Merge "Allow memory metrics on devices that use kernel LMK" am: 446014ecf9 (2dbd38d9) · Commits · e / os / android_system_core

lmkd/lmkd.c

+75 −2

Original line number	Original line	Diff line number	Diff line
	@@ -189,8 +189,8 @@ static struct sock_event_handler_info data_sock[MAX_DATA_CONN];
	/* vmpressure event handler data */		/* vmpressure event handler data */
	static struct event_handler_info vmpressure_hinfo[VMPRESS_LEVEL_COUNT];		static struct event_handler_info vmpressure_hinfo[VMPRESS_LEVEL_COUNT];

	/* 3 memory pressure levels, 1 ctrl listen socket, 2 ctrl data socket */		/* 3 memory pressure levels, 1 ctrl listen socket, 2 ctrl data socket, 1 lmk events */
	#define MAX_EPOLL_EVENTS (1 + MAX_DATA_CONN + VMPRESS_LEVEL_COUNT)		#define MAX_EPOLL_EVENTS (2 + MAX_DATA_CONN + VMPRESS_LEVEL_COUNT)
	static int epollfd;		static int epollfd;
	static int maxevents;		static int maxevents;

	@@ -1863,6 +1863,74 @@ err_open_mpfd:
	return false;		return false;
	}		}

			#ifdef LMKD_LOG_STATS
			static int kernel_poll_fd = -1;

			static void poll_kernel() {
			if (kernel_poll_fd == -1) {
			// not waiting
			return;
			}

			while (1) {
			char rd_buf[256];
			int bytes_read =
			TEMP_FAILURE_RETRY(pread(kernel_poll_fd, (void*)rd_buf, sizeof(rd_buf), 0));
			if (bytes_read <= 0) break;
			rd_buf[bytes_read] = '\0';

			int64_t pid;
			int64_t uid;
			int64_t group_leader_pid;
			int64_t min_flt;
			int64_t maj_flt;
			int64_t rss_in_pages;
			int16_t oom_score_adj;
			int16_t min_score_adj;
			int64_t starttime;
			char* taskname = 0;
			int fields_read = sscanf(rd_buf,
			"%" SCNd64 " %" SCNd64 " %" SCNd64 " %" SCNd64 " %" SCNd64
			" %" SCNd64 " %" SCNd16 " %" SCNd16 " %" SCNd64 "\n%m[^\n]",
			&pid, &uid, &group_leader_pid, &min_flt, &maj_flt, &rss_in_pages,
			&oom_score_adj, &min_score_adj, &starttime, &taskname);

			/* only the death of the group leader process is logged */
			if (fields_read == 10 && group_leader_pid == pid) {
			int64_t process_start_time_ns = starttime * (NS_PER_SEC / sysconf(_SC_CLK_TCK));
			stats_write_lmk_kill_occurred(log_ctx, LMK_KILL_OCCURRED, uid, taskname, oom_score_adj,
			min_flt, maj_flt, rss_in_pages * PAGE_SIZE, 0, 0,
			process_start_time_ns, min_score_adj);
			}

			free(taskname);
			}
			}

			static struct event_handler_info kernel_poll_hinfo = {0, poll_kernel};

			static void init_poll_kernel() {
			struct epoll_event epev;
			kernel_poll_fd =
			TEMP_FAILURE_RETRY(open("/proc/lowmemorykiller", O_RDONLY \| O_NONBLOCK \| O_CLOEXEC));

			if (kernel_poll_fd < 0) {
			ALOGE("kernel lmk event file could not be opened; errno=%d", kernel_poll_fd);
			return;
			}

			epev.events = EPOLLIN;
			epev.data.ptr = (void*)&kernel_poll_hinfo;
			if (epoll_ctl(epollfd, EPOLL_CTL_ADD, kernel_poll_fd, &epev) != 0) {
			ALOGE("epoll_ctl for lmk events failed; errno=%d", errno);
			close(kernel_poll_fd);
			kernel_poll_fd = -1;
			} else {
			maxevents++;
			}
			}
			#endif

	static int init(void) {		static int init(void) {
	struct epoll_event epev;		struct epoll_event epev;
	int i;		int i;
	@@ -1910,6 +1978,11 @@ static int init(void) {

	if (use_inkernel_interface) {		if (use_inkernel_interface) {
	ALOGI("Using in-kernel low memory killer interface");		ALOGI("Using in-kernel low memory killer interface");
			#ifdef LMKD_LOG_STATS
			if (enable_stats_log) {
			init_poll_kernel();
			}
			#endif
	} else {		} else {
	/* Try to use psi monitor first if kernel has it */		/* Try to use psi monitor first if kernel has it */
	use_psi_monitors = property_get_bool("ro.lmk.use_psi", true) &&		use_psi_monitors = property_get_bool("ro.lmk.use_psi", true) &&