Author: stefan2
Date: Fri Aug 22 16:18:06 2014
New Revision: 1619857
URL: http://svn.apache.org/r1619857
Log:
On the revprop-caching-ng branch: Replace the SHM objects by an open
file handle to the revprops generation file allowing modifications from
different machines. Re-enable the feature.
To clean up the code, we bind the existence of the revprop-generation
file to repo format 7. It gets created with the repo and auto-inserted /
replaced by 'svnadmin upgrade'. With older formats, we will not try to
use the new infrastructure anymore.
This patch does not address the fact that generation bumps are no longer
atomic. Apart from that, the functionality is the same as until recently
on trunk with the single machine limitation removed.
* subversion/libsvn_fs_fs/fs.h
(SVN_FS_FS__MIN_REVPROP_CACHING_FORMAT): New feature availability limit.
(fs_fs_data_t): Replace SHM objects with a single file handle.
* subversion/libsvn_fs_fs/revprops.h
(svn_fs_fs__write_revprop_generation_file,
svn_fs_fs__cleanup_revprop_namespace): Replaced by ...
(svn_fs_fs__reset_revprop_generation_file): ... this new function.
* subversion/libsvn_fs_fs/fs_fs.c
(upgrade_body,
svn_fs_fs__create): Call the new reset function to cleanup and auto-
create the generation file.
* subversion/libsvn_fs_fs/hotcopy.c
(hotcopy_body): Ensure that the target has a valid generation file.
* subversion/libsvn_fs_fs/recovery.c
(recover_body): Same for the repo being recovered.
* subversion/libsvn_fs_fs/caching.c
(read_config): Re-enable the revprop cache feature. But we have only
"on" and "off" now. "on" does not mean that we will
actually use the cache instance for the repo at hand.
* subversion/libsvn_fs_fs/revprops.c
(Revprop caching management): Add a docstring TODO for later.
(read_revprop_generation_file,
svn_fs_fs__write_revprop_generation_file,
ensure_revprop_namespace,
svn_fs_fs__cleanup_revprop_namespace,
ensure_revprop_generation,
ensure_revprop_timeout): Remove this old code. Some similarly named
functions may be found in the next block.
(ensure_revprop_generation,
read_revprop_generation_file,
write_revprop_generation_file,
svn_fs_fs__reset_revprop_generation_file): New code to open, read,
write and auto-create the
generation file.
(has_revprop_cache): File-based now and not supported by all formats.
(revprop_generation_fixup_t,
revprop_generation_fixup,
read_revprop_generation): Use file timestamps now for crash timeout
detection and update recovery code.
(begin_revprop_change,
end_revprop_change): Update the generation bump logic to simple calls
of the file read / writer functions and leverage
the fact that we hold the write lock. No retries
required at this level and the generation value
is predictable after the first read.
(switch_to_new_revprop): Update caller.
Modified:
subversion/branches/revprop-caching-ng/subversion/libsvn_fs_fs/caching.c
subversion/branches/revprop-caching-ng/subversion/libsvn_fs_fs/fs.h
subversion/branches/revprop-caching-ng/subversion/libsvn_fs_fs/fs_fs.c
subversion/branches/revprop-caching-ng/subversion/libsvn_fs_fs/hotcopy.c
subversion/branches/revprop-caching-ng/subversion/libsvn_fs_fs/recovery.c
subversion/branches/revprop-caching-ng/subversion/libsvn_fs_fs/revprops.c
subversion/branches/revprop-caching-ng/subversion/libsvn_fs_fs/revprops.h
Modified:
subversion/branches/revprop-caching-ng/subversion/libsvn_fs_fs/caching.c
URL:
http://svn.apache.org/viewvc/subversion/branches/revprop-caching-ng/subversion/libsvn_fs_fs/caching.c?rev=1619857&r1=1619856&r2=1619857&view=diff
==============================================================================
--- subversion/branches/revprop-caching-ng/subversion/libsvn_fs_fs/caching.c
(original)
+++ subversion/branches/revprop-caching-ng/subversion/libsvn_fs_fs/caching.c
Fri Aug 22 16:18:06 2014
@@ -119,9 +119,21 @@ read_config(const char **cache_namespace
SVN_FS_CONFIG_FSFS_CACHE_FULLTEXTS,
TRUE);
- /* For now, always disable revprop caching.
