Commit graph

644 commits

Author SHA1 Message Date
Emilio G. Cota 1677898a09
cputlb: read CPUTLBEntry.addr_write atomically
Updates can come from other threads, so readers that do not
take tlb_lock must use atomic_read to avoid undefined
behaviour (UB).

This completes the conversion to tlb_lock. This conversion results
on average in no performance loss, as the following experiments
(run on an Intel i7-6700K CPU @ 4.00GHz) show.

1. aarch64 bootup+shutdown test:

- Before:
Performance counter stats for 'taskset -c 0 ../img/aarch64/die.sh' (10 runs):

7487.087786 task-clock (msec) # 0.998 CPUs utilized ( +- 0.12% )
31,574,905,303 cycles # 4.217 GHz ( +- 0.12% )
57,097,908,812 instructions # 1.81 insns per cycle ( +- 0.08% )
10,255,415,367 branches # 1369.747 M/sec ( +- 0.08% )
173,278,962 branch-misses # 1.69% of all branches ( +- 0.18% )

7.504481349 seconds time elapsed ( +- 0.14% )

- After:
Performance counter stats for 'taskset -c 0 ../img/aarch64/die.sh' (10 runs):

7462.441328 task-clock (msec) # 0.998 CPUs utilized ( +- 0.07% )
31,478,476,520 cycles # 4.218 GHz ( +- 0.07% )
57,017,330,084 instructions # 1.81 insns per cycle ( +- 0.05% )
10,251,929,667 branches # 1373.804 M/sec ( +- 0.05% )
173,023,787 branch-misses # 1.69% of all branches ( +- 0.11% )

7.474970463 seconds time elapsed ( +- 0.07% )

2. SPEC06int:
SPEC06int (test set)
[Y axis: Speedup over master]
1.15 +-+----+------+------+------+------+------+-------+------+------+------+------+------+------+----+-+
| |
1.1 +-+.................................+++.............................+ tlb-lock-v2 (m+++x) +-+
| +++ | +++ tlb-lock-v3 (spinl|ck) |
| +++ | | +++ +++ | | |
1.05 +-+....+++...........####.........|####.+++.|......|.....###....+++...........+++....###.........+-+
| ### ++#| # |# |# ***### +++### +++#+# | +++ | #|# ### |
1 +-+++***+#++++####+++#++#++++++++++#++#+*+*++#++++#+#+****+#++++###++++###++++###++++#+#++++#+#+++-+
| *+* # #++# *** # #### *** # * *++# ****+# *| * # ****|# |# # #|# #+# # # |
0.95 +-+..*.*.#....#..#.*|*..#...#..#.*|*..#.*.*..#.*|.*.#.*++*.#.*++*+#.****.#....#+#....#.#..++#.#..+-+
| * * # # # *|* # # # *|* # * * # *++* # * * # * * # * |* # ++# # # # *** # |
| * * # ++# # *+* # # # *|* # * * # * * # * * # * * # *++* # **** # ++# # * * # |
0.9 +-+..*.*.#...|#..#.*.*..#.++#..#.*|*..#.*.*..#.*..*.#.*..*.#.*..*.#.*..*.#.*.|*.#...|#.#..*.*.#..+-+
| * * # *** # * * # |# # *+* # * * # * * # * * # * * # * * # *++* # |# # * * # |
0.85 +-+..*.*.#..*|*..#.*.*..#.***..#.*.*..#.*.*..#.*..*.#.*..*.#.*..*.#.*..*.#.*..*.#.****.#..*.*.#..+-+
| * * # *+* # * * # *|* # * * # * * # * * # * * # * * # * * # * * # * |* # * * # |
| * * # * * # * * # *+* # * * # * * # * * # * * # * * # * * # * * # * |* # * * # |
0.8 +-+..*.*.#..*.*..#.*.*..#.*.*..#.*.*..#.*.*..#.*..*.#.*..*.#.*..*.#.*..*.#.*..*.#.*++*.#..*.*.#..+-+
| * * # * * # * * # * * # * * # * * # * * # * * # * * # * * # * * # * * # * * # |
0.75 +-+--***##--***###-***###-***###-***###-***###-****##-****##-****##-****##-****##-****##--***##--+-+
400.perlben401.bzip2403.gcc429.m445.gob456.hmme45462.libqua464.h26471.omnet473483.xalancbmkgeomean

png: https://imgur.com/a/BHzpPTW

Notes:
- tlb-lock-v2 corresponds to an implementation with a mutex.
- tlb-lock-v3 corresponds to the current implementation, i.e.
a spinlock and a single lock acquisition in tlb_set_page_with_attrs.

