Implemented --stats command-line option.

Closes #19.

Author: xvitaly

src/app/application/application.cpp

@@ -50,6 +50,22 @@ bool Application::CheckIfRunningBySuperUser()
     return false;
 }
 
+int Application::GetUsageStats()
+{
+    ZSwapDebug ZSwapDebugger;
+    std::cout << fmt::format("Duplicate entries count: {0}.", ZSwapDebugger.GetDuplicateEntry()) << std::endl;
+    std::cout << fmt::format("Pool limit hit: {0}.", ZSwapDebugger.GetPoolLimitHit()) << std::endl;
+    std::cout << fmt::format("Pool total size: {0}.", ZSwapDebugger.GetPoolTotalSize()) << std::endl;
+    std::cout << fmt::format("Reject allocation failures: {0}.", ZSwapDebugger.GetRejectAllocFail()) << std::endl;
+    std::cout << fmt::format("Reject compression poor: {0}.", ZSwapDebugger.GetRejectCompressPoor()) << std::endl;
+    std::cout << fmt::format("Reject Kmemcache failures: {0}.", ZSwapDebugger.GetRejectKmemCacheFail()) << std::endl;
+    std::cout << fmt::format("Reject reclaim failures: {0}.", ZSwapDebugger.GetRejectReclaimFail()) << std::endl;
+    std::cout << fmt::format("Same filled pages count: {0}.", ZSwapDebugger.GetSameFilledPages()) << std::endl;
+    std::cout << fmt::format("Stored pages count: {0}.", ZSwapDebugger.GetStoredPages()) << std::endl;
+    std::cout << fmt::format("Written back pages count: {0}.", ZSwapDebugger.GetWrittenBackPages()) << std::endl;
+    return 0;
+}
+
 void Application::ExecuteEnv()
 {
     const std::string ZSwapEnabledEnv = CWrappers::GetEnv("ZSWAP_ENABLED_VALUE");
@@ -80,6 +96,7 @@ void Application::ExecuteCmdLine(const cxxopts::ParseResult& CmdLine)
 int Application::Run(const cxxopts::ParseResult& CmdLine)
 {
     if (CheckIfRunningBySuperUser()) return 1;
+    if (CmdLine.count("stats")) return GetUsageStats();
     if (CmdLine.count("env")) ExecuteEnv(); else ExecuteCmdLine(CmdLine);
     return 0;
 }

src/app/application/application.hpp

@@ -30,6 +30,7 @@
 #include "cwrappers/cwrappers.hpp"
 #include "zswapworker/zswapworker.hpp"
 #include "zswapobject/zswapobject.hpp"
+#include "zswapdebug/zswapdebug.hpp"
 
 class Application
 {
@@ -49,6 +50,7 @@ class Application
     bool CheckIfRunningBySuperUser();
     void ExecuteEnv();
     void ExecuteCmdLine(const cxxopts::ParseResult&);
+    int GetUsageStats();
 };
 
 #endif // APPLICATION_H

src/app/main.cpp

@@ -28,6 +28,7 @@ int main(int argc, char** argv)
     cxxopts::Options options("zswap-cli", "Command-line tool to control ZSwap Linux kernel module.");
     options.add_options()
             ("env", "Get options from environment variables instead of cmdline.", cxxopts::value<bool>()->default_value("false"))
+            ("stats", "Get statistics of ZSwap usage and current settings.", cxxopts::value<bool>()->default_value("false"))
             ("e,enabled", "Enable or disable ZSwap kernel module.", cxxopts::value<std::string>())
             ("s,same_filled_pages_enabled", "Enable or disable memory pages deduplication.", cxxopts::value<std::string>())
             ("p,max_pool_percent", "The maximum percentage of memory that the compressed pool can occupy.", cxxopts::value<std::string>())