+ /* don't cache revprops by default.
+ * Revprop caching significantly speeds up operations like
+ * svn ls -v. However, it requires synchronization that may
+ * not be available or efficient in the current server setup.
+ * Option "2" is equivalent to "1".
*/
- *cache_revprops = FALSE;
+ if (strcmp(svn_hash__get_cstring(fs->config,
+ SVN_FS_CONFIG_FSFS_CACHE_REVPROPS,
+ ""), "2"))
+ *cache_revprops
+ = svn_hash__get_bool(fs->config,
+ SVN_FS_CONFIG_FSFS_CACHE_REVPROPS,
+ FALSE);
+ else
+ *cache_revprops = TRUE;
return SVN_NO_ERROR;
}
Modified: subversion/branches/revprop-caching-ng/subversion/libsvn_fs_fs/fs.h
URL:
http://svn.apache.org/viewvc/subversion/branches/revprop-caching-ng/subversion/libsvn_fs_fs/fs.h?rev=1619857&r1=1619856&r2=1619857&view=diff
==============================================================================
--- subversion/branches/revprop-caching-ng/subversion/libsvn_fs_fs/fs.h
(original)
+++ subversion/branches/revprop-caching-ng/subversion/libsvn_fs_fs/fs.h Fri Aug
22 16:18:06 2014
@@ -182,6 +182,9 @@ extern "C" {
/* Minimum format number that supports per-instance filesystem IDs. */
#define SVN_FS_FS__MIN_INSTANCE_ID_FORMAT 7
+/* Minimum format number that supports revprop caching. */
+#define SVN_FS_FS__MIN_REVPROP_CACHING_FORMAT 7
+
/* The minimum format number that supports a configuration file (fsfs.conf) */
#define SVN_FS_FS__MIN_CONFIG_FILE 4
@@ -345,17 +348,9 @@ typedef struct fs_fs_data_t
rep key (revision/offset) to svn_stringbuf_t. */
svn_cache__t *fulltext_cache;
- /* Access object to the atomics namespace used by revprop caching.
- Will be NULL until the first access. */
- svn_atomic_namespace__t *revprop_namespace;
-
/* Access object to the revprop "generation". Will be NULL until
- the first access. */
- svn_named_atomic__t *revprop_generation;
-
- /* Access object to the revprop update timeout. Will be NULL until
- the first access. */
- svn_named_atomic__t *revprop_timeout;
+ the first access. May be also get closed and set to NULL again. */
+ apr_file_t *revprop_generation_file;
/* Revision property cache. Maps from (rev,generation) to apr_hash_t. */
svn_cache__t *revprop_cache;
Modified: subversion/branches/revprop-caching-ng/subversion/libsvn_fs_fs/fs_fs.c
URL:
http://svn.apache.org/viewvc/subversion/branches/revprop-caching-ng/subversion/libsvn_fs_fs/fs_fs.c?rev=1619857&r1=1619856&r2=1619857&view=diff
==============================================================================
--- subversion/branches/revprop-caching-ng/subversion/libsvn_fs_fs/fs_fs.c
(original)
+++ subversion/branches/revprop-caching-ng/subversion/libsvn_fs_fs/fs_fs.c Fri
Aug 22 16:18:06 2014
@@ -1206,6 +1206,9 @@ upgrade_body(void *baton, apr_pool_t *po
accidentally uses outdated information. Keep the UUID. */
SVN_ERR(svn_fs_fs__set_uuid(fs, fs->uuid, NULL, pool));
+ /* Initialize / fix up the revprop caching info. */
+ SVN_ERR(svn_fs_fs__reset_revprop_generation_file(fs, pool));
+
/* Bump the format file. */
SVN_ERR(svn_fs_fs__write_format(fs, TRUE, pool));
if (upgrade_baton->notify_func)
@@ -1715,6 +1718,10 @@ svn_fs_fs__create(svn_fs_t *fs,
pool));
}
