On Fri 23-09-16 16:29:36, Hillf Danton wrote:
[...]

quoted

@@ -3659,6 +3661,15 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order,
 	else
 		no_progress_loops++;

+	/* Make sure we know about allocations which stall for too long */
+	if (!(gfp_mask & __GFP_NOWARN) && time_after(jiffies, alloc_start + stall_timeout)) {
+		pr_warn("%s: page alloction stalls for %ums: order:%u mode:%#x(%pGg)\n",
+				current->comm, jiffies_to_msecs(jiffies-alloc_start),

Better if pid is also printed.

I've tried to be consistent with warn_alloc_failed and that doesn't
print pid either. Maybe both of them should. Dunno

quoted

+				order, gfp_mask, &gfp_mask);
+		stall_timeout += 10 * HZ;

Alternatively	 alloc_start = jiffies;

Then we would lose the cumulative time in the output which is imho
helpful because you cannot tell whether the new warning is a new request
or the old one still looping.

quoted

+		dump_stack();
+	}
+
 	if (should_reclaim_retry(gfp_mask, order, ac, alloc_flags,
 				 did_some_progress > 0, no_progress_loops))
 		goto retry;
--
2.9.3

thanks
Hillf

-- 
Michal Hocko
SUSE Labs

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>