[Libguestfs] [PATCH libnbd 6/8] copy: Keep worker pointer in command
Nir Soffer
nsoffer at redhat.com
Sun Feb 20 12:14:01 UTC 2022
Replace the command index with a worker pointer. The nbd-ops access the
index via the worker pointer. This allows commands to modify worker
state during processing.
Signed-off-by: Nir Soffer <nsoffer at redhat.com>
---
copy/multi-thread-copying.c | 12 ++++++------
copy/nbd-ops.c | 6 +++---
copy/nbdcopy.h | 2 +-
3 files changed, 10 insertions(+), 10 deletions(-)
diff --git a/copy/multi-thread-copying.c b/copy/multi-thread-copying.c
index a1a8d09c..8ba721fe 100644
--- a/copy/multi-thread-copying.c
+++ b/copy/multi-thread-copying.c
@@ -131,21 +131,21 @@ multi_thread_copying (void)
}
static void wait_for_request_slots (size_t index);
static unsigned in_flight (size_t index);
static void poll_both_ends (size_t index);
static int finished_read (void *vp, int *error);
static int finished_command (void *vp, int *error);
static void free_command (struct command *command);
static void fill_dst_range_with_zeroes (struct command *command);
static struct command *create_command (uint64_t offset, size_t len, bool zero,
- size_t index);
+ struct worker *worker);
/* There are 'threads' worker threads, each copying work ranges from
* src to dst until there are no more work ranges.
*/
static void *
worker_thread (void *wp)
{
struct worker *w = wp;
uint64_t offset, count;
extent_list exts = empty_vector;
@@ -161,36 +161,36 @@ worker_thread (void *wp)
for (i = 0; i < exts.len; ++i) {
struct command *command;
size_t len;
if (exts.ptr[i].zero) {
/* The source is zero so we can proceed directly to skipping,
* fast zeroing, or writing zeroes at the destination.
*/
command = create_command (exts.ptr[i].offset, exts.ptr[i].length,
- true, w->index);
+ true, w);
fill_dst_range_with_zeroes (command);
}
else /* data */ {
/* As the extent might be larger than permitted for a single
* command, we may have to split this into multiple read
* requests.
*/
while (exts.ptr[i].length > 0) {
len = exts.ptr[i].length;
if (len > request_size)
len = request_size;
command = create_command (exts.ptr[i].offset, len,
- false, w->index);
+ false, w);
wait_for_request_slots (w->index);
/* Begin the asynch read operation. */
src->ops->asynch_read (src, command,
(nbd_completion_callback) {
.callback = finished_read,
.user_data = command,
});
@@ -332,38 +332,38 @@ create_buffer (size_t len)
exit (EXIT_FAILURE);
}
buffer->refs = 1;
return buffer;
}
/* Create a new command for read or zero. */
static struct command *
-create_command (uint64_t offset, size_t len, bool zero, size_t index)
+create_command (uint64_t offset, size_t len, bool zero, struct worker *worker)
{
struct command *command;
command = calloc (1, sizeof *command);
if (command == NULL) {
perror ("calloc");
exit (EXIT_FAILURE);
}
command->offset = offset;
command->slice.len = len;
command->slice.base = 0;
if (!zero)
command->slice.buffer = create_buffer (len);
- command->index = index;
+ command->worker = worker;
return command;
}
/* Create a sub-command of an existing command. This creates a slice
* referencing the buffer of the existing command without copying.
*/
static struct command *
create_subcommand (struct command *command, uint64_t offset, size_t len,
bool zero)
@@ -379,21 +379,21 @@ create_subcommand (struct command *command, uint64_t offset, size_t len,
perror ("calloc");
exit (EXIT_FAILURE);
}
newcommand->offset = offset;
newcommand->slice.len = len;
if (!zero) {
newcommand->slice.buffer = command->slice.buffer;
newcommand->slice.buffer->refs++;
newcommand->slice.base = offset - command->offset;
}
- newcommand->index = command->index;
+ newcommand->worker = command->worker;
return newcommand;
}
/* Callback called when src has finished one read command. This
* initiates a write.
*/
static int
finished_read (void *vp, int *error)
{
diff --git a/copy/nbd-ops.c b/copy/nbd-ops.c
index dca86e88..adfe4de5 100644
--- a/copy/nbd-ops.c
+++ b/copy/nbd-ops.c
@@ -296,57 +296,57 @@ nbd_ops_synch_zero (struct rw *rw, uint64_t offset, uint64_t count,
return true;
}
static void
nbd_ops_asynch_read (struct rw *rw,
struct command *command,
nbd_completion_callback cb)
{
struct rw_nbd *rwn = (struct rw_nbd *) rw;
- if (nbd_aio_pread (rwn->handles.ptr[command->index],
+ if (nbd_aio_pread (rwn->handles.ptr[command->worker->index],
slice_ptr (command->slice),
command->slice.len, command->offset,
cb, 0) == -1) {
fprintf (stderr, "%s: %s\n", rw->name, nbd_get_error ());
exit (EXIT_FAILURE);
}
}
static void
nbd_ops_asynch_write (struct rw *rw,
struct command *command,
nbd_completion_callback cb)
{
struct rw_nbd *rwn = (struct rw_nbd *) rw;
- if (nbd_aio_pwrite (rwn->handles.ptr[command->index],
+ if (nbd_aio_pwrite (rwn->handles.ptr[command->worker->index],
slice_ptr (command->slice),
command->slice.len, command->offset,
cb, 0) == -1) {
fprintf (stderr, "%s: %s\n", rw->name, nbd_get_error ());
exit (EXIT_FAILURE);
}
}
static bool
nbd_ops_asynch_zero (struct rw *rw, struct command *command,
nbd_completion_callback cb, bool allocate)
{
struct rw_nbd *rwn = (struct rw_nbd *) rw;
if (!rwn->can_zero)
return false;
assert (command->slice.len <= UINT32_MAX);
- if (nbd_aio_zero (rwn->handles.ptr[command->index],
+ if (nbd_aio_zero (rwn->handles.ptr[command->worker->index],
command->slice.len, command->offset,
cb, allocate ? LIBNBD_CMD_FLAG_NO_HOLE : 0) == -1) {
fprintf (stderr, "%s: %s\n", rw->name, nbd_get_error ());
exit (EXIT_FAILURE);
}
return true;
}
static int
add_extent (void *vp, const char *metacontext,
diff --git a/copy/nbdcopy.h b/copy/nbdcopy.h
index 4fe8bee6..8027836b 100644
--- a/copy/nbdcopy.h
+++ b/copy/nbdcopy.h
@@ -92,21 +92,21 @@ struct worker {
*
* slice.buffer may be NULL for commands (like zero) that have no
* associated data.
*
* A separate set of commands, slices and buffers is maintained per
* thread so no locking is necessary.
*/
struct command {
uint64_t offset; /* Offset relative to start of disk. */
struct slice slice; /* Data slice. */
- size_t index; /* Thread number. */
+ struct worker *worker; /* The worker owning this command. */
};
/* List of extents for rw->ops->get_extents. */
struct extent {
uint64_t offset;
uint64_t length;
bool zero;
};
DEFINE_VECTOR_TYPE(extent_list, struct extent);
--
2.35.1
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