918b8842a8 changed CPSR and SPSR to be stored as 64bit values.
This is fixing the print size in some tools to use 64bit type.
Fixes: 918b8842a8 ("arm64: Change type of hsr, cpsr, spsr_el1 to uint64_t")
Signed-off-by: Bertrand Marquis <bertrand.marquis@arm.com>
Reviewed-by: Michal Orzel <michal.orzel@arm.com>
Tested-by: Michal Orzel <michal.orzel@arm.com>
literal strings are not meant to be modified. So we should use const
char * rather than char * when we want to store a pointer to them.
Signed-off-by: Julien Grall <jgrall@amazon.com>
Acked-by: George Dunlap <george.dunlap@citrix.com>
Use unsigned char variable, or cast to (unsigned char), for
tolower()/islower() and friends. Fix compiler error
array subscript has type 'char' [-Werror=char-subscripts]
Signed-off-by: Manuel Bouyer <bouyer@netbsd.org>
Reviewed-by: Ian Jackson <ian.jackson@eu.citrix.com>
Release-Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
There is a bug in commit 5e4b419966 ("xen: credit2: only reset
credit on reset condition"). In fact, the aim of that commit was to
make sure that we do not perform too many credit reset operations
(which are not super cheap, and in an hot-path). But the check used
to determine whether a reset is necessary was the wrong one.
In fact, knowing just that some vCPUs have been skipped, while
traversing the runqueue (in runq_candidate()), is not enough. We
need to check explicitly whether the first vCPU in the runqueue
has a negative amount of credit.
Since a trace record is changed, this patch updates xentrace format file
and xenalyze as well
This should be backported.
Signed-off-by: Dario Faggioli <dfaggioli@suse.com>
Acked-by: George Dunlap <george.dunlap@citrix.com>
There have been report of stalls of guest vCPUs, when Credit2 was used.
It seemed like these vCPUs were not getting scheduled for very long
time, even under light load conditions (e.g., during dom0 boot).
Investigations led to the discovery that --although rarely-- it can
happen that a vCPU manages to run for very long timeslices. In Credit2,
this means that, when runtime accounting happens, the vCPU will lose a
large quantity of credits. This in turn may lead to the vCPU having less
credits than the idle vCPUs (-2^30). At this point, the scheduler will
pick the idle vCPU, instead of the ready to run vCPU, for a few
"epochs", which often times is enough for the guest kernel to think the
vCPU is not responding and crashing.
An example of this situation is shown here. In fact, we can see d0v1
sitting in the runqueue while all the CPUs are idle, as it has
-1254238270 credits, which is smaller than -2^30 = −1073741824:
(XEN) Runqueue 0:
(XEN) ncpus = 28
(XEN) cpus = 0-27
(XEN) max_weight = 256
(XEN) pick_bias = 22
(XEN) instload = 1
(XEN) aveload = 293391 (~111%)
(XEN) idlers: 00,00000000,00000000,00000000,00000000,00000000,0fffffff
(XEN) tickled: 00,00000000,00000000,00000000,00000000,00000000,00000000
(XEN) fully idle cores: 00,00000000,00000000,00000000,00000000,00000000,0fffffff
[...]
(XEN) Runqueue 0:
(XEN) CPU[00] runq=0, sibling=00,..., core=00,...
(XEN) CPU[01] runq=0, sibling=00,..., core=00,...
[...]
(XEN) CPU[26] runq=0, sibling=00,..., core=00,...
(XEN) CPU[27] runq=0, sibling=00,..., core=00,...
(XEN) RUNQ:
(XEN) 0: [0.1] flags=0 cpu=5 credit=-1254238270 [w=256] load=262144 (~100%)
We certainly don't want, under any circumstance, this to happen.
Let's, therefore, define a minimum amount of credits a vCPU can have.
During accounting, we make sure that, for however long the vCPU has
run, it will never get to have less than such minimum amount of
credits. Then, we set the credits of the idle vCPU to an even
smaller value.
NOTE: investigations have been done about _how_ it is possible for a
vCPU to execute for so much time that its credits becomes so low. While
still not completely clear, there are evidence that:
- it only happens very rarely,
- it appears to be both machine and workload specific,
- it does not look to be a Credit2 (e.g., as it happens when
running with Credit1 as well) issue, or a scheduler issue.
This patch makes Credit2 more robust to events like this, whatever
the cause is, and should hence be backported (as far as possible).
Reported-by: Glen <glenbarney@gmail.com>
Reported-by: Tomas Mozes <hydrapolic@gmail.com>
Signed-off-by: Dario Faggioli <dfaggioli@suse.com>
Reviewed-by: George Dunlap <george.dunlap@citrix.com>
On Arm64, system registers are always 64-bit including SCTLR_EL1.
