Commit Graph
330 Commits
Author SHA1 Message Date
Christian Lindig f99941871a tools/ocaml: cleanup to reduce compiler warnings
This commit cleans up code to reduce compiler warnings:

* remove unused open statements (warning 33)
* remove unused 'rec' declarations (warnign 39)
* remove unused type declarations (warning 34)
* mark unused variables with an underscore (warning 27)
* mark unused value declarations with an underscore (warning 32)

This commit does not include changes to fix compiler warnings 52
(matching against strings in exceptions). These changes have no impact
on functionality.

Signed-off-by: Christian Lindig <christian.lindig@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
2018-11-14 18:22:09 +00:00
Christian Lindig 87e89bd112 tools/ocaml: make type of Xsraw.sync more precise
The type of Xsraw.sync is made more precise:

from val sync : (Xenbus.Xb.t -> 'a) -> con -> string
to   val sync : (Xenbus.Xb.t -> unit) -> con -> string

The first argument is enforced to return unit rather than a value that
is not used anyway.

[ No functional change. -iwj ]

Signed-off-by: Christian Lindig <christian.lindig@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
2018-11-01 11:24:03 +00:00
Christian Lindig 6230dde2ed tools/ocaml: Re-introduce Xenctrl.with_intf wrapper
Commit 81946a73dc removed
Xenctrl.with_intf based on its undesirable behaviour of opening and
closing a Xenctrl connection with every invocation. This commit
re-introduces with_intf but with an updated behaviour: it maintains a
global Xenctrl connection which is opened upon first usage and kept
open. This handle can be obtained by clients using new functions
get_handle() and close_handle().

The main motivation of re-introducing with_intf is that otherwise
clients will have to implement this functionality individually.

Signed-off-by: Christian Lindig <christian.lindig@citrix.com>
Reviewed-by: Ian Jackson <ian.jackson@eu.citrix.com>
2018-11-01 11:22:54 +00:00
Yang Qian 7b20a865bc tools/ocaml: Release the global lock before invoking block syscalls
Functions related with event channel are parallelizable, so release global
lock before invoking C function which will finally call block syscalls.

Signed-off-by: Yang Qian <yang.qian@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2018-10-08 10:58:55 +01:00
Andrew Cooper 81946a73dc tools/ocaml: Delete the Xenctrl.with_intf wrapper
This wrapper hides an opening and closing of the xenctrl handle, which amongst
other things opens and closes multiple device files.

A process should create one handle at the start of day and reuse that; indeed
there is no guarentee that the process will retain sufficient permissions to
re-open /dev/xen/privcmd at a later point.

With the final user of Xenctrl.with_intf removed, drop the wrapper entirely.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
2018-10-04 14:54:36 +01:00
Andrew Cooper 129025fe30 oxenstored: Don't re-open a xenctrl handle for every domain introduction
Currently, an xc handle is opened in main() which is used for cleanup
activities, and a new xc handle is temporarily opened every time a domain is
introduced.  This is inefficient, and amongst other things, requires full root
privileges for the lifetime of oxenstored.

All code using the Xenctrl handle is in domains.ml, so initialise xc as a
global (now happens just before main() is called) and drop it as a parameter
from Domains.create and Domains.cleanup.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
2018-10-04 14:54:36 +01:00
Andrew Cooper df8601938a tools/ocaml: Strip all trailing whitespace
No functional change.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
2018-10-04 14:54:36 +01:00
Yang Qian 89faccfd35 tools/ocaml: Add OCaml binding of virq bind
1. Add a common bind virq function
2. Reduce the stub code of `bind_dom_exc_virq`

Signed-off-by: Yang Qian <yang.qian@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
2018-09-27 11:19:48 +01:00
Andrew Cooper 4737fa52ce tools: Pass max_vcpus to XEN_DOMCTL_createdomain
XEN_DOMCTL_max_vcpus is a mandatory hypercall, but nothing actually prevents a
toolstack from unpausing a domain with no vcpus.

Originally, d->vcpus[] was an embedded array in struct domain, but c/s
fb442e217 "x86_64: allow more vCPU-s per guest" in Xen 4.0 altered it to being
dynamically allocated.  A side effect of this is that d->vcpu[] is NULL until
XEN_DOMCTL_max_vcpus has completed, but a lot of hypercalls blindly
dereference it.

Even today, the behaviour of XEN_DOMCTL_max_vcpus is a mandatory singleton
call which can't change the number of vcpus once a value has been chosen.

