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[Qemu-devel] [RFC PATCH] Convert ram_list to RCU DQ V2
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From: |
Mike Day |
|
Subject: |
[Qemu-devel] [RFC PATCH] Convert ram_list to RCU DQ V2 |
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Date: |
Fri, 30 Aug 2013 12:06:57 -0400 |
Changes from V1:
* Omitted locks or rcu critical sections within Some functions that
read or write the ram_list but are called in a protected context
(the caller holds the iothread lock, the ram_list mutex, or an rcu
critical section).
Allow "unlocked" reads of the ram_list by using an RCU-enabled
DQ. Most readers of the list no longer require holding the list mutex.
The ram_list now uses a QLIST instead of a QTAILQ. The difference is
minimal.
This patch has been built and make-checked for the x86_64, ppc64,
s390x, and arm targets. It has not been tested further than that at
this point.
To apply this patch, you must base upon Paolo Bonzini's rcu tree and
also apply the RCU DQ patch (below).
https://github.com/bonzini/qemu/tree/rcu
http://article.gmane.org/gmane.comp.emulators.qemu/230159/
Signed-off-by: Mike Day <address@hidden>
---
arch_init.c | 80 +++++++++++++++-----------
exec.c | 142 ++++++++++++++++++++++++++++++----------------
hw/9pfs/virtio-9p-synth.c | 2 +-
include/exec/cpu-all.h | 4 +-
include/qemu/rcu_queue.h | 8 +++
5 files changed, 151 insertions(+), 85 deletions(-)
diff --git a/arch_init.c b/arch_init.c
index 68a7ab7..3f4d676 100644
--- a/arch_init.c
+++ b/arch_init.c
@@ -49,6 +49,7 @@
#include "trace.h"
#include "exec/cpu-all.h"
#include "hw/acpi/acpi.h"
+#include "qemu/rcu_queue.h"
#ifdef DEBUG_ARCH_INIT
#define DPRINTF(fmt, ...) \
@@ -398,7 +399,11 @@ static void migration_bitmap_sync(void)
trace_migration_bitmap_sync_start();
address_space_sync_dirty_bitmap(&address_space_memory);
- QTAILQ_FOREACH(block, &ram_list.blocks, next) {
+ /* This assumes the iothread lock or the ram_list mutex is taken.
+ * if that changes, accesses to ram_list need to be protected
+ * by a mutex (writes) or an rcu read lock (reads)
+ */
+ QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
for (addr = 0; addr < block->length; addr += TARGET_PAGE_SIZE) {
if (memory_region_test_and_clear_dirty(block->mr,
addr, TARGET_PAGE_SIZE,
@@ -457,8 +462,13 @@ static int ram_save_block(QEMUFile *f, bool last_stage)
MemoryRegion *mr;
ram_addr_t current_addr;
+ /* Sometimes called with the ram_list mutex held (ram_save_complete)
+ * also called WITHOUT the ram_list mutex held. (ram_save_iterate).
+ * Protect ram_list with an rcu critical section.