+ /* Initialize the revprop caching info. */
+ if (format >= SVN_FS_FS__MIN_REVPROP_CACHING_FORMAT)
+ SVN_ERR(svn_fs_fs__reset_revprop_generation_file(fs, pool));
+
/* This filesystem is ready. Stamp it with a format number. */
SVN_ERR(svn_fs_fs__write_format(fs, FALSE, pool));
Modified:
subversion/branches/revprop-caching-ng/subversion/libsvn_fs_fs/hotcopy.c
URL:
http://svn.apache.org/viewvc/subversion/branches/revprop-caching-ng/subversion/libsvn_fs_fs/hotcopy.c?rev=1619857&r1=1619856&r2=1619857&view=diff
==============================================================================
--- subversion/branches/revprop-caching-ng/subversion/libsvn_fs_fs/hotcopy.c
(original)
+++ subversion/branches/revprop-caching-ng/subversion/libsvn_fs_fs/hotcopy.c
Fri Aug 22 16:18:06 2014
@@ -1007,12 +1007,7 @@ hotcopy_body(void *baton, apr_pool_t *po
* reset it to zero (since this is on a different path, it will not
* overlap with data already in cache). Also, clean up stale files
* used for the named atomics implementation. */
- SVN_ERR(svn_io_check_path(svn_fs_fs__path_revprop_generation(src_fs, pool),
- &kind, pool));
- if (kind == svn_node_file)
- SVN_ERR(svn_fs_fs__write_revprop_generation_file(dst_fs, 0, pool));
-
- SVN_ERR(svn_fs_fs__cleanup_revprop_namespace(dst_fs));
+ SVN_ERR(svn_fs_fs__reset_revprop_generation_file(dst_fs, pool));
return SVN_NO_ERROR;
}
Modified:
subversion/branches/revprop-caching-ng/subversion/libsvn_fs_fs/recovery.c
URL:
http://svn.apache.org/viewvc/subversion/branches/revprop-caching-ng/subversion/libsvn_fs_fs/recovery.c?rev=1619857&r1=1619856&r2=1619857&view=diff
==============================================================================
--- subversion/branches/revprop-caching-ng/subversion/libsvn_fs_fs/recovery.c
(original)
+++ subversion/branches/revprop-caching-ng/subversion/libsvn_fs_fs/recovery.c
Fri Aug 22 16:18:06 2014
@@ -345,8 +345,8 @@ recover_body(void *baton, apr_pool_t *po
svn_revnum_t youngest_rev;
svn_node_kind_t youngest_revprops_kind;
- /* Lose potentially corrupted data in temp files */
- SVN_ERR(svn_fs_fs__cleanup_revprop_namespace(fs));
+ /* Revert revprop generation file into a consistent state. */
+ SVN_ERR(svn_fs_fs__reset_revprop_generation_file(fs, pool));
/* We need to know the largest revision in the filesystem. */
SVN_ERR(recover_get_largest_revision(fs, &max_rev, pool));
Modified:
subversion/branches/revprop-caching-ng/subversion/libsvn_fs_fs/revprops.c
URL:
http://svn.apache.org/viewvc/subversion/branches/revprop-caching-ng/subversion/libsvn_fs_fs/revprops.c?rev=1619857&r1=1619856&r2=1619857&view=diff
==============================================================================
--- subversion/branches/revprop-caching-ng/subversion/libsvn_fs_fs/revprops.c
(original)
+++ subversion/branches/revprop-caching-ng/subversion/libsvn_fs_fs/revprops.c
Fri Aug 22 16:18:06 2014
@@ -143,6 +143,8 @@ svn_fs_fs__upgrade_cleanup_pack_revprops
/* Revprop caching management.
*
+ * ### TODO ### Update!
+ *
* Mechanism:
* ----------
*
@@ -194,133 +196,109 @@ svn_fs_fs__upgrade_cleanup_pack_revprops
* initialization phase, they will never operate on stale data.
