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author | Linus Torvalds <torvalds@linux-foundation.org> | 2022-05-27 02:57:20 +0300 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2022-05-27 02:57:20 +0300 |
commit | 44d35720c9a660074b77ab9de37abf2c01c5b44f (patch) | |
tree | 8e1242c7ff2e3559bff80ab681ccbe9bb2c4bffb /kernel/trace | |
parent | cdeffe87f790dfd1baa193020411ce9a538446d7 (diff) | |
parent | 494dcdf46e5cdee926c9f441d37e3ea1db57d1da (diff) | |
download | linux-44d35720c9a660074b77ab9de37abf2c01c5b44f.tar.xz |
Merge tag 'sysctl-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux
Pull sysctl updates from Luis Chamberlain:
"For two kernel releases now kernel/sysctl.c has been being cleaned up
slowly, since the tables were grossly long, sprinkled with tons of
#ifdefs and all this caused merge conflicts with one susbystem or
another.
This tree was put together to help try to avoid conflicts with these
cleanups going on different trees at time. So nothing exciting on this
pull request, just cleanups.
Thanks a lot to the Uniontech and Huawei folks for doing some of this
nasty work"
* tag 'sysctl-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux: (28 commits)
sched: Fix build warning without CONFIG_SYSCTL
reboot: Fix build warning without CONFIG_SYSCTL
kernel/kexec_core: move kexec_core sysctls into its own file
sysctl: minor cleanup in new_dir()
ftrace: fix building with SYSCTL=y but DYNAMIC_FTRACE=n
fs/proc: Introduce list_for_each_table_entry for proc sysctl
mm: fix unused variable kernel warning when SYSCTL=n
latencytop: move sysctl to its own file
ftrace: fix building with SYSCTL=n but DYNAMIC_FTRACE=y
ftrace: Fix build warning
ftrace: move sysctl_ftrace_enabled to ftrace.c
kernel/do_mount_initrd: move real_root_dev sysctls to its own file
kernel/delayacct: move delayacct sysctls to its own file
kernel/acct: move acct sysctls to its own file
kernel/panic: move panic sysctls to its own file
kernel/lockdep: move lockdep sysctls to its own file
mm: move page-writeback sysctls to their own file
mm: move oom_kill sysctls to their own file
kernel/reboot: move reboot sysctls to its own file
sched: Move energy_aware sysctls to topology.c
...
Diffstat (limited to 'kernel/trace')
-rw-r--r-- | kernel/trace/ftrace.c | 211 |
1 files changed, 117 insertions, 94 deletions
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 674add0aafb3..f8db59c3a601 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -86,7 +86,7 @@ struct ftrace_ops ftrace_list_end __read_mostly = { /* ftrace_enabled is a method to turn ftrace on or off */ int ftrace_enabled __read_mostly; -static int last_ftrace_enabled; +static int __maybe_unused last_ftrace_enabled; /* Current function tracing op */ struct ftrace_ops *function_trace_op __read_mostly = &ftrace_list_end; @@ -3065,40 +3065,6 @@ int ftrace_shutdown(struct ftrace_ops *ops, int command) return 0; } -static void ftrace_startup_sysctl(void) -{ - int command; - - if (unlikely(ftrace_disabled)) - return; - - /* Force update next time */ - saved_ftrace_func = NULL; - /* ftrace_start_up is true if we want ftrace running */ - if (ftrace_start_up) { - command = FTRACE_UPDATE_CALLS; - if (ftrace_graph_active) - command |= FTRACE_START_FUNC_RET; - ftrace_startup_enable(command); - } -} - -static void ftrace_shutdown_sysctl(void) -{ - int command; - - if (unlikely(ftrace_disabled)) - return; - - /* ftrace_start_up is true if ftrace is running */ - if (ftrace_start_up) { - command = FTRACE_DISABLE_CALLS; - if (ftrace_graph_active) - command |= FTRACE_STOP_FUNC_RET; - ftrace_run_update_code(command); - } -} - static u64 ftrace_update_time; unsigned long ftrace_update_tot_cnt; unsigned long ftrace_number_of_pages; @@ -7267,9 +7233,6 @@ core_initcall(ftrace_nodyn_init); static inline int ftrace_init_dyn_tracefs(struct dentry *d_tracer) { return 0; } static inline void ftrace_startup_all(int command) { } -# define ftrace_startup_sysctl() do { } while (0) -# define ftrace_shutdown_sysctl() do { } while (0) - static void