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authorAlex Bennée <alex.bennee@linaro.org>2022-02-04 20:43:26 +0000
committerAlex Bennée <alex.bennee@linaro.org>2022-02-09 12:08:42 +0000
commitd9a6bad542cd796c785ff19793fa7ae24da6a97d (patch)
treedf014b16e60c89eb608725817f546307e44e138a /docs/devel/tracing.rst
parent3bdc19af00937191623fb0a2cacbc4ad54882072 (diff)
docs: remove references to TCG tracing
Users wanting this sort of functionality should turn to TCG plugins instead. Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Cc: Luis Vilanova <vilanova@imperial.ac.uk> Cc: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20220204204335.1689602-18-alex.bennee@linaro.org>
Diffstat (limited to 'docs/devel/tracing.rst')
-rw-r--r--docs/devel/tracing.rst85
1 files changed, 0 insertions, 85 deletions
diff --git a/docs/devel/tracing.rst b/docs/devel/tracing.rst
index 4290ac42ee..ec9a687cfd 100644
--- a/docs/devel/tracing.rst
+++ b/docs/devel/tracing.rst
@@ -413,88 +413,3 @@ disabled, this check will have no performance impact.
return ptr;
}
-"tcg"
------
-
-Guest code generated by TCG can be traced by defining an event with the "tcg"
-event property. Internally, this property generates two events:
-"<eventname>_trans" to trace the event at translation time, and
-"<eventname>_exec" to trace the event at execution time.
-
-Instead of using these two events, you should instead use the function
-"trace_<eventname>_tcg" during translation (TCG code generation). This function
-will automatically call "trace_<eventname>_trans", and will generate the
-necessary TCG code to call "trace_<eventname>_exec" during guest code execution.
-
-Events with the "tcg" property can be declared in the "trace-events" file with a
-mix of native and TCG types, and "trace_<eventname>_tcg" will gracefully forward
-them to the "<eventname>_trans" and "<eventname>_exec" events. Since TCG values
-are not known at translation time, these are ignored by the "<eventname>_trans"
-event. Because of this, the entry in the "trace-events" file needs two printing
-formats (separated by a comma)::
-
- tcg foo(uint8_t a1, TCGv_i32 a2) "a1=%d", "a1=%d a2=%d"
-
-For example::
-
- #include "trace-tcg.h"
-
- void some_disassembly_func (...)
- {
- uint8_t a1 = ...;
- TCGv_i32 a2 = ...;
- trace_foo_tcg(a1, a2);
- }
-
-This will immediately call::
-
- void trace_foo_trans(uint8_t a1);
-
-and will generate the TCG code to call::
-
- void trace_foo(uint8_t a1, uint32_t a2);
-
-"vcpu"
-------
-
-Identifies events that trace vCPU-specific information. It implicitly adds a
-"CPUState*" argument, and extends the tracing print format to show the vCPU
-information. If used together with the "tcg" property, it adds a second
-"TCGv_env" argument that must point to the per-target global TCG register that
-points to the vCPU when guest code is executed (usually the "cpu_env" variable).
-
-The "tcg" and "vcpu" properties are currently only honored in the root
-./trace-events file.
-
-The following example events::
-
- foo(uint32_t a) "a=%x"
- vcpu bar(uint32_t a) "a=%x"
- tcg vcpu baz(uint32_t a) "a=%x", "a=%x"
-
-Can be used as::
-
- #include "trace-tcg.h"
-
- CPUArchState *env;
- TCGv_ptr cpu_env;
-
- void some_disassembly_func(...)
- {
- /* trace emitted at this point */
- trace_foo(0xd1);
- /* trace emitted at this point */
- trace_bar(env_cpu(env), 0xd2);
- /* trace emitted at this point (env) and when guest code is executed (cpu_env) */
- trace_baz_tcg(env_cpu(env), cpu_env, 0xd3);
- }
-
-If the translating vCPU has address 0xc1 and code is later executed by vCPU
-0xc2, this would be an example output::
-
- // at guest code translation
- foo a=0xd1
- bar cpu=0xc1 a=0xd2
- baz_trans cpu=0xc1 a=0xd3
- // at guest code execution
- baz_exec cpu=0xc2 a=0xd3