Backports commit 403f290c0603f35f2d09c982bf5549b6d0803ec1 from qemu
2018-10-23 15:37:43 -04:00
Richard Henderson d74e00a30a
tcg: Split CONFIG_ATOMIC128
GCC7+ will no longer advertise support for 16-byte __atomic operations
if only cmpxchg is supported, as for x86_64. Fortunately, x86_64 still
has support for __sync_compare_and_swap_16 and we can make use of that.
AArch64 does not have, nor ever has had such support, so open-code it.

Backports commit e6cd4bb59b8154fa00da611200beef7eb4e8ec56 from qemu
2018-10-23 15:17:39 -04:00
Richard Henderson c911ea7128
tcg: Add tlb_index and tlb_entry helpers
Isolate the computation of an index from an address into a
helper before we change that function.

Backports commit 383beda9cf32f795616c3b93f7d6154d70372d4b from qemu
2018-10-23 15:04:27 -04:00
Emilio G. Cota dfb3954571
exec: introduce tlb_init
Paves the way for the addition of a per-TLB lock.

Backports commit 5005e2537d090bee87aca3b924dcd17920fd146a from qemu
2018-10-23 14:41:29 -04:00
Emilio G. Cota 9f08fb35bc
softfloat: remove float64_trunc_to_int
It has not had users since f83311e476 ("target-m68k: use floatx80
internally", 2017-06-21).

Note that no other bit-width has floatX_trunc_to_int.

Backports commit c953da8f0be5e026d1c9128660736d72294feb3e from qemu
2018-10-08 14:15:11 -04:00
Peter Maydell 01683fe97e
memory: Remove old_mmio accessors
Now that all the users of old_mmio MemoryRegion accessors
have been converted, we can remove the core code support.

Backports commit 62a0db942dec6ebfec19aac2b604737d3c9a2d75 from qemu
2018-10-04 04:45:30 -04:00
Emilio G. Cota f3f22c94e1
atomic: fix comment s/x64_64/x86_64/
Backports commit 119c440c3c599778bfb4f90d8e39fda132925813 from qemu
2018-10-04 00:44:48 -04:00
Lioncash a97d643944
qemu/int128: Disable assert in int128.h
This mirrors the int128_get64() variant for the case when CONFIG_INT128
is not defined as 1, which was pre-existing in unicorn.
2018-09-03 09:54:59 -04:00
Richard Henderson 0d69492b64
softfloat: Add scaling float-to-int routines
Backports commit 2f6c74be593ec5219e54d7b4abd4e5a98d7f3efc from qemu
2018-08-25 04:05:45 -04:00
Richard Henderson ee0d8aff72
softfloat: Add scaling int-to-float routines
Backports commit 2abdfe24402907e7e8c103bdd4166f26b74200c2 from qemu
2018-08-25 03:47:12 -04:00
Junyan He 6ead2c3d1f
memory, exec: Expose all memory block related flags.
We need to use these flags in other files rather than just in exec.c,
For example, RAM_SHARED should be used when create a ram block from file.
We expose them the exec/memory.h

Backports commit b0e5de93811077254a536c23b713b49e12efb742 from qemu
2018-08-22 13:00:05 -04:00
liujunjie ea6ea4313d
qstring: Fix qstring_from_substr() not to provoke int overflow
qstring_from_substr() parameters @start and @end are of type int.
blkdebug_parse_filename(), blkverify_parse_filename(), nbd_parse_uri(),
and qstring_from_str() pass @end values of type size_t or ptrdiff_t.
Values exceeding INT_MAX get truncated, with possibly disastrous
results.

Such huge substrings seem unlikely, but we found one in a core dump,
where "info tlb" executed via QMP's human-monitor-command apparently
produced 35 GiB of output.