In preparation to remote the hypercall, extend xen_domctl_createdomain with
the a max_vcpus field and arrange for all callers to pass the appropriate
value.  There is no change in construction behaviour yet, but later patches
will rearrange the hypervisor internals.

For the python stubs, extend the domain_create keyword list to take a
max_vcpus parameter, in lieu of deleting the pyxc_domain_max_vcpus function.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
2018-08-31 12:06:53 +01:00
Andrew Cooper a903bf5233 tools: Pass grant table limits to XEN_DOMCTL_set_gnttab_limits
XEN_DOMCTL_set_gnttab_limits is a fairly new hypercall, and is strictly
mandatory.  As it pertains to domain limits, it should be provided at
createdomain time.

In preparation to remove the hypercall, extend xen_domctl_createdomain with
the fields and arrange for all callers to pass appropriate details.  There is
no change in construction behaviour yet, but later patches will rearrange the
hypervisor internals, then delete the hypercall.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
2018-08-31 12:06:53 +01:00
Andrew Cooper 4a83497635 xen/domctl: Merge set_max_evtchn into createdomain
set_max_evtchn is somewhat weird.  It was introduced with the event_fifo work,
but has never been used.  Still, it is a bounding on resources consumed by the
event channel infrastructure, and should be part of createdomain, rather than
editable after the fact.

Drop XEN_DOMCTL_set_max_evtchn completely (including XSM hooks and libxc
wrappers), and retain the functionality in XEN_DOMCTL_createdomain.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
2018-08-15 19:40:28 +01:00
Andrew Cooper 54ed251dc7 tools: Rework xc_domain_create() to take a full xen_domctl_createdomain
In future patches, the structure will be extended with further information,
and this is far cleaner than adding extra parameters.

The python stubs are the only user which passes NULL for the existing config
option (which is actually the arch substructure).  Therefore, the #ifdefary
moves to compensate.

For libxl, pass the full config object down into
libxl__arch_domain_{prepare,save}_config(), as there are in practice arch
specific settings in the common part of the structure (flags s3_integrity and
oos_off specifically).

No practical change in behaviour.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
2018-08-15 19:40:28 +01:00
Andrew Cooper acc2a06c78 tools/ocaml: Pass a full domctl_create_config into stub_xc_domain_create()
The underlying C function is about to make the same change, and the structure
is going to gain extra fields.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
2018-08-15 19:40:28 +01:00
Christian Lindig 73392c7fd1 tools/oxenstored: Make evaluation order explicit
In Store.path_write(), Path.apply_modify() updates the node_created
reference and both the value of apply_modify() and node_created are
returned by path_write().

At least with OCaml 4.06.1 this leads to the value of node_created being
returned *before* it is updated by apply_modify().  This in turn leads
to the quota for a domain not being updated in Store.write().  Hence, a
guest can create an unlimited number of entries in xenstore.

The fix is to make evaluation order explicit.

This is XSA-272.

Signed-off-by: Christian Lindig <christian.lindig@citrix.com>
Reviewed-by: Rob Hoes <rob.hoes@citrix.com>
2018-08-14 16:56:46 +01:00
Wei Liu 6e2a53afa1 ocaml: remove undefined behaviour in systemd_stubs.c
Clang complains:

systemd_stubs.c:51:8: error: shifting a negative signed value is undefined [-Werror,-Wshift-negative-value]
        ret = Val_int(-1U);
              ^~~~~~~~~~~~

Since sd_notify_fd has a signature of unit -> unit, we simply change
the return value to Val_unit.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2018-07-24 09:16:16 +01:00
Andrew Cooper 36d94c17fa tools/ocaml: Drop int_array_of_uuid_string()
This function is entirely internal to xenctrl stubs, and serves only to
convert the uuid string to an integer array (making 16 memory allocations as
it goes), while the C stubs turns the integer array back into a binary array.

Instead, pass the string all the way down into C, and have sscanf() unpack it
directly into a xen_domain_handle_t object.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
2018-07-04 16:25:01 +01:00
Andrew Cooper cf4fa365c7 tools/ocaml: Drop domain_create_flag_table[]
This is a logarithm in disguise.  Update the logic to match how
x86_arch_emulation_flags works in c/s 9d683b5e37 and b38d96f596.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
2018-07-04 16:25:01 +01:00
Marcello Seri 3960f3a523 ocaml/xenstored: reduce use of unsafe conversions
The rationalisation of the Xs_ring interface in the xb library
allows to further reduce the unsafe calls withouth introducing
copies. This patch also contains some further code cleanups.

