Implement perf stat --control for cgi

Zend/zend_perf_stat.h

@@ -0,0 +1,135 @@
+/*
+   +----------------------------------------------------------------------+
+   | Zend Engine                                                          |
+   +----------------------------------------------------------------------+
+   | Copyright © Zend Technologies Ltd., a subsidiary company of          |
+   |     Perforce Software, Inc., and Contributors.                       |
+   +----------------------------------------------------------------------+
+   | This source file is subject to the Modified BSD License that is      |
+   | bundled with this package in the file LICENSE, and is available      |
+   | through the World Wide Web at <https://www.php.net/license/>.        |
+   |                                                                      |
+   | SPDX-License-Identifier: BSD-3-Clause                                |
+   +----------------------------------------------------------------------+
+   | Authors: Ilija Tovilo <ilutov@php.net>                               |
+   +----------------------------------------------------------------------+
+*/
+
+#ifndef ZEND_PERF_STAT_H
+#define ZEND_PERF_STAT_H
+
+#include "zend_portability.h"
+
+# if !(HAVE_FCNTL_H && HAVE_SYS_SELECT_H && HAVE_SYS_STAT_H && HAVE_SYS_TIME_H && HAVE_UNISTD_H)
+static void zend_perf_stat_enable(void) {}
+static void zend_perf_stat_disable(void) {}
+# else
+
+# include <fcntl.h>
+# include <sys/select.h>
+# include <sys/stat.h>
+# include <unistd.h>
+
+# include "Zend/zend.h"
+
+# define ZPS_CTL_FIFO_ENV "PERF_STAT_CTL_FIFO"
+# define ZPS_ACK_FIFO_ENV "PERF_STAT_ACK_FIFO"
+
+static int ctl_fd = -2;
+static int ack_fd = -2;
+
+static int zps_open_fifo(const char *env_name, int flags)
+{
+	const char *path = getenv(env_name);
+
+	if (path == NULL || path[0] == '\0') {
+		return -1;
+	}
+
+# ifdef O_CLOEXEC
+	flags |= O_CLOEXEC;
+# endif
+	int fd = open(path, flags | O_NONBLOCK);
+	if (fd < 0) {
+		fprintf(stderr, "Failed to open fifo %s\n", path);
+		fflush(stderr);
+		zend_bailout();
+	}
+
+	struct stat st;
+	if (fstat(fd, &st) != 0 || !S_ISFIFO(st.st_mode)) {
+		close(fd);
+		fprintf(stderr, "File %s is not a fifo\n", path);
+		fflush(stderr);
+		zend_bailout();
+	}
+	return fd;
+}
+
+static void zps_init(void)
+{
+	if (ctl_fd == -2) {
+		ctl_fd = zps_open_fifo(ZPS_CTL_FIFO_ENV, O_WRONLY);
+	}
+	if (ack_fd == -2) {
+		ack_fd = zps_open_fifo(ZPS_ACK_FIFO_ENV, O_RDONLY);
+	}
+}
+
+static void zps_wait_ack(void)
+{
+	if (ack_fd < 0) {
+		return;
+	}
+
+	struct timeval timeout;
+	timeout.tv_sec = 1;
+	timeout.tv_usec = 0;
+
+	fd_set readfds;
+	FD_ZERO(&readfds);
+	FD_SET(ack_fd, &readfds);
+	if (select(ack_fd + 1, &readfds, NULL, NULL, &timeout) <= 0) {
+		return;
+	}
+
+	char ack[sizeof("ack\n") - 1];
+	ssize_t bytes_read;
+	do {
+		bytes_read = read(ack_fd, ack, sizeof(ack));
+	} while (bytes_read > 0);
+}
+
+static void zps_control(const char *command, size_t command_len)
+{
+	zps_init();
+
+	if (ctl_fd < 0) {
+		return;
+	}
+
+	if (write(ctl_fd, command, command_len) != (ssize_t) command_len) {
+		close(ctl_fd);
+		ctl_fd = -1;
+		return;
+	}
+
+	zps_wait_ack();
+}
+
+static void zend_perf_stat_enable(void)
+{
+	static const char command[] = "enable\n";
+
+	zps_control(command, sizeof(command) - 1);
+}
+
+static void zend_perf_stat_disable(void)
+{
+	static const char command[] = "disable\n";
+
+	zps_control(command, sizeof(command) - 1);
+}
+
+# endif
+#endif

sapi/cgi/cgi_main.c

@@ -95,6 +95,8 @@ int __riscosify_control = __RISCOSIFY_STRICT_UNIX_SPECS;
 # endif
 #endif
 
+#include "zend_perf_stat.h"
+
 #ifndef PHP_WIN32
 /* XXX this will need to change later when threaded fastcgi is implemented.  shane */
 static struct sigaction act, old_term, old_quit, old_int;
@@ -1733,6 +1735,7 @@ int main(int argc, char *argv[])
 	int warmup_repeats = 0;
 	int repeats = 1;
 	int benchmark = 0;
+	bool perf_enabled = false;
 #ifdef HAVE_GETTIMEOFDAY
 	struct timeval start, end;
 #else
@@ -2441,14 +2444,16 @@ consult the installation file that came with this distribution, or visit \n\
 				}
 			} /* end !cgi && !fastcgi */
 
-#ifdef HAVE_VALGRIND
 			if (warmup_repeats == 0) {
+				zend_perf_stat_enable();
+				perf_enabled = true;
+#ifdef HAVE_VALGRIND
 				CALLGRIND_START_INSTRUMENTATION;
 # ifdef HAVE_VALGRIND_CACHEGRIND_H
 				CACHEGRIND_START_INSTRUMENTATION;
 # endif
-			}
 #endif
+			}
 
 			/* request startup only after we've done all we can to
 			 * get path_translated */
@@ -2568,6 +2573,10 @@ consult the installation file that came with this distribution, or visit \n\
 				SG(request_info).query_string = NULL;
 			}
 
+			if (perf_enabled) {
+				zend_perf_stat_disable();
+				perf_enabled = false;
+			}
 #ifdef HAVE_VALGRIND
 			/* We're not interested in measuring shutdown */
 			CALLGRIND_STOP_INSTRUMENTATION;