Fix by changing the parameters size_t.

Backports commit ad63c549ecd4af4a22a675a815edeb06b0e7bb6e from qemu
2018-08-02 21:21:51 -04:00
Philippe Mathieu-Daudé 26948b6b98
include: Add IEC binary prefixes in qemu/units.h
Loosely based on 076b35b5a56.

Backports commit 7ecdc94c40f4958a66893c0eac423c6a80f376d4 from qemu
2018-07-03 19:47:19 -04:00
Richard Henderson 8bd115214d
cpu: Assert asidx_from_attrs return value in range
Backports commit 9c8c334b0637bf3c592d432b0c11f3b62dd5dba3 from qemu
2018-07-03 19:43:59 -04:00
Peter Maydell 6543f9ea26
tcg: Define and use new tlb_hit() and tlb_hit_page() functions
The condition to check whether an address has hit against a particular
TLB entry is not completely trivial. We do this in various places, and
in fact in one place (get_page_addr_code()) we have got the condition
wrong. Abstract it out into new tlb_hit() and tlb_hit_page() inline
functions (one for a known-page-aligned address and one for an
arbitrary address), and use them in all the places where we had the
condition correct.

This is a no-behaviour-change patch; we leave fixing the buggy
code in get_page_addr_code() to a subsequent patch

Backports commit 334692bce7f0653a93b8d84ecde8c847b08dec38 from qemu
2018-07-03 19:21:36 -04:00
Paolo Bonzini b7e2e6ec04
osdep: work around Coverity parsing errors
Coverity does not like the new _Float* types that are used by
recent glibc, and croaks on every single file that includes
stdlib.h. Add dummy typedefs to please it.

Backports commit a1a98357e3fdfce92b5ed0c6728489b9992fecb5 from qemu
2018-07-03 01:23:39 -04:00
Stefan Hajnoczi e8b92838fe
compiler: add a sizeof_field() macro
Determining the size of a field is useful when you don't have a struct
variable handy. Open-coding this is ugly.

This patch adds the sizeof_field() macro, which is similar to
typeof_field(). Existing instances are updated to use the macro.

Backports commit f18793b096e69c7acfce66cded483ba9fc01762a from qemu
2018-07-03 01:02:54 -04:00
Babu Moger b5f47a4884
i386: Fix up the Node id for CPUID_8000_001E
This is part of topoext support. To keep the compatibility, it is better
we support all the combination of nr_cores and nr_threads currently
supported. By allowing more nr_cores and nr_threads, we might end up with
more nodes than we can actually support with the real hardware. We need to
fix up the node id to make this work. We can achieve this by shifting the
socket_id bits left to address more nodes.

Backports commit 631be32155dbafa1fe886f2488127956c9120ba6 from qemu
2018-07-03 00:31:38 -04:00
Peter Maydell 8295b228e3
bswap: Add new stn_*_p() and ldn_*_p() memory access functions
There's a common pattern in QEMU where a function needs to perform
a data load or store of an N byte integer in a particular endianness.
At the moment this is handled by doing a switch() on the size and
calling the appropriate ld*_p or st*_p function for each size.

Provide a new family of functions ldn_*_p() and stn_*_p() which
take the size as an argument and do the switch() themselves.

Backports commit afa4f6653dca095f63f3fe7f2001e9334f5676c1 from qemu
2018-06-15 12:17:21 -04:00
Peter Maydell 61a7ac6948
cpu-defs.h: Document CPUIOTLBEntry 'addr' field
The 'addr' field in the CPUIOTLBEntry struct has a rather non-obvious
use; add a comment documenting it (reverse-engineered from what
the code that sets it is doing).

Backports commit ace4109011b4912b24e76f152e2cf010e78819c5 from qemu
2018-06-15 12:07:39 -04:00
Peter Maydell 7a6ae26346
cputlb: Pass cpu_transaction_failed() the correct physaddr
The API for cpu_transaction_failed() says that it takes the physical
address for the failed transaction. However we were actually passing
it the offset within the target MemoryRegion. We don't currently
have any target CPU implementations of this hook that require the
physical address; fix this bug so we don't get confused if we ever
do add one.