*/
-/* Read revprop generation as stored on disk for repository FS. The result
- * is returned in *CURRENT. Default to 2 if no such file is available.
+/* Make sure the revprop_generation member in FS is set.
+ * Call only for repos that support revprop caching.
+ */
+static svn_error_t *
+ensure_revprop_generation(svn_fs_t *fs,
+ apr_pool_t *scratch_pool)
+{
+ fs_fs_data_t *ffd = fs->fsap_data;
+ if (ffd->revprop_generation_file == NULL)
+ {
+ const char *path = svn_fs_fs__path_revprop_generation(fs, scratch_pool);
+ SVN_ERR(svn_io_file_open(&ffd->revprop_generation_file, path,
+ APR_READ | APR_WRITE, APR_OS_DEFAULT,
+ fs->pool));
+ }
+
+ return SVN_NO_ERROR;
+}
+
+/* Read revprop generation as stored on disk for repository FS. The result is
+ * returned in *CURRENT. Call only for repos that support revprop caching.
*/
static svn_error_t *
read_revprop_generation_file(apr_int64_t *current,
svn_fs_t *fs,
- apr_pool_t *pool)
+ apr_pool_t *scratch_pool)
{
- svn_error_t *err;
- apr_file_t *file;
+ fs_fs_data_t *ffd = fs->fsap_data;
char buf[80];
apr_size_t len;
- const char *path = svn_fs_fs__path_revprop_generation(fs, pool);
+ apr_off_t offset = 0;
- err = svn_io_file_open(&file, path,
- APR_READ | APR_BUFFERED,
- APR_OS_DEFAULT, pool);
- if (err && APR_STATUS_IS_ENOENT(err->apr_err))
- {
- svn_error_clear(err);
- *current = 2;
-
- return SVN_NO_ERROR;
- }
- SVN_ERR(err);
+ SVN_ERR(ensure_revprop_generation(fs, scratch_pool));
+ SVN_ERR(svn_io_file_seek(ffd->revprop_generation_file, APR_SET, &offset,
+ scratch_pool));
len = sizeof(buf);
- SVN_ERR(svn_io_read_length_line(file, buf, &len, pool));
+ SVN_ERR(svn_io_read_length_line(ffd->revprop_generation_file, buf, &len,
+ scratch_pool));
/* Check that the first line contains only digits. */
- SVN_ERR(svn_fs_fs__check_file_buffer_numeric(buf, 0, path,
- "Revprop Generation", pool));
+/* SVN_ERR(svn_fs_fs__check_file_buffer_numeric(buf, 0,
+ ffd->revprop_generation_file,
+ "Revprop Generation", pool));*/
SVN_ERR(svn_cstring_atoi64(current, buf));
- return svn_io_file_close(file, pool);
+ return SVN_NO_ERROR;
}
/* Write the CURRENT revprop generation to disk for repository FS.
+ * Call only for repos that support revprop caching.
*/
-svn_error_t *
-svn_fs_fs__write_revprop_generation_file(svn_fs_t *fs,
- apr_int64_t current,
- apr_pool_t *pool)
+static svn_error_t *
+write_revprop_generation_file(svn_fs_t *fs,
+ apr_int64_t current,
+ apr_pool_t *scratch_pool)
{
+ fs_fs_data_t *ffd = fs->fsap_data;
char buf[SVN_INT64_BUFFER_SIZE];
+ apr_off_t offset = 0;
+
apr_size_t len = svn__i64toa(buf, current);
buf[len] = '\n';
- SVN_ERR(svn_io_write_atomic(svn_fs_fs__path_revprop_generation(fs, pool),
- buf, len + 1,
- NULL /* copy_perms */, pool));
+ SVN_ERR(ensure_revprop_generation(fs, scratch_pool));
+ SVN_ERR(svn_io_file_seek(ffd->revprop_generation_file, APR_SET, &offset,
+ scratch_pool));
+ SVN_ERR(svn_io_file_write_full(ffd->revprop_generation_file, buf, len + 1,
+ NULL, scratch_pool));
+ SVN_ERR(svn_io_file_flush_to_disk(ffd->revprop_generation_file,
scratch_pool));
return SVN_NO_ERROR;
}
-/* Make sure the revprop_namespace member in FS is set. */
-static svn_error_t *
-ensure_revprop_namespace(svn_fs_t *fs)
-{
- fs_fs_data_t *ffd = fs->fsap_data;
-
- return ffd->revprop_namespace == NULL
- ? svn_atomic_namespace__create(&ffd->revprop_namespace,
- svn_dirent_join(fs->path,
- ATOMIC_REVPROP_NAMESPACE,
- fs->pool),
- fs->pool)
- : SVN_NO_ERROR;
-}
-
svn_error_t *
-svn_fs_fs__cleanup_revprop_namespace(svn_fs_t *fs)
-{
- const char *name = svn_dirent_join(fs->path,
- ATOMIC_REVPROP_NAMESPACE,
- fs->pool);
- return svn_error_trace(svn_atomic_namespace__cleanup(name, fs->pool));
-}
-
-/* Make sure the revprop_generation member in FS is set and, if necessary,
- * initialized with the latest value stored on disk.
