fixes: 065038706f77 ("um: Support time travel mode")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
um: Support time travel mode 2019-07-02T21:27:36+00:00 Johannes Berg johannes.berg@intel.com 2019-05-27T08:34:27+00:00 065038706f77a56754e8f0c2556dab7e22dfe577 Sometimes it can be useful to run with "time travel" inside the UML instance, for example for testing. For example, some tests for the wireless subsystem and userspace are based on hwsim, a virtual wireless adapter. Some tests can take a long time to run because they e.g. wait for 120 seconds to elapse for some regulatory checks. This obviously goes faster if it need not actually wait that long, but time inside the test environment just "bumps up" when there's nothing to do. Add CONFIG_UML_TIME_TRAVEL_SUPPORT to enable code to support such modes at runtime, selected on the command line: * just "time-travel", in which time inside the UML instance can move faster than real time, if there's nothing to do * "time-travel=inf-cpu" in which time also moves slower and any CPU processing takes no time at all, which allows to implement consistent behaviour regardless of host CPU load (or speed) or debug overhead. An additional "time-travel-start=<seconds>" parameter is also supported in this case to start the wall clock at this time (in unix epoch). With this enabled, the test mentioned above goes from a runtime of about 140 seconds (with startup overhead and all) to being CPU bound and finishing in 15 seconds (on my slow laptop). Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Richard Weinberger <richard@nod.at> 
Sometimes it can be useful to run with "time travel" inside the
UML instance, for example for testing. For example, some tests
for the wireless subsystem and userspace are based on hwsim, a
virtual wireless adapter. Some tests can take a long time to
run because they e.g. wait for 120 seconds to elapse for some
regulatory checks. This obviously goes faster if it need not
actually wait that long, but time inside the test environment
just "bumps up" when there's nothing to do.

Add CONFIG_UML_TIME_TRAVEL_SUPPORT to enable code to support
such modes at runtime, selected on the command line:
 * just "time-travel", in which time inside the UML instance
   can move faster than real time, if there's nothing to do
 * "time-travel=inf-cpu" in which time also moves slower and
   any CPU processing takes no time at all, which allows to
   implement consistent behaviour regardless of host CPU load
   (or speed) or debug overhead.

An additional "time-travel-start=<seconds>" parameter is also
supported in this case to start the wall clock at this time
(in unix epoch).

With this enabled, the test mentioned above goes from a runtime
of about 140 seconds (with startup overhead and all) to being
CPU bound and finishing in 15 seconds (on my slow laptop).

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
um: Pass nsecs to os timer functions 2019-07-02T21:27:29+00:00 Johannes Berg johannes.berg@intel.com 2019-05-27T08:34:26+00:00 c7c6f3b95303c7de5d52af56c902fcb5abe827df This makes the code clearer and lets the time travel patch have the actual time used for these functions in just one place. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Richard Weinberger <richard@nod.at> 
This makes the code clearer and lets the time travel patch have
the actual time used for these functions in just one place.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
um: Timer code cleanup 2019-07-02T21:27:00+00:00 Johannes Berg johannes.berg@intel.com 2019-05-06T12:39:38+00:00 56fc187065451ebca74edb30d50de5f10a88339b There are some unused functions, and some others that have unused arguments; clean up the timer code a bit. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Richard Weinberger <richard@nod.at> 
There are some unused functions, and some others that have
unused arguments; clean up the timer code a bit.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
um: fix os_timer_one_shot() 2019-07-02T21:26:57+00:00 Johannes Berg johannes.berg@intel.com 2019-05-06T12:39:37+00:00 fcd242c6c835dff4b5334b4db870f9fc23a8e7b7 os_timer_one_shot() gets passed a value "unsigned long delta", so must not have an "int ticks" as that actually ends up being -1, and thus triggering a timer over and over again. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Richard Weinberger <richard@nod.at> 
os_timer_one_shot() gets passed a value "unsigned long delta",
so must not have an "int ticks" as that actually ends up being
-1, and thus triggering a timer over and over again.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
um: Remove obsolete reenable_XX calls 2018-12-27T21:48:35+00:00 Anton Ivanov anton.ivanov@cambridgegreys.com 2018-11-13T15:08:02+00:00 940b241d9050fc354f68c182e99fc3da1ff36bc0 reenable_fd has been a NOP since the introduction of the EPOLL based interrupt controller. reenable_channel() is no longer needed as the flow control is now handled via the write IRQs on the channel. Signed-off-by: Anton Ivanov <anton.ivanov@cambridgegreys.com> Signed-off-by: Richard Weinberger <richard@nod.at> 
reenable_fd has been a NOP since the introduction of the EPOLL
based interrupt controller.
reenable_channel() is no longer needed as the flow control is
now handled via the write IRQs on the channel.

Signed-off-by: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
um: Add support for DISCARD in the UBD Driver 2018-12-27T21:48:20+00:00 Anton Ivanov anton.ivanov@cambridgegreys.com 2018-11-14T18:41:09+00:00 50109b5a03b4024eb6b8df3ab8f427625f54fe92 Support for DISCARD and WRITE_ZEROES in the ubd driver using fallocate. DISCARD is enabled by default and can be disabled using a new UBD command line flag. If the underlying fs on which the UBD image is stored does not support DISCARD the support for both DISCARD and WRITE_ZEROES is turned off. Signed-off-by: Anton Ivanov <anton.ivanov@cambridgegreys.com> Signed-off-by: Richard Weinberger <richard@nod.at> 
Support for DISCARD and WRITE_ZEROES in the ubd driver using
fallocate.

DISCARD is enabled by default and can be disabled using a new
UBD command line flag.

If the underlying fs on which the UBD image is stored does not
support DISCARD the support for both DISCARD and WRITE_ZEROES
is turned off.

Signed-off-by: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
um: remove unused AIO code 2018-10-29T21:23:12+00:00 Christoph Hellwig hch@lst.de 2018-07-11T07:32:39+00:00 369cca266860db8222c991fced8caa42c3e5b05f Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Richard Weinberger <richard@nod.at> 
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Richard Weinberger <richard@nod.at>
um: remove uml initcalls 2018-06-10T20:49:14+00:00 Alexander Pateenok pateenoc@gmail.com 2018-04-23T18:20:17+00:00 cca76c1ad61d08097af5a691195f9a42d72e978f __uml_initcall() is not used and .uml.initcall.init section is empty: $ grep -r '__uml_initcall(' arch/um/include/shared/init.h:#define __uml_initcall(fn) \ $ readelf -s ../umobj/linux | grep __uml_initcall 23214: 00000000603b75d8 0 NOTYPE GLOBAL DEFAULT 32 __uml_initcall_start 25337: 00000000603b75d8 0 NOTYPE GLOBAL DEFAULT 32 __uml_initcall_end So it is unnecessary. Signed-off-by: Alexander Pateenok <pateenoc@gmail.com> Signed-off-by: Richard Weinberger <richard@nod.at> 
__uml_initcall() is not used and .uml.initcall.init section is empty:

$ grep -r '__uml_initcall('
arch/um/include/shared/init.h:#define __uml_initcall(fn)	\
$ readelf -s ../umobj/linux | grep __uml_initcall
 23214: 00000000603b75d8     0 NOTYPE  GLOBAL DEFAULT   32 __uml_initcall_start
 25337: 00000000603b75d8     0 NOTYPE  GLOBAL DEFAULT   32 __uml_initcall_end

So it is unnecessary.

Signed-off-by: Alexander Pateenok <pateenoc@gmail.com>
Signed-off-by: Richard Weinberger <richard@nod.at>