First cut at a new io API, with an in-memory reference implementation + test case.

This commit is contained in:
Sears Russell 2006-10-13 04:39:03 +00:00
parent e961a2bdb8
commit 80a4148543
4 changed files with 708 additions and 1 deletions

85
lladd/io/handle.h Normal file
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@ -0,0 +1,85 @@
#include <lladd/transactional.h>
#define stasis_handle(x) stasis_handle_##x
/**
Error handling:
read, write, append, open, release_read_buffer and
release_write_buffer return 0 on success, and an error code
otherwise. read_buffer() and write_buffer() return error codes via
the error field of the handles they produce.
Errors in num_copies, num_copies_buffer, start_position, and end_position
are always unrecoverable, and return -1.
Here are the meanings of the various error codes:
EDOM off is less than the beginning of the file (possibly due to truncation).
EBADF an unrecoverable error occurred; the handle is no longer vaild. The error
that caused this one is stored in the handle's error field.
Handle implementations may return return other errors as appropriate.
*/
typedef struct stasis_handle_t {
/** @return the number of in-memory copies made when the caller
provides the buffer */
int (*num_copies)();
/** @return the number of in-memory copies made when the handle
provides the buffer */
int (*num_copies_buffer)();
int (*close)(struct stasis_handle_t *);
/** The offset of the handle's first byte */
lsn_t (*start_position)(struct stasis_handle_t * h);
/** The offset of the byte after the end of the handle's data. */
lsn_t (*end_position)(struct stasis_handle_t * h);
int (*write)(struct stasis_handle_t * h, lsn_t off,
const byte * dat, lsn_t len);
int (*append)(struct stasis_handle_t * h, lsn_t * off, const byte * dat, lsn_t len);
struct stasis_write_buffer_t * (*write_buffer)(struct stasis_handle_t * h,
lsn_t off, lsn_t len);
struct stasis_write_buffer_t * (*append_buffer)(struct stasis_handle_t * h,
lsn_t len);
int (*release_write_buffer)(struct stasis_write_buffer_t * w);
int (*read)(struct stasis_handle_t * h,
lsn_t offset, byte * buf, lsn_t length);
struct stasis_read_buffer_t * (*read_buffer)(struct stasis_handle_t * h,
lsn_t ofset, lsn_t length);
int (*release_read_buffer)(struct stasis_read_buffer_t * r);
int (*truncate_start)(struct stasis_handle_t * h, lsn_t new_start);
int error;
void * impl;
} stasis_handle_t;
typedef struct stasis_write_buffer_t {
stasis_handle_t * h;
lsn_t off;
byte * buf;
lsn_t len;
void * impl;
int error;
} stasis_write_buffer_t;
typedef struct stasis_read_buffer_t {
stasis_handle_t * h;
const byte * buf;
lsn_t len;
void * impl;
int error;
} stasis_read_buffer_t;
stasis_handle_t * stasis_handle(open_memory)();
stasis_handle_t * stasis_handle(open_file)(char * path, int mode);
stasis_handle_t * stasis_handle(open_non_blocking)(stasis_handle_t * h,
int worker_thread_count);
stasis_handle_t * stasis_handle(open_verifying)(stasis_handle_t * h);

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@ -17,7 +17,8 @@ liblladd_a_SOURCES=crc32.c redblack.c lhtable.c common.c stats.c io.c bufferMana
operations/naiveLinearHash.c operations/nestedTopActions.c \ operations/naiveLinearHash.c operations/nestedTopActions.c \
operations/linearHashNTA.c operations/linkedListNTA.c \ operations/linearHashNTA.c operations/linkedListNTA.c \
