shinys000114/linux
1
0
Fork 0
mirror of https://github.com/hardkernel/linux.git synced 2026-03-25 20:10:23 +09:00
Code Issues Packages Projects Releases Wiki Activity

ANDROID: mm: page_pinner: change pinner buffer size

Browse Source 
Introduce $debugfs/page_pinner/buffer_size to change
buffer_size on demand. The change of buffer_size will
reset the buffer.

Bug: 218731671
Signed-off-by: Minchan Kim <minchan@google.com>
Change-Id: I505cdc2ee29aa0c6ed4e2dc2c0b6fcff77c388e4
This commit is contained in:
Minchan Kim
2022-03-29 14:47:40 -07:00
committed by Todd Kjos
parent b8a18e852e
commit 01edbc91e2
1 changed files with 41 additions and 7 deletions
Download Patch File Download Diff File Expand all files Collapse all files

48
mm/page_pinner.c
View File

@@ -15,7 +15,7 @@
#include "internal.h"
#define PAGE_PINNER_STACK_DEPTH 16
#define PP_BUF_SIZE 4096
static unsigned long pp_buf_size = 4096;
struct page_pinner {
depot_stack_handle_t handle;
@@ -47,7 +47,7 @@ struct captured_pinner {
struct page_pinner_buffer {
spinlock_t lock;
unsigned int index;
unsigned long index;
struct captured_pinner *buffer;
};
@@ -135,7 +135,7 @@ static void add_record(struct page_pinner_buffer *pp_buf,
spin_lock_irqsave(&pp_buf->lock, flags);
idx = pp_buf->index++;
pp_buf->index %= PP_BUF_SIZE;
pp_buf->index %= pp_buf_size;
pp_buf->buffer[idx] = *record;
spin_unlock_irqrestore(&pp_buf->lock, flags);
}
@@ -343,6 +343,7 @@ EXPORT_SYMBOL_GPL(__page_pinner_put_page);
static ssize_t read_buffer(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
{
u64 tmp;
loff_t i, idx;
struct captured_pinner record;
unsigned long flags;
@@ -350,7 +351,7 @@ static ssize_t read_buffer(struct file *file, char __user *buf,
if (!static_branch_unlikely(&failure_tracking))
return -EINVAL;
if (*ppos >= PP_BUF_SIZE)
if (*ppos >= pp_buf_size)
return 0;
i = *ppos;
@@ -360,8 +361,8 @@ static ssize_t read_buffer(struct file *file, char __user *buf,
* reading the records in the reverse order with newest one
* being read first followed by older ones
*/
idx = (pp_buffer.index - 1 - i + PP_BUF_SIZE) %
PP_BUF_SIZE;
tmp = pp_buffer.index - 1 - i + pp_buf_size;
idx = do_div(tmp, pp_buf_size);
spin_lock_irqsave(&pp_buffer.lock, flags);
record = pp_buffer.buffer[idx];
@@ -397,6 +398,35 @@ DEFINE_DEBUGFS_ATTRIBUTE(failure_tracking_fops,
failure_tracking_get,
failure_tracking_set, "%llu\n");
static int buffer_size_set(void *data, u64 val)
{
unsigned long flags;
struct captured_pinner *new, *old;
new = kvmalloc_array(val, sizeof(*new), GFP_KERNEL);
if (!new)
return -ENOMEM;
spin_lock_irqsave(&pp_buffer.lock, flags);
old = pp_buffer.buffer;
pp_buffer.buffer = new;
pp_buffer.index = 0;
pp_buf_size = val;
spin_unlock_irqrestore(&pp_buffer.lock, flags);
kvfree(old);
return 0;
}
static int buffer_size_get(void *data, u64 *val)
{
*val = pp_buf_size;
return 0;
}
DEFINE_DEBUGFS_ATTRIBUTE(buffer_size_fops,
buffer_size_get,
buffer_size_set, "%llu\n");
static int __init page_pinner_init(void)
{
struct dentry *pp_debugfs_root;
@@ -404,7 +434,7 @@ static int __init page_pinner_init(void)
if (!static_branch_unlikely(&page_pinner_inited))
return 0;
pp_buffer.buffer = kvmalloc_array(PP_BUF_SIZE, sizeof(*pp_buffer.buffer),
pp_buffer.buffer = kvmalloc_array(pp_buf_size, sizeof(*pp_buffer.buffer),
GFP_KERNEL);
if (!pp_buffer.buffer) {
pr_info("page_pinner disabled due to \n");
@@ -425,6 +455,10 @@ static int __init page_pinner_init(void)
debugfs_create_file("failure_tracking", 0644,
pp_debugfs_root, NULL,
&failure_tracking_fops);
debugfs_create_file("buffer_size", 0644,
pp_debugfs_root, NULL,
&buffer_size_fops);
return 0;
}
late_initcall(page_pinner_init)