However, Xen is assuming this is 32-bit because earlier revision of
Armv8 had the top 32-bit RES0 (see ARM DDI0595.b).
>From Armv8.5, some bits in [63:32] will be defined and allowed to be
modified by the guest. So we would effectively reset those bits to 0
after each context switch. This means the guest may not function
correctly afterwards.
Rather than resetting to 0 the bits [63:32], preserve them across
context switch.
Note that the corresponding register on Arm32 (i.e SCTLR) is always
32-bit. So we need to use register_t anywhere we deal the SCTLR{,_EL1}.
Outside interface is switched to use 64-bit to allow ABI compatibility
between 32-bit and 64-bit.
[Stefano: fix typo in commit message]
Signed-off-by: Julien Grall <julien.grall@arm.com>
Signed-off-by: Stefano Stabellini <stefanos@xilinx.com>
Reviewed-by: Volodymyr Babchuk <volodymyr.babchuk@epam.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Modified to provide building of the xenalyze binary for both ARM and
x86 platforms. The xenalyze binary is now built as part of the BIN
list for both platforms.
Signed-off-by: Benjamin Sanda <ben.sanda@dornerworks.com>
Signed-off-by: Julien Grall <julien.grall@arm.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
The per-cpu buffers for Xentrace are addressed by cpu-id, but the info
array for the buffers is sized only by number of online cpus. This
might lead to crashes when using Xentrace with smt=0.
The t_info structure has to be sized based on nr_cpu_ids.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: George Dunlap <george.dunlap@citrix.com>
Modify the xentrace utility to allow sparse cpu list resulting in not
all possible cpus having a trace buffer allocated.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: George Dunlap <george.dunlap@citrix.com>
xen-tools/libs.h currently contains a shared BUILD_BUG_ON() implementation and
is used by some tools. Extend this to include ARRAY_SIZE and clean up all the
opencoding.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
With gcc optimization enabled by:
tools: detect appropriate debug optimization level
b435014517
-Wformat-truncation throws warnings
gcc version 7.3.0
xenalyze.c: In function 'find_symbol':
xenalyze.c:382:36: error: 'snprintf' output may be truncated before the last format character [-Werror=format-truncation=]
snprintf(name, 128, "(%s +%llx)",
^
xenalyze.c:382:5: note: 'snprintf' output between 6 and 144 bytes into a destination of size 128
snprintf(name, 128, "(%s +%llx)",
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
lastname, offset);
~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
Signed-off-by: John Thomson <git@johnthomson.fastmail.com.au>
Reviewed-by: George Dunlap <george.dunlap@citrix.com>
Recent changes in xenalyze introduced INT_MIN without also adding the
required header, fix this by adding the header.
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: George Dunlap <george.dunlap@citrix.com>
Release-acked-by: Julien Grall <julien.grall@linaro.org>
This commit implements the Xen part of the cap mechanism for
Credit2.
A cap is how much, in terms of % of physical CPU time, a domain
can execute at most.
For instance, a domain that must not use more than 1/4 of
one physical CPU, must have a cap of 25%; one that must not
use more than 1+1/2 of physical CPU time, must be given a cap
of 150%.
Caps are per domain, so it is all a domain's vCPUs, cumulatively,
that will be forced to execute no more than the decided amount.
This is implemented by giving each domain a 'budget', and
using a (per-domain again) periodic timer. Values of budget
and 'period' are chosen so that budget/period is equal to the
cap itself.
Budget is burned by the domain's vCPUs, in a similar way to
how credits are.
When a domain runs out of budget, its vCPUs can't run any
longer. They can gain, when the budget is replenishment by
the timer, which event happens once every period.
Blocking the vCPUs because of lack of budget happens by
means of a new (_VPF_parked) pause flag, so that, e.g.,
vcpu_runnable() still works. This is similar to what is
done in sched_rtds.c, as opposed to what happens in
sched_credit.c, where vcpu_pause() and vcpu_unpause()
(which means, among other things, more overhead).
Note that, while adding new fields to csched2_vcpu and
csched2_dom, currently existing members are being moved
around, to achieve best placement inside cache lines.
Note also that xenalyze and tools/xentrace/format are being
updated too.
Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
DEPS_INCLUDE is currently the same as DEPS, so no functional change.
This patch is the result of this perl rune:
git-grep -l 'include.*DEPS' | xargs perl -i -pe 'next unless m/^-?include/; s/\bDEPS\b/DEPS_INCLUDE/'
I have verified that I haven't missed anything, with this rune:
git-grep '\bDEPS\b'
Reported-by: Jan Beulich <JBeulich@suse.com>
CC: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
DEPS_RM is currently the same as DEPS, so no functional change.
