test_slru.c File Reference

#include "postgres.h"
#include "access/slru.h"
#include "access/transam.h"
#include "miscadmin.h"
#include "storage/fd.h"
#include "storage/ipc.h"
#include "storage/shmem.h"
#include "utils/builtins.h"

Include dependency graph for test_slru.c:

Go to the source code of this file.

Macros
#define	NUM_TEST_BUFFERS   16
#define	TestSLRULock   (&TestSLRULock)
#define	TestSlruCtl   (&TestSlruCtlData)

Functions
	PG_FUNCTION_INFO_V1 (test_slru_page_write)
	PG_FUNCTION_INFO_V1 (test_slru_page_writeall)
	PG_FUNCTION_INFO_V1 (test_slru_page_read)
	PG_FUNCTION_INFO_V1 (test_slru_page_readonly)
	PG_FUNCTION_INFO_V1 (test_slru_page_exists)
	PG_FUNCTION_INFO_V1 (test_slru_page_sync)
	PG_FUNCTION_INFO_V1 (test_slru_page_delete)
	PG_FUNCTION_INFO_V1 (test_slru_page_truncate)
	PG_FUNCTION_INFO_V1 (test_slru_delete_all)
static bool	test_slru_scan_cb (SlruCtl ctl, char *filename, int segpage, void *data)
Datum	test_slru_page_write (PG_FUNCTION_ARGS)
Datum	test_slru_page_writeall (PG_FUNCTION_ARGS)
Datum	test_slru_page_read (PG_FUNCTION_ARGS)
Datum	test_slru_page_readonly (PG_FUNCTION_ARGS)
Datum	test_slru_page_exists (PG_FUNCTION_ARGS)
Datum	test_slru_page_sync (PG_FUNCTION_ARGS)
Datum	test_slru_page_delete (PG_FUNCTION_ARGS)
Datum	test_slru_page_truncate (PG_FUNCTION_ARGS)
Datum	test_slru_delete_all (PG_FUNCTION_ARGS)
static void	test_slru_shmem_request (void)
static bool	test_slru_page_precedes_logically (int page1, int page2)
static void	test_slru_shmem_startup (void)
void	_PG_init (void)

Variables
	PG_MODULE_MAGIC
LWLock	TestSLRULock
static SlruCtlData	TestSlruCtlData
static shmem_request_hook_type	prev_shmem_request_hook = NULL
static shmem_startup_hook_type	prev_shmem_startup_hook = NULL

Macro Definition Documentation

NUM_TEST_BUFFERS

#define NUM_TEST_BUFFERS   16

Definition at line 41 of file test_slru.c.

TestSlruCtl

#define TestSlruCtl   (&TestSlruCtlData)

Definition at line 48 of file test_slru.c.

TestSLRULock

#define TestSLRULock   (&TestSLRULock)

Definition at line 45 of file test_slru.c.

Function Documentation

_PG_init()

void _PG_init

(

void

)

Definition at line 240 of file test_slru.c.

{
    if (!process_shared_preload_libraries_in_progress)
        ereport(ERROR,
                (errmsg("cannot load \"%s\" after startup", "test_slru"),
                 errdetail("\"%s\" must be loaded with shared_preload_libraries.",
                           "test_slru")));
 
    prev_shmem_request_hook = shmem_request_hook;
    shmem_request_hook = test_slru_shmem_request;
 
    prev_shmem_startup_hook = shmem_startup_hook;
    shmem_startup_hook = test_slru_shmem_startup;
}

References ereport, errdetail(), errmsg(), ERROR, prev_shmem_request_hook, prev_shmem_startup_hook, process_shared_preload_libraries_in_progress, shmem_request_hook, shmem_startup_hook, test_slru_shmem_request(), and test_slru_shmem_startup().

