update readme

1 files changed, 193 insertions, 93 deletions

diff --git a/README.md b/README.md
index 409f05b..c71deda 100644
--- a/README.md
+++ b/README.md
@@ -1,76 +1,83 @@
 ## Variable Monitor
 
-Monitor numerical variables (given address, length), and print system stack information when the set conditions are exceeded.
+changelog
 
-Number of simultaneous monitoring
-- Monitoring with the same timing length will be grouped into one group, corresponding to one timer.
-- A set of up to 32 variables, after which a new timer is allocated.
-- The global maximum number of timers is 128.
-- The above quantity limit is defined in the `watch_module.h` header macro.
-
-Currently, monitoring is limited to the same application, and simultaneous calls from multiple applications are not currently supported.
-- Multiple applications can work normally if only one program calls `cancel_all_watch();`.
+```log
+11.9  多个变量监控支持
+11.10 按照 pid 区分不同内核结构, 支持每个进程单独申请取消自己的监控.
+11.13 用户接口 cancel_all_watch -> cancel_watch, 每个进程互不干扰.
+11.28 完全重构,更新文档.
+```
 
-## Usage
+## 说明
 
-Example: helloworld.c
-- Add `#include "watch.h"`
-- Set each variable that needs to be monitored: name && address && length, set threshold, comparison method, timer interval (ns), etc.
-- `start_watch(watch_arg);` Start monitoring
-- Call `cancel_all_watch();` when you need to cancel monitoring
+监控 数值变量(给定 地址,长度), 达到设定条件打印系统内 Task 信息(用户态堆栈/内核态堆栈/调用链信息).
+- 支持多进程, 单个进程退出时,取消该进程的所有监控.
+- 相同定时间隔会分配到同一个定时器,一个定时器最多监控 32 个变量,全局最多 128 个定时器.
+    - 以上数量限制定义在 `source/module/monitor_timer.h`.
+    - `testcase/helloworld.c` 有测试到单进程 2049 个变量;
 
-When the set conditions are exceeded, the system stack information is printed and viewed with `dmesg`, as shown in the following example:
-- Within a timer, if multiple variables exceed the threshold, the stack information will not be output repeatedly;
-- The timer restart time after printing the stack is 1s, and the next round of monitoring will start after 1s.
+文件结构
 
 ```log
-[86245.364861] -------------------------------------
-[86245.364864] -------------watch monitor-----------
-[86245.364865] Threshold reached:
-                 name: temp0, threshold: 150 
-[86245.364866] Timestamp (ns): 1699589000606300743
-[86245.364867] Recent Load: 116.65, 126.83, 151.17
-[86245.365669] task: name lcore-worker-4, pid 803327
-[86245.365672] task: name lcore-worker-5, pid 803328
-[86245.365673] task: name lcore-worker-6, pid 803329
-[86245.365674] task: name lcore-worker-7, pid 803330
-[86245.365676] task: name lcore-worker-8, pid 803331
-[86245.365677] task: name lcore-worker-9, pid 803332
-[86245.365679] task: name lcore-worker-10, pid 803333
-[86245.365681] task: name lcore-worker-11, pid 803334
-[86245.365682] task: name lcore-worker-68, pid 803335
-[86245.365683] task: name lcore-worker-69, pid 803336
-[86245.365684] task: name lcore-worker-70, pid 803337
-[86245.365685] task: name lcore-worker-71, pid 803338
-[86245.365686] task: name lcore-worker-72, pid 803339
-[86245.365687] task: name lcore-worker-73, pid 803340
-[86245.365688] task: name lcore-worker-74, pid 803341
-[86245.365689] task: name lcore-worker-75, pid 803342
-[86245.365694] task: name pkt:worker-0, pid 803638
-[86245.365702]  hrtimer_nanosleep+0x8d/0x120
-[86245.365709]  __x64_sys_nanosleep+0x96/0xd0
-[86245.365711]  do_syscall_64+0x37/0x80
-[86245.365716]  entry_SYSCALL_64_after_hwframe+0x44/0xae
-[86245.365718] task: name pkt:worker-1, pid 803639
-[86245.365721]  hrtimer_nanosleep+0x8d/0x120
-[86245.365724]  __x64_sys_nanosleep+0x96/0xd0
-[86245.365726]  do_syscall_64+0x37/0x80
-[86245.365728]  entry_SYSCALL_64_after_hwframe+0x44/0xae
-[86245.365730] task: name pkt:worker-2, pid 803640
-[86245.365732]  hrtimer_nanosleep+0x8d/0x120
-[86245.365734]  __x64_sys_nanosleep+0x96/0xd0
-[86245.365737]  do_syscall_64+0x37/0x80
-[86245.365739]  entry_SYSCALL_64_after_hwframe+0x44/0xae
-[86245.365740] task: name pkt:worker-3, pid 803641
-[86245.365743]  hrtimer_nanosleep+0x8d/0x120
+├── build       // output
+├── source      // all source code
+│   ├── buffer  // 模块与用户空间通信的缓冲区
+│   ├── module  // 模块代码
+│   ├── uapi    // 用户空间接口
+│   ├── ucli    // 用户空间命令行工具
+│   └── ucli_py // 用户空间命令行 python (仅测试用,待完成)
+│       └── libunwind // python 解析堆栈信息移植库
+├── testcase    // 测试用例
+└── tools       // 测试工具
 ```
 