Signed-off-by: Marcello Seri <marcello.seri@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
Tested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
2018-06-04 11:17:22 +01:00
Marcello Seri ec7d54dd1a ocaml/libs/xb: Use bytes in place of strings for mutable buffers
Since Ocaml 4.06.0, that made safe-string on by default, the compiler is
allowed to perform optimisations on immutable strings.  They should no
longer be used as mutable buffers, and bytes should be used instead.

The C stubs for Xs_ring have been updated to use bytes, and the interface
rationalised mimicking the new Unix module in the standard library (the
implementation of Unix.write_substring uses unsafe_of_string in the exact same
way, and both the write implementations are using the bytes as an immutable
payload for the write).

Signed-off-by: Marcello Seri <marcello.seri@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
Tested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
2018-06-04 11:17:22 +01:00
John Thomson 2adc90908f tools/ocaml/libs/xc fix gcc-8 format-truncation warning
CC       xenctrl_stubs.o
xenctrl_stubs.c: In function 'failwith_xc':
xenctrl_stubs.c:65:17: error: 'snprintf' output may be truncated before the last format character [-Werror=format-truncation=]
      "%d: %s: %s", error->code,
                 ^
xenctrl_stubs.c:64:4: note: 'snprintf' output 6 or more bytes (assuming 1029) into a destination of size 1028
    snprintf(error_str, sizeof(error_str),
    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      "%d: %s: %s", error->code,
      ~~~~~~~~~~~~~~~~~~~~~~~~~~
      xc_error_code_to_desc(error->code),
      ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      error->message);
      ~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
make[8]: *** [/build/xen-git/src/xen/tools/ocaml/libs/xc/../../Makefile.rules:37: xenctrl_stubs.o] Error 1
m

Signed-off-by: John Thomson <git@johnthomson.fastmail.com.au>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
2018-05-16 09:19:21 +01:00
Marcello Seri 2d6a8daef8 tools: reduce copies b/w ocaml Strings and Bytes
When xenstore was ported to the new safe-string interface, it mostly
happened by making copyies of string into bytes and back.  The ideal
fix would be to rewrite all of the relevant interfaces to be uniformly
using bytes, but in the meanwhile we can improve the code by using unsafe
conversion functions (see
 https://caml.inria.fr/pub/docs/manual-ocaml/libref/Bytes.html#3_Unsafeconversionsforadvancedusers).

In most cases we own the bytes that we are converting to string, or we
immediately make copies that we then mutate, or we use them immutably
as payloads for writes. In all these cases it is safe to use the unsafe
functions and prevent a copy.

This patch updates the code to use the unsafe conversions where possible.

Signed-off-by: Marcello Seri <marcello.seri@citrix.com>
Reviewed-by: Christian Lindig <christian.lindig@citrix.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
2018-04-06 09:29:21 +01:00
Michael Young 9f3b40e8fe make xen ocaml safe-strings compliant
Xen built with ocaml 4.06 gives errors such as
Error: This expression has type bytes but an expression was
        expected of type string
as Byte and safe-strings which were introduced in 4.02 are the
default in 4.06.
This patch which is partly by Richard W.M. Jones of Red Hat
from https://bugzilla.redhat.com/show_bug.cgi?id=1526703
fixes these issues.

Signed-off-by: Michael Young <m.a.young@durham.ac.uk>
Reviewed-by: Christian Lindig<christian.lindig@citrix.com>
2018-03-13 15:54:23 +00:00
Wei Liu 3a6719f40f Revert "make xen ocaml safe-strings compliant"
This reverts commit df1e4c6e7f.

Oxenstored is broken by this change.
2018-02-12 11:05:35 +00:00
Wei Liu f2728cfb4c Revert "ocaml/libs/xb: update xb.mli in accordance with df1e4c6e7f8"
This reverts commit a53b9b987a.
2018-02-12 11:05:35 +00:00
Wei Liu c93014ad3a ocaml/libs/xb: don't generate *.mli automatically
To stay in line with other parts of the ocaml code base.