Backports commit 2d54f19401bc54b3b56d1cc44c96e4087b604b97 from qemu
2018-06-15 12:03:23 -04:00
Richard Henderson 10e2b13650
tcg: Pass tb and index to tcg_gen_exit_tb separately
Do the cast to uintptr_t within the helper, so that the compiler
can type check the pointer argument. We can also do some more
sanity checking of the index argument.

Backports commit 07ea28b41830f946de3841b0ac61a3413679feb9 from qemu
2018-06-07 11:56:32 -04:00
Richard Henderson 533a3f6a6c
tcg: Fix helper function vs host abi for float16
Depending on the host abi, float16, aka uint16_t, values are
passed and returned either zero-extended in the host register
or with garbage at the top of the host register.

The tcg code generator has so far been assuming garbage, as that
matches the x86 abi, but this is incorrect for other host abis.
Further, target/arm has so far been assuming zero-extended results,
so that it may store the 16-bit value into a 32-bit slot with the
high 16-bits already clear.

Rectify both problems by mapping "f16" in the helper definition
to uint32_t instead of (a typedef for) uint16_t. This forces
the host compiler to assume garbage in the upper 16 bits on input
and to zero-extend the result on output.

Backports commit 6c2be133a7478e443c99757b833d0f265c48e0a6 from qemu
2018-06-02 10:10:12 -04:00
Philippe Mathieu-Daudé 752fd5dd12
typedefs: Remove PcGuestInfo from qemu/typedefs.h
It is long gone since e4e8ba04c2007 ...

Backports commit 201376cb9e500f64209444cb95f566679c0f54a2 from qemu
2018-05-22 00:32:07 -04:00
Richard Henderson 1730d3cff0
target/arm: Implement SVE Integer Multiply-Add Group
Backports commit 96a36e4a44bbf296ac212ed68ebf4e48d3dfb1f0 from qemu
2018-05-20 04:35:36 -04:00
Richard Henderson 79a4c4ed0f
fpu/softfloat: Specialize on snan_bit_is_one
Only MIPS requires snan_bit_is_one to be variable. While we are
specializing softfloat behaviour, allow other targets to eliminate
this runtime check.

Backports commit 03385dfdaaa2dc31bbd07d13244a6b037bfab4cc from qemu
2018-05-19 23:38:58 -04:00
Alex Bennée f1f2521b38
fpu/softfloat: re-factor float to float conversions
This allows us to delete a lot of additional boilerplate
code which is no longer needed.

Backports commit 6fed16b265a4fcc810895bbca4d67e1ae7a89f07 from qemu
2018-05-19 23:16:58 -04:00
Richard Henderson ff8fab55a2
fpu/softfloat: Split floatXX_silence_nan from floatXX_maybe_silence_nan
The new function assumes that the input is an SNaN and
does not double-check.

Backports commit d619bb98fdcda24f9ee3b7a53a4d555228dbca52 from qemu
2018-05-19 22:06:33 -04:00
Peter Maydell 3dddb8564f
tcg: Optionally log FPU state in TCG -d cpu logging
Usually the logging of the CPU state produced by -d cpu is sufficient
to diagnose problems, but sometimes you want to see the state of
the floating point registers as well. We don't want to enable that
by default as it adds a lot of extra data to the log; instead,
allow it to be optionally enabled via -d fpu.

Backports relevant parts of commit ae7651804748c6b479d5ae09aeac4edb9c44f76e from qemu
2018-05-15 22:31:08 -04:00
Peter Maydell b22f822858
atomic.h: Work around gcc spurious "unused value" warning
Some versions of gcc produce a spurious warning if the result of
__atomic_compare_echange_n() is not used and the type involved
is a signed 8 bit value:
error: value computed is not used [-Werror=unused-value]
This has been seen on at least
gcc (Ubuntu 5.4.0-6ubuntu1~16.04.9) 5.4.0 20160609

Work around this by using an explicit cast to void to indicate
that we don't care about the return value.

We don't currently use our atomic_cmpxchg() macro on any signed
8 bit types, but the upcoming support for the Arm v8.1-Atomics
will require it.

