[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Qemu-stable] [PATCH stable-0.15 36/36] qemu_vmalloc: align properly for
From: |
Andreas Färber |
Subject: |
[Qemu-stable] [PATCH stable-0.15 36/36] qemu_vmalloc: align properly for transparent hugepages and KVM |
Date: |
Wed, 28 Mar 2012 14:52:39 +0200 |
From: Avi Kivity <address@hidden>
To make good use of transparent hugepages, KVM requires that guest-physical
and host-virtual addresses share the low 21 bits (as opposed to just the low
12 bits normally required).
Adjust qemu_vmalloc() to honor that requirement. Ignore it for small regions
to avoid fragmentation.
Signed-off-by: Avi Kivity <address@hidden>
Signed-off-by: Anthony Liguori <address@hidden>
(cherry picked from commit 36b586284e678da28df3af9fd0907d2b16f9311c)
Signed-off-by: Bruce Rogers <address@hidden>
Signed-off-by: Andreas Färber <address@hidden>
---
oslib-posix.c | 14 +++++++++++++-
1 files changed, 13 insertions(+), 1 deletions(-)
diff --git a/oslib-posix.c b/oslib-posix.c
index 196099c..a304fb0 100644
--- a/oslib-posix.c
+++ b/oslib-posix.c
@@ -35,6 +35,13 @@
extern int daemon(int, int);
#endif
+#if defined(__linux__) && defined(__x86_64__)
+ /* Use 2MB alignment so transparent hugepages can be used by KVM */
+# define QEMU_VMALLOC_ALIGN (512 * 4096)
+#else
+# define QEMU_VMALLOC_ALIGN getpagesize()
+#endif
+
#include "config-host.h"
#include "sysemu.h"
#include "trace.h"
@@ -80,7 +87,12 @@ void *qemu_memalign(size_t alignment, size_t size)
void *qemu_vmalloc(size_t size)
{
void *ptr;
- ptr = qemu_memalign(getpagesize(), size);
+ size_t align = QEMU_VMALLOC_ALIGN;
+
+ if (size < align) {
+ align = getpagesize();
+ }
+ ptr = qemu_memalign(align, size);
trace_qemu_vmalloc(size, ptr);
return ptr;
}
--
1.7.7
- [Qemu-stable] [PATCH stable-0.15 15/36] ac97: don't override the pci subsystem id, (continued)
- [Qemu-stable] [PATCH stable-0.15 15/36] ac97: don't override the pci subsystem id, Andreas Färber, 2012/03/28
- [Qemu-stable] [PATCH stable-0.15 06/36] compatfd.c: Don't pass NULL pointer to SYS_signalfd, Andreas Färber, 2012/03/28
- [Qemu-stable] [PATCH stable-0.15 05/36] e1000: bounds packet size against buffer size, Andreas Färber, 2012/03/28
- [Qemu-stable] [PATCH stable-0.15 33/36] pc: add pc-0.15, Andreas Färber, 2012/03/28
- [Qemu-stable] [PATCH stable-0.15 12/36] migration: flush migration data to disk., Andreas Färber, 2012/03/28
- [Qemu-stable] [PATCH stable-0.15 02/36] qdev: Reset hot-plugged devices, Andreas Färber, 2012/03/28
- [Qemu-stable] [PATCH stable-0.15 18/36] block/curl: Implement a flush function on the fd handlers, Andreas Färber, 2012/03/28
- [Qemu-stable] [PATCH stable-0.15 16/36] vvfat: Fix potential buffer overflow, Andreas Färber, 2012/03/28
- [Qemu-stable] [PATCH stable-0.15 32/36] Error check find_ram_offset, Andreas Färber, 2012/03/28
- [Qemu-stable] [PATCH stable-0.15 31/36] cpu-common: Have a ram_addr_t of uint64 with Xen., Andreas Färber, 2012/03/28
- [Qemu-stable] [PATCH stable-0.15 36/36] qemu_vmalloc: align properly for transparent hugepages and KVM,
Andreas Färber <=
- [Qemu-stable] [PATCH stable-0.15 21/36] Teach block/vdi about "discarded" (no longer allocated) blocks, Andreas Färber, 2012/03/28
- [Qemu-stable] [PATCH stable-0.15 30/36] pc: Fix floppy drives with if=none, Andreas Färber, 2012/03/28
- [Qemu-stable] [PATCH stable-0.15 22/36] vmdk: Improve error handling, Andreas Färber, 2012/03/28
- [Qemu-stable] [PATCH stable-0.15 28/36] qxl: stride fixup, Andreas Färber, 2012/03/28
- [Qemu-stable] [PATCH stable-0.15 26/36] qcow: Fix bdrv_write_compressed error handling, Andreas Färber, 2012/03/28
- [Qemu-stable] [PATCH stable-0.15 24/36] console: Fix rendering of VGA underline, Andreas Färber, 2012/03/28
- [Qemu-stable] [PATCH stable-0.15 19/36] hda: do not mix output and input streams, RHBZ #740493, Andreas Färber, 2012/03/28
- Re: [Qemu-stable] [Qemu-devel] [PATCH stable-0.15 00/36] Preparing 0.15.2, Stefan Weil, 2012/03/28