#include "postgres.h"
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include "fmgr.h"
#include "jit/jit.h"
#include "miscadmin.h"
#include "nodes/execnodes.h"
#include "portability/instr_time.h"
#include "utils/fmgrprotos.h"

Include dependency graph for jit.c:

Functions
static bool	provider_init (void)

Datum	pg_jit_available (PG_FUNCTION_ARGS)

void	jit_reset_after_error (void)

void	jit_release_context (JitContext *context)

bool	jit_compile_expr (struct ExprState *state)

void	InstrJitAgg (JitInstrumentation dst, JitInstrumentation add)

Variables
bool	jit_enabled = true

char *	jit_provider = NULL

bool	jit_debugging_support = false

bool	jit_dump_bitcode = false

bool	jit_expressions = true

bool	jit_profiling_support = false

bool	jit_tuple_deforming = true

double	jit_above_cost = 100000

double	jit_inline_above_cost = 500000

double	jit_optimize_above_cost = 500000

static JitProviderCallbacks	provider

static bool	provider_successfully_loaded = false

static bool	provider_failed_loading = false

Function Documentation

◆ InstrJitAgg()

void InstrJitAgg	(	JitInstrumentation *	dst,
		JitInstrumentation *	add
	)

Definition at line 182 of file jit.c.

{
    dst->created_functions += add->created_functions;
    INSTR_TIME_ADD(dst->generation_counter, add->generation_counter);
    INSTR_TIME_ADD(dst->deform_counter, add->deform_counter);
    INSTR_TIME_ADD(dst->inlining_counter, add->inlining_counter);
    INSTR_TIME_ADD(dst->optimization_counter, add->optimization_counter);
    INSTR_TIME_ADD(dst->emission_counter, add->emission_counter);
}

References JitInstrumentation::created_functions, JitInstrumentation::deform_counter, JitInstrumentation::emission_counter, JitInstrumentation::generation_counter, JitInstrumentation::inlining_counter, INSTR_TIME_ADD, and JitInstrumentation::optimization_counter.

Referenced by ExecParallelRetrieveJitInstrumentation(), and ExplainPrintJITSummary().

◆ jit_compile_expr()

bool jit_compile_expr ( struct ExprState * state )

Definition at line 151 of file jit.c.

{
    /*
     * We can easily create a one-off context for functions without an
     * associated PlanState (and thus EState). But because there's no executor
     * shutdown callback that could deallocate the created function, they'd
     * live to the end of the transactions, where they'd be cleaned up by the
     * resowner machinery. That can lead to a noticeable amount of memory
     * usage, and worse, trigger some quadratic behaviour in gdb. Therefore,
     * at least for now, don't create a JITed function in those circumstances.
     */
    if (!state->parent)
        return false;
 
    /* if no jitting should be performed at all */
    if (!(state->parent->state->es_jit_flags & PGJIT_PERFORM))
        return false;
 
    /* or if expressions aren't JITed */
    if (!(state->parent->state->es_jit_flags & PGJIT_EXPR))
        return false;
 
    /* this also takes !jit_enabled into account */
    if (provider_init())
        return provider.compile_expr(state);
 
    return false;
}

References JitProviderCallbacks::compile_expr, PGJIT_EXPR, PGJIT_PERFORM, provider, and provider_init().

Referenced by ExecReadyExpr().

◆ jit_release_context()

void jit_release_context ( JitContext * context )

Definition at line 137 of file jit.c.

{
    if (provider_successfully_loaded)
        provider.release_context(context);
 
    pfree(context);
}

References pfree(), provider, provider_successfully_loaded, and JitProviderCallbacks::release_context.

Referenced by FreeExecutorState(), and ResOwnerReleaseJitContext().

◆ jit_reset_after_error()

void jit_reset_after_error ( void )

Definition at line 127 of file jit.c.

{
    if (provider_successfully_loaded)
        provider.reset_after_error();
}

References provider, provider_successfully_loaded, and JitProviderCallbacks::reset_after_error.

Referenced by PostgresMain().

◆ pg_jit_available()

Datum pg_jit_available ( PG_FUNCTION_ARGS )

Definition at line 56 of file jit.c.

{
    PG_RETURN_BOOL(provider_init());
}

References PG_RETURN_BOOL, and provider_init().

◆ provider_init()

static bool provider_init ( void )

static

Definition at line 67 of file jit.c.

{
    char        path[MAXPGPATH];
    JitProviderInit init;
 
    /* don't even try to load if not enabled */
    if (!jit_enabled)
        return false;
 
    /*
     * Don't retry loading after failing - attempting to load JIT provider
     * isn't cheap.
     */
    if (provider_failed_loading)
        return false;
    if (provider_successfully_loaded)
        return true;
 
    /*
     * Check whether shared library exists. We do that check before actually
     * attempting to load the shared library (via load_external_function()),
     * because that'd error out in case the shlib isn't available.
     */
    snprintf(path, MAXPGPATH, "%s/%s%s", pkglib_path, jit_provider, DLSUFFIX);
    elog(DEBUG1, "probing availability of JIT provider at %s", path);
    if (!pg_file_exists(path))
    {
        elog(DEBUG1,
             "provider not available, disabling JIT for current session");
        provider_failed_loading = true;
        return false;
    }
 
    /*
     * If loading functions fails, signal failure. We do so because
     * load_external_function() might error out despite the above check if
     * e.g. the library's dependencies aren't installed. We want to signal
     * ERROR in that case, so the user is notified, but we don't want to
     * continually retry.
     */
    provider_failed_loading = true;
 
    /* and initialize */
    init = (JitProviderInit)
        load_external_function(path, "_PG_jit_provider_init", true, NULL);
    init(&provider);
 
    provider_successfully_loaded = true;
    provider_failed_loading = false;
 
    elog(DEBUG1, "successfully loaded JIT provider in current session");
 
    return true;
}