PG_FUNCTION_INFO_V1() [1/9]

PG_FUNCTION_INFO_V1

(

test_slru_delete_all

)

PG_FUNCTION_INFO_V1() [2/9]

PG_FUNCTION_INFO_V1

(

test_slru_page_delete

)

PG_FUNCTION_INFO_V1() [3/9]

PG_FUNCTION_INFO_V1

(

test_slru_page_exists

)

PG_FUNCTION_INFO_V1() [4/9]

PG_FUNCTION_INFO_V1

(

test_slru_page_read

)

PG_FUNCTION_INFO_V1() [5/9]

PG_FUNCTION_INFO_V1

(

test_slru_page_readonly

)

PG_FUNCTION_INFO_V1() [6/9]

PG_FUNCTION_INFO_V1

(

test_slru_page_sync

)

PG_FUNCTION_INFO_V1() [7/9]

PG_FUNCTION_INFO_V1

(

test_slru_page_truncate

)

PG_FUNCTION_INFO_V1() [8/9]

PG_FUNCTION_INFO_V1

(

test_slru_page_write

)

PG_FUNCTION_INFO_V1() [9/9]

PG_FUNCTION_INFO_V1

(

test_slru_page_writeall

)

test_slru_delete_all()

Datum test_slru_delete_all

(

PG_FUNCTION_ARGS

)

Definition at line 185 of file test_slru.c.

{
    /* this calls SlruScanDirCbDeleteAll() internally, ensuring deletion */
    SlruScanDirectory(TestSlruCtl, test_slru_scan_cb, NULL);
 
    PG_RETURN_VOID();
}

References PG_RETURN_VOID, SlruScanDirectory(), test_slru_scan_cb(), and TestSlruCtl.

test_slru_page_delete()

Datum test_slru_page_delete

(

PG_FUNCTION_ARGS

)

Definition at line 162 of file test_slru.c.

{
    int         pageno = PG_GETARG_INT32(0);
    FileTag     ftag;
 
    ftag.segno = pageno / SLRU_PAGES_PER_SEGMENT;
    SlruDeleteSegment(TestSlruCtl, ftag.segno);
 
    elog(NOTICE, "Called SlruDeleteSegment() for segment %u", ftag.segno);
 
    PG_RETURN_VOID();
}

References elog(), NOTICE, PG_GETARG_INT32, PG_RETURN_VOID, FileTag::segno, SLRU_PAGES_PER_SEGMENT, SlruDeleteSegment(), and TestSlruCtl.

test_slru_page_exists()

Datum test_slru_page_exists

(

PG_FUNCTION_ARGS

)

Definition at line 132 of file test_slru.c.

{
    int         pageno = PG_GETARG_INT32(0);
    bool        found;
 
    LWLockAcquire(TestSLRULock, LW_EXCLUSIVE);
    found = SimpleLruDoesPhysicalPageExist(TestSlruCtl, pageno);
    LWLockRelease(TestSLRULock);
 
    PG_RETURN_BOOL(found);
}

References LW_EXCLUSIVE, LWLockAcquire(), LWLockRelease(), PG_GETARG_INT32, PG_RETURN_BOOL, SimpleLruDoesPhysicalPageExist(), TestSlruCtl, and TestSLRULock.

test_slru_page_precedes_logically()

static bool test_slru_page_precedes_logically ( int  page1, int  page2  )

static

Definition at line 208 of file test_slru.c.

{
    return page1 < page2;
}

Referenced by test_slru_shmem_startup().

test_slru_page_read()

Datum test_slru_page_read

(

PG_FUNCTION_ARGS

)

Definition at line 96 of file test_slru.c.

