Commit Graph

33 Commits

Author SHA1 Message Date
Pierrick Bouvier
b709da5d29 plugins: save value during memory accesses
Different code paths handle memory accesses:
- tcg generated code
- load/store helpers
- atomic helpers

This value is saved in cpu->neg.plugin_mem_value_{high,low}. Values are
written only for accessed word size (upper bits are not set).

Atomic operations are doing read/write at the same time, so we generate
two memory callbacks instead of one, to allow plugins to access distinct
values.

For now, we can have access only up to 128 bits, thus split this in two
64 bits words. When QEMU will support wider operations, we'll be able to
reconsider this.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Message-Id: <20240724194708.1843704-2-pierrick.bouvier@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240916085400.1046925-5-alex.bennee@linaro.org>
2024-09-19 15:58:01 +01:00
Anton Johansson
d560225fc4 accel/tcg: Modify atomic_mmu_lookup() to use CPUState
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>
2023-10-04 11:03:54 -07:00
Anton Johansson
022b9bcede include/exec: Replace target_ulong with abi_ptr in cpu_[st|ld]*()
Changes the address type of the guest memory read/write functions from
target_ulong to abi_ptr. (abi_ptr is currently typedef'd to target_ulong
but that will change in a following commit.) This will reduce the
coupling between accel/ and target/.

Note: Function pointers that point to cpu_[st|ld]*() in target/riscv and
target/rx are also updated in this commit.

Signed-off-by: Anton Johansson <anjo@rev.ng>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230807155706.9580-6-anjo@rev.ng>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-08-24 11:21:46 -07:00
Richard Henderson
7bedee3243 accel/tcg: Remove prot argument to atomic_mmu_lookup
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>
2023-05-23 18:54:55 -07:00
Richard Henderson
ec4a9629a1 accel/tcg: Remove cpu_atomic_{ld,st}o_*_mmu
Atomic load/store of 128-byte quantities is now handled
by cpu_{ld,st}16_mmu.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-05-23 18:54:55 -07:00
Marc-André Lureau
e03b56863d Replace config-time define HOST_WORDS_BIGENDIAN
Replace a config-time define with a compile time condition
define (compatible with clang and gcc) that must be declared prior to
its usage. This avoids having a global configure time define, but also
prevents from bad usage, if the config header wasn't included before.

This can help to make some code independent from qemu too.

gcc supports __BYTE_ORDER__ from about 4.6 and clang from 3.2.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
[ For the s390x parts I'm involved in ]
Acked-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220323155743.1585078-7-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-04-06 10:50:37 +02:00
Alex Bennée
c51e51005b tracing: remove TCG memory access tracing
If you really want to trace all memory operations TCG plugins gives
you a more flexible interface for doing so.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Cc: Luis Vilanova <vilanova@imperial.ac.uk>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20220204204335.1689602-19-alex.bennee@linaro.org>
2022-02-09 12:08:42 +00:00
Richard Henderson
0583f775d2 trace: Split guest_mem_before
There is no point in encoding load/store within a bit of
the memory trace info operand.  Represent atomic operations
as a single read-modify-write tracepoint.  Use MemOpIdx
instead of inventing a form specifically for traces.

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-10-05 16:53:17 -07:00
Richard Henderson
c3e83e376c accel/tcg: Pass MemOpIdx to atomic_trace_*_post
We will shortly use the MemOpIdx directly, but in the meantime
re-compute the trace meminfo.

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-10-05 16:53:17 -07:00
Richard Henderson
9002ffcb72 tcg: Rename TCGMemOpIdx to MemOpIdx
We're about to move this out of tcg.h, so rename it
as we did when moving MemOp.

Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-10-05 16:53:17 -07:00
Richard Henderson
7039e1f604 accel/tcg: Remove double bswap for helper_atomic_sto_*_mmu
This crept in as either a cut-and-paste error, or rebase error.

