We try to avoid using cpu_loop_exit_atomic as it brings in an all-core
sync point. However on some cpu/kernel/benchmark combinations it is
starting to show up in the performance profile. To make it easier to
see whats going on add tracepoints for the slow path so we can see
what is triggering the wait.
It seems for a modern CPU it can be quite a bit, for example:
./qemu-system-aarch64 \
-machine type=virt,virtualization=on,pflash0=rom,pflash1=efivars,gic-version=max \
-smp 4 \
-accel tcg \
-device virtio-net-pci,netdev=unet \
-device virtio-scsi-pci \
-device scsi-hd,drive=hd \
-netdev user,id=unet,hostfwd=tcp::2222-:22 \
-blockdev driver=raw,node-name=hd,file.driver=host_device,file.filename=/dev/zen-ssd2/trixie-arm64,discard=unmap \
-serial mon:stdio \
-blockdev node-name=rom,driver=file,filename=(pwd)/pc-bios/edk2-aarch64-code.fd,read-only=true \
-blockdev node-name=efivars,driver=file,filename=$HOME/images/qemu-arm64-efivars \
-m 8192 \
-object memory-backend-memfd,id=mem,size=8G,share=on \
-kernel /home/alex/lsrc/linux.git/builds/arm64/arch/arm64/boot/Image -append "root=/dev/sda2 console=ttyAMA0 systemd.unit=benchmark-stress-ng.service" \
-display none -d trace:load_atom\*_fallback,trace:store_atom\*_fallback
With:
-cpu neoverse-v1,pauth-impdef=on => 2203343
With:
-cpu cortex-a76 => 0
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20241023113406.1284676-9-alex.bennee@linaro.org>
Rename to use "memop_" prefix, like other functions
that operate on MemOp.
Reviewed-by: Helge Deller <deller@gmx.de>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Commit e505a063ba ("translate-all: Add assert_(memory|tb)_lock
annotations") states page_set_flags() is "public APIs and [is]
documented as needing them held for linux-user mode".
Document the prototype.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20240822095045.72643-2-philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Use of these in helpers goes hand-in-hand with tlb_vaddr_to_host
and other probing functions.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20240428221450.26460-4-philmd@linaro.org>
Extract page-protection definitions from "exec/cpu-all.h"
to "exec/page-protection.h".
The list of files requiring the new header was generated
using:
$ git grep -wE \
'PAGE_(READ|WRITE|EXEC|RWX|VALID|ANON|RESERVED|TARGET_.|PASSTHROUGH)'
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Acked-by: Nicholas Piggin <npiggin@gmail.com>
Acked-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20240427155714.53669-3-philmd@linaro.org>
This macro can be used to abbreviate PAGE_READ | PAGE_WRITE | PAGE_EXEC
for which PAGE_RWX is a better name and renaming it also shows it is
not related to TARGET_PAGE_BITS.
Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20240505121008.44A0D4E602D@zero.eik.bme.hu>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
set_helper_retaddr() is only used in accel/tcg/user-exec.c.
clear_helper_retaddr() is only used in accel/tcg/cpu-exec.c
and accel/tcg/user-exec.c.
No need to expose their definitions to all user-emulation
files including "exec/cpu_ldst.h", move them to a new
"user-retaddr.h" header (restricted to accel/tcg/).
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20231211212003.21686-19-philmd@linaro.org>
Use qemu_real_host_page_size instead. Except for the final mprotect
within page_protect, we already handled host < target page size.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Ilya Leoshkevich <iii@linux.ibm.com>
Acked-by: Helge Deller <deller@gmx.de>
Message-Id: <20240102015808.132373-2-richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20231004090629.37473-6-philmd@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
cpu_in_serial_context() is not target specific,
move it declaration to "internal-common.h" (which
we include in the 4 source files modified).
Remove the unused "exec/exec-all.h" header from
cpu-exec-common.c. There is no more target specific
code in this file: make it target agnostic.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Anton Johansson <anjo@rev.ng>
Message-Id: <20230914185718.76241-12-philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
accel/tcg/internal.h contains target specific declarations.
Unit files including it become "target tainted": they can not
be compiled as target agnostic. Rename using the '-target'
suffix to make this explicit.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Anton Johansson <anjo@rev.ng>
Message-Id: <20230914185718.76241-9-philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
A large chunk of ld/st functions are moved from cputlb.c and user-exec.c
to ldst_common.c.inc as their implementation is the same between both
modes.
Eventually, ldst_common.c.inc could be compiled into a separate
target-specific compilation unit, and be linked in with the targets.
Keeping CPUArchState usage out of cputlb.c (CPUArchState is primarily
used to access the mmu index in these functions).
Signed-off-by: Anton Johansson <anjo@rev.ng>
Message-Id: <20230912153428.17816-12-anjo@rev.ng>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The prototype of do_[st|ld]*_mmu() is unified between system- and
user-mode allowing a large chunk of helper_[st|ld]*() and cpu_[st|ld]*()
functions to be expressed in same manner between both modes. These
functions will be moved to ldst_common.c.inc in a following commit.