{
    int         pageno = PG_GETARG_INT32(0);
    bool        write_ok = PG_GETARG_BOOL(1);
    char       *data = NULL;
    int         slotno;
 
    /* find page in buffers, reading it if necessary */
    LWLockAcquire(TestSLRULock, LW_EXCLUSIVE);
    slotno = SimpleLruReadPage(TestSlruCtl, pageno,
                               write_ok, InvalidTransactionId);
    data = (char *) TestSlruCtl->shared->page_buffer[slotno];
    LWLockRelease(TestSLRULock);
 
    PG_RETURN_TEXT_P(cstring_to_text(data));
}

References cstring_to_text(), data, InvalidTransactionId, LW_EXCLUSIVE, LWLockAcquire(), LWLockRelease(), PG_GETARG_BOOL, PG_GETARG_INT32, PG_RETURN_TEXT_P, SimpleLruReadPage(), TestSlruCtl, and TestSLRULock.

test_slru_page_readonly()

Datum test_slru_page_readonly

(

PG_FUNCTION_ARGS

)

Definition at line 114 of file test_slru.c.

{
    int         pageno = PG_GETARG_INT32(0);
    char       *data = NULL;
    int         slotno;
 
    /* find page in buffers, reading it if necessary */
    slotno = SimpleLruReadPage_ReadOnly(TestSlruCtl,
                                        pageno,
                                        InvalidTransactionId);
    Assert(LWLockHeldByMe(TestSLRULock));
    data = (char *) TestSlruCtl->shared->page_buffer[slotno];
    LWLockRelease(TestSLRULock);
 
    PG_RETURN_TEXT_P(cstring_to_text(data));
}

References Assert(), cstring_to_text(), data, InvalidTransactionId, LWLockHeldByMe(), LWLockRelease(), PG_GETARG_INT32, PG_RETURN_TEXT_P, SimpleLruReadPage_ReadOnly(), TestSlruCtl, and TestSLRULock.

test_slru_page_sync()

Datum test_slru_page_sync

(

PG_FUNCTION_ARGS

)

Definition at line 145 of file test_slru.c.

{
    int         pageno = PG_GETARG_INT32(0);
    FileTag     ftag;
    char        path[MAXPGPATH];
 
    /* note that this flushes the full file a segment is located in */
    ftag.segno = pageno / SLRU_PAGES_PER_SEGMENT;
    SlruSyncFileTag(TestSlruCtl, &ftag, path);
 
    elog(NOTICE, "Called SlruSyncFileTag() for segment %u on path %s",
         ftag.segno, path);
 
    PG_RETURN_VOID();
}

References elog(), MAXPGPATH, NOTICE, PG_GETARG_INT32, PG_RETURN_VOID, FileTag::segno, SLRU_PAGES_PER_SEGMENT, SlruSyncFileTag(), and TestSlruCtl.

test_slru_page_truncate()

Datum test_slru_page_truncate

(

PG_FUNCTION_ARGS

)

Definition at line 176 of file test_slru.c.

{
    int         pageno = PG_GETARG_INT32(0);
 
    SimpleLruTruncate(TestSlruCtl, pageno);
    PG_RETURN_VOID();
}

References PG_GETARG_INT32, PG_RETURN_VOID, SimpleLruTruncate(), and TestSlruCtl.

test_slru_page_write()

Datum test_slru_page_write

(

PG_FUNCTION_ARGS

)

Definition at line 61 of file test_slru.c.

{
    int         pageno = PG_GETARG_INT32(0);
    char       *data = text_to_cstring(PG_GETARG_TEXT_PP(1));
    int         slotno;
 
    LWLockAcquire(TestSLRULock, LW_EXCLUSIVE);
 
    slotno = SimpleLruZeroPage(TestSlruCtl, pageno);
 
    /* these should match */
    Assert(TestSlruCtl->shared->page_number[slotno] == pageno);
 
    /* mark the page as dirty so as it would get written */
    TestSlruCtl->shared->page_dirty[slotno] = true;
    TestSlruCtl->shared->page_status[slotno] = SLRU_PAGE_VALID;
 
    /* write given data to the page, up to the limit of the page */
    strncpy(TestSlruCtl->shared->page_buffer[slotno], data,
            BLCKSZ - 1);
 
    SimpleLruWritePage(TestSlruCtl, slotno);
    LWLockRelease(TestSLRULock);
 
    PG_RETURN_VOID();
}

References Assert(), data, LW_EXCLUSIVE, LWLockAcquire(), LWLockRelease(), PG_GETARG_INT32, PG_GETARG_TEXT_PP, PG_RETURN_VOID, SimpleLruWritePage(), SimpleLruZeroPage(), SLRU_PAGE_VALID, TestSlruCtl, TestSLRULock, and text_to_cstring().

test_slru_page_writeall()

Datum test_slru_page_writeall

(

PG_FUNCTION_ARGS

)

Definition at line 89 of file test_slru.c.