This requires committing a bunch of mli files in tree.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
2018-02-07 17:31:13 +00:00
Wei Liu a53b9b987a ocaml/libs/xb: update xb.mli in accordance with df1e4c6e7f
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
2018-02-07 17:30:37 +00:00
Michael Young df1e4c6e7f make xen ocaml safe-strings compliant
Xen built with ocaml 4.06 gives errors such as
Error: This expression has type bytes but an expression was
        expected of type string
as Byte and safe-strings which were introduced in 4.02 are the
default in 4.06.
This patch which is mostly by Richard W.M. Jones of Red Hat
from https://bugzilla.redhat.com/show_bug.cgi?id=1526703
fixes these issues.

v2: drop tools/ocaml/libs/xc/xenctrl.ml from the patch as the
affected code was removed by commit d933f1a53c
tools/ocaml: Drop coredump infrastructure

Signed-off-by: Michael Young <m.a.young@durham.ac.uk>
Reviewed-by: Christian Lindig <christian.lindig@citrix.com>
[ wei: remove trailing whitespaces ]
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
2018-02-07 11:24:43 +00:00
Andrew Cooper 94450e36bf xen: Drop DOMCTL_getmemlist and xc_get_pfn_list()
c/s 4ddf474e2 "tools/xen-mceinj: Pass in GPA when injecting through
MSR_MCI_ADDR" removed the remaining user of hypercall.

It has been listed as broken, deprecated and wont-fix since XSA-74, so take
this opportunity to remove it completely.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
2018-01-26 18:28:47 +00:00
Andrew Cooper d933f1a53c tools/ocaml: Drop coredump infrastructure
It is unused, and uses an obsolete hypercall which has never ever functioned
for HVM guests.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
2018-01-26 18:28:47 +00:00
Wei Liu 81838c9067 ocaml: fix arm build
ARM doesn't have emulation_flags in the arch_domainconfig.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Julien Grall <julien.grall@linaro.org>
2018-01-18 10:54:08 +00:00
Jon Ludlam b38d96f596 tools/ocaml: Extend domain_create() to take arch_domainconfig
No longer passing NULL into xc_domain_create() allows for the creation
of PVH guests.

Signed-off-by: Jon Ludlam <jonathan.ludlam@citrix.com>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
2018-01-16 18:34:04 +00:00
Andrew Cooper 9d683b5e37 tools/ocaml: Expose arch_config in domaininfo
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
2018-01-16 18:34:04 +00:00
Oleksandr Grytsov cac1f06061 libxl: change nic to use generec add function
Signed-off-by: Oleksandr Grytsov <oleksandr_grytsov@epam.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
[ wei: add missing semicolon ]
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
2017-09-13 09:40:46 +01:00
Oleksandr Grytsov fbbaf2cc98 libxl: change disk to use generic getting list functions
Signed-off-by: Oleksandr Grytsov <oleksandr_grytsov@epam.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
2017-09-13 10:54:45 +03:00
Petre Pircalabu f2b40dabab Makefile: Fix uninstall target
Running "make uninstall" does not remove all installed files, a
situation which might cause link related issues if xen is re-installed
in a different location.
In order to make uninstall correctly remove the files it is best
the process should be done recursively by mirroring each "install"
target with an "uninstall" who removes the installed files.

An exception to this rule is uninstalling the files produced by
"qemu-xen-dir-remote" and "qemu-xen-traditional-dir", which are external
to the project. These projects do not implement an "uninstall" target so
the files have to be removed manually.

Signed-off-by: Petre Pircalabu <ppircalabu@bitdefender.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
2017-07-28 17:47:42 +01:00
Andrew Cooper 73771b89fd tools: Drop xc_cpuid_check() and bindings
There are no current users which I can locate.  One piece of xend which didn't
move forwards into xl/libxl is this:

  #   Configure host CPUID consistency checks, which must be satisfied for this
  #   VM to be allowed to run on this host's processor type:
  #cpuid_check=[ '1:ecx=xxxxxxxxxxxxxxxxxxxxxxxxxx1xxxxx' ]
  # - Host must have VMX feature flag set

The implementation of xc_cpuid_check() is conceptually broken.  Dom0's view of
CPUID is not the approprite view to check, and will be wrong in the presence
of CPUID masking/faulting, and for HVM-based toolstack domains.

If it turns out that the functionality is required, it should be implemented
in terms of XEN_SYSCTL_get_cpuid_policy to use the proper CPUID view.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
2017-07-20 17:35:52 +01:00
Thomas Sanders 864a269682 oxenstored: trim history in the frequent_ops function
We were trimming the history of commits only at the end of each
transaction (regardless of how it ended).

Therefore if non-transactional writes were being made but no
transactions were being ended, the history would grow
indefinitely. Now we trim the history at regular intervals.

