[RFC PATCH 5/5] pgo: Cleanup code in pgo/fs.c

From: Jarmo Tiitto
Date: Fri Jun 11 2021 - 23:36:46 EST


Cleanups to comments and punctuation.
Cleanup return path in pgo_module_init.

Signed-off-by: Jarmo Tiitto <jarmo.tiitto@xxxxxxxxx>
---
kernel/pgo/fs.c | 47 +++++++++++++++++++++++------------------------
1 file changed, 23 insertions(+), 24 deletions(-)

diff --git a/kernel/pgo/fs.c b/kernel/pgo/fs.c
index 98b982245b58..855d5e3050fa 100644
--- a/kernel/pgo/fs.c
+++ b/kernel/pgo/fs.c
@@ -294,7 +294,7 @@ static int prf_open(struct inode *inode, struct file *file)
int err = -EINVAL;

if (WARN_ON(!inode->i_private)) {
- /* bug: inode was not initialized by us */
+ /* Bug: inode was not initialized by us. */
return err;
}

@@ -302,7 +302,7 @@ static int prf_open(struct inode *inode, struct file *file)
if (!data)
return -ENOMEM;

- /* Get prf_object of this inode */
+ /* Get prf_object of this inode. */
data->core = inode->i_private;

/* Get initial buffer size. */
@@ -425,17 +425,17 @@ static void pgo_module_init(struct module *mod)
char fname[MODULE_NAME_LEN + 9]; /* +strlen(".profraw") */
unsigned long flags;

- /* add new prf_object entry for the module */
+ /* Add new prf_object entry for the module. */
po = kzalloc(sizeof(*po), GFP_KERNEL);
if (!po)
- goto out;
+ return; /* -ENOMEM */

po->mod_name = mod->name;

fname[0] = 0;
snprintf(fname, sizeof(fname), "%s.profraw", po->mod_name);

- /* setup prf_object sections */
+ /* Setup prf_object sections. */
po->data = mod->prf_data;
po->data_num = prf_get_count(mod->prf_data,
(char *)mod->prf_data + mod->prf_data_size, sizeof(po->data[0]));
@@ -452,20 +452,19 @@ static void pgo_module_init(struct module *mod)
po->vnds_num = prf_get_count(mod->prf_vnds,
(char *)mod->prf_vnds + mod->prf_vnds_size, sizeof(po->vnds[0]));

- /* create debugfs entry */
+ /* Create debugfs entry. */
po->file = debugfs_create_file(fname, 0600, directory, po, &prf_fops);
if (!po->file) {
pr_err("Failed to setup module pgo: %s", fname);
kfree(po);
- goto out;
- }

- /* finally enable profiling for the module */
- flags = prf_list_lock();
- list_add_tail_rcu(&po->link, &prf_list);
- prf_list_unlock(flags);
+ } else {
+ /* Finally enable profiling for the module. */
+ flags = prf_list_lock();
+ list_add_tail_rcu(&po->link, &prf_list);
+ prf_list_unlock(flags);
+ }

-out:
return;
}

@@ -477,33 +476,33 @@ static int pgo_module_notifier(struct notifier_block *nb, unsigned long event,
unsigned long flags;

if (event == MODULE_STATE_LIVE) {
- /* does the module have profiling info? */
+ /* Does the module have profiling info? */
if (mod->prf_data
&& mod->prf_cnts
&& mod->prf_names
&& mod->prf_vnds) {

- /* setup module profiling */
+ /* Setup module profiling. */
pgo_module_init(mod);
}
}

if (event == MODULE_STATE_GOING) {
- /* find the prf_object from the list */
+ /* Find the prf_object from the list. */
rcu_read_lock();

list_for_each_entry_rcu(po, &prf_list, link) {
if (strcmp(po->mod_name, mod->name) == 0)
goto out_unlock;
}
- /* no such module */
+ /* No such module. */
po = NULL;

out_unlock:
rcu_read_unlock();

if (po) {
- /* remove from profiled modules */
+ /* Remove from profiled modules. */
flags = prf_list_lock();
list_del_rcu(&po->link);
prf_list_unlock(flags);
@@ -511,7 +510,7 @@ static int pgo_module_notifier(struct notifier_block *nb, unsigned long event,
debugfs_remove(po->file);
po->file = NULL;

- /* cleanup memory */
+ /* Cleanup memory. */
kfree_rcu(po, rcu);
}
}
@@ -528,7 +527,7 @@ static int __init pgo_init(void)
{
unsigned long flags;

- /* Init profiler vmlinux core entry */
+ /* Init profiler vmlinux core entry. */
memset(&prf_vmlinux, 0, sizeof(prf_vmlinux));
prf_vmlinux.data = __llvm_prf_data_start;
prf_vmlinux.data_num = prf_get_count(__llvm_prf_data_start,
@@ -546,7 +545,7 @@ static int __init pgo_init(void)
prf_vmlinux.vnds_num = prf_get_count(__llvm_prf_vnds_start,
__llvm_prf_vnds_end, sizeof(__llvm_prf_vnds_start[0]));

- /* enable profiling */
+ /* Enable profiling. */
flags = prf_list_lock();
prf_vmlinux.mod_name = "vmlinux";
list_add_tail_rcu(&prf_vmlinux.link, &prf_list);
@@ -565,10 +564,10 @@ static int __init pgo_init(void)
&prf_reset_fops))
goto err_remove;

- /* register module notifer */
+ /* Register module notifer. */
register_module_notifier(&pgo_module_nb);

- /* show notice why the system slower: */
+ /* Show notice why the system slower: */
pr_notice("Clang PGO instrumentation is active.");

return 0;
@@ -581,7 +580,7 @@ static int __init pgo_init(void)
/* Remove debugfs entries. */
static void __exit pgo_exit(void)
{
- /* unsubscribe the notifier and do cleanup. */
+ /* Unsubscribe the notifier and do cleanup. */
unregister_module_notifier(&pgo_module_nb);

debugfs_remove_recursive(directory);
--
2.32.0