operations/pageOrientedListNTA.c operations/bTree.c \ operations/pageOrientedListNTA.c operations/bTree.c \
operations/regions.c operations/regions.c \
io/memory.c
# page/header.c logger/logMemory.c \ ringbuffer.c \ asdfas # page/header.c logger/logMemory.c \ ringbuffer.c \ asdfas
#operations/lladdhash.c #operations/lladdhash.c
#AM_CFLAGS= -g -Wall -pedantic -std=gnu99 #AM_CFLAGS= -g -Wall -pedantic -std=gnu99

273
src/lladd/io/memory.c Normal file
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#include <lladd/io/handle.h>
#include <latches.h>
#include <stdlib.h>
#include <assert.h>
#include <string.h>
#include <pthread.h>
#include <errno.h>
typedef struct mem_impl {
pthread_mutex_t mut;
rwl * trunc_latch;
lsn_t start_pos;
lsn_t end_pos;
byte * buf;
} mem_impl;
static int mem_num_copies() { return 1; }
static int mem_num_copies_buffer() { return 0; }
static int mem_close(stasis_handle_t * h) {
free(((mem_impl*)h->impl)->buf);
pthread_mutex_destroy(&(((mem_impl*)h->impl)->mut));
deletelock(((mem_impl*)h->impl)->trunc_latch);
free(h->impl);
free(h);
return 0;
}
static lsn_t mem_start_position(stasis_handle_t *h) {
lsn_t ret;
mem_impl* impl = (mem_impl*)(h->impl);
pthread_mutex_lock(&impl->mut);
ret = impl->start_pos;
pthread_mutex_unlock(&impl->mut);
return ret;
}
static lsn_t mem_end_position(stasis_handle_t *h) {
lsn_t ret;
mem_impl* impl = (mem_impl*)(h->impl);
pthread_mutex_lock(&impl->mut);
ret = impl->end_pos;
pthread_mutex_unlock(&impl->mut);
return ret;
}
static stasis_write_buffer_t * mem_write_buffer(stasis_handle_t * h,
lsn_t off, lsn_t len) {
mem_impl* impl = (mem_impl*)(h->impl);
stasis_write_buffer_t * ret = malloc(sizeof(stasis_write_buffer_t));
if(!ret) { return NULL; }
writelock(impl->trunc_latch,0);
pthread_mutex_lock(&(impl->mut));
int error = 0;
if(impl->start_pos > off) {
error = EDOM;
} else if(impl->end_pos > off+len) {
// Just need to return buffer; h's state is unchanged.
} else {
byte * newbuf = realloc(impl->buf, off+len - impl->start_pos);
if(newbuf) {
impl->buf = newbuf;
impl->end_pos = off+len;
} else {
error = ENOMEM;
}
}
if(error) {
ret->h = h;
ret->off = 0;
ret->buf = 0;
ret->len = 0;
ret->impl = 0;
ret->error = error;
} else {
ret->h = h;
ret->off = off;
ret->buf = &(impl->buf[off-impl->start_pos]);
ret->len = len;
ret->impl = 0;
ret->error = 0;
}
pthread_mutex_unlock(&(impl->mut));
return ret;
}
static stasis_write_buffer_t * mem_append_buffer(stasis_handle_t * h,
lsn_t len) {
mem_impl * impl = (mem_impl*)(h->impl);
stasis_write_buffer_t * ret = malloc(sizeof(stasis_write_buffer_t));
if(!ret) { return 0; }
writelock(impl->trunc_latch,0);
pthread_mutex_lock(&(impl->mut));
lsn_t off = impl->end_pos;
impl->end_pos += len;
byte * newbuf = realloc(impl->buf, impl->end_pos - impl->start_pos);
if(newbuf) {
impl->buf = newbuf;
ret->h = h;
ret->off = off;
ret->buf = &(impl->buf[off-impl->start_pos]);
ret->len = len;
ret->impl = 0;
ret->error = 0;
} else {
ret->h = h;
ret->off = 0;
ret->buf = 0;
ret->len = 0;
ret->impl = 0;
ret->error = ENOMEM;
}
pthread_mutex_unlock(&(impl->mut));
return ret;
}
static int mem_release_write_buffer(stasis_write_buffer_t * w) {
unlock(((mem_impl*)w->h->impl)->trunc_latch);
free(w);
return 0;
}
static int mem_write(stasis_handle_t * h, lsn_t off,
const byte * dat, lsn_t len) {
// Overlapping writes aren't atomic; no latch needed.
