This finally paves the way for tcg/ to be built once per mode.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The bug was hidden because they happen to have the same values.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
qemu-user can hang in a multi-threaded fork. One common
reason is that when creating a TB, between fork and exec
we manipulate a GTree whose memory allocator (GSlice) is
not fork-safe.
Although POSIX does not mandate it, the system's allocator
(e.g. tcmalloc, libc malloc) is probably fork-safe.
Fix some of these hangs by using QTree, which uses the system's
allocator regardless of the Glib version that we used at
configuration time.
Tested with the test program in the original bug report, i.e.:
```
void garble() {
int pid = fork();
if (pid == 0) {
exit(0);
} else {
int wstatus;
waitpid(pid, &wstatus, 0);
}
}
void supragarble(unsigned depth) {
if (depth == 0)
return ;
std::thread a(supragarble, depth-1);
std::thread b(supragarble, depth-1);
garble();
a.join();
b.join();
}
int main() {
supragarble(10);
}
```
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/285
Reported-by: Valentin David <me@valentindavid.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Emilio Cota <cota@braap.org>
Message-Id: <20230205163758.416992-3-cota@braap.org>
[rth: Add QEMU_DISABLE_CFI for all callback using functions.]
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This fixes a bug in POSIX-compliant environments. Since we had allocated
a buffer named 'tcg-jit' with read-write access protections we need a int
type to combine these access flags and return it, whereas we had inexplicably
return a bool type. It may cause an unnecessary protection change in
tcg_region_init().
Cc: qemu-stable@nongnu.org
Fixes: 7be9ebcf92 ("tcg: Return the map protection from alloc_code_gen_buffer")
Signed-off-by: Shaobo Song <shnusongshaobo@gmail.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20220624150216.3627-1-shnusongshaobo@gmail.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Replace the global variables with inlined helper functions. getpagesize() is very
likely annotated with a "const" function attribute (at least with glibc), and thus
optimization should apply even better.
This avoids the need for a constructor initialization too.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20220323155743.1585078-12-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We can call do_tb_phys_invalidate from an iocontext, which has
no per-thread tcg_ctx. Move this to tb_ctx, which is global.
The actual update still takes place with a lock held, so only
an atomic set is required, not an atomic increment.
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/457
Tested-by: Viktor Ashirov <vashirov@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The function is called only at tcg_gen_code() when duplicated TBs
are translated by different threads, and when the tcg_region_tree
is reset. Bake it into the underlying GTree as its value destroy
function to unite these situations.
Also remove tcg_region_tree_traverse() which now becomes useless.
Signed-off-by: Liren Wei <lrwei@bupt.edu.cn>
Message-Id: <8dc352f08d038c4e7a1f5f56962398cdc700c3aa.1625404483.git.lrwei@bupt.edu.cn>
[rth: Name the new tb_tc_cmp parameter correctly.]
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Do not handle protections on a case-by-case basis in the
various alloc_code_gen_buffer instances; do it within a
single loop in tcg_region_init.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Luis Pires <luis.pires@eldorado.org.br>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
If qemu_get_host_physmem returns an odd number of pages,
then physmem / 8 will not be a multiple of the page size.
The following was observed on a gitlab runner:
ERROR qtest-arm/boot-serial-test - Bail out!
ERROR:../util/osdep.c:80:qemu_mprotect__osdep: \
assertion failed: (!(size & ~qemu_real_host_page_mask))
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Luis Pires <luis.pires@eldorado.org.br>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Change the interface from a boolean error indication to a
negative error vs a non-negative protection. For the moment
this is only interface change, not making use of the new data.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Luis Pires <luis.pires@eldorado.org.br>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Do not mess around with setting values within tcg_init_ctx.
Put the values into 'region' directly, which is where they
will live for the lifetime of the program.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Luis Pires <luis.pires@eldorado.org.br>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Shortly, the full code_gen_buffer will only be visible
to region.c, so move in_code_gen_buffer out-of-line.
Move the debugging versions of tcg_splitwx_to_{rx,rw}
to region.c as well, so that the compiler gets to see
the implementation of in_code_gen_buffer.
This leaves exactly one use of in_code_gen_buffer outside
of region.c, in cpu_restore_state. Which, being on the
exception path, is not performance critical.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Luis Pires <luis.pires@eldorado.org.br>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Compute the value using straight division and bounds,
rather than a loop. Pass in tb_size rather than reading
from tcg_init_ctx.code_gen_buffer_size,
Reviewed-by: Luis Pires <luis.pires@eldorado.org.br>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Start removing the include of hw/boards.h from tcg/.
Pass down the max_cpus value from tcg_init_machine,
where we have the MachineState already.
Reviewed-by: Luis Pires <luis.pires@eldorado.org.br>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Buffer management is integral to tcg. Do not leave the allocation
to code outside of tcg/. This is code movement, with further
cleanups to follow.
Reviewed-by: Luis Pires <luis.pires@eldorado.org.br>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>