Theo Schlossnagle wrote:
Hello all,
The probes can really give a different perspective on production
environments.
The patch has some nastiness to it that I'm sure people would want to
strategize on cleaning up. The main issue being that Apache is
constructed from a bunch of static apr/libtool built libraries. DTrace
doesn't work on archives. So, I've got some bloody knuckles from
bending the build system to keep things as normal ELF objects.
I had a first good step... and then a red herring issue that I worked
through with the DTrace team led me to a much less-elegant way of
building. I could revert to the original process (ld -r -o the objects
into library-esque packages) as DTrace can work on those.
The probes are neatly defined and placed, but the patches to the build
system are gruesome.
Uhm. yah. libtool-dep-extract, doesn't work with jlibtool.[1]
So, to get this to compile on OSX, I found out dtrace on OSX doesn't
have -G, and Apple says headers only/-h is enough. [2] Not having to
muck with the prelink steps makes this whole thing much easier to deal with.
For trunk, I had to mess around with http_request.c, as it seems the
2.2.x version is quite out of sync with trunk. (All due to the async
request processing work that happened in trunk).
The install-dtrace target is also slightly... worrying. For example:
@chown -R root:bin $(DESTDIR)/usr/lib
Seems like a bad thing for non-solaris operating systems, like OSX :-)
Attached is a patch for todays trunk, which seems to compile on OSX 10.5.
To get this in, I think we should make include/apache_probes.h a target
in the makefile, and not build it in configure.in. I'll try to get
something workong on OSX tomorrow and then hopefully someone can help me
with Solaris later,
The apr-util patch to the apr_hooks.h is simple and affords some nice
probability for future probe uses.
I've committed this patch to ARP-Util in r653681. [3]
I think we should add --enable-dtrace to APR{,-Util}'s configure.in, so
that we can wire up other things, and have a standard way of adding
things to the CPPFLAGS to enable it. (And to append those CPPFLAGS to
apr/apr-util's -config programs)
-Paul
[1] - http://svn.apache.org/repos/asf/apr/apr/trunk/build/jlibtool.c
[2] - http://archive.netbsd.se/?ml=dtrace-discuss&a=2007-10&m=5528648
[3] - https://svn.apache.org/viewvc?view=rev&revision=653681
Index: Makefile.in
===================================================================
--- Makefile.in (revision 653681)
+++ Makefile.in (working copy)
@@ -16,7 +16,7 @@
TARGETS = $(PROGRAMS) $(shared_build) $(other_targets)
INSTALL_TARGETS = install-conf install-htdocs install-error install-icons \
install-other install-cgi install-include install-suexec install-build \
- install-man
+ install-man install-dtrace
DISTCLEAN_TARGETS = include/ap_config_auto.h include/ap_config_layout.h \
modules.c config.cache config.log config.status build/config_vars.mk \
@@ -28,6 +28,12 @@
include $(top_builddir)/build/rules.mk
include $(top_srcdir)/build/program.mk
+install-dtrace:
+ @echo Installing DTrace library
+ @$(MKINSTALLDIRS) $(DESTDIR)/usr/lib/dtrace
+ @cp $(top_srcdir)/ap.d $(DESTDIR)/usr/lib/dtrace
+ @chmod 0644 $(DESTDIR)/usr/lib/dtrace/ap.d
+
install-conf:
@echo Installing configuration files
@$(MKINSTALLDIRS) $(DESTDIR)$(sysconfdir) $(DESTDIR)$(sysconfdir)/extra
Index: server/Makefile.in
===================================================================
--- server/Makefile.in (revision 653681)
+++ server/Makefile.in (working copy)
@@ -61,7 +61,7 @@
for dir in $(EXPORT_DIRS_APR); do \
(ls $$dir/ap[ru].h $$dir/ap[ru]_*.h >> $$tmp 2>/dev/null); \
done; \
- sort -u $$tmp > $@; \
+ sort -u $$tmp | grep -v apache_probes.h > $@; \
rm -f $$tmp
exports.c: export_files
Index: server/protocol.c
===================================================================
--- server/protocol.c (revision 653681)