Fixes: cfec388518 ("atomic_template: add inline trace/plugin helpers")
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20210729004647.282017-24-richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-07-30 08:23:12 -10:00
Richard Henderson
f3e182b100 accel/tcg: Push trace info building into atomic_common.c.inc
Use trace_mem_get_info instead of trace_mem_build_info,
using the TCGMemOpIdx that we already have.  Do this in
the atomic_trace_*_pre function as common subroutines.

Tested-by: Cole Robinson <crobinso@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-07-21 07:45:38 -10:00
Richard Henderson
a754f7f34e accel/tcg: Expand ATOMIC_MMU_LOOKUP_*
Unify the parameters of atomic_mmu_lookup between cputlb.c and
user-exec.c.  Call the function directly, and remove the macros.

Tested-by: Cole Robinson <crobinso@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-07-21 07:45:38 -10:00
Richard Henderson
fcff001441 accel/tcg: Remove ATOMIC_MMU_DECLS
All definitions are now empty.

Tested-by: Cole Robinson <crobinso@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-07-21 07:45:38 -10:00
Richard Henderson
48688fafeb accel/tcg: Fold EXTRA_ARGS into atomic_template.h
All instances of EXTRA_ARGS are now identical.

Tested-by: Cole Robinson <crobinso@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-07-21 07:45:38 -10:00
Richard Henderson
9ef0c6d6a7 qemu/atomic: Add aligned_{int64,uint64}_t types
Use it to avoid some clang-12 -Watomic-alignment errors,
forcing some structures to be aligned and as a pointer when
we have ensured that the address is aligned.

Tested-by: Cole Robinson <crobinso@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-07-21 07:45:38 -10:00
Richard Henderson
08dff435e2 accel/tcg: Probe the proper permissions for atomic ops
We had a single ATOMIC_MMU_LOOKUP macro that probed for
read+write on all atomic ops.  This is incorrect for
plain atomic load and atomic store.

For user-only, we rely on the host page permissions.

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/390
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-06-19 11:09:10 -07:00
Stefan Hajnoczi
d73415a315 qemu/atomic.h: rename atomic_ to qatomic_
clang's C11 atomic_fetch_*() functions only take a C11 atomic type
pointer argument. QEMU uses direct types (int, etc) and this causes a
compiler error when a QEMU code calls these functions in a source file
that also included <stdatomic.h> via a system header file:

  $ CC=clang CXX=clang++ ./configure ... && make
  ../util/async.c:79:17: error: address argument to atomic operation must be a pointer to _Atomic type ('unsigned int *' invalid)

Avoid using atomic_*() names in QEMU's atomic.h since that namespace is
used by <stdatomic.h>. Prefix QEMU's APIs with 'q' so that atomic.h
and <stdatomic.h> can co-exist. I checked /usr/include on my machine and
searched GitHub for existing "qatomic_" users but there seem to be none.

This patch was generated using:

  $ git grep -h -o '\<atomic\(64\)\?_[a-z0-9_]\+' include/qemu/atomic.h | \
    sort -u >/tmp/changed_identifiers
  $ for identifier in $(</tmp/changed_identifiers); do
        sed -i "s%\<$identifier\>%q$identifier%g" \
            $(git grep -I -l "\<$identifier\>")
    done

I manually fixed line-wrap issues and misaligned rST tables.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200923105646.47864-1-stefanha@redhat.com>
2020-09-23 16:07:44 +01:00
Richard Henderson
4e6b138495 trace: Remove trace_mem_build_info_no_se_[bl]e
It is easy for the atomic helpers to use trace_mem_build_info
directly, without resorting to symbol pasting.  For this usage,
we cannot use trace_mem_get_info, because the MemOp does not
support 16-byte accesses.

Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2020-01-15 15:13:09 -10:00
Emilio G. Cota
e6d86bed50 tcg: let plugins instrument virtual memory accesses
To capture all memory accesses we need hook into all the various
helper functions that are involved in memory operations as well as the
injected inline helper calls. A later commit will allow us to resolve
the actual guest HW addresses by replaying the lookup.

Signed-off-by: Emilio G. Cota <cota@braap.org>
[AJB: drop haddr handling, just deal in vaddr]
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2019-10-28 15:12:38 +00:00
Emilio G. Cota
cfec388518 atomic_template: add inline trace/plugin helpers
In preparation for plugin support.

Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2019-10-28 15:12:38 +00:00
Alex Bennée
504f73f7b3 trace: add mmu_index to mem_info
We are going to re-use mem_info later for plugins and will need to
track the mmu_idx for softmmu code.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
2019-10-28 15:12:38 +00:00
Emilio G. Cota
d2fac5f678 atomic_template: fix indentation in GEN_ATOMIC_HELPER
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2019-09-13 16:05:01 +01:00
Emilio G. Cota
358f6348df atomic_template: fix indentation in GEN_ATOMIC_HELPER
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20190828165307.18321-8-alex.bennee@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2019-09-03 16:20:35 +01:00
Richard Henderson
29a0af618d cpu: Replace ENV_GET_CPU with env_cpu
Now that we have both ArchCPU and CPUArchState, we can define
this generically instead of via macro in each target's cpu.h.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2019-06-10 07:03:34 -07:00
Thomas Huth
fb0343d5b4 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.

Cc: Richard Henderson <rth@twiddle.net>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <1548252536-6242-5-git-send-email-thuth@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2019-01-30 11:01:52 +01:00
Richard Henderson
e6cd4bb59b 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.

Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2018-10-18 19:46:36 -07:00
Emilio G. Cota
d071f4cd55 trace: enable tracing of TCG atomics
We do not trace guest atomic accesses. Fix it.

Tested with a modified atomic_add-bench so that it executes
a deterministic number of instructions, i.e. fixed seeding,
no threading and fixed number of loop iterations instead
of running for a certain time.

Before:
- With parallel_cpus = false (no clone syscall so it is never set to true):
  220070 memory accesses
- With parallel_cpus = true (hard-coded):
  212105 memory accesses <-- we're not tracing the atomics!

After:
  220070 memory accesses regardless of parallel_cpus.

Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-id: 1527028012-21888-6-git-send-email-cota@braap.org
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2018-06-27 11:09:24 +01:00
Richard Henderson
58edf9eef9 tcg: Use GEN_ATOMIC_HELPER_FN for opposite endian atomic add
Suggested-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180508151437.4232-6-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-05-10 18:10:57 +01:00
Richard Henderson
5507c2bf35 tcg: Introduce atomic helpers for integer min/max
Given that this atomic operation will be used by both risc-v
and aarch64, let's not duplicate code across the two targets.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180508151437.4232-5-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-05-10 18:10:57 +01:00
Peter Maydell
34d49937e4 accel/tcg: Handle atomic accesses to notdirty memory correctly
To do a write to memory that is marked as notdirty, we need
to invalidate any TBs we have cached for that memory, and
update the cpu physical memory dirty flags for VGA and migration.
The slowpath code in notdirty_mem_write() does all this correctly,
but the new atomic handling code in atomic_mmu_lookup() doesn't
do anything at all, it just clears the dirty bit in the TLB.

The effect of this bug is that if the first write to a notdirty
page for which we have cached TBs is by a guest atomic access,
we fail to invalidate the TBs and subsequently will execute
incorrect code. This can be seen by trying to run 'javac' on AArch64.

Use the new notdirty_call_before() and notdirty_call_after()
functions to correctly handle the update to notdirty memory
in the atomic codepath.

Cc: qemu-stable@nongnu.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1511201308-23580-3-git-send-email-peter.maydell@linaro.org
2017-11-21 12:09:25 +00:00
Richard Henderson
ec603b5584 tcg: Record code_gen_buffer address for user-only memory helpers
When we handle a signal from a fault within a user-only memory helper,
we cannot cpu_restore_state with the PC found within the signal frame.
Use a TLS variable, helper_retaddr, to record the unwind start point
to find the faulting guest insn.

Tested-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reported-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-11-15 10:33:27 +01:00
Philippe Mathieu-Daudé
10f7d4d53d accel/tcg: move atomic_template.h to accel/tcg/
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Tested-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20170911213328.9701-5-f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2017-09-17 06:52:19 -07:00