+ */
+ rcu_read_lock();
if (!block)
- block = QTAILQ_FIRST(&ram_list.blocks);
+ block = QLIST_FIRST_RCU(&ram_list.blocks);
while (true) {
mr = block->mr;
@@ -469,9 +479,9 @@ static int ram_save_block(QEMUFile *f, bool last_stage)
}
if (offset >= block->length) {
offset = 0;
- block = QTAILQ_NEXT(block, next);
+ block = QLIST_NEXT_RCU(block, next);
if (!block) {
- block = QTAILQ_FIRST(&ram_list.blocks);
+ block = QLIST_FIRST_RCU(&ram_list.blocks);
complete_round = true;
ram_bulk_stage = false;
}
@@ -526,6 +536,7 @@ static int ram_save_block(QEMUFile *f, bool last_stage)
}
}
}
+ rcu_read_unlock();
last_seen_block = block;
last_offset = offset;
@@ -565,10 +576,10 @@ uint64_t ram_bytes_total(void)
{
RAMBlock *block;
uint64_t total = 0;
-
- QTAILQ_FOREACH(block, &ram_list.blocks, next)
+ rcu_read_lock();
+ QLIST_FOREACH_RCU(block, &ram_list.blocks, next)
total += block->length;
-
+ rcu_read_unlock();
return total;
}
@@ -631,7 +642,7 @@ static int ram_save_setup(QEMUFile *f, void *opaque)
}
qemu_mutex_lock_iothread();
- qemu_mutex_lock_ramlist();
+ rcu_read_lock();
bytes_transferred = 0;
reset_ram_globals();
@@ -641,13 +652,13 @@ static int ram_save_setup(QEMUFile *f, void *opaque)
qemu_put_be64(f, ram_bytes_total() | RAM_SAVE_FLAG_MEM_SIZE);
- QTAILQ_FOREACH(block, &ram_list.blocks, next) {
+ QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
qemu_put_byte(f, strlen(block->idstr));
qemu_put_buffer(f, (uint8_t *)block->idstr, strlen(block->idstr));
qemu_put_be64(f, block->length);
}
- qemu_mutex_unlock_ramlist();
+ rcu_read_unlock();
ram_control_before_iterate(f, RAM_CONTROL_SETUP);
ram_control_after_iterate(f, RAM_CONTROL_SETUP);
@@ -664,8 +675,6 @@ static int ram_save_iterate(QEMUFile *f, void *opaque)
int64_t t0;
int total_sent = 0;
- qemu_mutex_lock_ramlist();
-
if (ram_list.version != last_version) {
reset_ram_globals();
}
@@ -701,8 +710,6 @@ static int ram_save_iterate(QEMUFile *f, void *opaque)
i++;
}
- qemu_mutex_unlock_ramlist();
-
/*
* Must occur before EOS (or any QEMUFile operation)
* because of RDMA protocol.
@@ -815,6 +822,10 @@ static inline void *host_from_stream_offset(QEMUFile *f,
char id[256];
uint8_t len;
+ /* Must be called from within a rcu critical section.
+ * Returns a pointer from within the RCU-protected ram_list.
+ */
+
if (flags & RAM_SAVE_FLAG_CONTINUE) {
if (!block) {
fprintf(stderr, "Ack, bad migration stream!\n");
@@ -828,9 +839,10 @@ static inline void *host_from_stream_offset(QEMUFile *f,
qemu_get_buffer(f, (uint8_t *)id, len);
id[len] = 0;
- QTAILQ_FOREACH(block, &ram_list.blocks, next) {
- if (!strncmp(id, block->idstr, sizeof(id)))
+ QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
+ if (!strncmp(id, block->idstr, sizeof(id))) {
return memory_region_get_ram_ptr(block->mr) + offset;
+ }
}
fprintf(stderr, "Can't find block %s!\n", id);
@@ -867,7 +879,12 @@ static int ram_load(QEMUFile *f, void *opaque, int
version_id)
if (version_id < 4 || version_id > 4) {
return -EINVAL;
}
-
+ /* this implements a long-running RCU critical section.
+ * When rcu reclaims in the code start to become numerous
+ * it will be necessary to reduce the granularity of this critical
+ * section.
+ */
+ rcu_read_lock();
do {
addr = qemu_get_be64(f);
@@ -889,21 +906,19 @@ static int ram_load(QEMUFile *f, void *opaque, int
version_id)
qemu_get_buffer(f, (uint8_t *)id, len);
id[len] = 0;
length = qemu_get_be64(f);
-
- QTAILQ_FOREACH(block, &ram_list.blocks, next) {
+ QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
if (!strncmp(id, block->idstr, sizeof(id))) {
if (block->length != length) {
fprintf(stderr,
"Length mismatch: %s: " RAM_ADDR_FMT
" in != " RAM_ADDR_FMT "\n", id,
length,
block->length);
- ret = -EINVAL;
+ ret = -EINVAL;
goto done;
}
break;
}
}
-
if (!block) {
fprintf(stderr, "Unknown ramblock \"%s\", cannot "
"accept migration\n", id);
@@ -916,30 +931,30 @@ static int ram_load(QEMUFile *f, void *opaque, int
version_id)
}
}
+ /* Call host_from_stream_offset while holding an rcu read lock.
