Haiku/haiku
Haiku/haiku
1
0
Fork 0
mirror of https://review.haiku-os.org/haiku synced 2025-01-18 04:28:52 +01:00
Code Issues Actions Packages Projects Releases Wiki Activity

ramfs: Read multiple dirents in read_dir() at once.

Browse Source 
Massively cuts down on syscall count when reading directories.
This commit is contained in:
Augustin Cavalier 2025-01-14 19:10:12 -05:00
parent eab4f99826
commit 0f63c097ac
1 changed files with 59 additions and 47 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

106
src/add-ons/kernel/file_systems/ramfs/kernel_interface.cpp
View File

@ -1116,27 +1116,32 @@ public:
DirectoryCookie(Directory *directory = NULL)
:
fIterator(directory),
fDotIndex(DOT_INDEX),
// debugging
fIteratorID(atomic_add(&fNextIteratorID, 1)),
fGetNextCounter(0)
fDotIndex(DOT_INDEX)
{
}
void Unset() { fIterator.Unset(); }
// EntryIterator *GetIterator() const { return &fIterator; }
status_t GetNext(ino_t *nodeID, const char **entryName)
status_t Next()
{
status_t error = B_OK;
if (fDotIndex < ENTRY_INDEX)
fDotIndex++;
if (fDotIndex == ENTRY_INDEX) {
Entry* entry = NULL;
error = fIterator.GetNext(&entry);
}
return error;
}
status_t GetCurrent(ino_t *nodeID, const char **entryName)
{
fGetNextCounter++;
status_t error = B_OK;
if (fDotIndex == DOT_INDEX) {
// "."
Node *entry = fIterator.GetDirectory();
*nodeID = entry->GetID();
*entryName = ".";
fDotIndex++;
} else if (fDotIndex == DOT_DOT_INDEX) {
// ".."
Directory *dir = fIterator.GetDirectory();
@ -1145,19 +1150,20 @@ fGetNextCounter++;
else
*nodeID = dir->GetID();
*entryName = "..";
fDotIndex++;
} else {
// ordinary entries
Entry *entry = NULL;
error = fIterator.GetNext(&entry);
Entry *entry = fIterator.GetCurrent();
if (entry == NULL)
error = B_ENTRY_NOT_FOUND;
if (error == B_OK) {
*nodeID = entry->GetNode()->GetID();
*entryName = entry->GetName();
}
}
PRINT("EntryIterator %" B_PRId32 ", GetNext() counter: %" B_PRId32 ", entry: %p (%lld)\n",
fIteratorID, fGetNextCounter, fIterator.GetCurrent(),
(fIterator.GetCurrent()
PRINT("EntryIterator<%p>::GetNext(): entry: %p (%" B_PRIdINO ")\n",
this, fIterator.GetCurrent(),
(fIterator.GetCurrent() != NULL
? fIterator.GetCurrent()->GetNode()->GetID() : -1));
return error;
}
@ -1181,17 +1187,9 @@ private:
private:
EntryIterator fIterator;
uint32 fDotIndex;
// debugging
int32 fIteratorID;
int32 fGetNextCounter;
static int32 fNextIteratorID;
};
int32 DirectoryCookie::fNextIteratorID = 0;
static status_t
ramfs_create_dir(fs_volume* _volume, fs_vnode* _dir, const char *name, int mode)
{
@ -1359,7 +1357,7 @@ ramfs_free_dir_cookie(fs_volume* /*fs*/, fs_vnode* /*_node*/, void* _cookie)
static status_t
ramfs_read_dir(fs_volume* _volume, fs_vnode* DARG(_node), void* _cookie,
struct dirent *buffer, size_t bufferSize, uint32 *count)
struct dirent *dirent, size_t bufferSize, uint32 *_num)
{
FUNCTION_START();
Volume* volume = (Volume*)_volume->private_volume;
@ -1372,34 +1370,48 @@ ramfs_read_dir(fs_volume* _volume, fs_vnode* DARG(_node), void* _cookie,
if (!locker.IsLocked())
RETURN_ERROR(B_ERROR);
status_t error = cookie->Resume();
if (error == B_OK) {
// read one entry
status_t status = cookie->Resume();
if (status != B_OK)
RETURN_ERROR(status);
uint32 maxCount = *_num;
uint32 count = 0;
while (count < maxCount && bufferSize > sizeof(struct dirent)) {
size_t length = bufferSize - offsetof(struct dirent, d_name);
ino_t nodeID = -1;
const char *name = NULL;
if (cookie->GetNext(&nodeID, &name) == B_OK) {
PRINT(" entry: `%s'\n", name);
size_t nameLen = strlen(name);
// check, whether the entry fits into the buffer,
// and fill it in
size_t length = (buffer->d_name + nameLen + 1) - (char*)buffer;
if (length <= bufferSize) {
buffer->d_dev = volume->GetID();
buffer->d_ino = nodeID;
memcpy(buffer->d_name, name, nameLen);
buffer->d_name[nameLen] = '\0';
buffer->d_reclen = length;
*count = 1;
} else {
SET_ERROR(error, B_BUFFER_OVERFLOW);
}
} else
*count = 0;
if (cookie->GetCurrent(&nodeID, &name) != B_OK)
break;
cookie->Suspend();
PRINT(" entry: `%s'\n", name);
size_t nameLength = strlen(name);
if (length < (nameLength + 1)) {
// the remaining name buffer length is too small
if (count == 0)
RETURN_ERROR(B_BUFFER_OVERFLOW);
break;
}
length = nameLength;
dirent->d_dev = volume->GetID();
dirent->d_ino = nodeID;
memcpy(dirent->d_name, name, nameLength);
dirent->d_name[nameLength] = '\0';
dirent = next_dirent(dirent, length, bufferSize);
count++;
if (cookie->Next() != B_OK)
break;
}
RETURN_ERROR(error);
cookie->Suspend();
*_num = count;
return B_OK;
}