From 666c5bf7a8baaa842da69cb402948411432a9d00 Mon Sep 17 00:00:00 2001
From: Mike Hommey <mh@glandium.org>
Date: Wed, 18 Apr 2012 18:29:43 +0200
Subject: [PATCH] Add a pages_purge function to wrap
 madvise(JEMALLOC_MADV_PURGE) calls

This will be used to implement the feature on mingw, which doesn't have
madvise.
---
 include/jemalloc/internal/chunk_mmap.h        |  2 ++
 include/jemalloc/internal/private_namespace.h |  1 +
 include/jemalloc/jemalloc_defs.h.in           |  7 -------
 src/arena.c                                   |  4 ++--
 src/chunk.c                                   |  2 +-
 src/chunk_mmap.c                              | 14 ++++++++++++++
 6 files changed, 20 insertions(+), 10 deletions(-)

diff --git a/include/jemalloc/internal/chunk_mmap.h b/include/jemalloc/internal/chunk_mmap.h
index 04e86af9..2d01ac22 100644
--- a/include/jemalloc/internal/chunk_mmap.h
+++ b/include/jemalloc/internal/chunk_mmap.h
@@ -9,6 +9,8 @@
 /******************************************************************************/
 #ifdef JEMALLOC_H_EXTERNS
 
+void	pages_purge(void *addr, size_t length);
+
 void	*chunk_alloc_mmap(size_t size, size_t alignment);
 bool	chunk_dealloc_mmap(void *chunk, size_t size);
 
diff --git a/include/jemalloc/internal/private_namespace.h b/include/jemalloc/internal/private_namespace.h
index a69482b6..a2171ed2 100644
--- a/include/jemalloc/internal/private_namespace.h
+++ b/include/jemalloc/internal/private_namespace.h
@@ -196,6 +196,7 @@
 #define	opt_xmalloc JEMALLOC_N(opt_xmalloc)
 #define	opt_zero JEMALLOC_N(opt_zero)
 #define	p2rz JEMALLOC_N(p2rz)
+#define	pages_purge JEMALLOC_N(pages_purge)
 #define	pow2_ceil JEMALLOC_N(pow2_ceil)
 #define	prof_backtrace JEMALLOC_N(prof_backtrace)
 #define	prof_boot0 JEMALLOC_N(prof_boot0)
diff --git a/include/jemalloc/jemalloc_defs.h.in b/include/jemalloc/jemalloc_defs.h.in
index 90baa355..6e816557 100644
--- a/include/jemalloc/jemalloc_defs.h.in
+++ b/include/jemalloc/jemalloc_defs.h.in
@@ -220,13 +220,6 @@
  */
 #undef JEMALLOC_PURGE_MADVISE_DONTNEED
 #undef JEMALLOC_PURGE_MADVISE_FREE
-#ifdef JEMALLOC_PURGE_MADVISE_DONTNEED
-#  define JEMALLOC_MADV_PURGE MADV_DONTNEED
-#elif defined(JEMALLOC_PURGE_MADVISE_FREE)
-#  define JEMALLOC_MADV_PURGE MADV_FREE
-#else
-#  error "No method defined for purging unused dirty pages."
-#endif
 
 /* sizeof(void *) == 2^LG_SIZEOF_PTR. */
 #undef LG_SIZEOF_PTR
diff --git a/src/arena.c b/src/arena.c
index 0f15562a..ed47824a 100644
--- a/src/arena.c
+++ b/src/arena.c
@@ -676,8 +676,8 @@ arena_chunk_purge(arena_t *arena, arena_chunk_t *chunk)
 		if (config_debug)
 			ndirty -= npages;
 
-		madvise((void *)((uintptr_t)chunk + (pageind << LG_PAGE)),
-		    (npages << LG_PAGE), JEMALLOC_MADV_PURGE);
+		pages_purge((void *)((uintptr_t)chunk + (pageind << LG_PAGE)),
+		    (npages << LG_PAGE));
 		if (config_stats)
 			nmadvise++;
 	}
diff --git a/src/chunk.c b/src/chunk.c
index 67e0d503..bcaedea4 100644
--- a/src/chunk.c
+++ b/src/chunk.c
@@ -171,7 +171,7 @@ chunk_record(void *chunk, size_t size)
 {
 	extent_node_t *xnode, *node, *prev, key;
 
-	madvise(chunk, size, JEMALLOC_MADV_PURGE);
+	pages_purge(chunk, size);
 
 	xnode = NULL;
 	malloc_mutex_lock(&chunks_mtx);
diff --git a/src/chunk_mmap.c b/src/chunk_mmap.c
index e11cc0e6..9dea8318 100644
--- a/src/chunk_mmap.c
+++ b/src/chunk_mmap.c
@@ -72,6 +72,20 @@ pages_unmap(void *addr, size_t size)
 	}
 }
 
+void
+pages_purge(void *addr, size_t length)
+{
+
+#ifdef JEMALLOC_PURGE_MADVISE_DONTNEED
+#  define JEMALLOC_MADV_PURGE MADV_DONTNEED
+#elif defined(JEMALLOC_PURGE_MADVISE_FREE)
+#  define JEMALLOC_MADV_PURGE MADV_FREE
+#else
+#  error "No method defined for purging unused dirty pages."
+#endif
+	madvise(addr, length, JEMALLOC_MADV_PURGE);
+}
+
 static void *
 chunk_alloc_mmap_slow(size_t size, size_t alignment, bool unaligned)
 {