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ring-buffer: Use subbuf_order for buffer page masking

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The comparisons to PAGE_SIZE were all converted to use the
buffer->subbuf_order, but the use of PAGE_MASK was missed.

Convert all the PAGE_MASK usages over to:

  (PAGE_SIZE << cpu_buffer->buffer->subbuf_order) - 1

Link: https://lore.kernel.org/linux-trace-kernel/20231219173800.66eefb7a@gandalf.local.home

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Tzvetomir Stoyanov <tz.stoyanov@gmail.com>
Cc: Vincent Donnefort <vdonnefort@google.com>
Cc: Kent Overstreet <kent.overstreet@gmail.com>
Fixes: 139f840021 ("ring-buffer: Page size per ring buffer")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
This commit is contained in:
Steven Rostedt (Google) 2023-12-19 17:38:00 -05:00
parent 2f84b39f48
commit 3cb3091138
1 changed files with 11 additions and 8 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

19
kernel/trace/ring_buffer.c
View file

@ -2269,11 +2269,13 @@ rb_commit_index(struct ring_buffer_per_cpu *cpu_buffer)
}
static __always_inline unsigned
rb_event_index(struct ring_buffer_event *event)
rb_event_index(struct ring_buffer_per_cpu *cpu_buffer, struct ring_buffer_event *event)
{
unsigned long addr = (unsigned long)event;
return (addr & ~PAGE_MASK) - BUF_PAGE_HDR_SIZE;
addr &= (PAGE_SIZE << cpu_buffer->buffer->subbuf_order) - 1;
return addr - BUF_PAGE_HDR_SIZE;
}
static void rb_inc_iter(struct ring_buffer_iter *iter)
@ -2646,7 +2648,8 @@ rb_move_tail(struct ring_buffer_per_cpu *cpu_buffer,
/* Slow path */
static struct ring_buffer_event *
rb_add_time_stamp(struct ring_buffer_event *event, u64 delta, bool abs)
rb_add_time_stamp(struct ring_buffer_per_cpu *cpu_buffer,
struct ring_buffer_event *event, u64 delta, bool abs)
{
if (abs)
event->type_len = RINGBUF_TYPE_TIME_STAMP;
@ -2654,7 +2657,7 @@ rb_add_time_stamp(struct ring_buffer_event *event, u64 delta, bool abs)
event->type_len = RINGBUF_TYPE_TIME_EXTEND;
/* Not the first event on the page, or not delta? */
if (abs || rb_event_index(event)) {
if (abs || rb_event_index(cpu_buffer, event)) {
event->time_delta = delta & TS_MASK;
event->array[0] = delta >> TS_SHIFT;
} else {
@ -2728,7 +2731,7 @@ static void rb_add_timestamp(struct ring_buffer_per_cpu *cpu_buffer,
if (!abs)
info->delta = 0;
}
*event = rb_add_time_stamp(*event, info->delta, abs);
*event = rb_add_time_stamp(cpu_buffer, *event, info->delta, abs);
*length -= RB_LEN_TIME_EXTEND;
*delta = 0;
}
@ -2812,10 +2815,10 @@ rb_try_to_discard(struct ring_buffer_per_cpu *cpu_buffer,
struct buffer_page *bpage;
unsigned long addr;
new_index = rb_event_index(event);
new_index = rb_event_index(cpu_buffer, event);
old_index = new_index + rb_event_ts_length(event);
addr = (unsigned long)event;
addr &= PAGE_MASK;
addr &= ~((PAGE_SIZE << cpu_buffer->buffer->subbuf_order) - 1);
bpage = READ_ONCE(cpu_buffer->tail_page);
@ -3726,7 +3729,7 @@ rb_decrement_entry(struct ring_buffer_per_cpu *cpu_buffer,
struct buffer_page *bpage = cpu_buffer->commit_page;
struct buffer_page *start;
addr &= PAGE_MASK;
addr &= ~((PAGE_SIZE << cpu_buffer->buffer->subbuf_order) - 1);
/* Do the likely case first */
if (likely(bpage->page == (void *)addr)) {