-### Parameter Description
+## 使用
+
+设定对变量监控有两种函数: 宏定义 或 定义 watch_arg 结构体
+- 都需要添加 `source/uapi` 下的头文件 `#include "monitor_user.h"`
+
+需要取消监控时调用 `cancel_watch();` variant_monitor 会取消该进程所有监控.
+- 当进程退出后,也会执行相同的操作,取消该进程所有监控.
+- 因此调用 `cancel_watch();` 是个可选项,但依然建议调用以避免可能的内存泄漏.
+
+获取 Task 信息是一项耗时操作,这里使用了 workqueue 处理,且一次处理后该定时器重启间隔默认为 5s.
+- 此值可以在 `/proc/variable_monitor/dump_reset_sec` 查看和修改.
+
+### 挂载驱动
+
+项目根目录
 
-start_watch passes in the watch_arg structure. The meaning of each field is as follows
-- name limit `MAX_NAME_LEN`(15) valid characters
+```bash
+# 编译加载模块
+make && insmod source/variable_monitor.ko
+# 卸载模块,清理编译文件
+# rmmod source/variable_monitor.ko && make clean
+# 仅在 `kernel 5.17.15-1.el8.x86_64` 测试,其他内核版本未测试.
+```
 
+### 宏定义
+
+示例如 `testcase/helloworld.c`, 对常见数值类型宏定义 方便使用:
+- 其他类型见 `source/uapi/monitor_user_sw.h`
 ```c
+// 传入变量名 | 地址 | 阈值
+START_WATCH_INT("temp", &temp, 150);
+START_WATCH_INT_LESS("temp", &temp, 150);
+```
+
+默认情况下,使用宏定义 定时器的时间间隔为 10us; 此值可以在 `/proc/variable_monitor/def_interval_ns` 查看和修改.
+
+### watch_arg 结构体
+
+如果需要对定时间隔等有更多控制,请定义 watch_arg 结构体,start_watch 启动监控:
+- 对每个需要监控的变量 设置: 名称 && 地址 && 长度, 设置阈值, 比较方式, 定时器间隔(ns) 等.
+- `start_watch(watch_arg);` 启动监控
+- 需要取消监控时调用 `cancel_watch();` 
+
+```c
+// start_watch 传入的是 watch_arg 结构体.各个字段意义如下
+// - name 限制 `MAX_NAME_LEN`(15) 个有效字符
 typedef struct
 {
     pid_t task_id;               // current process id
@@ -82,63 +89,156 @@ typedef struct
     unsigned char greater_flag;  // reverse flag (true: >, false: <)
     unsigned long time_ns;       // timer interval (ns)
 } watch_arg;
-```
 
-An initialization example
-
-```c
+//一个初始化示例
 watch_args = (watch_arg){
     .task_id = getpid(),
     .ptr = &temp,
     .name = "temp",
     .length_byte = sizeof(int),
-    .threshold = 150 + i,
+    .threshold = 150,
     .unsigned_flag = 0,
     .greater_flag = 1,
-    .time_ns = 2000 + (i / 33) * 5000
+    .time_ns = 2000 + 5000
 };
+start_watch(watch_args);
 ```
 
-## demo
+### 打印输出
 
-In the main project directory:
+定时器不断按照设定间隔轮询变量,当达到设定条件时,采集此时系统内符合要求的 Task 信息(用户态堆栈/内核态堆栈/调用链信息).
+- `dmesg` 可以查看到具体的超出设定条件的变量信息;
+- Task 信息被输出到缓存区,使用 ucli 工具查看.
 