{
    SimpleLruWriteAll(TestSlruCtl, true);
    PG_RETURN_VOID();
}

References PG_RETURN_VOID, SimpleLruWriteAll(), and TestSlruCtl.

test_slru_scan_cb()

static bool test_slru_scan_cb ( SlruCtl  ctl, char *  filename, int  segpage, void *  data  )

static

Definition at line 54 of file test_slru.c.

{
    elog(NOTICE, "Calling test_slru_scan_cb()");
    return SlruScanDirCbDeleteAll(ctl, filename, segpage, data);
}

References data, elog(), filename, NOTICE, and SlruScanDirCbDeleteAll().

Referenced by test_slru_delete_all().

test_slru_shmem_request()

static void test_slru_shmem_request ( void  )

static

Definition at line 198 of file test_slru.c.

{
    if (prev_shmem_request_hook)
        prev_shmem_request_hook();
 
    /* reserve shared memory for the test SLRU */
    RequestAddinShmemSpace(SimpleLruShmemSize(NUM_TEST_BUFFERS, 0));
}

References NUM_TEST_BUFFERS, prev_shmem_request_hook, RequestAddinShmemSpace(), and SimpleLruShmemSize().

Referenced by _PG_init().

test_slru_shmem_startup()

static void test_slru_shmem_startup ( void  )

static

Definition at line 214 of file test_slru.c.

{
    const char  slru_dir_name[] = "pg_test_slru";
    int         test_tranche_id;
 
    if (prev_shmem_startup_hook)
        prev_shmem_startup_hook();
 
    /*
     * Create the SLRU directory if it does not exist yet, from the root of
     * the data directory.
     */
    (void) MakePGDirectory(slru_dir_name);
 
    /* initialize the SLRU facility */
    test_tranche_id = LWLockNewTrancheId();
    LWLockRegisterTranche(test_tranche_id, "test_slru_tranche");
    LWLockInitialize(TestSLRULock, test_tranche_id);
 
    TestSlruCtl->PagePrecedes = test_slru_page_precedes_logically;
    SimpleLruInit(TestSlruCtl, "TestSLRU",
                  NUM_TEST_BUFFERS, 0, TestSLRULock, slru_dir_name,
                  test_tranche_id, SYNC_HANDLER_NONE);
}

References LWLockInitialize(), LWLockNewTrancheId(), LWLockRegisterTranche(), MakePGDirectory(), NUM_TEST_BUFFERS, prev_shmem_startup_hook, SimpleLruInit(), SYNC_HANDLER_NONE, test_slru_page_precedes_logically(), TestSlruCtl, and TestSLRULock.

Referenced by _PG_init().

Variable Documentation

PG_MODULE_MAGIC

PG_MODULE_MAGIC

Definition at line 25 of file test_slru.c.

prev_shmem_request_hook

shmem_request_hook_type prev_shmem_request_hook = NULL

static

Definition at line 50 of file test_slru.c.

Referenced by _PG_init(), and test_slru_shmem_request().

prev_shmem_startup_hook

shmem_startup_hook_type prev_shmem_startup_hook = NULL

static

Definition at line 51 of file test_slru.c.

Referenced by _PG_init(), and test_slru_shmem_startup().

TestSlruCtlData

SlruCtlData TestSlruCtlData

static

Definition at line 47 of file test_slru.c.

TestSLRULock

LWLock TestSLRULock

Definition at line 44 of file test_slru.c.