+ * It returns a pointer from within the rcu-protected ram_list.
+ */
if (flags & RAM_SAVE_FLAG_COMPRESS) {
- void *host;
uint8_t ch;
-
- host = host_from_stream_offset(f, addr, flags);
+ void *host = host_from_stream_offset(f, addr, flags);
if (!host) {
- return -EINVAL;
+ ret = -EINVAL;
+ goto done;
}
-
ch = qemu_get_byte(f);
ram_handle_compressed(host, ch, TARGET_PAGE_SIZE);
} else if (flags & RAM_SAVE_FLAG_PAGE) {
- void *host;
-
- host = host_from_stream_offset(f, addr, flags);
+ void *host = host_from_stream_offset(f, addr, flags);
if (!host) {
- return -EINVAL;
+ ret = -EINVAL;
+ goto done;
}
-
qemu_get_buffer(f, host, TARGET_PAGE_SIZE);
} else if (flags & RAM_SAVE_FLAG_XBZRLE) {
void *host = host_from_stream_offset(f, addr, flags);
if (!host) {
- return -EINVAL;
+ ret = -EINVAL;
+ goto done;
}
if (load_xbzrle(f, addr, host) < 0) {
@@ -957,6 +972,7 @@ static int ram_load(QEMUFile *f, void *opaque, int
version_id)
} while (!(flags & RAM_SAVE_FLAG_EOS));
done:
+ rcu_read_unlock();
DPRINTF("Completed load of VM with exit code %d seq iteration "
"%" PRIu64 "\n", ret, seq_iter);
return ret;
diff --git a/exec.c b/exec.c
index 5eebcc1..d1132da 100644
--- a/exec.c
+++ b/exec.c
@@ -46,7 +46,7 @@
#endif
#include "exec/cpu-all.h"
#include "qemu/tls.h"
-
+#include "qemu/rcu_queue.h"
#include "exec/cputlb.h"
#include "translate-all.h"
@@ -57,7 +57,7 @@
#if !defined(CONFIG_USER_ONLY)
static int in_migration;
-RAMList ram_list = { .blocks = QTAILQ_HEAD_INITIALIZER(ram_list.blocks) };
+RAMList ram_list = { .blocks = QLIST_HEAD_INITIALIZER(ram_list.blocks) };
static MemoryRegion *system_memory;
static MemoryRegion *system_io;
@@ -1021,17 +1021,24 @@ static ram_addr_t find_ram_offset(ram_addr_t size)
RAMBlock *block, *next_block;
ram_addr_t offset = RAM_ADDR_MAX, mingap = RAM_ADDR_MAX;
+ /* ram_list must be protected by a mutex (for writes), or
+ * an rcu critical section (for reads). Currently this code
+ * is called with the iothread lock held. If that changes,
+ * make sure to protect ram_list with an rcu critical section.
+ */
+
assert(size != 0); /* it would hand out same offset multiple times */
- if (QTAILQ_EMPTY(&ram_list.blocks))
+ if (QLIST_EMPTY_RCU(&ram_list.blocks)) {
return 0;
+ }
- QTAILQ_FOREACH(block, &ram_list.blocks, next) {
+ QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
ram_addr_t end, next = RAM_ADDR_MAX;
end = block->offset + block->length;
- QTAILQ_FOREACH(next_block, &ram_list.blocks, next) {
+ QLIST_FOREACH_RCU(next_block, &ram_list.blocks, next) {
if (next_block->offset >= end) {
next = MIN(next, next_block->offset);
}
@@ -1056,9 +1063,11 @@ ram_addr_t last_ram_offset(void)
RAMBlock *block;
ram_addr_t last = 0;
- QTAILQ_FOREACH(block, &ram_list.blocks, next)
+ rcu_read_lock();
+ QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
last = MAX(last, block->offset + block->length);
-
+ }
+ rcu_read_unlock();
return last;
}
@@ -1083,7 +1092,12 @@ void qemu_ram_set_idstr(ram_addr_t addr, const char
*name, DeviceState *dev)
RAMBlock *new_block, *block;
new_block = NULL;
- QTAILQ_FOREACH(block, &ram_list.blocks, next) {
+
+ /* Assumes that the iothread lock is taken ... if that changes,
+ * add an rcu_read_lock()/unlock pair when traversing the
+ * ram list
+ */
+ QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
if (block->offset == addr) {
new_block = block;