- */
-static svn_error_t *
-ensure_revprop_generation(svn_fs_t *fs, apr_pool_t *pool)
+svn_fs_fs__reset_revprop_generation_file(svn_fs_t *fs,
+ apr_pool_t *scratch_pool)
{
fs_fs_data_t *ffd = fs->fsap_data;
+ const char *path = svn_fs_fs__path_revprop_generation(fs, scratch_pool);
- SVN_ERR(ensure_revprop_namespace(fs));
- if (ffd->revprop_generation == NULL)
+ /* Unconditionally close the revprop generation file.
+ * Don't care about FS formats. This ensures consistent internal state. */
+ if (ffd->revprop_generation_file)
{
- apr_int64_t current;
-
- SVN_ERR(svn_named_atomic__get(&ffd->revprop_generation,
- ffd->revprop_namespace,
- ATOMIC_REVPROP_GENERATION,
- TRUE));
-
- /* If the generation is at 0, we just created a new namespace
- * (it would be at least 2 otherwise). Read the latest generation
- * from disk and if we are the first one to initialize the atomic
- * (i.e. is still 0), set it to the value just gotten.
- */
- SVN_ERR(svn_named_atomic__read(¤t, ffd->revprop_generation));
- if (current == 0)
- {
- SVN_ERR(read_revprop_generation_file(¤t, fs, pool));
- SVN_ERR(svn_named_atomic__cmpxchg(NULL, current, 0,
- ffd->revprop_generation));
- }
+ SVN_ERR(svn_io_file_close(ffd->revprop_generation_file, scratch_pool));
+ ffd->revprop_generation_file = NULL;
}
- return SVN_NO_ERROR;
-}
+ /* Unconditionally remove any old revprop generation file.
