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serial/core.c: Unneeded memory barriers and cleanup

PATCH New Felipe W Damasio 1 participant 1 message Sep 15, 2003

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Felipe W Damasio

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PATCH 1/1 serial/core.c: Unneeded memory barriers and cleanup

Hi Russell,

Patch against 2.6-test5.

Kills a unneeded set_current_state (TASK_RUNNING) after
schedule_timeout and replaces a TASK_RUNNING settings with non-memory-barrier versions.

On uart_suspend_port, that set state thing isn't needed if
schedule_timeout was executed..but I couldn't come up with a (clean) fix for that, since we need to execute ops->shutdown. So I just replace it with __set_current_state so It's just an attribution and it's not that expensive.

Feel free to tell me I screwed up :)

Thanks,

Felipe

serial/core.c renamed from serial/core.c.orig +6 -7
@@ -1022,7 +1022,7 @@
 		cprev = cnow;
 	}
 
-	current->state = TASK_RUNNING;
+	__set_current_state(TASK_RUNNING);
 	remove_wait_queue(&state->info->delta_msr_wait, &wait);
 
 	return ret;

@@ -1277,7 +1277,6 @@
 		if (state->close_delay) {
 			set_current_state(TASK_INTERRUPTIBLE);
 			schedule_timeout(state->close_delay);
-			set_current_state(TASK_RUNNING);
 		}
 	} else if (!uart_console(port)) {
 		uart_change_pm(state, 3);

@@ -1345,11 +1344,11 @@
 		set_current_state(TASK_INTERRUPTIBLE);
 		schedule_timeout(char_time);
 		if (signal_pending(current))
-			break;
+			return;
 		if (time_after(jiffies, expire))
-			break;
+			return;
 	}
-	set_current_state(TASK_RUNNING); /* might not be needed */
+	__set_current_state(TASK_RUNNING); /* might not be needed */
 }
 
 /*

@@ -1480,7 +1479,7 @@
 		if (signal_pending(current))
 			break;
 	}
-	set_current_state(TASK_RUNNING);
+	__set_current_state(TASK_RUNNING);
 	remove_wait_queue(&info->open_wait, &wait);
 
 	state->count++;

@@ -1899,7 +1898,7 @@
 				set_current_state(TASK_UNINTERRUPTIBLE);
 				schedule_timeout(10*HZ/1000);
 			}
-			set_current_state(TASK_RUNNING);
+			__set_current_state(TASK_RUNNING);
 
 			ops->shutdown(port);
 		}