From fbc394252588325b6e7ecd1ab65ad40b51763c58 Mon Sep 17 00:00:00 2001
From: Lennart Poettering <lennart@poettering.net>
Date: Tue, 7 Aug 2018 12:08:24 +0200
Subject: [PATCH] logind: add hashtable for finding session by leader PID
This is useful later on, when we quickly want to find the session for a
leader PID.
(cherry picked from commit 238794b15082e6f61d0ce2943d39205289fff7f0)
Related: #2122288
---
src/login/logind-core.c | 15 ++++++++------
src/login/logind-dbus.c | 3 +--
src/login/logind-session.c | 41 +++++++++++++++++++++++++++++++++++---
src/login/logind-session.h | 1 +
src/login/logind.c | 4 +++-
src/login/logind.h | 1 +
6 files changed, 53 insertions(+), 12 deletions(-)
diff --git a/src/login/logind-core.c b/src/login/logind-core.c
index 7e33f8e6aa..a1943b6f9d 100644
--- a/src/login/logind-core.c
+++ b/src/login/logind-core.c
@@ -339,13 +339,16 @@ int manager_get_session_by_pid(Manager *m, pid_t pid, Session **ret) {
if (!pid_is_valid(pid))
return -EINVAL;
- r = cg_pid_get_unit(pid, &unit);
- if (r < 0)
- goto not_found;
+ s = hashmap_get(m->sessions_by_leader, PID_TO_PTR(pid));
+ if (!s) {
+ r = cg_pid_get_unit(pid, &unit);
+ if (r < 0)
+ goto not_found;
- s = hashmap_get(m->session_units, unit);
- if (!s)
- goto not_found;
+ s = hashmap_get(m->session_units, unit);
+ if (!s)
+ goto not_found;
+ }
if (ret)
*ret = s;
diff --git a/src/login/logind-dbus.c b/src/login/logind-dbus.c
index 0248042308..01bfef4ff7 100644
--- a/src/login/logind-dbus.c
+++ b/src/login/logind-dbus.c
@@ -784,9 +784,8 @@ static int method_create_session(sd_bus_message *message, void *userdata, sd_bus
goto fail;
session_set_user(session, user);
+ session_set_leader(session, leader);
- session->leader = leader;
- session->audit_id = audit_id;
session->type = t;
session->class = c;
session->remote = remote;
diff --git a/src/login/logind-session.c b/src/login/logind-session.c
index d666f86d3f..cc838ca383 100644
--- a/src/login/logind-session.c
+++ b/src/login/logind-session.c
@@ -121,6 +121,9 @@ Session* session_free(Session *s) {
free(s->scope);
}
+ if (pid_is_valid(s->leader))
+ (void) hashmap_remove_value(s->manager->sessions_by_leader, PID_TO_PTR(s->leader), s);
+
free(s->scope_job);
sd_bus_message_unref(s->create_message);
@@ -149,6 +152,30 @@ void session_set_user(Session *s, User *u) {
user_update_last_session_timer(u);
}
+int session_set_leader(Session *s, pid_t pid) {
+ int r;
+
+ assert(s);
+
+ if (!pid_is_valid(pid))
+ return -EINVAL;
+
+ if (s->leader == pid)
+ return 0;
+
+ r = hashmap_put(s->manager->sessions_by_leader, PID_TO_PTR(pid), s);
+ if (r < 0)
+ return r;
+
+ if (pid_is_valid(s->leader))
+ (void) hashmap_remove_value(s->manager->sessions_by_leader, PID_TO_PTR(s->leader), s);
+
+ s->leader = pid;
+ (void) audit_session_from_pid(pid, &s->audit_id);
+
+ return 1;
+}
+
static void session_save_devices(Session *s, FILE *f) {
SessionDevice *sd;
Iterator i;
@@ -473,8 +500,16 @@ int session_load(Session *s) {
}
if (leader) {
- if (parse_pid(leader, &s->leader) >= 0)
- (void) audit_session_from_pid(s->leader, &s->audit_id);
+ pid_t pid;
+
+ r = parse_pid(leader, &pid);
+ if (r < 0)
+ log_debug_errno(r, "Failed to parse leader PID of session: %s", leader);
+ else {
+ r = session_set_leader(s, pid);
+ if (r < 0)
+ log_warning_errno(r, "Failed to set session leader PID, ignoring: %m");
+ }
}
if (type) {
@@ -910,7 +945,7 @@ int session_get_idle_hint(Session *s, dual_timestamp *t) {
/* For sessions with a leader but no explicitly configured
* tty, let's check the controlling tty of the leader */
- if (s->leader > 0) {
+ if (pid_is_valid(s->leader)) {
r = get_process_ctty_atime(s->leader, &atime);
if (r >= 0)
goto found_atime;
diff --git a/src/login/logind-session.h b/src/login/logind-session.h
index 7da845cea3..8c7d0301f2 100644
--- a/src/login/logind-session.h
+++ b/src/login/logind-session.h
@@ -124,6 +124,7 @@ Session* session_free(Session *s);
DEFINE_TRIVIAL_CLEANUP_FUNC(Session *, session_free);
void session_set_user(Session *s, User *u);
+int session_set_leader(Session *s, pid_t pid);
bool session_may_gc(Session *s, bool drop_not_started);
void session_add_to_gc_queue(Session *s);
int session_activate(Session *s);
diff --git a/src/login/logind.c b/src/login/logind.c
index 25de9a6ab2..6b576dad0d 100644
--- a/src/login/logind.c
+++ b/src/login/logind.c
@@ -46,6 +46,7 @@ static int manager_new(Manager **ret) {
m->devices = hashmap_new(&string_hash_ops);
m->seats = hashmap_new(&string_hash_ops);
m->sessions = hashmap_new(&string_hash_ops);
+ m->sessions_by_leader = hashmap_new(NULL);
m->users = hashmap_new(NULL);
m->inhibitors = hashmap_new(&string_hash_ops);
m->buttons = hashmap_new(&string_hash_ops);
@@ -53,7 +54,7 @@ static int manager_new(Manager **ret) {
m->user_units = hashmap_new(&string_hash_ops);
m->session_units = hashmap_new(&string_hash_ops);
- if (!m->devices || !m->seats || !m->sessions || !m->users || !m->inhibitors || !m->buttons || !m->user_units || !m->session_units)
+ if (!m->devices || !m->seats || !m->sessions || !m->sessions_by_leader || !m->users || !m->inhibitors || !m->buttons || !m->user_units || !m->session_units)
return -ENOMEM;
m->udev = udev_new();
@@ -112,6 +113,7 @@ static Manager* manager_unref(Manager *m) {
hashmap_free(m->devices);
hashmap_free(m->seats);
hashmap_free(m->sessions);
+ hashmap_free(m->sessions_by_leader);
hashmap_free(m->users);
hashmap_free(m->inhibitors);
hashmap_free(m->buttons);
diff --git a/src/login/logind.h b/src/login/logind.h
index bb127bf4a5..7f94dea2f6 100644
--- a/src/login/logind.h
+++ b/src/login/logind.h
@@ -26,6 +26,7 @@ struct Manager {
Hashmap *devices;
Hashmap *seats;
Hashmap *sessions;
+ Hashmap *sessions_by_leader;
Hashmap *users;
Hashmap *inhibitors;
Hashmap *buttons;