+++ server/protocol.c (working copy)
@@ -842,9 +842,11 @@
apr_socket_t *csd;
apr_interval_time_t cur_timeout;
+
apr_pool_create(&p, conn->pool);
apr_pool_tag(p, "request");
r = apr_pcalloc(p, sizeof(request_rec));
+ AP_READ_REQUEST_ENTRY((intptr_t)r, (uintptr_t)conn);
r->pool = p;
r->connection = conn;
r->server = conn->base_server;
@@ -894,11 +896,12 @@
ap_update_child_status(conn->sbh, SERVER_BUSY_LOG, r);
ap_run_log_transaction(r);
apr_brigade_destroy(tmp_bb);
- return r;
+ goto traceout;
}
apr_brigade_destroy(tmp_bb);
- return NULL;
+ r = NULL;
+ goto traceout;
}
/* We may have been in keep_alive_timeout mode, so toggle back
@@ -921,7 +924,7 @@
ap_update_child_status(conn->sbh, SERVER_BUSY_LOG, r);
ap_run_log_transaction(r);
apr_brigade_destroy(tmp_bb);
- return r;
+ goto traceout;
}
if (apr_table_get(r->headers_in, "Transfer-Encoding")
@@ -949,7 +952,7 @@
ap_update_child_status(conn->sbh, SERVER_BUSY_LOG, r);
ap_run_log_transaction(r);
apr_brigade_destroy(tmp_bb);
- return r;
+ goto traceout;
}
}
@@ -1003,14 +1006,15 @@
ap_send_error_response(r, 0);
ap_update_child_status(conn->sbh, SERVER_BUSY_LOG, r);
ap_run_log_transaction(r);
- return r;
+ goto traceout;
}
if ((access_status = ap_run_post_read_request(r))) {
ap_die(access_status, r);
ap_update_child_status(conn->sbh, SERVER_BUSY_LOG, r);
ap_run_log_transaction(r);
- return NULL;
+ r = NULL;
+ goto traceout;
}
if (((expect = apr_table_get(r->headers_in, "Expect")) != NULL)
@@ -1032,11 +1036,16 @@
ap_send_error_response(r, 0);
ap_update_child_status(conn->sbh, SERVER_BUSY_LOG, r);
ap_run_log_transaction(r);
- return r;
+ goto traceout;
}
}
+ AP_READ_REQUEST_SUCCESS((uintptr_t)r, (char *)r->method, (char *)r->uri,
+ (char *)r->server->defn_name, r->status);
return r;
+ traceout:
+ AP_READ_REQUEST_FAILURE((uintptr_t)r);
+ return r;
}
/* if a request with a body creates a subrequest, clone the original request's
Index: modules/http/http_request.c
===================================================================
--- modules/http/http_request.c (revision 653681)
+++ modules/http/http_request.c (working copy)
@@ -234,6 +234,7 @@
* Use this hook with extreme care and only if you know what you are
* doing.
*/
+ AP_PROCESS_REQUEST_ENTRY((uintptr_t)r, r->uri);
if (ap_extended_status)
ap_time_process_request(r->connection->sbh, START_PREQUEST);
access_status = ap_run_quick_handler(r, 0); /* Not a look-up request */
@@ -273,8 +274,11 @@
c->cs->state = CONN_STATE_WRITE_COMPLETION;
check_pipeline(c);
- if (ap_extended_status)
+ if (ap_extended_status) {
ap_time_process_request(c->sbh, STOP_PREQUEST);
+ }
+
+ AP_PROCESS_REQUEST_RETURN((uintptr_t)r, r->uri, access_status);
}
void ap_process_request(request_rec *r)
@@ -305,11 +309,13 @@
" client", r->unparsed_uri);
}
}
+
if (ap_extended_status) {
ap_time_process_request(c->sbh, STOP_PREQUEST);
}
}
+
static apr_table_t *rename_original_env(apr_pool_t *p, apr_table_t *t)
{
const apr_array_header_t *env_arr = apr_table_elts(t);
@@ -489,6 +495,8 @@
request_rec *new = internal_internal_redirect(new_uri, r);
int access_status;
+ AP_INTERNAL_REDIRECT(r->uri, new_uri);
+
/* ap_die was already called, if an error occured */
if (!new) {
return;
Index: modules/proxy/mod_proxy.c
===================================================================
--- modules/proxy/mod_proxy.c (revision 653681)
+++ modules/proxy/mod_proxy.c (working copy)
@@ -979,6 +979,7 @@
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
"Running scheme %s handler (attempt %d)",
scheme, attempts);
+ AP_PROXY_RUN(r);
access_status = proxy_run_scheme_handler(r, worker, conf,
url, NULL, 0);
if (access_status == OK)
@@ -1026,6 +1027,7 @@
ap_proxy_post_request(worker, balancer, r, conf);
proxy_run_request_status(&access_status, r);
+ AP_PROXY_RUN_FINISHED(r, attempts, access_status);
return access_status;
}
Index: modules/mappers/mod_rewrite.c