Signed-off-by: Anton Johansson <anjo@rev.ng>
Message-Id: <20230912153428.17816-11-anjo@rev.ng>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Makes ldst_atomicity.c.inc almost target-independent, with the exception
of TARGET_PAGE_MASK, which will be addressed in a future patch.
Signed-off-by: Anton Johansson <anjo@rev.ng>
Message-Id: <20230912153428.17816-8-anjo@rev.ng>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The goal is to (in the future) allow for per-target compilation of
functions in atomic_template.h whilst atomic_mmu_lookup() and cputlb.c
are compiled once-per user- or system mode.
Signed-off-by: Anton Johansson <anjo@rev.ng>
Message-Id: <20230912153428.17816-7-anjo@rev.ng>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
[rth: Use cpu->neg.tlb instead of cpu_tlb()]
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
These should match 'start' as target_ulong, not target_long.
On 32bit targets, the parameter was sign-extended to uint64_t,
so only the first mmap within the upper 2GB memory can succeed.
Signed-off-by: Luca Bonissi <qemu@bonslack.org>
Message-Id: <327460e2-0ebd-9edb-426b-1df80d16c32a@bonslack.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
We adjust CONFIG_ATOMIC128 and CONFIG_CMPXCHG128 with
CONFIG_ATOMIC128_OPT in atomic128.h. It is difficult
to tell when those changes have been applied with the
ifdef we must use with CONFIG_CMPXCHG128. So instead
use HAVE_CMPXCHG128, which triggers -Werror-undef when
the proper header has not been included.
Improves tcg_gen_atomic_cmpxchg_i128 for s390x host, which
requires CONFIG_ATOMIC128_OPT. Without this we fall back
to EXCP_ATOMIC to single-step 128-bit atomics, which is
slow enough to cause some tests to time out.
Reported-by: Thomas Huth <thuth@redhat.com>
Tested-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Replace the 0/-1 result with true/false.
Invert the sense of the test of all callers.
Document the function.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230707204054.8792-25-richard.henderson@linaro.org>
Only PAGE_WRITE needs special attention, all others can be
handled as we do for PAGE_READ. Adjust the mask.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230707204054.8792-24-richard.henderson@linaro.org>
Use the interval tree to locate an unused range in the VM.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230707204054.8792-17-richard.henderson@linaro.org>
Examine the interval tree to validate that a region
has no existing mappings.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230707204054.8792-10-richard.henderson@linaro.org>
The lack of SVE memory instrumentation has been an omission in plugin
handling since it was introduced. Fortunately we can utilise the
probe_* functions to force all all memory access to follow the slow
path. We do this by checking the access type and presence of plugin
memory callbacks and if set return the TLB_MMIO flag.
We have to jump through a few hoops in user mode to re-use the flag
but it was the desired effect:
./qemu-system-aarch64 -display none -serial mon:stdio \
-M virt -cpu max -semihosting-config enable=on \
-kernel ./tests/tcg/aarch64-softmmu/memory-sve \
-plugin ./contrib/plugins/libexeclog.so,ifilter=st1w,afilter=0x40001808 -d plugin
gives (disas doesn't currently understand st1w):
0, 0x40001808, 0xe54342a0, ".byte 0xa0, 0x42, 0x43, 0xe5", store, 0x40213010, RAM, store, 0x40213014, RAM, store, 0x40213018, RAM
And for user-mode:
./qemu-aarch64 \
-plugin contrib/plugins/libexeclog.so,afilter=0x4007c0 \
-d plugin \
./tests/tcg/aarch64-linux-user/sha512-sve
gives:
1..10
ok 1 - do_test(&tests[i])
0, 0x4007c0, 0xa4004b80, ".byte 0x80, 0x4b, 0x00, 0xa4", load, 0x5500800370, load, 0x5500800371, load, 0x5500800372, load, 0x5500800373, load, 0x5500800374, load, 0x5500800375, load, 0x5500800376, load, 0x5500800377, load, 0x5500800378, load, 0x5500800379, load, 0x550080037a, load, 0x550080037b, load, 0x550080037c, load, 0x550080037d, load, 0x550080037e, load, 0x550080037f, load, 0x5500800380, load, 0x5500800381, load, 0x5500800382, load, 0x5500800383, load, 0x5500800384, load, 0x5500800385, load, 0x5500800386, lo
ad, 0x5500800387, load, 0x5500800388, load, 0x5500800389, load, 0x550080038a, load, 0x550080038b, load, 0x550080038c, load, 0x550080038d, load, 0x550080038e, load, 0x550080038f, load, 0x5500800390, load, 0x5500800391, load, 0x5500800392, load, 0x5500800393, load, 0x5500800394, load, 0x5500800395, load, 0x5500800396, load, 0x5500800397, load, 0x5500800398, load, 0x5500800399, load, 0x550080039a, load, 0x550080039b, load, 0x550080039c, load, 0x550080039d, load, 0x550080039e, load, 0x550080039f, load, 0x55008003a0, load, 0x55008003a1, load, 0x55008003a2, load, 0x55008003a3, load, 0x55008003a4, load, 0x55008003a5, load, 0x55008003a6, load, 0x55008003a7, load, 0x55008003a8, load, 0x55008003a9, load, 0x55008003aa, load, 0x55008003ab, load, 0x55008003ac, load, 0x55008003ad, load, 0x55008003ae, load, 0x55008003af
(4007c0 is the ld1b in the sha512-sve)
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Cc: Robert Henry <robhenry@microsoft.com>
Cc: Aaron Lindsay <aaron@os.amperecomputing.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230630180423.558337-20-alex.bennee@linaro.org>
Bring the helpers into line with the rest of tcg in respecting
guest memory ordering.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Update atomic_mmu_lookup() and cpu_mmu_lookup() to take the guest
virtual address as a vaddr instead of a target_ulong.