Signed-off-by: Thomas Sanders <thomas.sanders@citrix.com>
2017-07-04 10:39:42 +01:00
Zhongze Liu 2d78f78a14 tools: fix several "format-truncation" warnings with GCC 7
GCC 7.1.1 complains that several buffers passed to snprintf() in xenpmd
and tools/ocmal/xc are too small to hold the largest possible resulting string,
which is calculated by adding up the maximum length of all the substrings.

The warnings are treated as errors by -Werror, and goes like this (abbreviated):

xenpmd.c:94:36: error: ‘%s’ directive output may be truncated writing up to
255 bytes into a region of size 13 [-Werror=format-truncation=]
     #define BATTERY_INFO_FILE_PATH "/proc/acpi/battery/%s/info"
                                    ^
xenpmd.c:113:13: note: ‘snprintf’ output between 25 and 280 bytes into a
destination of size 32

xenpmd.c:95:37: error: ‘%s’ directive output may be truncated writing up to
255 bytes into a region of size 13 [-Werror=format-truncation=]
     #define BATTERY_STATE_FILE_PATH "/proc/acpi/battery/%s/state"
                                     ^
xenpmd.c:116:13: note: ‘snprintf’ output between 26 and 281 bytes into a
destination of size 32

xenctrl_stubs.c:65:15: error: ‘%s’ directive output may be truncated writing
up to 1023 bytes into a region of size 252 [-Werror=format-truncation=]
      "%d: %s: %s", error->code,
               ^~
xenctrl_stubs.c:64:4: note: ‘snprintf’ output 5 or more bytes (assuming 1028)
into a destination of size 256

Enlarge the size of these buffers as suggested by the complier
(and slightly rounded) to fix the warnings.

No functional changes.

Signed-off-by: Zhongze Liu <blackskygg@gmail.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
2017-06-19 12:34:31 +01:00
Wei Liu 904f8957e4 oxenstored: provide options to define xenstored devices
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Christian Lindig <christian.lindig@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Release-acked-by: Julien Grall <julien.grall@arm.com>
2017-04-20 12:02:55 +01:00
Jonathan Davies ce70926b4f oxenstored: make --restart option best-effort
Only attempt to restore from saved state if it exists.

Without this, oxenstored immediately exits with an exception if the
--restart option is provided but the state file is not present.

(The time-of-check to time-of-use race isn't a concern as oxenstored is
the only thing that should write the state file.)

Signed-off-by: Jonathan Davies <jonathan.davies@citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Christian Lindig <christian.lindig@citrix.com>
Release-acked-by: Julien Grall <julien.grall@arm.com>
2017-04-10 14:46:45 +01:00
Jonathan Davies 3475c97ee4 oxenstored: improve event-channel binding logging
It's useful to see a bit more detail when an inter-domain event-channel
is bound, especially over an oxenstored restart.

Signed-off-by: Jonathan Davies <jonathan.davies@citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Christian Lindig <christian.lindig@citrix.com>
Release-acked-by: Julien Grall <julien.grall@arm.com>
2017-04-10 14:46:28 +01:00
Jonathan Davies 27ce9d49d0 oxenstored: save remote evtchn port, not local port
Previously, Domain.dump output the number of the local port
corresponding to each domain's event-channel. However, when oxenstored
exits, it closes /dev/xen/evtchn which causes the kernel to close the
local port (evtchn_release), so this port is no longer useful.

Instead, store the remote port. This can be used to reconnect the
event-channel by binding the original remote port to a fresh local port.

Indeed, the logic for parsing the stored state already expects a remote
port as it passes the parsed port number to Domain.make (via
Domains.create), which takes a remote port.

Signed-off-by: Jonathan Davies <jonathan.davies@citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Christian Lindig <christian.lindig@citrix.com>
Release-acked-by: Julien Grall <julien.grall@arm.com>
2017-04-10 14:46:25 +01:00
Jonathan Davies 506114e918 oxenstored: avoid leading slash in paths in saved store state
Internally, paths are represented as lists of strings, where
  * path "/" is represented by []
  * path "/local/domain/0" is represented by ["local"; "domain"; "0"]
(see comment for Store.Path.t).

However, the traversal function generated paths like
    [""; "local"; "domain"; "0"]
because the name of the root node is "". Change it to generate paths
correctly.

Furthermore, the function passed to Store.dump_fct would render the node
"foo" under the path [] as "//foo". Change this to return "/foo".