===================================================================
--- modules/mappers/mod_rewrite.c (revision 653681)
+++ modules/mappers/mod_rewrite.c (working copy)
@@ -486,7 +486,8 @@
conf = ap_get_module_config(r->server->module_config, &rewrite_module);
- if (!conf->rewritelogfp || level > conf->rewriteloglevel) {
+ if ((!conf->rewritelogfp || level > conf->rewriteloglevel) &&
+ !AP_REWRITE_LOG_ENABLED()) {
return;
}
@@ -520,6 +521,11 @@
perdir ? "] ": "",
text);
+ AP_REWRITE_LOG((uintptr_t)r, level, r->main ? 0 : 1, (char
*)ap_get_server_name(r), logline);
+
+ if (!conf->rewritelogfp || level > conf->rewriteloglevel)
+ return;
+
rv = apr_global_mutex_lock(rewrite_log_lock);
if (rv != APR_SUCCESS) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r,
Index: apache_probes.d
===================================================================
--- apache_probes.d (revision 0)
+++ apache_probes.d (revision 0)
@@ -0,0 +1,172 @@
+provider ap {
+ /* Explicit, core */
+ probe internal__redirect(char *, char *);
+ probe process__request__entry(unsigned long, char *);
+ probe process__request__return(unsigned long, char *, unsigned int);
+ probe read__request__entry(unsigned long, unsigned long);
+ probe read__request__success(unsigned long, char *, char *, char *, unsigned
int);
+ probe read__request__failure(unsigned long);
+
+ /* Explicit, modules */
+ probe rewrite__log(unsigned long, int, int, char *, char *);
+ probe proxy__run(unsigned long);
+ probe proxy__run__finished(unsigned long, unsigned int, unsigned int);
+
+ /* Implicit, APR hooks */
+ probe translate_name__entry();
+ probe translate_name__dispatch__invoke(char *);
+ probe translate_name__dispatch__complete(char *, unsigned int);
+ probe translate_name__return(unsigned int);
+ probe map_to_storage__entry();
+ probe map_to_storage__dispatch__invoke(char *);
+ probe map_to_storage__dispatch__complete(char *, unsigned int);
+ probe map_to_storage__return(unsigned int);
+ probe check_user_id__entry();
+ probe check_user_id__dispatch__invoke(char *);
+ probe check_user_id__dispatch__complete(char *, unsigned int);
+ probe check_user_id__return(unsigned int);
+ probe fixups__entry();
+ probe fixups__dispatch__invoke(char *);
+ probe fixups__dispatch__complete(char *, unsigned int);
+ probe fixups__return(unsigned int);
+ probe type_checker__entry();
+ probe type_checker__dispatch__invoke(char *);
+ probe type_checker__dispatch__complete(char *, unsigned int);
+ probe type_checker__return(unsigned int);
+ probe access_checker__entry();
+ probe access_checker__dispatch__invoke(char *);
+ probe access_checker__dispatch__complete(char *, unsigned int);
+ probe access_checker__return(unsigned int);
+ probe auth_checker__entry();
+ probe auth_checker__dispatch__invoke(char *);
+ probe auth_checker__dispatch__complete(char *, unsigned int);
+ probe auth_checker__return(unsigned int);
+ probe insert_filter__entry();
+ probe insert_filter__dispatch__invoke(char *);
+ probe insert_filter__dispatch__complete(char *, unsigned int);
+ probe insert_filter__return(unsigned int);
+ probe create_connection__entry();
+ probe create_connection__dispatch__invoke(char *);
+ probe create_connection__dispatch__complete(char *, unsigned int);
+ probe create_connection__return(unsigned int);
+ probe pre_connection__entry();
+ probe pre_connection__dispatch__invoke(char *);
+ probe pre_connection__dispatch__complete(char *, unsigned int);
+ probe pre_connection__return(unsigned int);
+ probe process_connection__entry();
+ probe process_connection__dispatch__invoke(char *);
+ probe process_connection__dispatch__complete(char *, unsigned int);
+ probe process_connection__return(unsigned int);
+ probe create_request__entry();
+ probe create_request__dispatch__invoke(char *);
+ probe create_request__dispatch__complete(char *, unsigned int);
