From: Matthias Kruk <m@m10k.eu>
Date: Thu, 2 Jan 2020 07:39:45 +0000 (+0900)
Subject: Make a thread execute the signal handler itself if it is delivering a signal to the... 
X-Git-Url: https://git.corax.cc/?a=commitdiff_plain;h=917345a3c2eefa73130233667f2b860772614c62;p=corax

Make a thread execute the signal handler itself if it is delivering a signal to the current process (instead of going through the trouble of electing a handling task)
---

diff --git a/kernel/core/process.c b/kernel/core/process.c
index 7d45a27..23335e2 100644
--- a/kernel/core/process.c
+++ b/kernel/core/process.c
@@ -9,6 +9,7 @@
 #include <signal.h>
 #include <string.h>
 #include <spinlock.h>
+#include <unistd.h>
 #include "fd.h"
 #include "sched.h"
 
@@ -496,6 +497,7 @@ int process_memcpy_ktop(process_t *proc, void *dst, void *src, u32_t bytes)
 {
 	int ret_val;
 
+	dbg_printf("pg_dir_memcpy(%p, %p, NULL, %p, 0x%08x)\n", proc, dst, src, bytes);
 	ret_val = pg_dir_memcpy(proc->p_pgdir, dst, NULL, src, bytes);
 
 	return(ret_val);
@@ -734,25 +736,33 @@ int process_signal_deliver(process_t *proc, int signal)
 	ret_val = -EINVAL;
 
 	if(proc && signal > 0 && signal <= SIGUNUSED) {
+		process_t *cproc;
 		stack_frame_t *kstk;
 		u32_t *vesp3;
 		u32_t *pesp3;
 		task_t *task;
 		int i;
 
-		/* FIXME: Need to suspend the process in order to deliver the signal safely */
-		process_suspend(proc);
+		cproc = process_get_current();
 
-		/*
-		 * Elect a task to handle the signal - right now, this is simple since the
-		 * implementation doesn't support more than one task per process, and we
-		 * can just pick the first (and only) one.
-		 */
-		for(task = NULL, i = 0; i < CONFIG_PROC_MAXTASKS; i++) {
-			if(proc->p_tasks[i]) {
-				task = proc->p_tasks[i];
-				break;
+		if(cproc != proc) {
+			/* FIXME: Need to suspend the process in order to deliver the signal safely */
+			process_suspend(proc);
+
+			/*
+			 * Elect a task to handle the signal - right now, this is simple since the
+			 * implementation doesn't support more than one task per process, and we
+			 * can just pick the first (and only) one.
+			 */
+			for(task = NULL, i = 0; i < CONFIG_PROC_MAXTASKS; i++) {
+				if(proc->p_tasks[i]) {
+					task = proc->p_tasks[i];
+					break;
+				}
 			}
+		} else {
+			/* handle the signal in the current task */
+			task = task_get_current();
 		}
 
 		if(!task) {
@@ -838,14 +848,16 @@ cleanup:
 	return(ret_val);
 }
 
+/*
+ * FIXME: Don't call kernel code from _sig_* functions
+ *
+ * The _sig_* functions will be executed in user-mode after the
+ * process has returned from kernel-mode via iret. Kernel-mode
+ * code will have to be called through the usual syscall interface.
+ */
 static void _sig_term(int sig)
 {
-	process_t *cproc;
-
-	cproc = process_get_current();
-
-	/* FIXME: terminate the process */
-
+	_exit(sig);
 	return;
 }
 
@@ -857,21 +869,12 @@ static void _sig_ign(int sig)
 
 static void _sig_core(int sig)
 {
-	process_t *cproc;
-
-	cproc = process_get_current();
-
-	/* FIXME: terminate process and generate a core dump */
-
+	_exit(sig);
 	return;
 }
 
 static void _sig_stop(int sig)
 {
-	process_t *cproc;
-
-	cproc = process_get_current();
-
 	/*
 	 * FIXME: Stop the process
 	 *  - Change the process state
@@ -881,16 +884,11 @@ static void _sig_stop(int sig)
 	 *
 	 * Or better yet, make it wait on a lock in the stop handler.
 	 */
-
 	return;
 }
 
 static void _sig_cont(int sig)
 {
-	process_t *cproc;
-
-	cproc = process_get_current();
-
 	/*
 	 * FIXME: Continue the process
 	 *  - Change its state back to a runnable state