From: Qiujun Huang <hqjagain@gmail.com>
To: rostedt@goodmis.org, mingo@redhat.com, linux-kernel@vger.kernel.org
Cc: Qiujun Huang <hqjagain@gmail.com>
Subject: [PATCH] ring-buffer: Add rb_check_bpage in __rb_allocate_pages
Date: Wed, 14 Oct 2020 23:16:14 +0800 [thread overview]
Message-ID: <20201014151614.29804-1-hqjagain@gmail.com> (raw)
It may be better to check each page is aligned by 4 bytes. The 2
least significant bits of the address will be used as flags.
Signed-off-by: Qiujun Huang <hqjagain@gmail.com>
---
kernel/trace/ring_buffer.c | 11 +++++++----
1 file changed, 7 insertions(+), 4 deletions(-)
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 93ef0ab6ea20..9dec7d58b177 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -1420,7 +1420,8 @@ static int rb_check_pages(struct ring_buffer_per_cpu *cpu_buffer)
return 0;
}
-static int __rb_allocate_pages(long nr_pages, struct list_head *pages, int cpu)
+static int __rb_allocate_pages(struct ring_buffer_per_cpu *cpu_buffer,
+ long nr_pages, struct list_head *pages, int cpu)
{
struct buffer_page *bpage, *tmp;
bool user_thread = current->mm != NULL;
@@ -1464,6 +1465,8 @@ static int __rb_allocate_pages(long nr_pages, struct list_head *pages, int cpu)
if (!bpage)
goto free_pages;
+ rb_check_bpage(cpu_buffer, bpage);
+
list_add(&bpage->list, pages);
page = alloc_pages_node(cpu_to_node(cpu), mflags, 0);
@@ -1498,7 +1501,7 @@ static int rb_allocate_pages(struct ring_buffer_per_cpu *cpu_buffer,
WARN_ON(!nr_pages);
- if (__rb_allocate_pages(nr_pages, &pages, cpu_buffer->cpu))
+ if (__rb_allocate_pages(cpu_buffer, nr_pages, &pages, cpu_buffer->cpu))
return -ENOMEM;
/*
@@ -2007,7 +2010,7 @@ int ring_buffer_resize(struct trace_buffer *buffer, unsigned long size,
* allocated without receiving ENOMEM
*/
INIT_LIST_HEAD(&cpu_buffer->new_pages);
- if (__rb_allocate_pages(cpu_buffer->nr_pages_to_update,
+ if (__rb_allocate_pages(cpu_buffer, cpu_buffer->nr_pages_to_update,
&cpu_buffer->new_pages, cpu)) {
/* not enough memory for new pages */
err = -ENOMEM;
@@ -2073,7 +2076,7 @@ int ring_buffer_resize(struct trace_buffer *buffer, unsigned long size,
INIT_LIST_HEAD(&cpu_buffer->new_pages);
if (cpu_buffer->nr_pages_to_update > 0 &&
- __rb_allocate_pages(cpu_buffer->nr_pages_to_update,
+ __rb_allocate_pages(cpu_buffer, cpu_buffer->nr_pages_to_update,
&cpu_buffer->new_pages, cpu_id)) {
err = -ENOMEM;
goto out_err;
--
2.17.1
next reply other threads:[~2020-10-14 15:16 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-10-14 15:16 Qiujun Huang [this message]
2020-10-14 15:38 ` [PATCH] ring-buffer: Add rb_check_bpage in __rb_allocate_pages Steven Rostedt
2020-10-14 15:48 ` Qiujun Huang
2020-10-14 16:11 ` Steven Rostedt
2020-10-14 16:32 ` Qiujun Huang
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