-```bash
-make && insmod watch_module.ko
-./watch
+`dmesg` 打印示例如下
+
+```log
+[42865.640988] -------------------------------------
+[42865.640992] -----------variable monitor----------
+[42865.640993] 超出阈值：1701141698684973655
+[42865.640994]  : pid: 63936, name: temp0, ptr: 00000000bade6e61, threshold:110
+[42865.648068] -------------------------------------
+[42875.640703] -------------------------------------
+[42875.640706] -----------variable monitor----------
+[42875.640706] 超出阈值：1701141708684881779
+[42875.640708]  : pid: 63936, name: temp0, ptr: 00000000bade6e61, threshold:110
+[42875.640710]  : pid: 63936, name: temp1, ptr: 00000000ee645b96, threshold:111
+[42875.640711]  : pid: 63936, name: temp2, ptr: 00000000f62b7afe, threshold:112
+[42875.640711]  : pid: 63936, name: temp3, ptr: 00000000d100fa3c, threshold:113
+[42875.640712]  : pid: 63936, name: temp4, ptr: 000000006d31cae1, threshold:114
+[42875.640712]  : pid: 63936, name: temp5, ptr: 00000000723c7a2a, threshold:115
+[42875.640713]  : pid: 63936, name: temp6, ptr: 0000000026ef6e83, threshold:116
+[42875.640714]  : pid: 63936, name: temp7, ptr: 00000000fc1e5d5e, threshold:117
+[42875.640714]  : pid: 63936, name: temp8, ptr: 0000000069b2666e, threshold:118
+[42875.640715]  : pid: 63936, name: temp9, ptr: 000000000176263d, threshold:119
+[42875.648023] -------------------------------------
 ```
 
-You can see the printed stack information in dmesg
+默认情况下 `ucli` 编译后在 build 文件夹下
 
-```bash
-# Unload module and clean compile files
-rmmod watch_module.ko && make clean
+`ucli > output`
+- ucli 会将缓存区内容解析后输出到 `output` 文件中.
+- **此操作会清空缓存区**
+
+`ucli` 工具输出示例如下(详情见 output_example)
+- userstack 是 testcase 下的堆栈信息测试程序.
+
+```log
+##CGROUP:[/]  51666      [510]  采样命中[D]
+    进程信息： [/ / userstack]， PID： 51666 / 51666
+##C++ pid 51666
+    用户态堆栈SP：7ffcd5822298, BP:2, IP:7f071c720838
+#~        0x7f071c720838 __GI___nanosleep ([symbol])
+#~        0x7f071c72076e __sleep ([symbol])
+#~        0x400a08 customFunction1 ([symbol])
+#~        0x400a64 customFunction3 ([symbol])
+#~        0x400a42 customFunction2 ([symbol])
+#~        0x400a21 customFunction1 ([symbol])
+#~        0x400a64 customFunction3 ([symbol])
+#~        0x400a42 customFunction2 ([symbol])
+#~        0x400a21 customFunction1 ([symbol])
+#~        0x400a64 customFunction3 ([symbol])
+#~        0x400a42 customFunction2 ([symbol])
+#~        0x400a21 customFunction1 ([symbol])
+#~        0x400a64 customFunction3 ([symbol])
+#~        0x400a42 customFunction2 ([symbol])
+#~        0x400a21 customFunction1 ([symbol])
+#~        0x400a64 customFunction3 ([symbol])
+#~        0x400a42 customFunction2 ([symbol])
+#~        0x400a21 customFunction1 ([symbol])
+#~        0x400a64 customFunction3 ([symbol])
+#~        0x400a42 customFunction2 ([symbol])
+#~        0x400a21 customFunction1 ([symbol])
