TASK06: SUBTASK01, SUBTASK02 Add user-space program with kernel module Vitaliy.Zhyrko

06_memory/dump_part01.txt

@@ -0,0 +1,70 @@
+../bin/test_mem
+malloc: It took  0 s, 0 ms,  0 µs, 675 ns,  size 1
+calloc: It took  0 s, 0 ms,  0 µs, 878 ns,  size 1
+alloca: It took  0 s, 0 ms,  0 µs, 101 ns,  size 1
+malloc: It took  0 s, 0 ms,  0 µs, 158 ns,  size 2
+calloc: It took  0 s, 0 ms,  0 µs, 192 ns,  size 2
+alloca: It took  0 s, 0 ms,  0 µs, 65 ns,  size 2
+malloc: It took  0 s, 0 ms,  0 µs, 66 ns,  size 4
+calloc: It took  0 s, 0 ms,  0 µs, 181 ns,  size 4
+alloca: It took  0 s, 0 ms,  0 µs, 68 ns,  size 4
+malloc: It took  0 s, 0 ms,  0 µs, 68 ns,  size 8
+calloc: It took  0 s, 0 ms,  0 µs, 174 ns,  size 8
+alloca: It took  0 s, 0 ms,  0 µs, 67 ns,  size 8
+malloc: It took  0 s, 0 ms,  0 µs, 138 ns,  size 16
+calloc: It took  0 s, 0 ms,  0 µs, 258 ns,  size 16
+alloca: It took  0 s, 0 ms,  0 µs, 67 ns,  size 16
+malloc: It took  0 s, 0 ms,  0 µs, 126 ns,  size 32
+calloc: It took  0 s, 0 ms,  0 µs, 228 ns,  size 32
+alloca: It took  0 s, 0 ms,  0 µs, 68 ns,  size 32
+malloc: It took  0 s, 0 ms,  0 µs, 85 ns,  size 64
+calloc: It took  0 s, 0 ms,  0 µs, 214 ns,  size 64
+alloca: It took  0 s, 0 ms,  0 µs, 67 ns,  size 64
+malloc: It took  0 s, 0 ms,  0 µs, 105 ns,  size 128
+calloc: It took  0 s, 0 ms,  0 µs, 548 ns,  size 128
+alloca: It took  0 s, 0 ms,  0 µs, 67 ns,  size 128
+malloc: It took  0 s, 0 ms,  0 µs, 90 ns,  size 256
+calloc: It took  0 s, 0 ms,  0 µs, 225 ns,  size 256
+alloca: It took  0 s, 0 ms,  0 µs, 66 ns,  size 256
+malloc: It took  0 s, 0 ms,  0 µs, 127 ns,  size 512
+calloc: It took  0 s, 0 ms,  0 µs, 286 ns,  size 512
+alloca: It took  0 s, 0 ms,  0 µs, 69 ns,  size 512
+malloc: It took  0 s, 0 ms,  0 µs, 165 ns,  size 1024
+calloc: It took  0 s, 0 ms,  3 µs, 3081 ns,  size 1024
+alloca: It took  0 s, 0 ms,  0 µs, 69 ns,  size 1024
+malloc: It took  0 s, 0 ms,  0 µs, 136 ns,  size 2048
+calloc: It took  0 s, 0 ms,  0 µs, 286 ns,  size 2048
+alloca: It took  0 s, 0 ms,  0 µs, 68 ns,  size 2048
+malloc: It took  0 s, 0 ms,  2 µs, 2773 ns,  size 4096
+calloc: It took  0 s, 0 ms,  0 µs, 346 ns,  size 4096
+alloca: It took  0 s, 0 ms,  2 µs, 2853 ns,  size 4096
+malloc: It took  0 s, 0 ms,  4 µs, 4773 ns,  size 8192
+calloc: It took  0 s, 0 ms,  0 µs, 431 ns,  size 8192
+alloca: It took  0 s, 0 ms,  2 µs, 2678 ns,  size 8192
+malloc: It took  0 s, 0 ms,  2 µs, 2552 ns,  size 16384
+calloc: It took  0 s, 0 ms,  3 µs, 3564 ns,  size 16384
+alloca: It took  0 s, 0 ms,  2 µs, 2747 ns,  size 16384
+malloc: It took  0 s, 0 ms,  2 µs, 2739 ns,  size 32768
+calloc: It took  0 s, 0 ms,  10 µs, 10208 ns,  size 32768
+alloca: It took  0 s, 0 ms,  2 µs, 2680 ns,  size 32768
+malloc: It took  0 s, 0 ms,  6 µs, 6609 ns,  size 65536
+calloc: It took  0 s, 0 ms,  22 µs, 22841 ns,  size 65536
+alloca: It took  0 s, 0 ms,  3 µs, 3782 ns,  size 65536
+malloc: It took  0 s, 0 ms,  2 µs, 2604 ns,  size 131072
+calloc: It took  0 s, 0 ms,  49 µs, 49530 ns,  size 131072
+alloca: It took  0 s, 0 ms,  3 µs, 3044 ns,  size 131072
+malloc: It took  0 s, 0 ms,  6 µs, 6497 ns,  size 262144
+calloc: It took  0 s, 0 ms,  17 µs, 17151 ns,  size 262144
+alloca: It took  0 s, 0 ms,  3 µs, 3739 ns,  size 262144
+malloc: It took  0 s, 0 ms,  7 µs, 7814 ns,  size 524288
+calloc: It took  0 s, 0 ms,  253 µs, 253306 ns,  size 524288
+alloca: It took  0 s, 0 ms,  4 µs, 4085 ns,  size 524288
+malloc: It took  0 s, 0 ms,  7 µs, 7261 ns,  size 1048576
+calloc: It took  0 s, 0 ms,  267 µs, 267541 ns,  size 1048576
+alloca: It took  0 s, 0 ms,  4 µs, 4989 ns,  size 1048576
+malloc: It took  0 s, 0 ms,  7 µs, 7156 ns,  size 2097152
+calloc: It took  0 s, 0 ms,  547 µs, 547159 ns,  size 2097152
+alloca: It took  0 s, 0 ms,  5 µs, 5332 ns,  size 2097152
+malloc: It took  0 s, 0 ms,  7 µs, 7051 ns,  size 4194304
+calloc: It took  0 s, 1 ms,  1093 µs, 1093337 ns,  size 4194304
+make: *** [Makefile:21: test] Segmentation fault (core dumped)

