- (dtucker) [openbsd-compat/port-linux.c] Bug #1838: Add support for the new

   Linux OOM-killer magic values that changed in 2.6.36 kernels, with fallback
   to the old values.  Feedback from vapier at gentoo org and djm, ok djm.

1 files changed, 36 insertions, 19 deletions

diff --git a/openbsd-compat/port-linux.c b/openbsd-compat/port-linux.c
index 86d16dc6e..d89101d18 100644
--- a/openbsd-compat/port-linux.c
+++ b/openbsd-compat/port-linux.c
@@ -1,4 +1,4 @@
-/* $Id: port-linux.c,v 1.9 2010/09/10 00:30:25 dtucker Exp $ */
+/* $Id: port-linux.c,v 1.10 2011/01/17 00:56:00 dtucker Exp $ */
 
 /*
  * Copyright (c) 2005 Daniel Walsh <dwalsh@redhat.com>
@@ -208,14 +208,22 @@ ssh_selinux_change_context(const char *newname)
 #endif /* WITH_SELINUX */
 
 #ifdef LINUX_OOM_ADJUST
-#define OOM_ADJ_PATH    "/proc/self/oom_adj"
 /*
- * The magic "don't kill me", as documented in eg:
+ * The magic "don't kill me" values, old and new, as documented in eg:
  * http://lxr.linux.no/#linux+v2.6.32/Documentation/filesystems/proc.txt
+ * http://lxr.linux.no/#linux+v2.6.36/Documentation/filesystems/proc.txt
  */
-#define OOM_ADJ_NOKILL  -17
 
 static int oom_adj_save = INT_MIN;
+static char *oom_adj_path = NULL;
+struct {
+        char *path;
+        int value;
+} oom_adjust[] = {
+        {"/proc/self/oom_score_adj", -1000},    /* kernels >= 2.6.36 */
+        {"/proc/self/oom_adj", -17},            /* kernels <= 2.6.35 */
+        {NULL, 0},
+};
 
 /*
  * Tell the kernel's out-of-memory killer to avoid sshd.
@@ -224,23 +232,31 @@ static int oom_adj_save = INT_MIN;
 void
 oom_adjust_setup(void)
 {
+        int i, value;
         FILE *fp;
 
         debug3("%s", __func__);
-        if ((fp = fopen(OOM_ADJ_PATH, "r+")) != NULL) {
-                if (fscanf(fp, "%d", &oom_adj_save) != 1)
-                        verbose("error reading %s: %s", OOM_ADJ_PATH, strerror(errno));
-                else {
-                        rewind(fp);
-                        if (fprintf(fp, "%d\n", OOM_ADJ_NOKILL) <= 0)
-                                verbose("error writing %s: %s",
-                                    OOM_ADJ_PATH, strerror(errno));
-                        else
-                                verbose("Set %s from %d to %d",
-                                    OOM_ADJ_PATH, oom_adj_save, OOM_ADJ_NOKILL);
+         for (i = 0; oom_adjust[i].path != NULL; i++) {
+                oom_adj_path = oom_adjust[i].path;
+                value = oom_adjust[i].value;
+                if ((fp = fopen(oom_adj_path, "r+")) != NULL) {
+                        if (fscanf(fp, "%d", &oom_adj_save) != 1)
+                                verbose("error reading %s: %s", oom_adj_path,
+                                    strerror(errno));
+                        else {
+                                rewind(fp);
+                                if (fprintf(fp, "%d\n", value) <= 0)
+                                        verbose("error writing %s: %s",
+                                           oom_adj_path, strerror(errno));
+                                else
+                                        verbose("Set %s from %d to %d",
+                                           oom_adj_path, oom_adj_save, value);
+                        }
+                        fclose(fp);
+                        return;
                 }
-                fclose(fp);
         }
+        oom_adj_path = NULL;
 }
 
 /* Restore the saved OOM adjustment */
@@ -250,13 +266,14 @@ oom_adjust_restore(void)
         FILE *fp;
 
         debug3("%s", __func__);
-        if (oom_adj_save == INT_MIN || (fp = fopen(OOM_ADJ_PATH, "w")) == NULL)
+        if (oom_adj_save == INT_MIN || oom_adj_save == NULL ||
+            (fp = fopen(oom_adj_path, "w")) == NULL)
                 return;
 
         if (fprintf(fp, "%d\n", oom_adj_save) <= 0)
-                verbose("error writing %s: %s", OOM_ADJ_PATH, strerror(errno));
+                verbose("error writing %s: %s", oom_adj_path, strerror(errno));
         else
-                verbose("Set %s to %d", OOM_ADJ_PATH, oom_adj_save);
+                verbose("Set %s to %d", oom_adj_path, oom_adj_save);
 
         fclose(fp);
         return;