+#~        0x400a64 customFunction3 ([symbol])
+#~        0x400a42 customFunction2 ([symbol])
+#~        0x400a21 customFunction1 ([symbol])
+#~        0x400a64 customFunction3 ([symbol])
+#~        0x400a42 customFunction2 ([symbol])
+#~        0x400a21 customFunction1 ([symbol])
+#~        0x400a64 customFunction3 ([symbol])
+#~        0x400a42 customFunction2 ([symbol])
+#~        0x400a21 customFunction1 ([symbol])
+#~        0x400a64 customFunction3 ([symbol])
+#~        0x400a42 customFunction2 ([symbol])
+#~        0x400a21 customFunction1 ([symbol])
+#~        0x400a75 main ([symbol])
+#~        0x7f071c661d85 __libc_start_main ([symbol])
+#~        0x40081e _start ([symbol])
+    内核态堆栈：
+#@        0xffffffff811730dd hrtimer_nanosleep  ([kernel.kallsyms])
+#@        0xffffffff811733a6 __x64_sys_nanosleep  ([kernel.kallsyms])
+#@        0xffffffff819fa117 do_syscall_64  ([kernel.kallsyms])
+#@        0xffffffff81c0007c entry_SYSCALL_64_after_hwframe  ([kernel.kallsyms])
+#@        0xffffffff819fa117 do_syscall_64  ([kernel.kallsyms])
+#@        0xffffffff81c0007c entry_SYSCALL_64_after_hwframe  ([kernel.kallsyms])
+#@        0xffffffff819fa117 do_syscall_64  ([kernel.kallsyms])
+#@        0xffffffff81c0007c entry_SYSCALL_64_after_hwframe  ([kernel.kallsyms])
+#*        0xffffffffffffff userstack (UNKNOWN)
+    进程链信息：
+#^        0xffffffffffffff ./build/userstack  (UNKNOWN)
+#^        0xffffffffffffff /bin/bash --init-file /root/.vscode-server-insiders/cli/servers/Insiders-ca9da6c177fc4cf7429e1d0c1c52f710d6d953c6/server/out/vs/workbench/contrib/terminal/browser/media/shellIntegration-bash.sh  (UNKNOWN)
+#^        0xffffffffffffff /root/.vscode-server-insiders/cli/servers/Insiders-ca9da6c177fc4cf7429e1d0c1c52f710d6d953c6/server/node /root/.vscode-server-insiders/cli/servers/Insiders-ca9da6c177fc4cf7429e1d0c1c52f710d6d953c6/server/out/bootstrap-fork --type=ptyHost --logsPath /root/ (UNKNOWN)
+#^        0xffffffffffffff /root/.vscode-server-insiders/cli/servers/Insiders-ca9da6c177fc4cf7429e1d0c1c52f710d6d953c6/server/node /root/.vscode-server-insiders/cli/servers/Insiders-ca9da6c177fc4cf7429e1d0c1c52f710d6d953c6/server/out/server-main.js --connection-token=remotessh --a (UNKNOWN)
+#^        0xffffffffffffff sh /root/.vscode-server-insiders/cli/servers/Insiders-ca9da6c177fc4cf7429e1d0c1c52f710d6d953c6/server/bin/code-server-insiders --connection-token=remotessh --accept-server-license-terms --start-server --enable-remote-auto-shutdown --socket-path=/tmp/code (UNKNOWN)
+#^        0xffffffffffffff /root/.vscode-server-insiders/code-insiders-ca9da6c177fc4cf7429e1d0c1c52f710d6d953c6 command-shell --cli-data-dir /root/.vscode-server-insiders/cli --on-port --require-token b5a047063eb7  (UNKNOWN)
+#^        0xffffffffffffff /usr/lib/systemd/systemd --switched-root --system --deserialize 17  (UNKNOWN)
+##
 ```
 