This patch is the result of two perl runes:
git-grep -l 'rm.*DEPS' | xargs perl -i~ -pe 'next unless m/^\t+rm\b/; s/\bDEPS\b/DEPS_RM/;'
git-grep -l 'RM.*DEPS' | xargs perl -i~ -pe 'next unless m/^\t+\$\(RM\)/; s/\bDEPS\b/DEPS_RM/;'
And editing tools/xenstat/libxenstat/Makefile by hand.
I verified that I didn't miss anything with this rune:
git-grep '\bDEPS\b' | grep -v include |less
Reported-by: Jan Beulich <JBeulich@suse.com>
CC: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Soft-affinity support is usually implemented by means
of a two step "balancing loop", where:
- during the first step, we consider soft-affinity
(if the vcpu has one);
- during the second (if we get to it), we consider
hard-affinity.
In runq_tickle(), we need to do that for checking
whether we can execute the waking vCPU on an pCPU
that is idle. In fact, we want to be sure that, if
there is an idle pCPU in the vCPU's soft affinity,
we'll use it.
If there are no such idle pCPUs, though, and we
have to check non-idle ones, we can avoid the loop
and to both hard and soft-affinity in one pass.
In fact, we can we scan runqueue and compute a
"score" for each vCPU which is running on each pCPU.
The idea is, since we may have to preempt someone:
- try to make sure that the waking vCPU will run
inside its soft-affinity,
- try to preempt someone that is running outside
of its own soft-affinity.
The value of the score is added to a trace record,
so xenalyze's code and tools/xentrace/formats are
updated accordingly.
Suggested-by: George Dunlap <george.dunlap@citrix.com>
Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Reviewed-by: George Dunlap <george.dunlap@citrix.com>
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>
Including whether we actually tried stealing a vCPU from
a given pCPU, or we skipped that one, because of lock
contention.
Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Acked-by: George Dunlap <george.dunlap@citrix.com>
We record trace information about the next timeslice when
switching to a different vcpu, but not when continuing to
run the same cpu:
csched2:schedule cpu 9, rq# 1, idle, SMT idle, tickled
csched2:runq_candidate d0v3, 0 vcpus skipped, cpu 9 was tickled
sched_switch prev d32767v9, run for 991.186us
sched_switch next d0v3, was runnable for 2.515us, next slice 10000.0us
sched_switch prev d32767v9 next d0v3 ^^^^^^^^^^^^^^^^^^^^
runstate_change d32767v9 running->runnable
...
csched2:schedule cpu 2, rq# 0, busy, not tickled
csched2:burn_credits d1v5, credit = 9996950, delta = 502913
csched2:runq_candidate d1v5, 0 vcpus skipped, no cpu was tickled
runstate_continue d1v5 running->running
?????????????
This information is quite useful; so add a trace including
that information on the 'continue_running' path as well,
like this:
csched2:schedule cpu 1, rq# 0, busy, not tickled
csched2:burn_credits d0v8, credit = 9998645, delta = 12104
csched2:runq_candidate d0v8, credit = 9998645, 0 vcpus skipped, no cpu was tickled
sched_switch continue d0v8, run for 1125.820us, next slice 9998.645us
runstate_continue d0v8 running->running ^^^^^^^^^^^^^^^^^^^^^
Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Acked-by: George Dunlap <george.dunlap@citrix.com>
When traversing a Credit2 runqueue to select the
best candidate vCPU to be run next, show in the
trace which vCPUs we consider.
A bit verbose, but quite useful, considering that
we may end up looking at, but then discarding, one
of more vCPU. This will help understand which ones
are skipped and why.
Also, add how much credits the chosen vCPU has
(in the TRC_CSCHED2_RUNQ_CANDIDATE record). And,
while there, fix a bug in tools/xentrace/formats
(still in the output of TRC_CSCHED2_RUNQ_CANDIDATE).
Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Acked-by: George Dunlap <george.dunlap@citrix.com>
For Credit2, in both the trace records, inside Xen,
and in their parsing, in xenalyze.
In fact, as it is quite a bit better, in order to
understand how much negative credits have gone for
a certain vCPU, to see an actual negative number,
as compared to a wrapped around unsigned!
Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Reviewed-by: George Dunlap <george.dunlap@citrix.com>
There are some scheduling related trace records that
are not being taken care of (and hence only dumped as
raw records).
Some of them are being introduced in this series, while
other were just neglected by previous patches.
Add support for them.
Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Acked-by: George Dunlap <george.dunlap@eu.citrix.com>
Right now, two out of the three events related to
context switch (that is TRC_SCHED_SWITCH_INFPREV and
TRC_SCHED_SWITCH_INFNEXT) only report the domain id,
and not the vcpu id.
That's omitting a useful piece of information, and
even if we be figured that out by looking at other
records, that's unnecessarily complicated (especially
if working on a trace from a sctipt).