stasis_write_buffer_t * w = mem_write_buffer(h, off, len);
int ret;
if(w->error) {
ret = w->error;
} else {
memcpy(w->buf, dat, len);
ret = 0;
}
mem_release_write_buffer(w);
return ret;
}
static int mem_append(stasis_handle_t * h, lsn_t * off, const byte * dat, lsn_t len) {
stasis_write_buffer_t * w = mem_append_buffer(h, len);
int ret;
if(w->error) {
ret = w->error;
} else {
memcpy(w->buf, dat, len);
ret = 0;
}
*off = w->off;
mem_release_write_buffer(w);
return ret;
}
static stasis_read_buffer_t * mem_read_buffer(stasis_handle_t * h,
lsn_t off, lsn_t len) {
mem_impl * impl = (mem_impl*)(h->impl);
readlock(impl->trunc_latch,0);
pthread_mutex_lock(&(impl->mut));
stasis_read_buffer_t * ret = malloc(sizeof(stasis_read_buffer_t));
if(!ret) { return NULL; }
if(off < impl->start_pos || off + len > impl->end_pos) {
ret->h = h;
ret->buf = 0;
ret->len = 0;
ret->impl = 0;
ret->error = EDOM;
} else {
ret->h = h;
ret->buf = &(impl->buf[off-impl->start_pos]);
ret->len = len;
ret->impl = 0;
ret->error = 0;
}
pthread_mutex_unlock(&(impl->mut));
return ret;
}
static int mem_release_read_buffer(stasis_read_buffer_t * r) {
unlock(((mem_impl*)r->h->impl)->trunc_latch);
free(r);
return 0;
}
static int mem_read(stasis_handle_t * h,
lsn_t off, byte * buf, lsn_t len) {
stasis_read_buffer_t * r = mem_read_buffer(h, off, len);
int ret;
if(r->error) {
ret = r->error;
} else {
memcpy(buf, r->buf, len);
ret = 0;
}
mem_release_read_buffer(r);
return ret;
}
static int mem_truncate_start(stasis_handle_t * h, lsn_t new_start) {
mem_impl* impl = (mem_impl*) h->impl;
writelock(impl->trunc_latch,0);
pthread_mutex_lock(&(impl->mut));
if(new_start < impl->start_pos) {
pthread_mutex_unlock(&impl->mut);
unlock(impl->trunc_latch);
return 0;
}
if(new_start > impl->end_pos) {
pthread_mutex_unlock(&impl->mut);
unlock(impl->trunc_latch);
return EDOM;
}
byte * new_buf = malloc(impl->end_pos -new_start);
memcpy(new_buf, &(impl->buf[new_start - impl->start_pos]), impl->end_pos - new_start);
free(impl->buf);
impl->buf = new_buf;
impl->start_pos = new_start;
pthread_mutex_unlock(&(impl->mut));
unlock(impl->trunc_latch);
return 0;
}
struct stasis_handle_t mem_func = {
.num_copies = mem_num_copies,
.num_copies_buffer = mem_num_copies_buffer,
.close = mem_close,
.start_position = mem_start_position,
.end_position = mem_end_position,
.write = mem_write,
.append = mem_append,
.write_buffer = mem_write_buffer,
.append_buffer = mem_append_buffer,
.release_write_buffer = mem_release_write_buffer,
.read = mem_read,
.read_buffer = mem_read_buffer,
.release_read_buffer = mem_release_read_buffer,
.truncate_start = mem_truncate_start,
.error = 0
};
stasis_handle_t * stasis_handle(open_memory)() {
stasis_handle_t * ret = malloc(sizeof(stasis_handle_t));
*ret = mem_func;
mem_impl * impl = malloc(sizeof(mem_impl));
ret->impl = impl;
pthread_mutex_init(&(impl->mut), 0);
impl->trunc_latch = initlock();
impl->start_pos = 0;
impl->end_pos = 0;
impl->buf = malloc(0);
return ret;
}

348
test/lladd/check_io.c Normal file
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@ -0,0 +1,348 @@
/*--- This software is copyrighted by the Regents of the University of
California, and other parties. The following terms apply to all files
associated with the software unless explicitly disclaimed in
individual files.
The authors hereby grant permission to use, copy, modify, distribute,
and license this software and its documentation for any purpose,
provided that existing copyright notices are retained in all copies
and that this notice is included verbatim in any distributions. No
written agreement, license, or royalty fee is required for any of the
authorized uses. Modifications to this software may be copyrighted by
their authors and need not follow the licensing terms described here,
provided that the new terms are clearly indicated on the first page of
each file where they apply.
IN NO EVENT SHALL THE AUTHORS OR DISTRIBUTORS BE LIABLE TO ANY PARTY
FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
ARISING OUT OF THE USE OF THIS SOFTWARE, ITS DOCUMENTATION, OR ANY
DERIVATIVES THEREOF, EVEN IF THE AUTHORS HAVE BEEN ADVISED OF THE
POSSIBILITY OF SUCH DAMAGE.