+ * Don't care about FS formats. This ensures consistent on-disk state
+ * for old format repositories. */
+ SVN_ERR(svn_io_remove_file2(path, TRUE, scratch_pool));
-/* Make sure the revprop_timeout member in FS is set. */
-static svn_error_t *
-ensure_revprop_timeout(svn_fs_t *fs)
-{
- fs_fs_data_t *ffd = fs->fsap_data;
+ /* Write the initial revprop generation file contents, if supported by
+ * the current format. This ensures consistent on-disk state for new
+ * format repositories. */
+ if (ffd->format >= SVN_FS_FS__MIN_REVPROP_CACHING_FORMAT)
+ SVN_ERR(svn_io_write_atomic(path, "0\n", 2, NULL, scratch_pool));
- SVN_ERR(ensure_revprop_namespace(fs));
- return ffd->revprop_timeout == NULL
- ? svn_named_atomic__get(&ffd->revprop_timeout,
- ffd->revprop_namespace,
- ATOMIC_REVPROP_TIMEOUT,
- TRUE)
- : SVN_NO_ERROR;
+ /* ffd->revprop_generation_file will be re-opened on demand. */
+
+ return SVN_NO_ERROR;
}
/* Create an error object with the given MESSAGE and pass it to the
@@ -345,32 +323,22 @@ log_revprop_cache_init_warning(svn_fs_t
/* Test whether revprop cache and necessary infrastructure are
available in FS. */
static svn_boolean_t
-has_revprop_cache(svn_fs_t *fs, apr_pool_t *pool)
+has_revprop_cache(svn_fs_t *fs,
+ apr_pool_t *scratch_pool)
{
fs_fs_data_t *ffd = fs->fsap_data;
svn_error_t *error;
+ /* Supported by the FS format? */
+ if (ffd->format < SVN_FS_FS__MIN_REVPROP_CACHING_FORMAT)
+ return FALSE;
+
/* is the cache (still) enabled? */
if (ffd->revprop_cache == NULL)
return FALSE;
- /* is it efficient? */
- if (!svn_named_atomic__is_efficient())
- {
- /* access to it would be quite slow
- * -> disable the revprop cache for good
- */
- ffd->revprop_cache = NULL;
- log_revprop_cache_init_warning(fs, NULL,
- "Revprop caching for '%s' disabled"
- " because it would be inefficient.",
- pool);
-
- return FALSE;
- }
-
- /* try to access our SHM-backed infrastructure */
- error = ensure_revprop_generation(fs, pool);
+ /* try initialize our file-backed infrastructure */
+ error = ensure_revprop_generation(fs, scratch_pool);
if (error)
{
/* failure -> disable revprop cache for good */
@@ -378,9 +346,9 @@ has_revprop_cache(svn_fs_t *fs, apr_pool
ffd->revprop_cache = NULL;
log_revprop_cache_init_warning(fs, error,
"Revprop caching for '%s' disabled "
- "because SHM infrastructure for revprop "
+ "because infrastructure for revprop "
"caching failed to initialize.",
- pool);
+ scratch_pool);
return FALSE;
}
@@ -394,8 +362,8 @@ typedef struct revprop_generation_fixup_
/* revprop generation to read */
apr_int64_t *generation;
- /* containing the revprop_generation member to query */
- fs_fs_data_t *ffd;
+ /* file system context */
+ svn_fs_t *fs;
} revprop_generation_upgrade_t;
/* If the revprop generation has an odd value, it means the original writer
@@ -407,23 +375,28 @@ typedef struct revprop_generation_fixup_
*/
static svn_error_t *
revprop_generation_fixup(void *void_baton,
- apr_pool_t *pool)
+ apr_pool_t *scratch_pool)
{
revprop_generation_upgrade_t *baton = void_baton;
- assert(baton->ffd->has_write_lock);
+ fs_fs_data_t *ffd = baton->fs->fsap_data;
+ assert(ffd->has_write_lock);
/* Maybe, either the original revprop writer or some other reader has
already corrected / bumped the revprop generation. Thus, we need
- to read it again. */
- SVN_ERR(svn_named_atomic__read(baton->generation,
- baton->ffd->revprop_generation));
+ to read it again. However, we will now be the only ones changing
+ the file contents due to us holding the write lock. */
+ SVN_ERR(read_revprop_generation_file(baton->generation, baton->fs,
+ scratch_pool));
/* Cause everyone to re-read revprops upon their next access, if the
last revprop write did not complete properly. */
- while (*baton->generation % 2)
- SVN_ERR(svn_named_atomic__add(baton->generation,
- 1,
- baton->ffd->revprop_generation));
+ if (*baton->generation % 2)
+ {
+ ++*baton->generation;
+ SVN_ERR(write_revprop_generation_file(baton->fs,
+ *baton->generation,
+ scratch_pool));
+ }
return SVN_NO_ERROR;
}
@@ -434,42 +407,40 @@ revprop_generation_fixup(void *void_bato
static svn_error_t *
read_revprop_generation(apr_int64_t *generation,
svn_fs_t *fs,
- apr_pool_t *pool)
+ apr_pool_t *scratch_pool)
{
apr_int64_t current = 0;
fs_fs_data_t *ffd = fs->fsap_data;
/* read the current revprop generation number */
- SVN_ERR(ensure_revprop_generation(fs, pool));
- SVN_ERR(svn_named_atomic__read(¤t, ffd->revprop_generation));
+ SVN_ERR(read_revprop_generation_file(¤t, fs, scratch_pool));
/* is an unfinished revprop write under the way? */
if (current % 2)
{
- apr_int64_t timeout = 0;
-
- /* read timeout for the write operation */
- SVN_ERR(ensure_revprop_timeout(fs));
- SVN_ERR(svn_named_atomic__read(&timeout, ffd->revprop_timeout));
+ apr_time_t mtime;
+ SVN_ERR(svn_io_file_affected_time(&mtime,
+ svn_fs_fs__path_revprop_generation(fs, scratch_pool),
+ scratch_pool));
/* has the writer process been aborted,
* i.e. has the timeout been reached?
