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12 commits

Author SHA1 Message Date
Richard Henderson d7ea41c3a3
cpu: Move icount_decr to CPUNegativeOffsetState
Amusingly, we had already ignored the comment to keep this value
at the end of CPUState. This restores the minimum negative offset
from TCG_AREG0 for code generation.

For the couple of uses within qom/cpu.c, without NEED_CPU_H, add
a pointer from the CPUState object to the IcountDecr object within
CPUNegativeOffsetState.

Backports commit 5e1401969b25f676fee6b1c564441759cf967a43 from qemu
2019-06-13 15:34:28 -04:00
Richard Henderson 8fdd009a9d
tcg: Remove CF_IGNORE_ICOUNT
Now that we have curr_cflags, we can include CF_USE_ICOUNT
early and then remove it as necessary.

Backports commit 416986d3f97329655e30da7271a2d11c6d707b06 from qemu
2019-05-06 00:57:09 -04:00
Emilio G. Cota b1b069e8ad
cpu-exec: lookup/generate TB outside exclusive region during step_atomic
Now that all code generation has been converted to check CF_PARALLEL, we can
generate !CF_PARALLEL code without having yet set !parallel_cpus --
and therefore without having to be in the exclusive region during
cpu_exec_step_atomic.

While at it, merge cpu_exec_step into cpu_exec_step_atomic.

Backports commit ac03ee5331612e44beb393df2b578c951d27dc0d from qemu
2019-05-06 00:52:43 -04:00
Richard Henderson 30c0950567
tcg: Add CPUState cflags_next_tb
We were generating code during tb_invalidate_phys_page_range,
check_watchpoint, cpu_io_recompile, and (seemingly) discarding
the TB, assuming that it would magically be picked up during
the next iteration through the cpu_exec loop.

Instead, record the desired cflags in CPUState so that we request
the proper TB so that there is no more magic.

Backports commit 9b990ee5a3cc6aa38f81266fb0c6ef37a36c45b9 from qemu
2019-05-04 22:30:22 -04:00
Richard Henderson ee1ddf4a92
tcg: define CF_PARALLEL and use it for TB hashing along with CF_COUNT_MASK
This will enable us to decouple code translation from the value
of parallel_cpus at any given time. It will also help us minimize
TB flushes when generating code via EXCP_ATOMIC.

Note that the declaration of parallel_cpus is brought to exec-all.h
to be able to define there the "curr_cflags" inline.

Backports commit 4e2ca83e71b51577b06b1468e836556912bd5b6e from qemu
2019-05-04 22:22:06 -04:00
Lioncash 9dfe2b527b
cpu-exec: Synchronize with qemu 2019-04-26 16:07:51 -04:00
Lioncash d844d7cc9d
exec: Backport tb_cflags accessor 2019-04-22 06:12:59 -04:00
Thomas Huth 85bc48fecd
tcg: Fix LGPL version number
It's either "GNU *Library* General Public version 2" or "GNU Lesser
General Public version *2.1*", but there was no "version 2.0" of the
"Lesser" library. So assume that version 2.1 is meant here.

Backports commit fb0343d5b4dd4b9b9e96e563d913a3e0c709fe4e from qemu
2019-02-03 17:55:28 -05:00
Richard Henderson e01deeb9ba
tcg: Implement CPU_LOG_TB_NOCHAIN during expansion
Rather than test NOCHAIN before linking, do not emit the
goto_tb opcode at all. We already do this for goto_ptr.

Backports commit d7f425fdea991f052241c6479acd9feae834063b from qemu
2018-10-23 14:35:12 -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
Pavel Dovgalyuk 36d902cd0e
cpu-exec: fix exception_index handling
Function cpu_handle_interrupt calls cc->cpu_exec_interrupt to process
pending hardware interrupts. Under the hood cpu_exec_interrupt uses
cpu->exception_index to pass information to the internal function which
is usually common for exception and interrupt processing.
But this value is not reset after return and may be processed again
by cpu_handle_exception. This does not happen due to overwriting
the exception_index at the end of cpu_handle_interrupt.
But this branch may also overwrite the valid exception_index in some cases.
Therefore this patch:
1. resets exception_index just after the call to cpu_exec_interrupt
2. prevents overwriting the meaningful value of exception_index

Backports commit 5f3bdfd4fa33255542a4b6249913d9ffb11b44f9 from qemu
2018-03-17 19:33:05 -04:00
Lioncash 035f1afa7d
tcg: move tcg backend files into accel/tcg/
move tcg-runtime.c, translate-all.(ch) and translate-common.c into
accel/tcg/ subdirectory and updated related trace-events file.

Backports commit 244f144134d0dd182f1af8654e7f9a79fe770368 and applies
relevant changes made in db432672dc50ed86dda17ac821b7eb07411a90af and
d9bb58e51068dfc48746c6af0179926c8dc05bce from qemu
2018-03-13 11:48:15 -04:00
Renamed from qemu/cpu-exec.c (Browse further)