Changeset b4ad39f in mainline

Timestamp:

2010-04-26T22:23:16Z (15 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

b8f7ea78

Parents:

aeb6f25

Message:

Do not hold the sysinfo spinlock either when doing copy_from_uspace().

File:

• kernel/generic/src/sysinfo/sysinfo.c (modified) (7 diffs)

kernel/generic/src/sysinfo/sysinfo.c

@@ -632 +632 @@
 /** Return sysinfo item determined by name from user space
  *
- * Should be called with interrupts disabled
- * and sysinfo_lock held. The path string passed from
- * the user space has to be properly null-terminated
+ * The path string passed from the user space has to be properly null-terminated
  * (the last passed character must be null).
  *
@@ -656 +654 @@
         
         if ((copy_from_uspace(path, ptr, size + 1) == 0)
-            && (path[size] == 0))
+            && (path[size] == 0)) {
+                /*
+                 * Prevent other functions from messing with sysinfo while we
+                 * are reading it.
+                 */
+                ipl_t ipl = interrupts_disable();
+                spinlock_lock(&sysinfo_lock);
                 ret = sysinfo_get_item(path, NULL, dry_run);
-        
+                spinlock_unlock(&sysinfo_lock);
+                interrupts_restore(ipl);
+        }
         free(path);
         return ret;
@@ -677 +683 @@
 unative_t sys_sysinfo_get_tag(void *path_ptr, size_t path_size)
 {
-        /* Avoid other functions to mess with sysinfo
-           while we are reading it */
-        ipl_t ipl = interrupts_disable();
-        spinlock_lock(&sysinfo_lock);
-        
-        /* Get the item.
-        
-           N.B.: There is no need to free any potential generated
-           binary data since we request a dry run */
+        /*
+         * Get the item.
+         *
+         * N.B.: There is no need to free any potential generated
+         * binary data since we request a dry run.
+         */
         sysinfo_return_t ret = sysinfo_get_item_uspace(path_ptr, path_size, true);
         
-        /* Map generated value types to constant types
-           (user space does not care whether the
-           value is constant or generated) */
+        /*
+         * Map generated value types to constant types (user space does not care
+         * whether the value is constant or generated).
+         */
         if (ret.tag == SYSINFO_VAL_FUNCTION_VAL)
                 ret.tag = SYSINFO_VAL_VAL;
@@ -696 +700 @@
                 ret.tag = SYSINFO_VAL_DATA;
         
-        spinlock_unlock(&sysinfo_lock);
-        interrupts_restore(ipl);
-        
         return (unative_t) ret.tag;
 }
@@ -719 +720 @@
     void *value_ptr)
 {
-        /* Avoid other functions to mess with sysinfo
-           while we are reading it */
-        ipl_t ipl = interrupts_disable();
-        spinlock_lock(&sysinfo_lock);
-        
-        /* Get the item.
-        
-           N.B.: There is no need to free any potential generated
-           binary data since we request a dry run */
+        int rc;
+
+        /*
+         * Get the item.
+         *
+         * N.B.: There is no need to free any potential generated binary data
+         * since we request a dry run.
+         */
         sysinfo_return_t ret = sysinfo_get_item_uspace(path_ptr, path_size, true);
-
-        spinlock_unlock(&sysinfo_lock);
-        interrupts_restore(ipl);
-        
-        int rc;
         
         /* Only constant or generated numerical value is returned */
@@ -761 +756 @@
     void *size_ptr)
 {
-        /* Avoid other functions to mess with sysinfo
-           while we are reading it */
-        ipl_t ipl = interrupts_disable();
-        spinlock_lock(&sysinfo_lock);
-        
-        /* Get the item.
-        
-           N.B.: There is no need to free any potential generated
-           binary data since we request a dry run */
+        int rc;
+        
+        /*
+         * Get the item.
+         *
+         * N.B.: There is no need to free any potential generated binary data
+         * since we request a dry run.
+         */
         sysinfo_return_t ret = sysinfo_get_item_uspace(path_ptr, path_size, true);
-
-        spinlock_unlock(&sysinfo_lock);
-        interrupts_restore(ipl);
-        
-        int rc;
         
         /* Only the size of constant or generated binary data is considered */
@@ -809 +798 @@
     void *buffer_ptr, size_t buffer_size)
 {
-        /* Avoid other functions to mess with sysinfo
-           while we are reading it */
-        ipl_t ipl = interrupts_disable();
-        spinlock_lock(&sysinfo_lock);
+        int rc;
         
         /* Get the item */
         sysinfo_return_t ret = sysinfo_get_item_uspace(path_ptr, path_size, false);
 
-        spinlock_unlock(&sysinfo_lock);
-        interrupts_restore(ipl);
-
-        int rc;
-        
         /* Only constant or generated binary data is considered */
         if ((ret.tag == SYSINFO_VAL_DATA) || (ret.tag == SYSINFO_VAL_FUNCTION_DATA)) {