On 11/4/24 18:29, Demin Han wrote:
-----Original Message-----
From: Pierrick Bouvier <pierrick.bouv...@linaro.org>
Sent: 2024年11月5日 5:22
To: Demin Han <demin....@starfivetech.com>; qemu-devel@nongnu.org
Cc: alex.ben...@linaro.org; erdn...@crans.org; ma.mando...@gmail.com
Subject: Re: [PATCH] plugins: add plugin API to get args passed to binary
On 11/1/24 22:10, Demin Han wrote:
Hi,
Many benchmarks have their own build and run system, such as specint,
we don’t want to change their code.
I don't think those benchmarks (such as specint) integrate calling qemu with a
specific plugin on command line, so I guess you have a wrapper or something
where you could pass necessary information, or tweak output file, without
changing the benchmark itself. In case I'm wrong, feel free to correct me.
I have two methods without change test code, but they can't get args passed to
binary:
1. for those without hook, such as specint, we can utilize binfmt_misc.
We may need a simple wrapper just to load plugin or set some common options
and register this wrapper to binfmt_misc
2. for those with hook, such as llvm-test-suite, we can set
TEST_SUITE_RUN_UNDER or utilize binfmt_misc
I have no idea to write a wrapper which can get args passed to binary without
change code.
If have, please give a example or some hint.
If you use binfmt_misc, how are you passing the argument to use a plugin?
In the case of llvm-test-suite, you can set TEST_SUITE_RUN_UNDER to a
wrapper adding a specific plugin, its options, and generating the log
filename as expected.
Actually the log maybe structural data such as in json format and may
be output multiple log files with different statistics dimention for one run.
-D can’t satisfy this.
Indeed, it can output only a single file. If your plugin needs something more
advanced, you can try to output something yourself. However, a better and
simpler way would be to prefix lines output with a specific marker, and post
process your plugin trace with a custom script.
Adding command line access to plugins does not solve any of those problems.
I see value in what this series offer, but I don't see how it's related to the
current need you express.
Yes, this is not important and not most concerned.
But if we can directly output json or yaml, it would be convenient for
post-processing.
This is a bonus for this added api.
It's something you can do directly in the plugin, by outputing
json/yaml, or any format wanted. It's probably not a feature we'll
provide in the public API as it's a very specific need.
Regards,
Demin
Regards,
Pierrick
Regard,
Denin
获取 Outlook for iOS <https://aka.ms/o0ukef>
----------------------------------------------------------------------
--
*发件人:* Pierrick Bouvier <pierrick.bouv...@linaro.org>
*发送时间:* Saturday, November 2, 2024 2:18:20 AM
*收件人:* Demin Han <demin....@starfivetech.com>;
qemu-devel@nongnu.org
<qemu-devel@nongnu.org>
*抄送:* alex.ben...@linaro.org <alex.ben...@linaro.org>;
erdn...@crans.org <erdn...@crans.org>; ma.mando...@gmail.com
<ma.mando...@gmail.com>
*主题:* Re: [PATCH] plugins: add plugin API to get args passed to binary
Hi Demin,
thanks for your contribution.
On 11/1/24 02:00, demin.han wrote:
Why we need args?
When plugin outputs log files, only binary path can't distinguish
multiple runs if the binary passed with different args.
This is bad for CI using plugin.
Can it be solved simply by encoding this in name of log file from the
CI run script?
$ cmd="/usr/bin/echo Hello world"
$ out_file="$(echo "$cmd" | sed -e 's/\s/_/').log"
$ qemu -plugin... -d plugin -D "$out_file" $cmd
I can see some good points to add this new API, but for the use case
presented in commit message, I'm not sure to see what it solves.
Signed-off-by: demin.han <demin....@starfivetech.com>
---
include/qemu/qemu-plugin.h | 11 +++++++++++
plugins/api.c | 16 ++++++++++++++++
plugins/qemu-plugins.symbols | 1 +
3 files changed, 28 insertions(+)
diff --git a/include/qemu/qemu-plugin.h b/include/qemu/qemu-plugin.h
index 622c9a0232..daf75c9f5a 100644
--- a/include/qemu/qemu-plugin.h
+++ b/include/qemu/qemu-plugin.h
@@ -837,6 +837,17 @@ bool qemu_plugin_bool_parse(const char *name,
const char *val, bool *ret);
QEMU_PLUGIN_API
const char *qemu_plugin_path_to_binary(void);
+/**
+ * qemu_plugin_argv_to_binary() - argv to binary file being executed
+ *
+ * Return a string array representing the argv to the binary. For
+user-mode
+ * this is the main executable's argv. For system emulation we
+currently
+ * return NULL. The user should g_free() the string array once no
+longer
+ * needed.
+ */
+QEMU_PLUGIN_API
+const char **qemu_plugin_argv_to_binary(void);
+
/**
* qemu_plugin_start_code() - returns start of text segment
*
diff --git a/plugins/api.c b/plugins/api.c index
24ea64e2de..fa2735db03 100644
--- a/plugins/api.c
+++ b/plugins/api.c
@@ -485,6 +485,22 @@ const char *qemu_plugin_path_to_binary(void)
return path;
}
+const char **qemu_plugin_argv_to_binary(void)
+{
+ const char **argv = NULL;
+#ifdef CONFIG_USER_ONLY
+ int i, argc;
+ TaskState *ts = get_task_state(current_cpu);
+ argc = ts->bprm->argc;
+ argv = g_malloc(sizeof(char *) * (argc + 1));
+ for (i = 0; i < argc; ++i) {
+ argv[i] = g_strdup(ts->bprm->argv[i]);
+ }
+ argv[argc] = NULL;
+#endif
+ return argv;
+}
+
uint64_t qemu_plugin_start_code(void)
{
uint64_t start = 0;
diff --git a/plugins/qemu-plugins.symbols
b/plugins/qemu-plugins.symbols index 032661f9ea..532582effe 100644
--- a/plugins/qemu-plugins.symbols
+++ b/plugins/qemu-plugins.symbols
@@ -1,4 +1,5 @@
{
+ qemu_plugin_argv_to_binary;
qemu_plugin_bool_parse;
qemu_plugin_end_code;
qemu_plugin_entry_code;
Regards,
Pierrick
