CPU watchpoints can be use by non-TCG accelerators.
KVM uses them:
$ git grep CPUWatchpoint|fgrep kvm
target/arm/kvm64.c:1558: CPUWatchpoint *wp = find_hw_watchpoint(cs, debug_exit->far);
target/i386/kvm/kvm.c:5216:static CPUWatchpoint hw_watchpoint;
target/ppc/kvm.c:443:static CPUWatchpoint hw_watchpoint;
target/s390x/kvm/kvm.c:139:static CPUWatchpoint hw_watchpoint;
See for example commit e4482ab7e3 ("target-arm: kvm - add support
for HW assisted debug"):
This adds basic support for HW assisted debug. The ioctl interface
to KVM allows us to pass an implementation defined number of break
and watch point registers. [...]
This partially reverts commit 2609ec2868.
Fixes: 2609ec2868 ("softmmu: Extract watchpoint API from physmem.c")
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230328173117.15226-4-philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
cpu_watchpoint_insert() calls error_report() which is declared
in "qemu/error-report.h". When moving this code in commit 2609ec2868
("softmmu: Extract watchpoint API from physmem.c") we neglected to
include this header. This works so far because it is indirectly
included by TCG headers -> "qemu/plugin.h" -> "qemu/error-report.h".
Currently cpu_watchpoint_insert() is only built with the TCG
accelerator. When building it with other ones (or without TCG)
we get:
softmmu/watchpoint.c:38:9: error: implicit declaration of function 'error_report' is invalid in C99 [-Werror,-Wimplicit-function-declaration]
error_report("tried to set invalid watchpoint at %"
^
Include "qemu/error-report.h" in order to fix this for non-TCG
builds.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230328173117.15226-3-philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Atomic operations are read-modify-write, and we'd like to
be able to test both read and write with one call. This is
easy enough, with BP_MEM_READ | BP_MEM_WRITE.
Add BP_HIT_SHIFT to make it easy to set BP_WATCHPOINT_HIT_*.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The watchpoint API is specific to TCG system emulation.
Move it to a new compile unit. The inlined stubs are used
for user-mode and non-TCG accelerators.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20221209141254.68662-1-philmd@linaro.org>