break;
@@ -1102,15 +1116,13 @@ void qemu_ram_set_idstr(ram_addr_t addr, const char
*name, DeviceState *dev)
pstrcat(new_block->idstr, sizeof(new_block->idstr), name);
/* This assumes the iothread lock is taken here too. */
- qemu_mutex_lock_ramlist();
- QTAILQ_FOREACH(block, &ram_list.blocks, next) {
+ QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
if (block != new_block && !strcmp(block->idstr, new_block->idstr)) {
fprintf(stderr, "RAMBlock \"%s\" already registered, abort!\n",
new_block->idstr);
abort();
}
}
- qemu_mutex_unlock_ramlist();
}
static int memory_try_enable_merging(void *addr, size_t len)
@@ -1126,13 +1138,18 @@ static int memory_try_enable_merging(void *addr, size_t
len)
ram_addr_t qemu_ram_alloc_from_ptr(ram_addr_t size, void *host,
MemoryRegion *mr)
{
- RAMBlock *block, *new_block;
+ RAMBlock *block, *new_block, *last_block = 0;
size = TARGET_PAGE_ALIGN(size);
new_block = g_malloc0(sizeof(*new_block));
- /* This assumes the iothread lock is taken here too. */
- qemu_mutex_lock_ramlist();
+ /* ram_list needs to be protected by the ram_list mutex
+ * for writes, and by an rcu critical section for reads.
+ * Currently this function is called with the iothread lock
+ * being held, so we can foregoe protecting the ram_list.
+ * when that changes, acquire the ram_list mutex before
+ * sorting and writing the list below.
+ */
new_block->mr = mr;
new_block->offset = find_ram_offset(size);
if (host) {
@@ -1164,21 +1181,28 @@ ram_addr_t qemu_ram_alloc_from_ptr(ram_addr_t size,
void *host,
}
new_block->length = size;
+ /* when this code is called without the iothread lock, protect
+ * the ram_list here by acquiring its mutex.
+ */
/* Keep the list sorted from biggest to smallest block. */
- QTAILQ_FOREACH(block, &ram_list.blocks, next) {
+ QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
+ last_block = block;
if (block->length < new_block->length) {
break;
}
}
if (block) {
- QTAILQ_INSERT_BEFORE(block, new_block, next);
+ QLIST_INSERT_BEFORE_RCU(block, new_block, next);
} else {
- QTAILQ_INSERT_TAIL(&ram_list.blocks, new_block, next);
+ if (last_block) {
+ QLIST_INSERT_AFTER_RCU(last_block, new_block, next);
+ } else { /* list is empty */
+ QLIST_INSERT_HEAD_RCU(&ram_list.blocks, new_block, next);
+ }
}
ram_list.mru_block = NULL;
ram_list.version++;
- qemu_mutex_unlock_ramlist();
ram_list.phys_dirty = g_realloc(ram_list.phys_dirty,
last_ram_offset() >> TARGET_PAGE_BITS);
@@ -1204,29 +1228,32 @@ void qemu_ram_free_from_ptr(ram_addr_t addr)
{
RAMBlock *block;
- /* This assumes the iothread lock is taken here too. */
- qemu_mutex_lock_ramlist();
- QTAILQ_FOREACH(block, &ram_list.blocks, next) {
+ /* This assumes the iothread lock is taken here too.
+ * when this code is called without the iothread lock, protect
+ * the ram_list here by acquiring its mutex.
+ */
+ QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
if (addr == block->offset) {
- QTAILQ_REMOVE(&ram_list.blocks, block, next);
+ QLIST_REMOVE_RCU(block, next);
ram_list.mru_block = NULL;
ram_list.version++;
g_free(block);
break;
}
}
- qemu_mutex_unlock_ramlist();
}
void qemu_ram_free(ram_addr_t addr)
{
RAMBlock *block;
- /* This assumes the iothread lock is taken here too. */
- qemu_mutex_lock_ramlist();
- QTAILQ_FOREACH(block, &ram_list.blocks, next) {
+ /* This assumes the iothread lock is taken here too.