06_memory/dump_part02.txt

@@ -0,0 +1,6 @@
+[ 1579.250693] test_module loaded
+[ 1579.250694] al_name           buf_size        all_time        fr_time
+[ 1579.250695] kmalloc:          100,            59 ns,          35 ns
+[ 1579.250695] kzalloc:          100,            50 ns,          26 ns
+[ 1579.250705] vmalloc:          4096,           9280 ns,        17 ns
+[ 1579.250705] get_free_pages:   0,              79 ns,          68 ns

06_memory/part01/Makefile

@@ -0,0 +1,21 @@
+TARGET=test_mem
+BIN=../bin
+
+CC=g++
+AM_CXXFLAGS = -std=c++11
+
+all: bin $(TARGET)
+
+bin:
+	mkdir -p $(BIN)
+
+$(TARGET): $(TARGET).c
+	$(CC) -o $(BIN)/$@ $< 
+
+clean:
+	@rm -vf $(BIN)/$(TARGET) *.o
+
+clear: clean
+
+test:
+	$(BIN)/$(TARGET)

06_memory/part01/test_mem.c

@@ -0,0 +1,87 @@
+//#include <stdio.h>
+//#include <stdlib.h>
+#include <malloc.h>
+#include <ratio>
+#include <chrono>
+#include <iostream>
+
+using namespace std::chrono;
+
+static size_t size = 1;
+
+static std::chrono::time_point<std::chrono::steady_clock> start =
+    std::chrono::steady_clock::now();
+
+void StartTimer()
+{
+    start = std::chrono::steady_clock::now();
+}
+
+void StopTimer(const char * name_timer)
+{
+    const auto end = std::chrono::steady_clock::now();
+    std::cout
+          << name_timer << ": It took  "
+          << (end - start) / 1s << " s, "
+          << (end - start) / 1ms << " ms,  "
+          << std::chrono::duration_cast<std::chrono::microseconds>(end - start).count() << " µs, "
+          << std::chrono::duration_cast<std::chrono::nanoseconds>(end - start).count() << " ns, "
+          << " size " << size << "\n";
+}
+
+
+int main(void)
+{
+    int counter=1000;
+
+    while(1)
+    {
+        StartTimer();
+        char *buf = (char*)malloc(size);
+        StopTimer("malloc");
+
+        if(!buf)
+        {
+            std::cout << "Error: size - " << size << std::endl;
+            break;
+        }
+        else {
+            //printf( "malloc size - %ld\n" , size);
+            free(buf);
+        }
+
+
+        StartTimer();
+        buf = (char*)calloc(1, size);
+        StopTimer("calloc");
+
+        if(!buf)
+        {
+            std::cout << "Error: size - " << size << std::endl;
+            break;
+        }
+        else {
+            //printf( "calloc size - %ld\n" , size);
+            free(buf);
+        }
+
+        StartTimer();
+        buf = (char *)alloca(size);
+        StopTimer("alloca");
+
+        if(!buf)
+        {
+            std::cout << "Error: size - " << size << std::endl;
+            break;
+        }
+        else {
+            //printf( "alloca size - %ld\n" , size);
+        }
+
+        size*=2;
+
+        if(!counter--)
+            break;
+    }
+    return 0;
+}

06_memory/part02/Makefile

@@ -0,0 +1,16 @@
+TARGET=test_mem
+BIN=../bin
+
+obj-m = $(TARGET).o
+
+all:
+	make -C /lib/modules/$(shell uname -r)/build M=$(PWD) modules
+clean:
+	make -C /lib/modules/$(shell uname -r)/build M=$(PWD) clean
+
+test: #all
+	sudo dmesg -C
+	- sudo insmod ./$(TARGET).ko
+	#sudo rmmod $(TARGET)
+	sudo dmesg
+

