scheduler: implement nice

kernel-src/arch/x86-64/syscall.asm

@@ -92,6 +92,7 @@ extern syscall_sigtimedwait
 extern syscall_sigpending
 extern syscall_killthread
 extern syscall_shutdown
+extern syscall_nice
 syscalltab:
 dq syscall_print
 dq syscall_mmap
@@ -186,7 +187,8 @@ dq syscall_sigtimedwait
 dq syscall_sigpending
 dq syscall_killthread
 dq syscall_shutdown
-syscallcount equ 93
+dq syscall_nice
+syscallcount equ 94
 section .text
 global arch_syscall_entry
 ; on entry:

kernel-src/arch/x86-64/syscalllog.c

@@ -5,7 +5,7 @@
 
 #ifdef SYSCALL_LOGGING
 
-#define SYSCALL_COUNT 93
+#define SYSCALL_COUNT 94
 #define LOGSTR(x) arch_e9_puts(x)
 
 static char *name[] = {
@@ -101,7 +101,8 @@ static char *name[] = {
 	"sigtimedwait",
 	"sigpending",
 	"killthread",
-	"shutdown"
+	"shutdown",
+	"nice"
 };
 
 static char *args[] = {
@@ -195,9 +196,10 @@ static char *args[] = {
 	"egid %d", // setegid
 	"sigset %p", // sigsuspend
 	"sigset %p info %p, timespec %p", // sigtimedwait
-	"sigset %p\n", // sigpending
+	"sigset %p", // sigpending
 	"pid %d tid %d signal %d", // killthread
-	"how %d" // shutdown
+	"how %d", // shutdown
+	"off %d" // nice
 };
 
 #endif

kernel-src/include/kernel/auth.h

@@ -38,6 +38,7 @@
 #define AUTH_ACTIONS_CRED_SETEGID	32
 
 #define AUTH_ACTIONS_PROCESS_SIGNAL	1
+#define AUTH_ACTIONS_PROCESS_NICE	2
 
 #define AUTH_ACTIONS_NETWORK_CONFIGURE		1
 #define AUTH_ACTIONS_NETWORK_BINDRESERVED	2

kernel-src/include/kernel/proc.h

@@ -41,6 +41,7 @@ typedef struct proc_t {
 	spinlock_t nodeslock;
 	semaphore_t waitsem;
 	spinlock_t exiting;
+	int nice;
 
 	spinlock_t jobctllock;
 	struct {

kernel-src/include/kernel/scheduler.h

@@ -13,6 +13,8 @@
 
 #define SCHED_RUN_QUEUE_SIZE 32
 #define SCHED_MAX_INTERACTIVITY 100
+#define SCHED_NICE_MAX  19
+#define SCHED_NICE_MIN -20
 
 typedef struct {
 	 struct {

kernel-src/include/kernel/thread.h

@@ -37,7 +37,6 @@ typedef struct thread_t {
 	vmmcontext_t *vmmctx;
 	tid_t tid;
 	int flags;
-	long priority;
 	bool sleepintstatus;
 	spinlock_t sleeplock;
 	int wakeupreason;
@@ -45,6 +44,7 @@ typedef struct thread_t {
 	void *kernelarg;
 	context_t *usercopyctx;
 	int class;
+	int nice;
 	struct {
 		spinlock_t lock;
 		eventheader_t waitpendingevent;
@@ -67,7 +67,7 @@ typedef struct thread_t {
 } thread_t;
 
 __attribute__((noreturn)) void sched_threadexit();
-thread_t *sched_newthread(void *ip, size_t kstacksize, int priority, struct proc_t *proc, void *ustack);
+thread_t *sched_newthread(void *ip, size_t kstacksize, int nice, struct proc_t *proc, void *ustack);
 void sched_destroythread(thread_t *);
 
 #endif

kernel-src/sys/defaultauth.c

@@ -264,6 +264,13 @@ static int process(cred_t *cred, int actions, void *arg0, void *arg1, void *arg2
 		DONE_CHECK(actions);
 	}
 
+	if (actions & AUTH_ACTIONS_PROCESS_NICE) {
+		if (CRED_IS_ESU(cred))
+			weight += 1;
+
+		DONE_CHECK(actions);
+	}
+
 	done:
 	return weight ? AUTH_DECISION_ALLOW : AUTH_DECISION_DEFER;
 }

kernel-src/sys/scheduler/metrics.c

@@ -11,11 +11,12 @@ static void update_interactivity(thread_t *thread) {
 	time_t run_time = thread->metrics.run_time_avg_us;
 
 	if (sleep_time > run_time)
-		thread->metrics.interactivity_score = min((SCALING_FACTOR * run_time) / sleep_time, SCHED_MAX_INTERACTIVITY);
+		thread->metrics.interactivity_score = (SCALING_FACTOR * run_time) / sleep_time;
 	else
-		thread->metrics.interactivity_score = min((SCALING_FACTOR * sleep_time) / run_time + SCALING_FACTOR, SCHED_MAX_INTERACTIVITY);
+		thread->metrics.interactivity_score = (SCALING_FACTOR * sleep_time) / run_time + SCALING_FACTOR;
 
