creport: optimize ScopedFile performance

stratosphere/creport/source/creport_crash_report.cpp

@@ -26,6 +26,8 @@ namespace ams::creport {
         static_assert(DyingMessageAddressOffset == AMS_OFFSETOF(ams::svc::aarch64::ProcessLocalRegion, dying_message_region_address));
         static_assert(DyingMessageAddressOffset == AMS_OFFSETOF(ams::svc::aarch32::ProcessLocalRegion, dying_message_region_address));
 
+        constexpr size_t CrashReportDataCacheSize = 256_KB;
+
         /* Helper functions. */
         bool TryGetCurrentTimestamp(u64 *out) {
             /* Clear output. */
@@ -307,7 +309,15 @@ namespace ams::creport {
             /* Save crash report. */
             util::SNPrintf(file_path, sizeof(file_path), "sdmc:/atmosphere/crash_reports/%011lu_%016lx.log", timestamp, m_process_info.program_id);
             {
-                ScopedFile file(file_path);
+                /* Try to allocate data cache. */
+                void * const data_cache = lmem::AllocateFromExpHeap(m_heap_handle, CrashReportDataCacheSize + os::MemoryPageSize);
+                ON_SCOPE_EXIT { if (data_cache != nullptr) { lmem::FreeToExpHeap(m_heap_handle, data_cache); } };
+
+                /* Align up the data cache. This is safe because null will align up to null. */
+                void * const aligned_cache = reinterpret_cast<void *>(util::AlignUp(reinterpret_cast<uintptr_t>(data_cache), os::MemoryPageSize));
+
+                /* Open and save the file using the cache. */
+                ScopedFile file(file_path, aligned_cache, aligned_cache != nullptr ? CrashReportDataCacheSize : 0);
                 if (file.IsOpen()) {
                     this->SaveToFile(file);
                 }

stratosphere/creport/source/creport_modules.cpp

@@ -46,7 +46,7 @@ namespace ams::creport {
     }
 
     void ModuleList::SaveToFile(ScopedFile &file) {
-        file.WriteFormat("    Number of Modules:           %zu\n", m_num_modules);
+        file.WriteFormat("    Number of Modules:           %02zu\n", m_num_modules);
         for (size_t i = 0; i < m_num_modules; i++) {
             const auto& module = m_modules[i];
             file.WriteFormat("    Module %02zu:\n", i);

stratosphere/creport/source/creport_scoped_file.cpp

@@ -60,22 +60,24 @@ namespace ams::creport {
 
             /* Print the line prefix. */
             if (first) {
-                this->WriteFormat("%s", prefix);
+                this->Write(prefix, prefix_len);
                 first = false;
             } else {
-                this->WriteFormat("%*s", prefix_len, "");
+                std::memset(g_format_buffer, ' ', prefix_len);
+                this->Write(g_format_buffer, prefix_len);
             }
 
             /* Dump up to 0x20 of hex memory. */
             {
                 char hex[MaximumLineLength * 2 + 2] = {};
                 for (size_t i = 0; i < cur_size; i++) {
-                    util::SNPrintf(hex + i * 2, 3, "%02X", data_u8[data_ofs++]);
+                    hex[i * 2 + 0] = "0123456789ABCDEF"[data_u8[data_ofs] >> 4];
+                    hex[i * 2 + 1] = "0123456789ABCDEF"[data_u8[data_ofs] & 0xF];
+                    ++data_ofs;
                 }
                 hex[cur_size * 2 + 0] = '\n';
-                hex[cur_size * 2 + 1] = '\x00';
 
-                this->WriteString(hex);
+                this->Write(hex, cur_size * 2 + 1);
             }
 
             /* Continue. */
@@ -83,16 +85,40 @@ namespace ams::creport {
         }
     }
 
+
     void ScopedFile::Write(const void *data, size_t size) {
         /* If we're not open, we can't write. */
         if (!this->IsOpen()) {
             return;
         }
 
+        /* If we have a cache, write to it. */
+        if (m_cache != nullptr) {
+            /* Write into the cache, if we can. */
+            if (m_cache_size - m_cache_offset >= size || R_SUCCEEDED(this->TryWriteCache())) {
+                std::memcpy(m_cache + m_cache_offset, data, size);
+                m_cache_offset += size;
+            }
+        } else {
             /* Advance, if we write successfully. */
-        if (R_SUCCEEDED(fs::WriteFile(m_file, m_offset, data, size, fs::WriteOption::Flush))) {
+            if (R_SUCCEEDED(fs::WriteFile(m_file, m_offset, data, size, fs::WriteOption::None))) {
                 m_offset += size;
             }
         }
+    }
+
+    Result ScopedFile::TryWriteCache() {
+        /* If there's no cached data, there's nothing to do. */
+        R_SUCCEED_IF(m_cache_offset == 0);
+
+        /* Try to write any cached data. */
+        R_TRY(fs::WriteFile(m_file, m_offset, m_cache, m_cache_offset, fs::WriteOption::None));
+
+        /* Update our extents. */
+        m_offset += m_cache_offset;
+        m_cache_offset = 0;
+
+        R_SUCCEED();
+    }
 
 }

stratosphere/creport/source/creport_scoped_file.hpp

@@ -25,8 +25,11 @@ namespace ams::creport {
             fs::FileHandle m_file;
             s64 m_offset;
             bool m_opened;
+            u8 *m_cache;
+            const size_t m_cache_size;
+            s64 m_cache_offset;
         public:
-            ScopedFile(const char *path) : m_file(), m_offset(), m_opened(false) {
+            ScopedFile(const char *path, void *cache = nullptr, size_t cache_size = 0) : m_file(), m_offset(), m_opened(false), m_cache(static_cast<u8*>(cache)), m_cache_size(cache_size), m_cache_offset(0) {
                 if (R_SUCCEEDED(fs::CreateFile(path, 0))) {
                     m_opened = R_SUCCEEDED(fs::OpenFile(std::addressof(m_file), path, fs::OpenMode_Write | fs::OpenMode_AllowAppend));
                 }
@@ -34,6 +37,10 @@ namespace ams::creport {
 
             ~ScopedFile() {
                 if (m_opened) {
+                    if (m_cache != nullptr) {
+                        this->TryWriteCache();
+                    }
+                    fs::FlushFile(m_file);
                     fs::CloseFile(m_file);
                 }
             }
@@ -47,6 +54,8 @@ namespace ams::creport {
             void DumpMemory(const char *prefix, const void *data, size_t size);
 
             void Write(const void *data, size_t size);
+        private:
+            Result TryWriteCache();
     };
 
 }