Backports commit cd95fc28fb6d8afced0d70ce52c294d0761a9daa from qemu
2018-05-14 07:26:40 -04:00
Emilio G. Cota d26bf1d446
translator: merge max_insns into DisasContextBase
While at it, use int for both num_insns and max_insns to make
sure we have same-type comparisons.

Backports commit b542683d77b4f56cef0221b267c341616d87bce9 from qemu
2018-05-11 13:59:17 -04:00
Marc-André Lureau 0087625b7e
qobject: Modify qobject_ref() to return obj
For convenience and clarity, make it possible to call qobject_ref() at
the time when the reference is associated with a variable, or
argument, by making qobject_ref() return the same pointer as given.
Use that to simplify the callers.

Backports commit f5a74a5a50387c6f980b2e2f94f062487a1826da from qemu
2018-05-04 10:24:10 -04:00
Marc-André Lureau ab4528c1e4
qobject: Replace qobject_incref/QINCREF qobject_decref/QDECREF
Now that we can safely call QOBJECT() on QObject * as well as its
subtypes, we can have macros qobject_ref() / qobject_unref() that work
everywhere instead of having to use QINCREF() / QDECREF() for QObject
and qobject_incref() / qobject_decref() for its subtypes.

The replacement is mechanical, except I broke a long line, and added a
cast in monitor_qmp_cleanup_req_queue_locked(). Unlike
qobject_decref(), qobject_unref() doesn't accept void *.

Note that the new macros evaluate their argument exactly once, thus no
need to shout them.

Backports commit cb3e7f08aeaab0ab13e629ce8496dca150a449ba from qemu
2018-05-04 10:16:07 -04:00
Marc-André Lureau f4b3c5d0bd
qobject: use a QObjectBase_ struct
By moving the base fields to a QObjectBase_, QObject can be a type
which also has a 'base' field. This allows writing a generic QOBJECT()
macro that will work with any QObject type, including QObject
itself. The container_of() macro ensures that the object to cast has a
QObjectBase_ base field, giving some type safety guarantees. QObject
must have no members but QObjectBase_ base, or else QOBJECT() breaks.

QObjectBase_ is not a typedef and uses a trailing underscore to make
it obvious it is not for normal use and to avoid potential abuse.

Backports commit 3d3eacaeccaab718ea0e2ddaa578bfae9e311c59 from qemu
2018-05-04 10:11:24 -04:00
Marc-André Lureau 2ca916e106
qobject: Ensure base is at offset 0
All QObject types have the base QObject as their first field. This
allows the simplification of qobject_to().

Backports commit 7ee9edfdb117da47c86c9764d90f0be11a648666 from qemu
2018-05-04 09:54:36 -04:00
Pavel Dovgalyuk b4bf3c776b
icount: fix cpu_restore_state_from_tb for non-tb-exit cases
In icount mode, instructions that access io memory spaces in the middle
of the translation block invoke TB recompilation. After recompilation,
such instructions become last in the TB and are allowed to access io
memory spaces.

When the code includes instruction like i386 'xchg eax, 0xffffd080'
which accesses APIC, QEMU goes into an infinite loop of the recompilation.

This instruction includes two memory accesses - one read and one write.
After the first access, APIC calls cpu_report_tpr_access, which restores
the CPU state to get the current eip. But cpu_restore_state_from_tb
resets the cpu->can_do_io flag which makes the second memory access invalid.
Therefore the second memory access causes a recompilation of the block.
Then these operations repeat again and again.

This patch moves resetting cpu->can_do_io flag from
cpu_restore_state_from_tb to cpu_loop_exit* functions.

It also adds a parameter for cpu_restore_state which controls restoring
icount. There is no need to restore icount when we only query CPU state
without breaking the TB. Restoring it in such cases leads to the
incorrect flow of the virtual time.

In most cases new parameter is true (icount should be recalculated).
But there are two cases in i386 and openrisc when the CPU state is only
queried without the need to break the TB. This patch fixes both of
these cases.

Backports commit afd46fcad2dceffda35c0586f5723c127b6e09d8 from qemu
2018-04-11 20:05:40 -04:00
Alex Bennée 4074587775
accel/tcg/translate-all: expand cpu_restore_state addr check
We are still seeing signals during translation time when we walk over
a page protection boundary. This expands the check to ensure the host
PC is inside the code generation buffer. The original suggestion was
to check versus tcg_ctx.code_gen_ptr but as we now segment the
translation buffer we have to settle for just a general check for
being inside.