-	// TODO nice value impacting this 
+	thread->metrics.interactivity_score += thread->nice + (thread->proc ? thread->proc->nice : 0);
+	thread->metrics.interactivity_score = min(thread->metrics.interactivity_score, SCHED_MAX_INTERACTIVITY);
 }
 
 static void offset_times(thread_t *thread, time_t run_us, time_t sleep_us) {

kernel-src/sys/scheduler/scheduler.c

@@ -310,15 +310,10 @@ void sched_reschedule_on_cpu(cpu_t *cpu, bool target) {
 	if (cpu == current_cpu())
 		goto leave;
 
-	long old_priority = current_thread()->priority;
-	current_thread()->priority = 0;
-
 	sched_thread_stopping_callback(current_thread(), false);
 
 	arch_context_saveandcall(reschedule_yield, current_cpu()->schedulerstack, cpu);
 
-	current_thread()->priority = old_priority;
-
 	leave:
 	interrupt_set(status);
 	if (target == false)
@@ -354,7 +349,7 @@ void sched_ap_entry() {
 	__assert(current_cpu()->schedulerstack);
 	current_cpu()->schedulerstack = (void *)((uintptr_t)current_cpu()->schedulerstack + SCHEDULER_STACK_SIZE);
 
-	current_cpu()->idlethread = sched_newthread(cpuidlethread, PAGE_SIZE * 4, 3, NULL, NULL);
+	current_cpu()->idlethread = sched_newthread(cpuidlethread, PAGE_SIZE * 4, 100, NULL, NULL);
 	__assert(current_cpu()->idlethread);
 	current_cpu()->idlethread->class = THREAD_CLASS_IDLE;
 	sched_queue(current_cpu()->idlethread);
@@ -382,7 +377,7 @@ void sched_init() {
 	__assert(current_cpu()->schedulerstack);
 	current_cpu()->schedulerstack = (void *)((uintptr_t)current_cpu()->schedulerstack + SCHEDULER_STACK_SIZE);
 
-	current_cpu()->idlethread = sched_newthread(cpuidlethread, PAGE_SIZE * 4, 3, NULL, NULL);
+	current_cpu()->idlethread = sched_newthread(cpuidlethread, PAGE_SIZE * 4, 100, NULL, NULL);
 	__assert(current_cpu()->idlethread);
 	current_cpu()->idlethread->class = THREAD_CLASS_IDLE;
 	current_cpu()->thread = sched_newthread(NULL, PAGE_SIZE * 32, 0, NULL, NULL);

kernel-src/sys/syscalls/nice.c

@@ -0,0 +1,17 @@
+#include <kernel/syscalls.h>
+#include <kernel/thread.h>
+#include <arch/cpu.h>
+
+syscallret_t syscall_nice(context_t *, int nice) {
+	syscallret_t ret;
+
+
+	if (nice < 0) {
+		
+	}
+
+	current_thread()->proc->nice = max(min(current_thread()->proc->nice + nice, SCHED_NICE_MAX), SCHED_NICE_MIN);
+
+	ret.ret = current_thread()->proc->nice;
+	return ret;
+}

kernel-src/sys/thread.c

@@ -5,7 +5,7 @@
 
 static scache_t *thread_cache;
 
-thread_t *sched_newthread(void *ip, size_t kstacksize, int priority, proc_t *proc, void *ustack) {
+thread_t *sched_newthread(void *ip, size_t kstacksize, int nice, proc_t *proc, void *ustack) {
 	if (thread_cache == NULL) {
 		thread_cache = slab_newcache(sizeof(thread_t), 0, NULL, NULL);
 		__assert(thread_cache);
@@ -28,8 +28,8 @@ thread_t *sched_newthread(void *ip, size_t kstacksize, int priority, proc_t *pro
 	// non kernel thread vmm contexts are handled by the caller
 	thread->vmmctx = proc ? NULL : &vmm_kernelctx;
 	thread->proc = proc;
-	thread->priority = priority;
 	thread->kernelstacksize = kstacksize;
+	thread->nice = nice;
 	if (proc) {
 		// each thread holds one reference to proc
 		PROC_HOLD(proc);