+ probe create_request__return(unsigned int);
+ probe header_parser__entry();
+ probe header_parser__dispatch__invoke(char *);
+ probe header_parser__dispatch__complete(char *, unsigned int);
+ probe header_parser__return(unsigned int);
+ probe pre_config__entry();
+ probe pre_config__dispatch__invoke(char *);
+ probe pre_config__dispatch__complete(char *, unsigned int);
+ probe pre_config__return(unsigned int);
+ probe test_config__entry();
+ probe test_config__dispatch__invoke(char *);
+ probe test_config__dispatch__complete(char *, unsigned int);
+ probe test_config__return(unsigned int);
+ probe post_config__entry();
+ probe post_config__dispatch__invoke(char *);
+ probe post_config__dispatch__complete(char *, unsigned int);
+ probe post_config__return(unsigned int);
+ probe open_logs__entry();
+ probe open_logs__dispatch__invoke(char *);
+ probe open_logs__dispatch__complete(char *, unsigned int);
+ probe open_logs__return(unsigned int);
+ probe child_init__entry();
+ probe child_init__dispatch__invoke(char *);
+ probe child_init__dispatch__complete(char *, unsigned int);
+ probe child_init__return(unsigned int);
+ probe handler__entry();
+ probe handler__dispatch__invoke(char *);
+ probe handler__dispatch__complete(char *, unsigned int);
+ probe handler__return(unsigned int);
+ probe quick_handler__entry();
+ probe quick_handler__dispatch__invoke(char *);
+ probe quick_handler__dispatch__complete(char *, unsigned int);
+ probe quick_handler__return(unsigned int);
+ probe optional_fn_retrieve__entry();
+ probe optional_fn_retrieve__dispatch__invoke(char *);
+ probe optional_fn_retrieve__dispatch__complete(char *, unsigned int);
+ probe optional_fn_retrieve__return(unsigned int);
+ probe get_mgmt_items__entry();
+ probe get_mgmt_items__dispatch__invoke(char *);
+ probe get_mgmt_items__dispatch__complete(char *, unsigned int);
+ probe get_mgmt_items__return(unsigned int);
+ probe pre_mpm__entry();
+ probe pre_mpm__dispatch__invoke(char *);
+ probe pre_mpm__dispatch__complete(char *, unsigned int);
+ probe pre_mpm__return(unsigned int);
+ probe default_port__entry();
+ probe default_port__dispatch__invoke(char *);
+ probe default_port__dispatch__complete(char *, unsigned int);
+ probe default_port__return(unsigned int);
+ probe http_scheme__entry();
+ probe http_scheme__dispatch__invoke(char *);
+ probe http_scheme__dispatch__complete(char *, unsigned int);
+ probe http_scheme__return(unsigned int);
+ probe error_log__entry();
+ probe error_log__dispatch__invoke(char *);
+ probe error_log__dispatch__complete(char *, unsigned int);
+ probe error_log__return(unsigned int);
+ probe log_transaction__entry();
+ probe log_transaction__dispatch__invoke(char *);
+ probe log_transaction__dispatch__complete(char *, unsigned int);
+ probe log_transaction__return(unsigned int);
+ probe monitor__entry();
+ probe monitor__dispatch__invoke(char *);
+ probe monitor__dispatch__complete(char *, unsigned int);
+ probe monitor__return(unsigned int);
+ probe post_read_request__entry();
+ probe post_read_request__dispatch__invoke(char *);
+ probe post_read_request__dispatch__complete(char *, unsigned int);
+ probe post_read_request__return(unsigned int);
+ probe get_suexec_identity__entry();
+ probe get_suexec_identity__dispatch__invoke(char *);
+ probe get_suexec_identity__dispatch__complete(char *, unsigned int);
+ probe get_suexec_identity__return(unsigned int);
+ probe insert_error_filter__entry();
+ probe insert_error_filter__dispatch__invoke(char *);
+ probe insert_error_filter__dispatch__complete(char *, unsigned int);
+ probe insert_error_filter__return(unsigned int);
+
+ /* Implicit, APR hooks for proxy */
+ probe scheme_handler__entry();
+ probe scheme_handler__dispatch__invoke(char *);
+ probe scheme_handler__dispatch__complete(char *, unsigned int);
+ probe scheme_handler__return(unsigned int);
+ probe canon_handler__entry();