I've also fixed up the declaration to make it clear it can deal with
invalid addresses. A later patch will fix up the call sites.

Backports commit d25f2a72272b9ffe0d06710d6217d1169bc2cc7d from qemu
2018-04-11 19:53:57 -04:00
Bharata B Rao 309b85548f
cpu: Convert cpu_index into a bitmap
Currently CPUState::cpu_index is monotonically increasing and a newly
created CPU always gets the next higher index. The next available
index is calculated by counting the existing number of CPUs. This is
fine as long as we only add CPUs, but there are architectures which
are starting to support CPU removal, too. For an architecture like PowerPC
which derives its CPU identifier (device tree ID) from cpu_index, the
existing logic of generating cpu_index values causes problems.

With the currently proposed method of handling vCPU removal by parking
the vCPU fd in QEMU
(Ref: http://lists.gnu.org/archive/html/qemu-devel/2015-02/msg02604.html),
generating cpu_index this way will not work for PowerPC.

This patch changes the way cpu_index is handed out by maintaining
a bit map of the CPUs that tracks both addition and removal of CPUs.

The CPU bitmap allocation logic is part of cpu_exec_init(), which is
called by instance_init routines of various CPU targets. Newly added
cpu_exec_exit() API handles the deallocation part and this routine is
called from generic CPU instance_finalize.

Note: This new CPU enumeration is for !CONFIG_USER_ONLY only.
CONFIG_USER_ONLY continues to have the old enumeration logic.

Backports commit b7bca7333411bd19c449147e8202ae6b0e4a8e09 from qemu
2018-03-21 08:06:07 -04:00
Bharata B Rao e373c001fa
cpu: Add Error argument to cpu_exec_init()
Add an Error argument to cpu_exec_init() to let users collect the
error. This is in preparation to change the CPU enumeration logic
in cpu_exec_init(). With the new enumeration logic, cpu_exec_init()
can fail if cpu_index values corresponding to max_cpus have already
been handed out.

Since all current callers of cpu_exec_init() are from instance_init,
use error_abort Error argument to abort in case of an error.

Backports commit 5a790cc4b942e651fec7edc597c19b637fad5a76 from qemu
2018-03-21 07:50:33 -04:00
Igor Mammedov f8eeacb280
Use cpu_create(type) instead of cpu_init(cpu_model)
With all targets defining CPU_RESOLVING_TYPE, refactor
cpu_parse_cpu_model(type, cpu_model) to parse_cpu_model(cpu_model)
so that callers won't have to know internal resolving cpu
type. Place it in exec.c so it could be called from both
target independed vl.c and *-user/main.c.

That allows us to stop abusing cpu type from
MachineClass::default_cpu_type
as resolver class in vl.c which were confusing part of
cpu_parse_cpu_model().

Also with new parse_cpu_model(), the last users of cpu_init()
in null-machine.c and bsd/linux-user targets could be switched
to cpu_create() API and cpu_init() API will be removed by
follow up patch.

With no longer users left remove MachineState::cpu_model field,
new code should use MachineState::cpu_type instead and
leave cpu_model parsing to generic code in vl.c.

Backports commit 2278b93941d42c30e2950d4b8dff4943d064e7de from qemu
2018-03-20 14:20:30 -04:00
Igor Mammedov 733d60e6d7
vl.c: convert cpu_model to cpu type and set of global properties before machine_init()
All machines that support user specified cpu_model either call
cpu_generic_init() or cpu_class_by_name()/CPUClass::parse_features
to parse feature string and to get CPU type to create.

Which leads to code duplication and hard-codding default CPU model
within machine_foo_init() code. Which makes it impossible to
get CPU type before machine_init() is run.