-Only tested on kernel 5.17.15-1.el8.x86_64.
+## demo
+
+usercase 文件夹下
+- `helloworld.c`: 测试大量变量监控
+- `userstack.c`: 测试用户态堆栈输出
+- `hptest.c`: 测试 hugePage 挂载
+
+## 其他
 
-## Other
+程序分为两部分: 字符设备 和 用户空间接口, 两者通过 ioctl 通信.
 
-The program is divided into two parts: character device and user space interface, both of which communicate through ioctl.
+用户空间地址访问
+- 用户程序传入的变量 虚拟地址, 使用 `get_user_pages_remote` 获取地址所在内存页, `kmap` 将其映射到内核.
+    - 192.168.40.204 环境下,HugeTLB Pages 测试挂载正常.
+- 内存页地址 + 偏移量存入定时器对应的 `kernel_watch_arg` 中, hrTimer 轮询时访问 `kernel_watch_arg` 得到真实值.
 
-User space address access
-- The variable virtual address passed in by the user program, use `get_user_pages_remote` to obtain the memory page where the address is located, and `kmap` maps it to the kernel.
-     - In the 192.168.40.204 environment, the HugeTLB Pages test mounts normally.
-- The memory page address + offset is stored in the `kernel_watch_arg` corresponding to the timer, and hrTimer accesses `kernel_watch_arg` when polling to get the real value.
+定时器分组
+- hrTimer 数据结构定义在全局数组 `kernel_wtimer_list`.分配定时器时,会检查遍历 `kernel_wtimer_list` 比较定时器间隔,
+- 相同定时间隔的 watch 分配到同一组,对应同一个 hrTimer. 
+- 若一个定时器监控变量数量超过 `TIMER_MAX_WATCH_NUM` (32),则会创建一个新的 hrTimer.
+- hrTimer 的总数量(`kernel_wtimer_list` 数组长度)限制是 `MAX_TIMER_NUM`(128).
 
-timer grouping
-- The hrTimer data structure is defined in the global array `kernel_wtimer_list`. When allocating a timer, it will check the traversal `kernel_wtimer_list` to compare the timer interval.
-- Watches with the same timing interval are assigned to the same group and correspond to the same hrTimer.
-- If the number of variables monitored by a timer exceeds `TIMER_MAX_WATCH_NUM` (32), a new hrTimer will be created.
-- The total number of hrTimers (`kernel_wtimer_list` array length) limit is `MAX_TIMER_NUM`(128).
+内存页 mount/unmount
+- `get_user_pages_remote`/ `kmap` 会增加对应的计数,需要对等的 `put_page`/`kunmap`.
+- 一个模块内全局链表 `watch_local_memory_list` 存储每一个成功挂载的变量对应的 page 和 kt,执行字符设备的 close 操作时,遍历并卸载.
 
-Memory page mount/unmount
-- `get_user_pages_remote`/ `kmap` will increase the corresponding count and requires the equivalent `put_page`/`kunmap`.
-- A global linked list in the module `watch_local_memory_list` stores the page and kt corresponding to each successfully mounted variable. When performing the close operation of the character device, it is traversed and unloaded.
+variable monitor 添加/删除
+- kernel_watch_arg 数据结构中有 pid 的成员变量,但添加变量监控时,不按照进程区分.
+- 删除时遍历全部监控变量,比较 pid.
+- 删除造成的缺位,将最后的变量移动到空位, sentinel--; hrTimer 同理.
 
-Stack output conditions: The conditions are referenced from [diagnose-tools::load.c](https://github.com/alibaba/diagnose-tools/blob/e285bc4626a7d207eabd4a69cb276e1a3b1b7c76/SOURCE/module/kernel/load.c#L209)
-- `TASK` must satisfy TASK_RUNNING and `__task_contributes_to_load`.
-- `__task_contributes_to_load` corresponds to the kernel macro `task_contributes_to_loa`.
+堆栈输出条件: 条件参考自  [diagnose-tools::load.c](https://github.com/alibaba/diagnose-tools/blob/e285bc4626a7d207eabd4a69cb276e1a3b1b7c76/SOURCE/module/kernel/load.c#L209)
+- `TASK` 要满足 TASK_RUNNING 和 `__task_contributes_to_load` 和 `TASK_IDLE`(可能有阻塞进程).
+- `__task_contributes_to_load` 对应内核宏 `task_contributes_to_loa`.
 
 ```c
 // https://www.spinics.net/lists/kernel/msg3582022.html