THE AUTHORS AND DISTRIBUTORS SPECIFICALLY DISCLAIM ANY WARRANTIES,
INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND
NON-INFRINGEMENT. THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, AND
THE AUTHORS AND DISTRIBUTORS HAVE NO OBLIGATION TO PROVIDE
MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
GOVERNMENT USE: If you are acquiring this software on behalf of the
U.S. government, the Government shall have only "Restricted Rights" in
the software and related documentation as defined in the Federal
Acquisition Regulations (FARs) in Clause 52.227.19 (c) (2). If you are
acquiring the software on behalf of the Department of Defense, the
software shall be classified as "Commercial Computer Software" and the
Government shall have only "Restricted Rights" as defined in Clause
252.227-7013 (c) (1) of DFARs. Notwithstanding the foregoing, the
authors grant the U.S. Government and others acting in its behalf
permission to use and distribute the software in accordance with the
terms specified in this license.
---*/
#include <config.h>
#include <lladd/io/handle.h>
#include <check.h>
#include <assert.h>
#include "../check_includes.h"
#define LOG_NAME "check_io.log"
long myrandom(long x) {
double xx = x;
double r = random();
double max = ((long)RAND_MAX)+1;
max /= xx;
return (long)((r/max));
}
void handle_smoketest(stasis_handle_t * h) {
const int one = 0x11111111;
const int two = 0x22222222;
const int three = 0x33333333;
const int four = 0x44444444;
assert((!h->num_copies()) || (!h->num_copies_buffer()));
assert(0 == h->start_position(h) ||
0 == h->end_position(h));
assert(! h->write(h, 0, (byte*)&one, sizeof(int)));
int one_read = 0;
assert(! h->read(h, 0, (byte*)&one_read, sizeof(int)));
assert(one_read == one);
stasis_write_buffer_t * w = h->write_buffer(h, sizeof(int), sizeof(int));
*((int*)(w->buf)) = two;
w->h->release_write_buffer(w);
one_read = 0;
stasis_read_buffer_t * r = h->read_buffer(h, 0, sizeof(int));
one_read = *((int*)(r->buf));
r->h->release_read_buffer(r);
assert(one == one_read);
int two_read = 0;
assert(! h->read(h, sizeof(int), (byte*)&two_read, sizeof(int)));
assert(two == two_read);
lsn_t off;
assert(! h->append(h, &off, (byte*)&three, sizeof(int)));
w = h->append_buffer(h, sizeof(int));
memcpy(w->buf, &four, sizeof(int));
w->h->release_write_buffer(w);
h->truncate_start(h, 2 * sizeof(int));
int three_read = 0;
int four_read = 0;
assert(! h->read(h, 2*sizeof(int), (byte*)&three_read, sizeof(int)));
r = h->read_buffer(h, 3*sizeof(int), sizeof(int));
memcpy(&four_read, r->buf, sizeof(int));
r->h->release_read_buffer(r);
assert(three == three_read);
assert(four == four_read);
}
typedef struct {
int * values;
int count;
stasis_handle_t * h;
} thread_arg;
#define VALUE_COUNT 100000
#define THREAD_COUNT 100
#define OPS_PER_THREAD 500000
lsn_t trunc_val;
pthread_mutex_t trunc_mut = PTHREAD_MUTEX_INITIALIZER;
void load_handle(thread_arg* t) {
lsn_t * offsets = malloc(t->count * sizeof(lsn_t));
stasis_handle_t * h = t->h;
for(int i = 0; i < t->count; i++) {
offsets[i] = -1;
}
for(int i = 0; i < OPS_PER_THREAD; i++) {
int val = myrandom(t->count);
if(offsets[val] == -1) {
// Need to write it somewhere.
long choice = myrandom(4);
switch(choice) {
case 0: { // overwrite old entry with write()
long val2 = myrandom(t->count);
offsets[val] = offsets[val2];
offsets[val2] = -1;
if(offsets[val] != -1) {
int ret = h->write(h, offsets[val], (const byte*)&(t->values[val]), sizeof(int));
if(ret) {
assert(ret == EDOM);
offsets[val] = -1;
i--;
}
} else {
i--;
}
} break;
case 1: { // overwrite old entry with write_buffer()
long val2 = myrandom(t->count);
offsets[val] = offsets[val2];
offsets[val2] = -1;
if(offsets[val] != -1) {
stasis_write_buffer_t * w = h->write_buffer(h, offsets[val], sizeof(int));
if(!w->error) {
*((int*)w->buf) = t->values[val];
assert(w->len == sizeof(int));
assert(w->off == offsets[val]);
} else {
assert(w->error == EDOM);
offsets[val] = -1;
i--;
}
w->h->release_write_buffer(w);
} else {
i--;
}
} break;
case 2: { // append
int ret = h->append(h, &(offsets[val]), (const byte*)&(t->values[val]), sizeof(int));
assert(!ret);
} break;
case 3: { // append_buffer
stasis_write_buffer_t * w = h->append_buffer(h, sizeof(int));
if(!w->error) {
*((int*)w->buf) = t->values[val];
assert(w->len == sizeof(int));
offsets[val] = w->off;
} else {
abort();
}
w->h->release_write_buffer(w);
} break;
default: {
abort();
}
}
int check;
int ret = h->read(h, offsets[val], (byte*)&check, sizeof(int));
if(!ret) {
assert(check == t->values[val]);
}
} else {
// Read the value.