So instead of setting default CPUs models and doing parsing in
target specific machine_foo_init() in various ways, provide
a generic data driven cpu_model parsing before machine_init()
is called.

in follow up per target patches, it will allow to:
* define default CPU type in consistent/generic manner
per machine type and drop custom code that fallbacks
to default if cpu_model is NULL
* drop custom features parsing in targets and do it
in centralized way.
* for cases of
cpu_generic_init(TYPE_BASE/DEFAULT_CPU, "some_cpu")
replace it with
cpu_create(machine->cpu_type) || cpu_create(TYPE_FOO)
depending if CPU type is user settable or not.
not doing useless parsing and clearly documenting where
CPU model is user settable or fixed one.

Patch allows machine subclasses to define default CPU type
per machine class at class_init() time and if that is set
generic code will parse cpu_model into a MachineState::cpu_type
which will be used to create CPUs for that machine instance
and allows gradual per board conversion.

Backports commit 6063d4c0f98b35a27ca018393d328a1825412a7e from qemu
2018-03-20 13:15:21 -04:00
Igor Mammedov 555eeb4120
qom: cpus: split cpu_generic_init() on feature parsing and cpu creation parts
it would allow to reuse feature parsing part in various machines
that have CPU features instead of re-implementing the same feature
parsing each time.

Backports commit 3c72234c98004a01d79a24f78b07053cfebd0f22 from qemu
2018-03-20 13:09:04 -04:00
Igor Mammedov 9c5153270f
i386: keep cpu_model field in MachineState uptodate
Considering that features are converted to global properties and
global properties are automatically applied to every new instance
of created CPU (at object_new() time), there is no point in
parsing cpu_model string every time a CPU created. So move
parsing outside CPU creation loop and do it only once.

Parsing also should be done before any CPU is created so that
features would affect the first CPU a well.

Backports commit 6aff24c6a61c6fec31e555c7748ba6085b7b2c06 from qemu
2018-03-20 12:40:35 -04:00
Igor Mammedov 87db6e033b
cpu: Use CPUClass->parse_features() as convertor to global properties
Currently CPUClass->parse_features() is used to parse -cpu
features string and set properties on created CPU instances.

But considering that features specified by -cpu apply to every
created CPU instance, it doesn't make sense to parse the same
features string for every CPU created. It also makes every target
that cares about parsing features string explicitly call
CPUClass->parse_features() parser, which gets in a way if we
consider using generic device_add for CPU hotplug as device_add
has not a clue about CPU specific hooks.

Turns out we can use global properties mechanism to set
properties on every created CPU instance for a given type. That
way it's possible to convert CPU features into a set of global
properties for CPU type specified by -cpu cpu_model and common
Device.device_post_init() will apply them to CPU of given type
automatically regardless whether it's manually created CPU or CPU
created with help of device_add.

Backports commits 62a48a2a5798425997152dea3fc48708f9116c04 and
f313369fdb78f849ecbbd8e5d88f01ddf38786c8 from qemu
2018-03-20 12:00:27 -04:00
Peter Xu a6ee6f1a87
qobject: introduce qobject_get_try_str()
A quick way to fetch string from qobject when it's a QString.

Backports commit b26ae1cb8eb0756524e322169138830b9b542311 from qemu
2018-03-20 11:10:03 -04:00
Peter Xu 6446b66dc7
qobject: introduce qstring_get_try_str()
The only difference from qstring_get_str() is that it allows the qstring
to be NULL. If so, NULL is returned.

Backports commit 775932020dd6bd7e9c1acc0d7779677d8b4c094c from qemu
2018-03-20 11:08:40 -04:00
Max Reitz 0c71b44d41
qapi: Remove qobject_to_X() functions
They are no longer needed now.

Backports commit cb51b976babf7ee16dc5eda4f2189d65b8b700a3 from qemu
2018-03-20 10:58:44 -04:00
Max Reitz dbdba16732
qapi: Add qobject_to()
This is a dynamic casting macro that, given a QObject type, returns an
object as that type or NULL if the object is of a different type (or
NULL itself).

The macro uses lower-case letters because:
1. There does not seem to be a hard rule on whether qemu macros have to
be upper-cased,
2. The current situation in qapi/qmp is inconsistent (compare e.g.
QINCREF() vs. qdict_put()),
3. qobject_to() will evaluate its @obj parameter only once, thus it is
generally not important to the caller whether it is a macro or not,
4. I prefer it aesthetically.