This changes both the tracing code in Xen and the parsing
code in tools at once, to avoid introducing transitional
regressions.
Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Acked-by: George Dunlap <george.dunlap@citrix.com>
This is a side-effect of commit c36e1c, which currently prevents compiling
xenalyze with libcs that don't have argp built-in.
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: George Dunlap <george.dunlap@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Rather than have large fixed-size buffers, start with smaller buffers
and allow them to grow as needed (doubling each time), with a fairly
large maximum. Allow this maximum to be set by a command-line
parameter.
Signed-off-by: George Dunlap <george.dunlap@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
The only difference between event_cycle_summary and cycle_summary was
that the former has a separate counter for "events" which had
zero-cycle events. But a lot of the code dealing with them had to be
duplicated with slightly different fields.
Remove event_cycle_summary, add an "event_count" field to
cycle_symmary, and use cycle_summary for everything.
Signed-off-by: George Dunlap <george.dunlap@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
At the moment these structures are not used, and half of the code for
collecting it is commented out. To be used they require further
support for collecting hardware instruction counter data inside of
Xen.
Remove the code entirely; when they're wanted again they will be here
in the git log.
Signed-off-by: George Dunlap <george.dunlap@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
xenalyze was inheriting LDLIBS of xentrace; but it doesn't need them.
Remove this dependency, which allows xenalyze to be built without the libraries
having been built, and run without the libraries being installed.
Signed-off-by: George Dunlap <george.dunlap@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Dario Faggioli <dario.faggioli@citrix.com>
In fact, 52cf096df7 ("xenalyze: handle scheduling event"),
when dealing with TRC_SCHED_SWITCH, forgot to check whether
we actually are in dump mode, causing the printf() in
dump_sched_switch() to always produce its output, which
is not what we want.
Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Acked-by: George Dunlap <george.dunlap@citrix.com>
more specifically, with: TICKLE_NEW, RUNQ_MAX_WEIGHT,
MIGRATE, LOAD_CHECK, LOAD_BALANCE and PICKED_CPU, and
in both both xenalyze and formats (for xentrace_format).
Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Acked-by: George Dunlap <george.dunlap@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Add the shift used for the precision of the integer
arithmetic to the trace records, and update both xenalyze
and xentrace_format to make use of/print it.
In particular, in xenalyze, we are can now show the
load as a (easier to interpreet) percentage.
Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Reviewed-by: George Dunlap <george.dunlap@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
(i.e., domain creation and destruction) so the
trace will show properly decoded info, rather
than just a bunch of hex codes.
Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Acked-by: George Dunlap <george.dunlap@citrix.com>
We change the xen_version libxc code to use the new hypercall.
Which of course means every user in the code base has to
be changed over.
It is important to note that the xc_version_op has a different
return semantic than the previous one. It returns negative
values on error (like the old one), but it also returns
an positive value on success (unlike the old one). The positive
value is the number of bytes copied in.
Note that both Ocaml and xenstat use tabs instead of four
spaces so they look quite odd.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Tested-by: Andrew Cooper <andrew.cooper3@citrix.com> [for the Ocaml stubs]
Acked-by: George Dunlap <george.dunlap@eu.citrix.com> [xenctx bits]
Acked-by: Wei Liu <wei.liu2@citrix.com>
to include the vcpu IDs, in a way that matches
how the "dom:vcpu" couple is displayed in other
events (runstate changes).
Also add the trace for TRC_SCHED_SHUTDOWN_CODE which
was missing and was done via SCHEDOP_shutdown_code hypercall.
(TRC_SCHED_SHUTDOWN trace was present).
Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
---
Cc: George Dunlap <george.dunlap@eu.citrix.com>
Cc: Ian Jackson <ian.jackson@eu.citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Wei Liu <wei.liu2@citrix.com>
Cc: Olaf Hering <olaf@aepfle.de>
---
Changes from v1:
* enhanced changelog, as suggested during review.
find_vec() is supposed to find the vector in the list if it exists,
choose an empty slot if it doesn't exist, and return null if all slots
are full.
However, coverity noticed that although the callers of find_vec() handle
the last condition, find_vec() itself didn't.
Check to see if we actually found an empty slot before attempting to
initialize it.
CID 1306864
Signed-off-by: George Dunlap <george.dunlap@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Bertrand Marquis
Julien Grall
Manuel Bouyer
Dario Faggioli
Julien Grall
Benjamin Sanda
Ian Jackson
Juergen Gross
Andrew Cooper
John Thomson
Roger Pau Monne
Dario Faggioli
Ian Jackson
George Dunlap
Petre Pircalabu
Alistair Francis
Konrad Rzeszutek Wilk
George Dunlap