*/
- if (apr_time_now() > timeout)
+ if (apr_time_now() > mtime + REVPROP_CHANGE_TIMEOUT)
{
revprop_generation_upgrade_t baton;
baton.generation = ¤t;
- baton.ffd = ffd;
+ baton.fs = fs;
/* Ensure that the original writer process no longer exists by
* acquiring the write lock to this repository. Then, fix up
* the revprop generation.
*/
if (ffd->has_write_lock)
- SVN_ERR(revprop_generation_fixup(&baton, pool));
+ SVN_ERR(revprop_generation_fixup(&baton, scratch_pool));
else
SVN_ERR(svn_fs_fs__with_write_lock(fs, revprop_generation_fixup,
- &baton, pool));
+ &baton, scratch_pool));
}
}
@@ -478,64 +449,58 @@ read_revprop_generation(apr_int64_t *gen
return SVN_NO_ERROR;
}
-/* Set the revprop generation to the next odd number to indicate that
- there is a revprop write process under way. If that times out,
- readers shall recover from that state & re-read revprops.
- Use the access object in FS to set the shared mem value. */
+/* Set the revprop generation in FS to the next odd number to indicate
+ that there is a revprop write process under way. Return that value
+ in *GENERATION. If the change times out, readers shall recover from
+ that state & re-read revprops.
+ This is a no-op for repo formats that don't support revprop caching. */
static svn_error_t *
-begin_revprop_change(svn_fs_t *fs, apr_pool_t *pool)
+begin_revprop_change(apr_int64_t *generation,
+ svn_fs_t *fs,
+ apr_pool_t *scratch_pool)
{
- apr_int64_t current;
fs_fs_data_t *ffd = fs->fsap_data;
+ SVN_ERR_ASSERT(ffd->has_write_lock);
- /* set the timeout for the write operation */
- SVN_ERR(ensure_revprop_timeout(fs));
- SVN_ERR(svn_named_atomic__write(NULL,
- apr_time_now() + REVPROP_CHANGE_TIMEOUT,
- ffd->revprop_timeout));
+ /* Old format repositories don't have to worry about revprop caching. */
+ if (ffd->format < SVN_FS_FS__MIN_REVPROP_CACHING_FORMAT)
+ return SVN_NO_ERROR;
- /* set the revprop generation to an odd value to indicate
- * that a write is in progress
+ /* Set the revprop generation to an odd value to indicate
+ * that a write is in progress.
*/
- SVN_ERR(ensure_revprop_generation(fs, pool));
- do
- {
- SVN_ERR(svn_named_atomic__add(¤t,
- 1,
- ffd->revprop_generation));
- }
- while (current % 2 == 0);
+ SVN_ERR(read_revprop_generation(generation, fs, scratch_pool));
+ ++*generation;
+ SVN_ERR(write_revprop_generation_file(fs, *generation, scratch_pool));
return SVN_NO_ERROR;
}
-/* Set the revprop generation to the next even number to indicate that
+/* Set the revprop generation in FS to the next even generation after
+ the odd value in GENERATION to indicate that
a) readers shall re-read revprops, and
- b) the write process has been completed (no recovery required)
- Use the access object in FS to set the shared mem value. */
+ b) the write process has been completed (no recovery required).