+ * if that changes, accesses to ram_list need to be protected
+ * by a mutex (writes) or an rcu read lock (reads)
+ */
+ QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
if (addr == block->offset) {
- QTAILQ_REMOVE(&ram_list.blocks, block, next);
+ QLIST_REMOVE_RCU(block, next);
ram_list.mru_block = NULL;
ram_list.version++;
if (block->flags & RAM_PREALLOC_MASK) {
@@ -1253,8 +1280,6 @@ void qemu_ram_free(ram_addr_t addr)
break;
}
}
- qemu_mutex_unlock_ramlist();
-
}
#ifndef _WIN32
@@ -1265,7 +1290,8 @@ void qemu_ram_remap(ram_addr_t addr, ram_addr_t length)
int flags;
void *area, *vaddr;
- QTAILQ_FOREACH(block, &ram_list.blocks, next) {
+ rcu_read_lock();
+ QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
offset = addr - block->offset;
if (offset < block->length) {
vaddr = block->host + offset;
@@ -1313,9 +1339,11 @@ void qemu_ram_remap(ram_addr_t addr, ram_addr_t length)
memory_try_enable_merging(vaddr, length);
qemu_ram_setup_dump(vaddr, length);
}
- return;
+ goto unlock_out;
}
}
+unlock_out:
+ rcu_read_unlock();
}
#endif /* !_WIN32 */
@@ -1323,12 +1351,15 @@ static RAMBlock *qemu_get_ram_block(ram_addr_t addr)
{
RAMBlock *block;
- /* The list is protected by the iothread lock here. */
+ /* This assumes the iothread lock is taken here too.
+ * if that changes, accesses to ram_list need to be protected
+ * by a mutex (writes) or an rcu read lock (reads)
+ */
block = ram_list.mru_block;
if (block && addr - block->offset < block->length) {
goto found;
}
- QTAILQ_FOREACH(block, &ram_list.blocks, next) {
+ QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
if (addr - block->offset < block->length) {
goto found;
}
@@ -1378,8 +1409,11 @@ static void *qemu_safe_ram_ptr(ram_addr_t addr)
{
RAMBlock *block;
- /* The list is protected by the iothread lock here. */
- QTAILQ_FOREACH(block, &ram_list.blocks, next) {
+ /* This assumes the iothread lock is taken here too.
+ * if that changes, accesses to ram_list need to be protected
+ * by a mutex (writes) or an rcu read lock (reads)
+ */
+ QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
if (addr - block->offset < block->length) {
if (xen_enabled()) {
/* We need to check if the requested address is in the RAM
@@ -1399,7 +1433,6 @@ static void *qemu_safe_ram_ptr(ram_addr_t addr)
fprintf(stderr, "Bad ram offset %" PRIx64 "\n", (uint64_t)addr);
abort();
-
return NULL;
}
@@ -1407,6 +1440,7 @@ static void *qemu_safe_ram_ptr(ram_addr_t addr)
* but takes a size argument */
static void *qemu_ram_ptr_length(ram_addr_t addr, hwaddr *size)
{
+ void *ptr = NULL;
if (*size == 0) {
return NULL;
}
@@ -1414,18 +1448,22 @@ static void *qemu_ram_ptr_length(ram_addr_t addr,
hwaddr *size)
return xen_map_cache(addr, *size, 1);
} else {
RAMBlock *block;
-
- QTAILQ_FOREACH(block, &ram_list.blocks, next) {
+ rcu_read_lock();
+ QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
if (addr - block->offset < block->length) {
if (addr - block->offset + *size > block->length)
*size = block->length - addr + block->offset;
- return block->host + (addr - block->offset);
+ ptr = block->host + (addr - block->offset);
+ goto unlock_out;
}
}