Signed-off-by: Jonathan Davies <jonathan.davies@citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Christian Lindig <christian.lindig@citrix.com>
Release-acked-by: Julien Grall <julien.grall@arm.com>
2017-04-10 14:46:21 +01:00
Jonathan Davies 0c7b704097 oxenstored: initialise logging earlier
Otherwise we miss out on messages from things that try to log earlier in
the start-up procedure.

Signed-off-by: Jonathan Davies <jonathan.davies@citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Christian Lindig <christian.lindig@citrix.com>
Release-acked-by: Julien Grall <julien.grall@arm.com>
2017-04-10 14:46:19 +01:00
Thomas Sanders 6d969f1283 oxenstored transaction conflicts: improve logging
For information related to transaction conflicts, potentially frequent
logging at "info" priority has been changed to "debug" priority, and
once per two minutes there is an "info" priority summary.

Additional detailed logging has been added at "debug" priority.

Signed-off-by: Thomas Sanders <thomas.sanders@citrix.com>
2017-03-28 13:07:04 +01:00
Thomas Sanders 4bcfc6881e oxenstored: don't wake to issue no conflict-credit
In the main loop, when choosing the timeout for the select function
call, we were setting it so as to wake up to issue conflict-credit to
any domains that could accept it. When xenstore is idle, this would
mean waking up every 50ms (by default) to do no work. With this
commit, we check whether any domain is below its cap, and if not then
we set the timeout for longer (the same timeout as before the
conflict-protection feature was added).

Signed-off-by: Thomas Sanders <thomas.sanders@citrix.com>
Reviewed-by: Jonathan Davies <jonathan.davies@citrix.com>
2017-03-28 13:07:04 +01:00
Thomas Sanders b2a4105820 oxenstored: do not commit read-only transactions
The packet telling us to end the transaction has always carried an
argument telling us whether to commit.

If the transaction made no modifications to the tree, now we ignore
that argument and do not commit: it is just a waste of effort.

This makes read-only transactions immune to conflicts, and means that
we do not need to store any of their details in the history that is
used for assigning blame for conflicts.

We count a transaction as a read-only transaction only if it contains
no operations that modified the tree.

This means that (for example) a transaction that creates a new node
then deletes it would NOT count as read-only, even though it makes no
change overall. A more sophisticated algorithm could judge the
transaction based on comparison of its initial and final states, but
this would add complexity and computational cost.

Signed-off-by: Thomas Sanders <thomas.sanders@citrix.com>
Reviewed-by: Jonathan Davies <jonathan.davies@citrix.com>
2017-03-28 13:07:04 +01:00
Thomas Sanders 467c9de412 oxenstored: allow self-conflicts
We already avoid inter-domain conflicts but now allow intra-domain
conflicts.  Although there are no known practical examples of a domain
that might perform operations that conflict with its own transactions,
this is conceivable, so here we avoid changing those semantics
unnecessarily.

When a transaction commit fails with a conflict and we look through
the history of commits to see which connection(s) to blame, ignore
historical commits that were made by the same connection as the
failing commit.

Signed-off-by: Thomas Sanders <thomas.sanders@citrix.com>
Reviewed-by: Jonathan Davies <jonathan.davies@citrix.com>
2017-03-28 13:07:04 +01:00
Jonathan Davies 8ddbce0426 oxenstored: blame the connection that caused a transaction conflict
Blame each connection found to have made a commit that would cause this
transaction to fail. Each blamed connection is penalised by having its
conflict-credit decremented.

Note the change in semantics for the replay function: we no longer stop after
finding the first operation that can't be replayed. This allows us to identify
all operations that conflicted with this transaction, not just the one that
conflicted first.

Signed-off-by: Jonathan Davies <jonathan.davies@citrix.com>
Signed-off-by: Thomas Sanders <thomas.sanders@citrix.com>
v1 Reviewed-by: Christian Lindig <christian.lindig@citrix.com>

Changes since v1:
 * use correct log levels for informational messages
Changes since v2:
 * fix the blame algorithm and improve logging
   (fix was reviewed by Jonathan Davies)

Signed-off-by: Thomas Sanders <thomas.sanders@citrix.com>
2017-03-28 13:07:04 +01:00
Jonathan Davies 57718f2e14 oxenstored: track commit history
Since the list of historic activity cannot grow without bound, it is safe to use
this to track commits.

Signed-off-by: Jonathan Davies <jonathan.davies@citrix.com>
Reviewed-by: Thomas Sanders <thomas.sanders@citrix.com>
2017-03-28 13:07:04 +01:00