06_memory/part02/check.sh

@@ -0,0 +1,7 @@
+#!/bin/bash
+set et ts=4 sts=4 sw=4
+
+CURRENT=$(uname -r)
+#BUILD_KERNEL=/lib/modules/$CURRENT/build
+BUILD_KERNEL=~/projects/LinuxKernelCoursePro/kernel/buildroot-2021.02.7/output/build/linux-5.10.10/
+$BUILD_KERNEL/scripts/checkpatch.pl -f --no-tree ./test_mem.c #--fix

06_memory/part02/test_mem.c

@@ -0,0 +1,160 @@
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/version.h>
+
+#define MODULE_TAG      "test_module "
+#define BUFFER_SIZE 100
+
+static char *proc_buffer;
+u64 start1, start2;
+u64 end1, end2;
+size_t size;
+
+static const char * const mem_cr_names[] = {
+	"kmalloc",
+	"kzalloc",
+	"vmalloc",
+	"get_free_pages",
+};
+
+enum mem_cr_type {
+	mem_cr_kmalloc = 0,
+	mem_cr_kzalloc = 1,
+	mem_cr_vmalloc = 2,
+	mem_cr_get_free_pages = 3,
+};
+
+void ShowHeader(void)
+{
+	pr_info("al_name \t\t buf_size \t all_time \t fr_time");
+}
+
+void ShowReport(const char *name_timer)
+{
+	pr_info("%s: \t %ld, \t\t %lld ns, \t %lld ns\n",
+	    name_timer, size, end1-start1, end2-start2);
+}
+
+void StartTimer1(void)
+{
+	start1 = ktime_get_ns();
+}
+
+void StopTimer1StartTimer2(void)
+{
+	end1 = ktime_get_ns();
+	start2 = ktime_get_ns();
+}
+
+void StopTimer(void)
+{
+	end2 = ktime_get_ns();
+}
+
+static int create_buffer(int value)
+{
+	int ret = 0;
+
+	switch (value) {
+	case mem_cr_kmalloc:
+		size = BUFFER_SIZE;
+		proc_buffer = kmalloc(size, GFP_KERNEL);
+		break;
+	case mem_cr_kzalloc:
+		size = BUFFER_SIZE;
+		proc_buffer = kzalloc(size, GFP_KERNEL);
+		break;
+	case mem_cr_vmalloc:
+		size = PAGE_SIZE;
+		proc_buffer = vmalloc(size);
+		break;
+	case mem_cr_get_free_pages:
+		size = 0;
+		proc_buffer = (char *)__get_free_pages(GFP_KERNEL, 0);
+		break;
+	}
+	if (proc_buffer == NULL)
+		ret =  -ENOMEM;
+	return ret;
+}
+
+static void cleanup_buffer(int value)
+{
+	if (proc_buffer) {
+		switch (value) {
+		case mem_cr_kmalloc:
+			kfree(proc_buffer);
+			break;
+		case mem_cr_kzalloc:
+			kfree(proc_buffer);
+			break;
+		case mem_cr_vmalloc:
+			vfree(proc_buffer);
+			break;
+		case mem_cr_get_free_pages:
+			free_pages((unsigned long)proc_buffer, 0);
+			break;
+	}
+	proc_buffer = NULL;
+	}
+}
+
+
+static int __init example_init(void)
+{
+	int err;
+
+	pr_notice(MODULE_TAG "loaded\n");
+
+	ShowHeader();
+
+	StartTimer1();
+	err = create_buffer(mem_cr_kmalloc);
+	StopTimer1StartTimer2();
+	cleanup_buffer(mem_cr_kmalloc);
+	StopTimer();
+	ShowReport(mem_cr_names[mem_cr_kmalloc]);
+
+	StartTimer1();
+	err = create_buffer(mem_cr_kzalloc);
+	StopTimer1StartTimer2();
+	cleanup_buffer(mem_cr_kzalloc);
+	StopTimer();
+	ShowReport(mem_cr_names[mem_cr_kzalloc]);
+
+	StartTimer1();
+	err = create_buffer(mem_cr_vmalloc);
+	StopTimer1StartTimer2();
+	StopTimer();
+	ShowReport(mem_cr_names[mem_cr_vmalloc]);
+
+	StartTimer1();
+	err = create_buffer(mem_cr_get_free_pages);
+	StopTimer1StartTimer2();
+	cleanup_buffer(mem_cr_get_free_pages);
+	StopTimer();
+	ShowReport(mem_cr_names[mem_cr_get_free_pages]);
+
+	return -1;
+
+error:
+	pr_err(MODULE_TAG "failed to load\n");
+	return err;
+}
+
+static void __exit example_exit(void)
+{
+	pr_notice(MODULE_TAG "exited\n");
+}
+
+module_init(example_init);
+module_exit(example_exit);
+
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Vitaliy Zhyrko vitaliyzh@gmail.com");
+MODULE_DESCRIPTION("A simple example Linux module.");
+MODULE_VERSION("0.01");