ftrace_update_trampoline(struct ftrace_ops *ops) { } @@ -7909,62 +7872,6 @@ int unregister_ftrace_function(struct ftrace_ops *ops) } EXPORT_SYMBOL_GPL(unregister_ftrace_function); -static bool is_permanent_ops_registered(void) -{ - struct ftrace_ops *op; - - do_for_each_ftrace_op(op, ftrace_ops_list) { - if (op->flags & FTRACE_OPS_FL_PERMANENT) - return true; - } while_for_each_ftrace_op(op); - - return false; -} - -int -ftrace_enable_sysctl(struct ctl_table *table, int write, - void *buffer, size_t *lenp, loff_t *ppos) -{ - int ret = -ENODEV; - - mutex_lock(&ftrace_lock); - - if (unlikely(ftrace_disabled)) - goto out; - - ret = proc_dointvec(table, write, buffer, lenp, ppos); - - if (ret || !write || (last_ftrace_enabled == !!ftrace_enabled)) - goto out; - - if (ftrace_enabled) { - - /* we are starting ftrace again */ - if (rcu_dereference_protected(ftrace_ops_list, - lockdep_is_held(&ftrace_lock)) != &ftrace_list_end) - update_ftrace_function(); - - ftrace_startup_sysctl(); - - } else { - if (is_permanent_ops_registered()) { - ftrace_enabled = true; - ret = -EBUSY; - goto out; - } - - /* stopping ftrace calls (just send to ftrace_stub) */ - ftrace_trace_function = ftrace_stub; - - ftrace_shutdown_sysctl(); - } - - last_ftrace_enabled = !!ftrace_enabled; - out: - mutex_unlock(&ftrace_lock); - return ret; -} - static int symbols_cmp(const void *a, const void *b) { const char **str_a = (const char **) a; @@ -8026,3 +7933,119 @@ int ftrace_lookup_symbols(const char **sorted_syms, size_t cnt, unsigned long *a return err; return args.found == args.cnt ? 0 : -ESRCH; } + +#ifdef CONFIG_SYSCTL + +#ifdef CONFIG_DYNAMIC_FTRACE +static void ftrace_startup_sysctl(void) +{ + int command; + + if (unlikely(ftrace_disabled)) + return; + + /* Force update next time */ + saved_ftrace_func = NULL; + /* ftrace_start_up is true if we want ftrace running */ + if (ftrace_start_up) { + command = FTRACE_UPDATE_CALLS; + if (ftrace_graph_active) + command |= FTRACE_START_FUNC_RET; + ftrace_startup_enable(command); + } +} + +static void ftrace_shutdown_sysctl(void) +{ + int command; + + if (unlikely(ftrace_disabled)) + return; + + /* ftrace_start_up is true if ftrace is running */ + if (ftrace_start_up) { + command = FTRACE_DISABLE_CALLS; + if (ftrace_graph_active) + command |= FTRACE_STOP_FUNC_RET; + ftrace_run_update_code(command); + } +} +#else +# define ftrace_startup_sysctl() do { } while (0) +# define ftrace_shutdown_sysctl() do { } while (0) +#endif /* CONFIG_DYNAMIC_FTRACE */ + +static bool is_permanent_ops_registered(void) +{ + struct ftrace_ops *op; + + do_for_each_ftrace_op(op, ftrace_ops_list) { + if (op->flags & FTRACE_OPS_FL_PERMANENT) + return true; + } while_for_each_ftrace_op(op); + + return false; +} + +static int +ftrace_enable_sysctl(struct ctl_table *table, int write, + void *buffer, size_t *lenp, loff_t *ppos) +{ + int ret = -ENODEV; + + mutex_lock(&ftrace_lock); + + if (unlikely(ftrace_disabled)) + goto out; + + ret = proc_dointvec(table, write, buffer, lenp, ppos); + + if (ret || !write || (last_ftrace_enabled == !!ftrace_enabled)) + goto out; + + if (ftrace_enabled) { + + /* we are starting ftrace again */ + if (rcu_dereference_protected(ftrace_ops_list, + lockdep_is_held(&ftrace_lock)) != &ftrace_list_end) + update_ftrace_function(); + + ftrace_startup_sysctl(); + + } else { + if (is_permanent_ops_registered()) { + ftrace_enabled = true; + ret = -EBUSY; + goto out; + } + + /* stopping ftrace calls (just send to ftrace_stub) */ + ftrace_trace_function = ftrace_stub; + + ftrace_shutdown_sysctl(); + } + + last_ftrace_enabled = !!ftrace_enabled; + out: + mutex_unlock(&ftrace_lock); + return ret; +} + +static struct ctl_table ftrace_sysctls[] = { + { + .procname = "ftrace_enabled", + .data = &ftrace_enabled, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = ftrace_enable_sysctl, + }, + {} +}; + +static int __init ftrace_sysctl_init(void) +{ + register_sysctl_init("kernel", ftrace_sysctls); + return 0; +} +late_initcall(ftrace_sysctl_init); +#endif |