+ probe canon_handler__dispatch__invoke(char *);
+ probe canon_handler__dispatch__complete(char *, unsigned int);
+ probe canon_handler__return(unsigned int);
+ probe pre_request__entry();
+ probe pre_request__dispatch__invoke(char *);
+ probe pre_request__dispatch__complete(char *, unsigned int);
+ probe pre_request__return(unsigned int);
+ probe post_request__entry();
+ probe post_request__dispatch__invoke(char *);
+ probe post_request__dispatch__complete(char *, unsigned int);
+ probe post_request__return(unsigned int);
+
+ /* Implicit, APR hooks for dav */
+ probe gather_propsets__entry();
+ probe gather_propsets__dispatch__invoke(char *);
+ probe gather_propsets__dispatch__complete(char *, unsigned int);
+ probe gather_propsets__return(unsigned int);
+ probe find_liveprop__entry();
+ probe find_liveprop__dispatch__invoke(char *);
+ probe find_liveprop__dispatch__complete(char *, unsigned int);
+ probe find_liveprop__return(unsigned int);
+ probe insert_all_liveprops__entry();
+ probe insert_all_liveprops__dispatch__invoke(char *);
+ probe insert_all_liveprops__dispatch__complete(char *, unsigned int);
+ probe insert_all_liveprops__return(unsigned int);
+};
Index: include/ap_config.h
===================================================================
--- include/ap_config.h (revision 653681)
+++ include/ap_config.h (working copy)
@@ -238,6 +238,13 @@
#define AP_NONBLOCK_WHEN_MULTI_LISTEN 1
#endif
+#if AP_ENABLE_DTRACE && HAVE_SYS_SDT_H
+#include <sys/sdt.h>
+#else
+#undef _DTRACE_VERSION
+#endif
+#include "apache_probes.h"
+
/* TODO - We need to put OS detection back to make all the following work */
#if defined(SUNOS4) || defined(IRIX) || defined(NEXT) || defined(AUX3) \
Index: configure.in
===================================================================
--- configure.in (revision 653681)
+++ configure.in (working copy)
@@ -381,7 +381,8 @@
strings.h \
sys/prctl.h \
sys/processor.h \
-sys/sem.h
+sys/sem.h \
+sys/sdt.h
)
AC_HEADER_SYS_WAIT
@@ -447,6 +448,25 @@
[if test "$withval" = "yes"; then AC_MSG_ERROR('option --with-sslport
requires a value (the SSL TCP port number)'); else SSLPORT="$withval"; fi],
[SSLPORT=443])
+AC_ARG_ENABLE(dtrace,APACHE_HELP_STRING(--enable-dtrace,Enable DTrace probes),
+[
+ enable_dtrace=$enableval
+ APR_ADDTO(CPPFLAGS, -DAPR_DTRACE_PROVIDER)
+],
+[
+ enable_dtrace=no
+])
+
+DTRACE=true
+if test $enable_dtrace = "yes" -a "$ac_cv_header_sys_sdt_h" = "yes"; then
+ AC_DEFINE(AP_ENABLE_DTRACE, 1,
+ [Enable DTrace probes])
+ DTRACE="/usr/sbin/dtrace $DTRACEFLAGS"
+ test -f include/apache_probes.h || $DTRACE -h -s apache_probes.d -o
include/apache_probes.h
+fi
+
+APACHE_SUBST(DTRACE)
+
APR_CHECK_APR_DEFINE(APR_HAVE_IPV6)
AC_ARG_ENABLE(v4-mapped,APACHE_HELP_STRING(--enable-v4-mapped,Allow IPv6
sockets to handle IPv4 connections),
@@ -504,6 +524,9 @@
AC_SUBST(PILDFLAGS)
prefix="$orig_prefix"
+cat >static_modules.mk<<EOF
+MODULE_OBJS = \\
+EOF
APACHE_ENABLE_MODULES
dnl reading config stubs
@@ -687,6 +710,7 @@
HTTPD_VERSION=`$abs_srcdir/build/get-version.sh all
$abs_srcdir/include/ap_release.h AP_SERVER`
AC_SUBST(HTTPD_VERSION)
+echo >>static_modules.mk
AC_OUTPUT($APACHE_OUTPUT_FILES docs/conf/httpd.conf
docs/conf/extra/httpd-autoindex.conf docs/conf/extra/httpd-dav.conf
docs/conf/extra/httpd-default.conf docs/conf/extra/httpd-info.conf
docs/conf/extra/httpd-languages.conf docs/conf/extra/httpd-manual.conf
docs/conf/extra/httpd-mpm.conf docs/conf/extra/httpd-multilang-errordoc.conf
docs/conf/extra/httpd-ssl.conf docs/conf/extra/httpd-userdir.conf
docs/conf/extra/httpd-vhosts.conf include/ap_config_layout.h support/apxs
support/apachectl support/dbmmanage support/envvars-std
support/log_server_status support/logresolve.pl support/phf_abuse_log.cgi
support/split-logfile build/rules.mk build/pkg/pkginfo
build/config_vars.sh,[true],[
APACHE_GEN_MAKEFILES
])
