From 95833311f10ec7c23d9c550213909aa2e35bd1b6 Mon Sep 17 00:00:00 2001
From: Jason Evans <je@facebook.com>
Date: Wed, 27 Jan 2010 13:45:21 -0800
Subject: [PATCH] madvise(..., MADV_{RANODOM,NOSYNC}) swap files.

Initialize malloc before calling into the ctl_*() functions.
---
 jemalloc/src/jemalloc.c            |  9 +++++++++
 jemalloc/src/jemalloc_chunk_swap.c | 13 +++++++++++++
 2 files changed, 22 insertions(+)

diff --git a/jemalloc/src/jemalloc.c b/jemalloc/src/jemalloc.c
index b807a22d..9f71c016 100644
--- a/jemalloc/src/jemalloc.c
+++ b/jemalloc/src/jemalloc.c
@@ -1246,6 +1246,9 @@ JEMALLOC_P(mallctl)(const char *name, void *oldp, size_t *oldlenp, void *newp,
     size_t newlen)
 {
 
+	if (malloc_init())
+		return (EAGAIN);
+
 	return (ctl_byname(name, oldp, oldlenp, newp, newlen));
 }
 
@@ -1254,6 +1257,9 @@ int
 JEMALLOC_P(mallctlnametomib)(const char *name, size_t *mibp, size_t *miblenp)
 {
 
+	if (malloc_init())
+		return (EAGAIN);
+
 	return (ctl_nametomib(name, mibp, miblenp));
 }
 
@@ -1263,6 +1269,9 @@ JEMALLOC_P(mallctlbymib)(const size_t *mib, size_t miblen, void *oldp,
     size_t *oldlenp, void *newp, size_t newlen)
 {
 
+	if (malloc_init())
+		return (EAGAIN);
+
 	return (ctl_bymib(mib, miblen, oldp, oldlenp, newp, newlen));
 }
 
diff --git a/jemalloc/src/jemalloc_chunk_swap.c b/jemalloc/src/jemalloc_chunk_swap.c
index fa5a5b14..c185d431 100644
--- a/jemalloc/src/jemalloc_chunk_swap.c
+++ b/jemalloc/src/jemalloc_chunk_swap.c
@@ -311,6 +311,19 @@ chunk_swap_enable(const int *fds, unsigned nfds, bool prezeroed)
 			goto RETURN;
 		}
 		assert(addr == (void *)((uintptr_t)vaddr + voff));
+
+		/*
+		 * Tell the kernel that the mapping will be accessed randomly,
+		 * and that it should not gratuitously sync pages to the
+		 * filesystem.
+		 */
+#ifdef MADV_RANDOM
+		madvise(addr, sizes[i], MADV_RANDOM);
+#endif
+#ifdef MADV_NOSYNC
+		madvise(addr, sizes[i], MADV_NOSYNC);
+#endif
+
 		voff += sizes[i];
 	}