| Message ID | 20220311112656.25348-1-mark-pk.tsai@mediatek.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | tracing: make tracer_init_tracefs initcall asynchronous | expand |
On Fri, 11 Mar 2022 19:26:56 +0800 Mark-PK Tsai <mark-pk.tsai@mediatek.com> wrote: > tracer_init_tracefs() is slow especially when there are > lots of trace events. > Create a kthread to do tracer_init_tracefs() asynchronously When making comments like this, please provide the benchmarks you used, with the numbers before and after. > to speed up the initialization of kernel and move the > related functions and variables out of init section. Thus we sacrifice memory for boot time. I'd like to also see how much memory is freed from init before and after this patch. > > Signed-off-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com> > --- > fs/tracefs/inode.c | 8 ++++---- > kernel/trace/ftrace.c | 12 ++++++------ > kernel/trace/trace.c | 21 ++++++++++++++++----- > kernel/trace/trace_events.c | 2 +- > 4 files changed, 27 insertions(+), 16 deletions(-) > > diff --git a/fs/tracefs/inode.c b/fs/tracefs/inode.c > index de7252715b12..9a713d6bcb7e 100644 > --- a/fs/tracefs/inode.c > +++ b/fs/tracefs/inode.c > @@ -561,10 +561,10 @@ struct dentry *tracefs_create_dir(const char *name, struct dentry *parent) > * > * Returns the dentry of the instances directory. > */ > -__init struct dentry *tracefs_create_instance_dir(const char *name, > - struct dentry *parent, > - int (*mkdir)(const char *name), > - int (*rmdir)(const char *name)) > +struct dentry *tracefs_create_instance_dir(const char *name, > + struct dentry *parent, > + int (*mkdir)(const char *name), > + int (*rmdir)(const char *name)) > { > struct dentry *dentry; > > diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c > index a4b462b6f944..197630cbd5dd 100644 > --- a/kernel/trace/ftrace.c > +++ b/kernel/trace/ftrace.c > @@ -940,7 +940,7 @@ static const struct file_operations ftrace_profile_fops = { > }; > > /* used to initialize the real stat files */ > -static struct tracer_stat function_stats __initdata = { > +static struct tracer_stat function_stats = { > .name = "functions", > .stat_start = function_stat_start, > .stat_next = function_stat_next, > @@ -949,7 +949,7 @@ static struct tracer_stat function_stats __initdata = { > .stat_show = function_stat_show > }; > > -static __init void ftrace_profile_tracefs(struct dentry *d_tracer) > +static void ftrace_profile_tracefs(struct dentry *d_tracer) > { > struct ftrace_profile_stat *stat; > struct dentry *entry; > @@ -991,7 +991,7 @@ static __init void ftrace_profile_tracefs(struct dentry *d_tracer) > } > > #else /* CONFIG_FUNCTION_PROFILER */ > -static __init void ftrace_profile_tracefs(struct dentry *d_tracer) > +static void ftrace_profile_tracefs(struct dentry *d_tracer) > { > } > #endif /* CONFIG_FUNCTION_PROFILER */ > @@ -6359,7 +6359,7 @@ void ftrace_destroy_filter_files(struct ftrace_ops *ops) > mutex_unlock(&ftrace_lock); > } > > -static __init int ftrace_init_dyn_tracefs(struct dentry *d_tracer) > +static int ftrace_init_dyn_tracefs(struct dentry *d_tracer) > { > > trace_create_file("available_filter_functions", TRACE_MODE_READ, > @@ -7754,8 +7754,8 @@ void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer) > d_tracer, tr, &ftrace_no_pid_fops); > } > > -void __init ftrace_init_tracefs_toplevel(struct trace_array *tr, > - struct dentry *d_tracer) > +void ftrace_init_tracefs_toplevel(struct trace_array *tr, > + struct dentry *d_tracer) > { > /* Only the top level directory has the dyn_tracefs and profile */ > WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL)); > diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c > index eb44418574f9..f55da82060e2 100644 > --- a/kernel/trace/trace.c > +++ b/kernel/trace/trace.c > @@ -9562,10 +9562,10 @@ int tracing_init_dentry(void) > extern struct trace_eval_map *__start_ftrace_eval_maps[]; > extern struct trace_eval_map *__stop_ftrace_eval_maps[]; > > -static struct workqueue_struct *eval_map_wq __initdata; > -static struct work_struct eval_map_work __initdata; > +static struct workqueue_struct *eval_map_wq; > +static struct work_struct eval_map_work; > > -static void __init eval_map_work_func(struct work_struct *work) > +static void eval_map_work_func(struct work_struct *work) > { > int len; > > @@ -9573,7 +9573,7 @@ static void __init eval_map_work_func(struct work_struct *work) > trace_insert_eval_map(NULL, __start_ftrace_eval_maps, len); > } > > -static int __init trace_eval_init(void) > +static int trace_eval_init(void) > { > INIT_WORK(&eval_map_work, eval_map_work_func); > > @@ -9671,7 +9671,7 @@ static struct notifier_block trace_module_nb = { > }; > #endif /* CONFIG_MODULES */ > > -static __init int tracer_init_tracefs(void) > +static int tracefs_init(void *data) > { > int ret; > > @@ -9721,6 +9721,17 @@ static __init int tracer_init_tracefs(void) > return 0; > } > > +static __init int tracer_init_tracefs(void) > +{ > + struct task_struct *thread; > + > + thread = kthread_run(tracefs_init, NULL, "tracefs_init"); > + if (IS_ERR(thread)) > + return PTR_ERR(thread); > + > + return 0; > +} > + > fs_initcall(tracer_init_tracefs); > > static int trace_panic_handler(struct notifier_block *this, > diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c > index 3147614c1812..fe055bef1e8f 100644 > --- a/kernel/trace/trace_events.c > +++ b/kernel/trace/trace_events.c > @@ -3687,7 +3687,7 @@ static __init int event_trace_init_fields(void) > return 0; > } > > -__init int event_trace_init(void) > +int event_trace_init(void) > { > struct trace_array *tr; > struct dentry *entry; Hmm, this calls early_event_tracer() which is also in __init. Looks like there's going to be a ripple effect due to this change. If we want to go this route, then first a change must be made to remove the needed functions from init, and then see if we can consolidate it. As there are some init functions that are duplicated for init purposes. -- Steve
Hi Mark-PK,
I love your patch! Perhaps something to improve:
[auto build test WARNING on rostedt-trace/for-next]
[also build test WARNING on v5.17-rc7 next-20220310]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/0day-ci/linux/commits/Mark-PK-Tsai/tracing-make-tracer_init_tracefs-initcall-asynchronous/20220311-192857
base: https://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace.git for-next
config: sh-randconfig-r031-20220311 (https://download.01.org/0day-ci/archive/20220312/202203120105.7vxKh4v9-lkp@intel.com/config)
compiler: sh4-linux-gcc (GCC) 11.2.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/0day-ci/linux/commit/134c5fb991a16bf28b500e8e52296447013b5b01
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Mark-PK-Tsai/tracing-make-tracer_init_tracefs-initcall-asynchronous/20220311-192857
git checkout 134c5fb991a16bf28b500e8e52296447013b5b01
# save the config file to linux build tree
mkdir build_dir
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross O=build_dir ARCH=sh SHELL=/bin/bash
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
All warnings (new ones prefixed by >>, old ones prefixed by <<):
>> WARNING: modpost: vmlinux.o(.text+0x144bfc): Section mismatch in reference from the function tracefs_init() to the function .init.text:set_reset_devices()
The function tracefs_init() references
the function __init set_reset_devices().
This is often because tracefs_init lacks a __init
annotation or the annotation of set_reset_devices is wrong.
