From: Tom Keiser <tkeiser@sinenomine.net>
Date: Tue, 10 Apr 2012 20:26:42 +0000 (-0400)
Subject: libafs: use kthread_run when available
X-Git-Tag: openafs-stable-1_8_0pre1~2096
X-Git-Url: https://git.openafs.org/?p=openafs.git;a=commitdiff_plain;h=b440d8ffcbb0ac58ecaa34a9c60fe27a0fc91026

libafs: use kthread_run when available

Use the kthread_run interface on linux to create kernel
threads.  This interface allows all the cpus to schedule
afsd threads, instead of just inheriting the cpu affinity of
the main afsd thread.

Written by Tom Keiser.

Change-Id: I69eb852d168bd85e9aa7ec075013c0346207dbcf
Reviewed-on: http://gerrit.openafs.org/7915
Reviewed-by: Derrick Brashear <shadow@dementix.org>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
---

diff --git a/acinclude.m4 b/acinclude.m4
index 7f69dad..3855509 100644
--- a/acinclude.m4
+++ b/acinclude.m4
@@ -921,6 +921,10 @@ case $AFS_SYSNAME in *_linux* | *_umlinux*)
 		 AC_CHECK_LINUX_FUNC([noop_fsync],
 				     [#include <linux/fs.h>],
 				     [void *address = &noop_fsync; printk("%p\n", address)];)
+		 AC_CHECK_LINUX_FUNC([kthread_run],
+				     [#include <linux/kernel.h>
+				      #include <linux/kthread.h>],
+				     [kthread_run(NULL, NULL, "test");])
 
 		 dnl Consequences - things which get set as a result of the
 		 dnl                above tests
diff --git a/src/afs/afs_call.c b/src/afs/afs_call.c
index 858dc5c..aebc567 100644
--- a/src/afs/afs_call.c
+++ b/src/afs/afs_call.c
@@ -15,14 +15,19 @@
 #include "afsincludes.h"	/* Afs-based standard headers */
 #include "afs/afs_stats.h"
 #include "rx/rx_globals.h"
-#if !defined(UKERNEL) && !defined(AFS_LINUX20_ENV)
-#include "net/if.h"
-#ifdef AFS_SGI62_ENV
-#include "h/hashing.h"
-#endif
-#if !defined(AFS_HPUX110_ENV) && !defined(AFS_DARWIN_ENV)
-#include "netinet/in_var.h"
-#endif
+#if !defined(UKERNEL)
+# if !defined(AFS_LINUX20_ENV)
+#  include "net/if.h"
+#  ifdef AFS_SGI62_ENV
+#   include "h/hashing.h"
+#  endif
+#  if !defined(AFS_HPUX110_ENV) && !defined(AFS_DARWIN_ENV)
+#   include "netinet/in_var.h"
+#  endif
+# endif
+# ifdef HAVE_LINUX_KTHREAD_RUN
+#  include "h/kthread.h"
+# endif
 #endif /* !defined(UKERNEL) */
 #ifdef AFS_SUN510_ENV
 #include "h/ksynch.h"
@@ -292,11 +297,13 @@ afsd_thread(void *rock)
 # ifdef SYS_SETPRIORITY_EXPORTED
     int (*sys_setpriority) (int, int, int) = sys_call_table[__NR_setpriority];
 # endif
-# if defined(AFS_LINUX26_ENV)
+# if !defined(HAVE_LINUX_KTHREAD_RUN)
+#  if defined(AFS_LINUX26_ENV)
     daemonize("afsd");
-# else
+#  else
     daemonize();
-# endif
+#  endif
+# endif /* !HAVE_LINUX_KTHREAD_RUN */
 				/* doesn't do much, since we were forked from keventd, but
 				 * does call mm_release, which wakes up our parent (since it
 				 * used CLONE_VFORK) */
@@ -433,8 +440,14 @@ afsd_launcher(void *rock)
     struct afsd_thread_info *rock = container_of(work, struct afsd_thread_info, tq);
 # endif
 
+# if defined(HAVE_LINUX_KTHREAD_RUN)
+    if (IS_ERR(kthread_run(afsd_thread, (void *)rock, "afsd"))) {
+	afs_warn("kthread_run failed; afs startup will not complete\n");
+    }
+# else /* !HAVE_LINUX_KTHREAD_RUN */
     if (!kernel_thread(afsd_thread, (void *)rock, CLONE_VFORK | SIGCHLD))
 	afs_warn("kernel_thread failed. afs startup will not complete\n");
+# endif /* !HAVE_LINUX_KTHREAD_RUN */
 }
 
 void