+ This is a no-op for repo formats that don't support revprop caching. */
static svn_error_t *
-end_revprop_change(svn_fs_t *fs, apr_pool_t *pool)
+end_revprop_change(svn_fs_t *fs,
+ apr_int64_t generation,
+ apr_pool_t *scratch_pool)
{
- apr_int64_t current = 1;
fs_fs_data_t *ffd = fs->fsap_data;
+ SVN_ERR_ASSERT(ffd->has_write_lock);
+ SVN_ERR_ASSERT(generation % 2);
- /* set the revprop generation to an even value to indicate
- * that a write has been completed
- */
- SVN_ERR(ensure_revprop_generation(fs, pool));
- do
- {
- SVN_ERR(svn_named_atomic__add(¤t,
- 1,
- ffd->revprop_generation));
- }
- while (current % 2);
-
- /* Save the latest generation to disk. FS is currently in a "locked"
- * state such that we can be sure the be the only ones to write that
- * file.
+ /* Old format repositories don't have to worry about revprop caching. */
+ if (ffd->format < SVN_FS_FS__MIN_REVPROP_CACHING_FORMAT)
+ return SVN_NO_ERROR;
+
+ /* Set the revprop generation to an even value to indicate
+ * that a write has been completed. Since we held the write
+ * lock, nobody else could have updated the file contents.
*/
- return svn_fs_fs__write_revprop_generation_file(fs, current, pool);
+ SVN_ERR(write_revprop_generation_file(fs, generation + 1, scratch_pool));
+
+ return SVN_NO_ERROR;
}
/* Container for all data required to access the packed revprop file
@@ -1058,17 +1023,19 @@ switch_to_new_revprop(svn_fs_t *fs,
svn_boolean_t bump_generation,
apr_pool_t *pool)
{
+ apr_int64_t generation;
+
/* Now, we may actually be replacing revprops. Make sure that all other
threads and processes will know about this. */
if (bump_generation)
- SVN_ERR(begin_revprop_change(fs, pool));
+ SVN_ERR(begin_revprop_change(&generation, fs, pool));
SVN_ERR(svn_fs_fs__move_into_place(tmp_path, final_path, perms_reference,
pool));
/* Indicate that the update (if relevant) has been completed. */
if (bump_generation)
- SVN_ERR(end_revprop_change(fs, pool));
+ SVN_ERR(end_revprop_change(fs, generation, pool));
/* Clean up temporary files, if necessary. */
if (files_to_delete)
Modified:
subversion/branches/revprop-caching-ng/subversion/libsvn_fs_fs/revprops.h
URL:
http://svn.apache.org/viewvc/subversion/branches/revprop-caching-ng/subversion/libsvn_fs_fs/revprops.h?rev=1619857&r1=1619856&r2=1619857&view=diff
==============================================================================
--- subversion/branches/revprop-caching-ng/subversion/libsvn_fs_fs/revprops.h
(original)
+++ subversion/branches/revprop-caching-ng/subversion/libsvn_fs_fs/revprops.h
Fri Aug 22 16:18:06 2014
@@ -22,17 +22,15 @@
#include "svn_fs.h"
-/* Write the CURRENT revprop generation to disk for repository FS.
+/* Auto-create / replace the revprop generation file in FS with its
+ * initial contents, if supported by the format. Otherwise remove any
+ * left-over revprop generation files from e.g. 1.8.x. In any case,
+ * FS will not hold an open handle to it after this function succeeds.
*/
svn_error_t *
-svn_fs_fs__write_revprop_generation_file(svn_fs_t *fs,
- apr_int64_t current,
+svn_fs_fs__reset_revprop_generation_file(svn_fs_t *fs,
apr_pool_t *pool);
-/* Make sure the revprop_namespace member in FS is set. */
-svn_error_t *
-svn_fs_fs__cleanup_revprop_namespace(svn_fs_t *fs);
-
/* In the filesystem FS, pack all revprop shards up to min_unpacked_rev.
*
* NOTE: Keep the old non-packed shards around until after the format bump.