---
0-DAY CI Kernel Test Service
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
Hi Mark-PK,
I love your patch! Perhaps something to improve:
[auto build test WARNING on rostedt-trace/for-next]
[also build test WARNING on v5.17-rc7 next-20220310]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/0day-ci/linux/commits/Mark-PK-Tsai/tracing-make-tracer_init_tracefs-initcall-asynchronous/20220311-192857
base: https://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace.git for-next
config: riscv-randconfig-r042-20220310 (https://download.01.org/0day-ci/archive/20220312/202203120304.sJ9EJI90-lkp@intel.com/config)
compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project 276ca87382b8f16a65bddac700202924228982f6)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# install riscv cross compiling tool for clang build
# apt-get install binutils-riscv64-linux-gnu
# https://github.com/0day-ci/linux/commit/134c5fb991a16bf28b500e8e52296447013b5b01
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Mark-PK-Tsai/tracing-make-tracer_init_tracefs-initcall-asynchronous/20220311-192857
git checkout 134c5fb991a16bf28b500e8e52296447013b5b01
# save the config file to linux build tree
mkdir build_dir
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=riscv SHELL=/bin/bash
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
All warnings (new ones prefixed by >>, old ones prefixed by <<):
>> WARNING: modpost: vmlinux.o(.text+0xa792a): Section mismatch in reference from the function tracefs_init() to the function .init.text:create_trace_instances()
The function tracefs_init() references
the function __init create_trace_instances().
This is often because tracefs_init lacks a __init
annotation or the annotation of create_trace_instances is wrong.
--
>> WARNING: modpost: vmlinux.o(.text+0xade5e): Section mismatch in reference from the function event_trace_init() to the function .init.text:early_event_add_tracer()
The function event_trace_init() references
the function __init early_event_add_tracer().
This is often because event_trace_init lacks a __init
annotation or the annotation of early_event_add_tracer is wrong.
---
0-DAY CI Kernel Test Service
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
> On Fri, 11 Mar 2022 19:26:56 +0800 > Mark-PK Tsai <mark-pk.tsai@mediatek.com> wrote: > > > tracer_init_tracefs() is slow especially when there are > > lots of trace events. > > Create a kthread to do tracer_init_tracefs() asynchronously > > When making comments like this, please provide the benchmarks you used, > with the numbers before and after. I've retest it with kernel 5.17-rc7 on my arm64 board, and I found that the critical path is trace_eval_sync which spend about 430 ms. It's almost half of the time the do_initcalls spends. Below is the test result. before after tracer_init_tracefs 29872 us 66 us trace_eval_sync 429695 us 459370 us do_initcalls 797818 us 799890 us I locally skip trace_eval_sync and got below result. before after diff do_initcalls 359252 us 341725 us -17527 us So beside this patch, could we add a kernel parameter or a option to skip it when it doesn't used right after kernel boot? > > > to speed up the initialization of kernel and move the > > related functions and variables out of init section. > > Thus we sacrifice memory for boot time. I'd like to also see how much > memory is freed from init before and after this patch. > Below is the INIT_TEXT and INIT_DATA diff: before after diff INIT_TEXT 7F290 7EDAC -0x4e4 bytes INIT_DATA 116FE8 116FE8 0 bytes And the init section is 64K aligned on arm64 so that when I test on my platform, the actual memory freed by initmem_free() have no diffrence after apply this patch. #define SEGMENT_ALIGN SZ_64K > > > > Signed-off-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com> > > --- > > fs/tracefs/inode.c | 8 ++++---- > > kernel/trace/ftrace.c | 12 ++++++------ > > kernel/trace/trace.c | 21 ++++++++++++++++----- > > kernel/trace/trace_events.c | 2 +- > > 4 files changed, 27 insertions(+), 16 deletions(-) > > > > diff --git a/fs/tracefs/inode.c b/fs/tracefs/inode.c > > index de7252715b12..9a713d6bcb7e 100644 > > --- a/fs/tracefs/inode.c > > +++ b/fs/tracefs/inode.c > > @@ -561,10 +561,10 @@ struct dentry *tracefs_create_dir(const char *name, struct dentry *parent) > > * > > * Returns the dentry of the instances directory. > > */ > > -__init struct dentry *tracefs_create_instance_dir(const char *name, > > - struct dentry *parent, > > - int (*mkdir)(const char *name), > > - int (*rmdir)(const char *name)) > > +struct dentry *tracefs_create_instance_dir(const char *name, > > + struct dentry *parent, > > + int (*mkdir)(const char *name), > > + int (*rmdir)(const char *name)) > > { > > struct dentry *dentry; > > > > diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c > > index a4b462b6f944..197630cbd5dd 100644 > > --- a/kernel/trace/ftrace.c > > +++ b/kernel/trace/ftrace.c > > @@ -940,7 +940,7 @@ static const struct file_operations ftrace_profile_fops = { > > }; > > > > /* used to initialize the real stat files */ > > -static struct tracer_stat function_stats __initdata = { > > +static struct tracer_stat function_stats = { > > .name = "functions", > > .stat_start = function_stat_start, > > .stat_next = function_stat_next, > > @@ -949,7 +949,7 @@ static struct tracer_stat function_stats __initdata = { > > .stat_show = function_stat_show > > }; > > > > -static __init void ftrace_profile_tracefs(struct dentry *d_tracer) > > +static void ftrace_profile_tracefs(struct dentry *d_tracer) > > { > > struct ftrace_profile_stat *stat; > > struct dentry *entry; > > @@ -991,7 +991,7 @@ static __init void ftrace_profile_tracefs(struct dentry *d_tracer) > > } > > > > #else /* CONFIG_FUNCTION_PROFILER */ > > -static __init void ftrace_profile_tracefs(struct dentry *d_tracer) > > +static void ftrace_profile_tracefs(struct dentry *d_tracer) > > { > > } > > #endif /* CONFIG_FUNCTION_PROFILER */ > > @@ -6359,7 +6359,7 @@ void ftrace_destroy_filter_files(struct ftrace_ops *ops) > > mutex_unlock(&ftrace_lock); > > } > > > > -static __init int ftrace_init_dyn_tracefs(struct dentry *d_tracer) > > +static int ftrace_init_dyn_tracefs(struct dentry *d_tracer) > > { > > > > trace_create_file("available_filter_functions", TRACE_MODE_READ, > > @@ -7754,8 +7754,8 @@ void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer) > > d_tracer, tr, &ftrace_no_pid_fops); > > } > > > > -void __init ftrace_init_tracefs_toplevel(struct trace_array *tr, > > - struct dentry *d_tracer) > > +void ftrace_init_tracefs_toplevel(struct trace_array *tr, > > + struct dentry *d_tracer) > > { > > /* Only the top level directory has the dyn_tracefs and profile */ > > WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL)); > > diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c > > index eb44418574f9..f55da82060e2 100644 > > --- a/kernel/trace/trace.c > > +++ b/kernel/trace/trace.c > > @@ -9562,10 +9562,10 @@ int tracing_init_dentry(void) > > extern struct trace_eval_map *__start_ftrace_eval_maps[]; > > extern struct trace_eval_map *__stop_ftrace_eval_maps[]; > > > > -static struct workqueue_struct *eval_map_wq __initdata; > > -static struct work_struct eval_map_work __initdata; > > +static struct workqueue_struct *eval_map_wq; > > +static struct work_struct eval_map_work; > > > > -static void __init eval_map_work_func(struct work_struct *work) > > +static void eval_map_work_func(struct work_struct *work) > > { > > int len; > > > > @@ -9573,7 +9573,7 @@ static void __init eval_map_work_func(struct work_struct *work) > > trace_insert_eval_map(NULL, __start_ftrace_eval_maps, len); > > } > > > > -static int __init trace_eval_init(void) > > +static int trace_eval_init(void) > > { > > INIT_WORK(&eval_map_work, eval_map_work_func); > > > > @@ -9671,7 +9671,7 @@ static struct notifier_block trace_module_nb = { > > }; > > #endif /* CONFIG_MODULES */ > > > > -static __init int tracer_init_tracefs(void) > > +static int tracefs_init(void *data) > > { > > int ret; > > > > @@ -9721,6 +9721,17 @@ static __init int tracer_init_tracefs(void) > > return 0; > > } > > > > +static __init int tracer_init_tracefs(void) > > +{ > > + struct task_struct *thread; > > + > > + thread = kthread_run(tracefs_init, NULL, "tracefs_init"); > > + if (IS_ERR(thread)) > > + return PTR_ERR(thread); > > + > > + return 0; > > +} > > + > > fs_initcall(tracer_init_tracefs); > > > > static int trace_panic_handler(struct notifier_block *this, > > diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c > > index 3147614c1812..fe055bef1e8f 100644 > > --- a/kernel/trace/trace_events.c > > +++ b/kernel/trace/trace_events.c > > @@ -3687,7 +3687,7 @@ static __init int event_trace_init_fields(void) > > return 0; > > } > > > > -__init int event_trace_init(void) > > +int event_trace_init(void) > > { > > struct trace_array *tr; > > struct dentry *entry; > > Hmm, this calls early_event_tracer() which is also in __init. Looks like > there's going to be a ripple effect due to this change. > > If we want to go this route, then first a change must be made to remove the > needed functions from init, and then see if we can consolidate it. As there > are some init functions that are duplicated for init purposes. Got it! > > -- Steve
> > On Fri, 11 Mar 2022 19:26:56 +0800 > > Mark-PK Tsai <mark-pk.tsai@mediatek.com> wrote: > > > > > tracer_init_tracefs() is slow especially when there are > > > lots of trace events. > > > Create a kthread to do tracer_init_tracefs() asynchronously > > > > When making comments like this, please provide the benchmarks you used, > > with the numbers before and after. > > I've retest it with kernel 5.17-rc7 on my arm64 board, and I found that > the critical path is trace_eval_sync which spend about 430 ms. > It's almost half of the time the do_initcalls spends. > Below is the test result. > > before after > tracer_init_tracefs 29872 us 66 us > trace_eval_sync 429695 us 459370 us > do_initcalls 797818 us 799890 us > > I locally skip trace_eval_sync and got below result. > > before after diff > do_initcalls 359252 us 341725 us -17527 us > > So beside this patch, could we add a kernel parameter or a > option to skip it when it doesn't used right after kernel boot? > Please ignore this. I do more tests and found that ftrace_eval_maps is in INIT_DATA. So the eval_wq may crash if it doesn't finish before init mem is freed. And ftrace_eval_maps is big when there are lots of trace event (About 6KB with arch/arm64/defconfig). So it seems not a good idea to remove all the needed funcs from init. So please review v2 [1] I've just push which queue the tracer_init_tracefs() to eval_map_wq. [1]: https://lore.kernel.org/lkml/20220316151639.9216-1-mark-pk.tsai@mediatek.com/ > > > > > to speed up the initialization of kernel and move the > > > related functions and variables out of init section. > > > > Thus we sacrifice memory for boot time. I'd like to also see how much > > memory is freed from init before and after this patch. > > > > Below is the INIT_TEXT and INIT_DATA diff: > > before after diff > INIT_TEXT 7F290 7EDAC -0x4e4 bytes > INIT_DATA 116FE8 116FE8 0 bytes > > And the init section is 64K aligned on arm64 so that when I test > on my platform, the actual memory freed by initmem_free() have no > diffrence after apply this patch. > > #define SEGMENT_ALIGN SZ_64K > > > > > > > static int trace_panic_handler(struct notifier_block *this, > > > diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c > > > index 3147614c1812..fe055bef1e8f 100644 > > > --- a/kernel/trace/trace_events.c > > > +++ b/kernel/trace/trace_events.c > > > @@ -3687,7 +3687,7 @@ static __init int event_trace_init_fields(void) > > > return 0; > > > } > > > > > > -__init int event_trace_init(void) > > > +int event_trace_init(void) > > > { > > > struct trace_array *tr; > > > struct dentry *entry; > > > > Hmm, this calls early_event_tracer() which is also in __init. Looks like > > there's going to be a ripple effect due to this change. > > > > If we want to go this route, then first a change must be made to remove the > > needed functions from init, and then see if we can consolidate it. As there > > are some init functions that are duplicated for init purposes. > > Got it! >