fprintf(stderr, "Bad ram offset %" PRIx64 "\n", (uint64_t)addr);
abort();
}
+unlock_out:
+ rcu_read_unlock();
+ return ptr;
}
/* Some of the softmmu routines need to translate from a host pointer
@@ -1434,32 +1472,35 @@ MemoryRegion *qemu_ram_addr_from_host(void *ptr,
ram_addr_t *ram_addr)
{
RAMBlock *block;
uint8_t *host = ptr;
+ MemoryRegion *mr = NULL;
if (xen_enabled()) {
*ram_addr = xen_ram_addr_from_mapcache(ptr);
return qemu_get_ram_block(*ram_addr)->mr;
}
-
+ rcu_read_lock();
block = ram_list.mru_block;
if (block && block->host && host - block->host < block->length) {
- goto found;
+ *ram_addr = block->offset + (host - block->host);
+ mr = block->mr;
+ goto unlock_out;
}
- QTAILQ_FOREACH(block, &ram_list.blocks, next) {
+ QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
/* This case append when the block is not mapped. */
if (block->host == NULL) {
continue;
}
if (host - block->host < block->length) {
- goto found;
+ *ram_addr = block->offset + (host - block->host);
+ mr = block->mr;
+ goto unlock_out;
}
}
- return NULL;
-
-found:
- *ram_addr = block->offset + (host - block->host);
- return block->mr;
+unlock_out:
+ rcu_read_unlock();
+ return mr;
}
static void notdirty_mem_write(void *opaque, hwaddr ram_addr,
@@ -2709,9 +2750,10 @@ bool cpu_physical_memory_is_io(hwaddr phys_addr)
void qemu_ram_foreach_block(RAMBlockIterFunc func, void *opaque)
{
RAMBlock *block;
-
- QTAILQ_FOREACH(block, &ram_list.blocks, next) {
+ rcu_read_lock();
+ QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
func(block->host, block->offset, block->length, opaque);
}
+ rcu_read_unlock();
}
#endif
diff --git a/hw/9pfs/virtio-9p-synth.c b/hw/9pfs/virtio-9p-synth.c
index fdfea21..c2efaca 100644
--- a/hw/9pfs/virtio-9p-synth.c
+++ b/hw/9pfs/virtio-9p-synth.c
@@ -18,7 +18,7 @@
#include "fsdev/qemu-fsdev.h"
#include "virtio-9p-synth.h"
#include "qemu/rcu.h"
-
+#include "qemu/rcu_queue.h"
#include <sys/stat.h>
/* Root node for synth file system */
diff --git a/include/exec/cpu-all.h b/include/exec/cpu-all.h
index e088089..9cd8a30 100644
--- a/include/exec/cpu-all.h
+++ b/include/exec/cpu-all.h
@@ -457,7 +457,7 @@ typedef struct RAMBlock {
/* Reads can take either the iothread or the ramlist lock.
* Writes must take both locks.
*/
- QTAILQ_ENTRY(RAMBlock) next;
+ QLIST_ENTRY(RAMBlock) next;
#if defined(__linux__) && !defined(TARGET_S390X)
int fd;
#endif
@@ -469,7 +469,7 @@ typedef struct RAMList {
uint8_t *phys_dirty;
RAMBlock *mru_block;
/* Protected by the ramlist lock. */
- QTAILQ_HEAD(, RAMBlock) blocks;
+ QLIST_HEAD(, RAMBlock) blocks;
uint32_t version;
} RAMList;
extern RAMList ram_list;
diff --git a/include/qemu/rcu_queue.h b/include/qemu/rcu_queue.h
index e2b8ba5..d159850 100644
--- a/include/qemu/rcu_queue.h
+++ b/include/qemu/rcu_queue.h
@@ -37,6 +37,14 @@
extern "C" {
#endif
+
+/*
+ * List access methods.
+ */
+#define QLIST_EMPTY_RCU(head) (atomic_rcu_read(&(head)->lh_first) == NULL)
+#define QLIST_FIRST_RCU(head) (atomic_rcu_read(&(head)->lh_first))
+#define QLIST_NEXT_RCU(elm, field) (atomic_rcu_read(&(elm)->field.le_next))
+
/*
* List functions.
*/
--
1.8.3.1
- [Qemu-devel] [RFC PATCH] Convert ram_list to RCU DQ V2,
Mike Day <=