Signed-off-by: Anton Johansson <anjo@rev.ng>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230621135633.1649-10-anjo@rev.ng>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Functions for probing memory accesses (and functions that call these)
are updated to take a vaddr for guest virtual addresses over
target_ulong.
Signed-off-by: Anton Johansson <anjo@rev.ng>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230621135633.1649-9-anjo@rev.ng>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
These symbols will shortly become dynamic runtime tests and
therefore not appropriate for the preprocessor. Use the
matching CONFIG_* symbols for that purpose.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Now that load/store are gone, we're always passing
PAGE_READ | PAGE_WRITE for RMW atomic operations.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
With the current structure of cputlb.c, there is no difference
between the little-endian and big-endian entry points, aside
from the assert. Unify the pairs of functions.
The only use of the functions with explicit endianness was in
target/sparc64, and that was only to satisfy the assert: the
correct endianness is already built into memop.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Always pass the target address as uint64_t.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Always pass the target address as uint64_t.
Adjust tcg_out_{ld,st}_helper_args to match.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
TCG backends may need to defer to a helper to implement
the atomicity required by a given operation. Mirror the
interface used in system mode.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Create ldst_atomicity.c.inc.
Not required for user-only code loads, because we've ensured that
the page is read-only before beginning to translate code.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
At least RISC-V has the need to be able to perform a read
using execute permissions, outside of translation.
Add helpers to facilitate this.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Weiwei Li <liweiwei@iscas.ac.cn>
Tested-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Message-Id: <20230325105429.1142530-9-richard.henderson@linaro.org>
Message-Id: <20230412114333.118895-9-richard.henderson@linaro.org>
Pass the address of the last byte to be changed, rather than
the first address past the last byte. This avoids overflow
when the last page of the address space is involved.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Pass the address of the last byte to be changed, rather than
the first address past the last byte. This avoids overflow
when the last page of the address space is involved.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Pass the address of the last byte to be changed, rather than
the first address past the last byte. This avoids overflow
when the last page of the address space is involved.
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1528
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
probe_access_flags() as it is today uses probe_access_full(), which in
turn uses probe_access_internal() with size = 0. probe_access_internal()
then uses the size to call the tlb_fill() callback for the given CPU.
This size param ('fault_size' as probe_access_internal() calls it) is
ignored by most existing .tlb_fill callback implementations, e.g.
arm_cpu_tlb_fill(), ppc_cpu_tlb_fill(), x86_cpu_tlb_fill() and
mips_cpu_tlb_fill() to name a few.
But RISC-V riscv_cpu_tlb_fill() actually uses it. The 'size' parameter
is used to check for PMP (Physical Memory Protection) access. This is
necessary because PMP does not make any guarantees about all the bytes
of the same page having the same permissions, i.e. the same page can
have different PMP properties, so we're forced to make sub-page range
checks. To allow RISC-V emulation to do a probe_acess_flags() that
covers PMP, we need to either add a 'size' param to the existing
probe_acess_flags() or create a new interface (e.g.
probe_access_range_flags).
There are quite a few probe_* APIs already, so let's add a 'size' param
to probe_access_flags() and re-use this API. This is done by open coding
what probe_access_full() does inside probe_acess_flags() and passing the
'size' param to probe_acess_internal(). Existing probe_access_flags()
callers use size = 0 to not change their current API usage. 'size' is
asserted to enforce single page access like probe_access() already does.
No behavioral changes intended.
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Message-Id: <20230223234427.521114-2-dbarboza@ventanamicro.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
These are not yet considering atomicity of the 16-byte value;
this is a direct replacement for the current target code which
uses a pair of 8-byte operations.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
As in page_get_flags, we need to try again with the mmap
lock held if we fail a page lookup.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Because we allow lockless lookups, we have to be careful
when it is freed. Use rcu to delay the free until safe.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This page tracking implementation is specific to user-only,
since the system softmmu version is in cputlb.c. Move it
out of translate-all.c to user-exec.c.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Continue weaning user-only away from PageDesc.
Use an interval tree to record target data.
Chunk the data, to minimize allocation overhead.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Since the only user, Arm MTE, always requires allocation,
merge the get and alloc functions to always produce a
non-null result. Also assume that the user has already
checked page validity.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Since "target data" is always user-only, move it out of
translate-all.c to user-exec.c.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>