The macro parameter order is chosen with typename first for
consistency with other QAPI macros like QAPI_CLONE(), as well as
for legibility (read it as "qobject to" type "applied to" obj).

Backports commit 1a56b1e2ab5e9d6d89386ca953b4afb419e15abe from qemu
2018-03-20 10:45:59 -04:00
Max Reitz 6acf9baa68
compiler: Add QEMU_BUILD_BUG_MSG() macro
_Static_assert() allows us to specify messages, and that may come in
handy. Even without _Static_assert(), encouraging developers to put a
helpful message next to the QEMU_BUILD_BUG_* may make debugging easier
whenever it breaks.

Backports commit 9139b5672360aaa263da1d96cdfdbe16accb6e3b from qemu
2018-03-20 10:43:37 -04:00
Andreas Grapentin 4f6ba5a2dc
use _Static_assert in QEMU_BUILD_BUG_ON
QEMU_BUILD_BUG_ON should use C11's _Static_assert, if the compiler supports it,
to provide more readable messages on failure.

We check for _Static_assert in configure, and set CONFIG_STATIC_ASSERT
accordingly. QEMU_BUILD_BUG_ON invokes _Static_assert if CONFIG_STATIC_ASSERT
is defined, and reverts to the old way otherwise.

That way, systems without C11 conforming compiler will still have the old
messages, as verified by intentionally breaking the configure check.

the following example output was generated by inverting the condition in
QEMU_BUILD_BUG_ON:

without _Static_assert:

> In file included from /qemu/include/qemu/osdep.h:36:0,
> from /qemu/qga/commands.c:13:
> /qemu/qga/commands.c: In function ‘qmp_guest_exec_status’:
> /qemu/include/qemu/compiler.h:89:12: error: negative width in bit-field ‘<anonymous>’
> struct { \
> ^
> /qemu/include/qemu/compiler.h:96:38: note: in expansion of macro QEMU_BUILD_BUG_ON_STRUCT’
> #define QEMU_BUILD_BUG_ON(x) typedef QEMU_BUILD_BUG_ON_STRUCT(x) \
> ^~~~~~~~~~~~~~~~~~~~~~~~
> /qemu/include/qemu/atomic.h:146:5: note: in expansion of macro ‘QEMU_BUILD_BUG_ON’
> QEMU_BUILD_BUG_ON(sizeof(*ptr) > sizeof(void *)); \
> ^~~~~~~~~~~~~~~~~
> /qemu/include/qemu/atomic.h:417:5: note: in expansion of macro ‘atomic_load_acquire’
> atomic_load_acquire(ptr)
> ^~~~~~~~~~~~~~~~~~~
> /qemu/qga/commands.c:160:21: note: in expansion of macro ‘atomic_mb_read’
> bool finished = atomic_mb_read(&gei->finished);
> ^~~~~~~~~~~~~~

with _Static_assert:

> In file included from /qemu/include/qemu/osdep.h:36:0,
> from /qemu/qga/commands.c:13:
> /qemu/qga/commands.c: In function ‘qmp_guest_exec_status’:
> /qemu/include/qemu/compiler.h:94:30: error: static assertion failed: "not expecting: sizeof(*&gei->finished) > sizeof(void *)"
> #define QEMU_BUILD_BUG_ON(x) _Static_assert((x), #x)
> ^
> /qemu/include/qemu/atomic.h:146:5: note: in expansion of macro ‘QEMU_BUILD_BUG_ON’
> QEMU_BUILD_BUG_ON(sizeof(*ptr) > sizeof(void *)); \
> ^~~~~~~~~~~~~~~~~
> /qemu/include/qemu/atomic.h:417:5: note: in expansion of macro ‘atomic_load_acquire’
> atomic_load_acquire(ptr)
> ^~~~~~~~~~~~~~~~~~~
> /qemu/qga/commands.c:160:21: note: in expansion of macro ‘atomic_mb_read’
> bool finished = atomic_mb_read(&gei->finished);
> ^~~~~~~~~~~~~~

Backports commit 49e00a18708e27c815828d9440d5c9300d19547c from qemu
2018-03-20 10:42:20 -04:00