long choice = myrandom(2);
switch(choice) {
case 0: { // read
int j;
int ret = h->read(h, offsets[val], (byte*)&j, sizeof(int));
if(!ret) {
assert(j == t->values[val]);
} else {
assert(ret == EDOM);
assert(h->start_position(h) > offsets[val]);
}
} break;
case 1: { // read_buffer
stasis_read_buffer_t * r = h->read_buffer(h, offsets[val], sizeof(int));
if(!r->error) {
assert(*(int*)(r->buf) == t->values[val]);
assert(r->len == sizeof(int));
} else {
assert(r->error == EDOM);
assert(h->start_position(h) > offsets[val]);
}
r->h->release_read_buffer(r);
} break;
default:
abort();
};
}
// Truncate 1% of the time.
if(!myrandom(100)) {
lsn_t pre_start = h->start_position(h);
pthread_mutex_lock(&trunc_mut);
lsn_t start = trunc_val;
lsn_t stop = start - 100 + myrandom(200);
if(stop > trunc_val) {
trunc_val = stop;
}
pthread_mutex_unlock(&trunc_mut);
assert(pre_start <= start);
int ret = h->truncate_start(h, stop);
if(!ret) {
lsn_t post_stop = h->start_position(h);
assert(stop <= post_stop);
}
}
}
free(offsets);
}
void handle_sequentialtest(stasis_handle_t * h) {
time_t seed = time(0);
printf("\nSeed = %ld\n", seed);
srandom(seed);
int * values = malloc(VALUE_COUNT * sizeof(int));
for(int i = 0; i < VALUE_COUNT; i++) {
values[i] = i;
}
trunc_val = 0;
thread_arg arg = { values, VALUE_COUNT, h};
load_handle(&arg);
free(values);
}
void handle_concurrencytest(stasis_handle_t * h) {
int vc = myrandom(VALUE_COUNT) + 10;
printf("Running concurrency test with %d values", vc);
int * values = malloc(vc * sizeof(int));
for(int i = 0; i < vc; i++) {
values[i] = i;
}
thread_arg * args = malloc(THREAD_COUNT * sizeof(thread_arg));
pthread_t * threads = malloc(THREAD_COUNT * sizeof(pthread_t));
int val_per_thread = vc / THREAD_COUNT;
trunc_val = 0;
for(int i = 0; i < THREAD_COUNT; i++) {
args[i].values = &(values[i * val_per_thread]);
args[i].count = val_per_thread;
args[i].h = h;
pthread_create(&threads[i], 0, (void*(*)(void*))load_handle, &args[i]);
}
for(int i = 0; i < THREAD_COUNT; i++) {
pthread_join(threads[i], 0);
}
free(values);
free(args);
free(threads);
}
/**
@test
Check the memory I/O handle.
*/
START_TEST(io_memoryTest) {
stasis_handle_t * h = stasis_handle(open_memory)(0);
handle_smoketest(h);
h->close(h);
h = stasis_handle(open_memory)(0);
handle_sequentialtest(h);
h->close(h);
h = stasis_handle(open_memory)(0);
handle_concurrencytest(h);
h->close(h);
} END_TEST
/**
Add suite declarations here
*/
Suite * check_suite(void) {
Suite *s = suite_create("io");
/* Begin a new test */
TCase *tc = tcase_create("io_test");
tcase_set_timeout(tc, 600); // ten minute timeout
/* Sub tests are added, one per line, here */
tcase_add_test(tc, io_memoryTest);
/* --------------------------------------------- */
tcase_add_checked_fixture(tc, setup, teardown);
suite_add_tcase(s, tc);
return s;
}
#include "../check_setup.h"