[rds-commits] zab commits r184 - trunk/linux/net/rds

[svn-commits at oss.oracle.com]

Author: zab
Date: 2007-01-19 12:10:36 -0800 (Fri, 19 Jan 2007)
New Revision: 184

Modified:
   trunk/linux/net/rds/ib.h
   trunk/linux/net/rds/page.c
Log:
Disable interrupts while working with the per-cpu page remainder data.

The rx path allocates acks with the page remainder allocator and so can swoop
in mess with the per-cpu data structures under the paths which are allocating
form user context.  It pinned the user path to a cpu and disabled pre-emption,
but forgot to disable interrupts.


Modified: trunk/linux/net/rds/ib.h
===================================================================
--- trunk/linux/net/rds/ib.h	2007-01-11 21:20:12 UTC (rev 183)
+++ trunk/linux/net/rds/ib.h	2007-01-19 20:10:36 UTC (rev 184)
@@ -1,6 +1,8 @@
 #ifndef _RDS_IB_H
 #define _RDS_IB_H 
 
+#include <linux/mutex.h>
+
 #include <rdma/ib_verbs.h>
 #include <rdma/rdma_cm.h>
 #include "rds.h"

Modified: trunk/linux/net/rds/page.c
===================================================================
--- trunk/linux/net/rds/page.c	2007-01-11 21:20:12 UTC (rev 183)
+++ trunk/linux/net/rds/page.c	2007-01-19 20:10:36 UTC (rev 184)
@@ -87,6 +87,7 @@
 			     gfp_t gfp)
 {
 	struct rds_page_remainder *rem;
+	unsigned long flags;
 	struct page *page;
 	int ret;
 
@@ -107,6 +108,7 @@
 	}
 
 	rem = &rds_per_cpu(rds_page_remainders, get_cpu());
+	local_irq_save(flags);
 
 	for(;;) {
 		/* avoid a tiny region getting stuck by tossing it */
@@ -136,9 +138,13 @@
 		}
 
 		/* alloc if there is nothing for us to use */
+		local_irq_restore(flags);
 		put_cpu();
+
 		page = alloc_page(gfp);
+
 		rem = &rds_per_cpu(rds_page_remainders, get_cpu());
+		local_irq_save(flags);
 
 		if (page == NULL) {
 			ret = -ENOMEM;
@@ -156,6 +162,7 @@
 		rem->r_offset = 0;
 	}
 
+	local_irq_restore(flags);
 	put_cpu();
 out:
 	rdsdebug("bytes %lu ret %d %p %u %u\n", bytes, ret,