diff --git a/fs/tracefs/inode.c b/fs/tracefs/inode.c index de7252715b12..9a713d6bcb7e 100644 --- a/fs/tracefs/inode.c +++ b/fs/tracefs/inode.c @@ -561,10 +561,10 @@ struct dentry *tracefs_create_dir(const char *name, struct dentry *parent) * * Returns the dentry of the instances directory. */ -__init struct dentry *tracefs_create_instance_dir(const char *name, - struct dentry *parent, - int (*mkdir)(const char *name), - int (*rmdir)(const char *name)) +struct dentry *tracefs_create_instance_dir(const char *name, + struct dentry *parent, + int (*mkdir)(const char *name), + int (*rmdir)(const char *name)) { struct dentry *dentry; diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index a4b462b6f944..197630cbd5dd 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -940,7 +940,7 @@ static const struct file_operations ftrace_profile_fops = { }; /* used to initialize the real stat files */ -static struct tracer_stat function_stats __initdata = { +static struct tracer_stat function_stats = { .name = "functions", .stat_start = function_stat_start, .stat_next = function_stat_next, @@ -949,7 +949,7 @@ static struct tracer_stat function_stats __initdata = { .stat_show = function_stat_show }; -static __init void ftrace_profile_tracefs(struct dentry *d_tracer) +static void ftrace_profile_tracefs(struct dentry *d_tracer) { struct ftrace_profile_stat *stat; struct dentry *entry; @@ -991,7 +991,7 @@ static __init void ftrace_profile_tracefs(struct dentry *d_tracer) } #else /* CONFIG_FUNCTION_PROFILER */ -static __init void ftrace_profile_tracefs(struct dentry *d_tracer) +static void ftrace_profile_tracefs(struct dentry *d_tracer) { } #endif /* CONFIG_FUNCTION_PROFILER */ @@ -6359,7 +6359,7 @@ void ftrace_destroy_filter_files(struct ftrace_ops *ops) mutex_unlock(&ftrace_lock); } -static __init int ftrace_init_dyn_tracefs(struct dentry *d_tracer) +static int ftrace_init_dyn_tracefs(struct dentry *d_tracer) { trace_create_file("available_filter_functions", TRACE_MODE_READ, @@ -7754,8 +7754,8 @@ void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer) d_tracer, tr, &ftrace_no_pid_fops); } -void __init ftrace_init_tracefs_toplevel(struct trace_array *tr, - struct dentry *d_tracer) +void ftrace_init_tracefs_toplevel(struct trace_array *tr, + struct dentry *d_tracer) { /* Only the top level directory has the dyn_tracefs and profile */ WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL)); diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index eb44418574f9..f55da82060e2 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -9562,10 +9562,10 @@ int tracing_init_dentry(void) extern struct trace_eval_map *__start_ftrace_eval_maps[]; extern struct trace_eval_map *__stop_ftrace_eval_maps[]; -static struct workqueue_struct *eval_map_wq __initdata; -static struct work_struct eval_map_work __initdata; +static struct workqueue_struct *eval_map_wq; +static struct work_struct eval_map_work; -static void __init eval_map_work_func(struct work_struct *work) +static void eval_map_work_func(struct work_struct *work) { int len; @@ -9573,7 +9573,7 @@ static void __init eval_map_work_func(struct work_struct *work) trace_insert_eval_map(NULL, __start_ftrace_eval_maps, len); } -static int __init trace_eval_init(void) +static int trace_eval_init(void) { INIT_WORK(&eval_map_work, eval_map_work_func); @@ -9671,7 +9671,7 @@ static struct notifier_block trace_module_nb = { }; #endif /* CONFIG_MODULES */ -static __init int tracer_init_tracefs(void) +static int tracefs_init(void *data) { int ret; @@ -9721,6 +9721,17 @@ static __init int tracer_init_tracefs(void) return 0; } +static __init int tracer_init_tracefs(void) +{ + struct task_struct *thread; + + thread = kthread_run(tracefs_init, NULL, "tracefs_init"); + if (IS_ERR(thread)) + return PTR_ERR(thread); + + return 0; +} + fs_initcall(tracer_init_tracefs); static int trace_panic_handler(struct notifier_block *this, diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index 3147614c1812..fe055bef1e8f 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -3687,7 +3687,7 @@ static __init int event_trace_init_fields(void) return 0; } -__init int event_trace_init(void) +int event_trace_init(void) { struct trace_array *tr; struct dentry *entry;
tracer_init_tracefs() is slow especially when there are lots of trace events. Create a kthread to do tracer_init_tracefs() asynchronously to speed up the initialization of kernel and move the related functions and variables out of init section. Signed-off-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com> --- fs/tracefs/inode.c | 8 ++++---- kernel/trace/ftrace.c | 12 ++++++------ kernel/trace/trace.c | 21 ++++++++++++++++----- kernel/trace/trace_events.c | 2 +- 4 files changed, 27 insertions(+), 16 deletions(-)