Revert "perf/core: Add a new read format to get a number of lost samples"

This reverts commit 84ca356ec8 which is
commit 119a784c81270eb88e573174ed2209225d646656 upstream.

It breaks the Android kernel abi and can be brought back in the future
in an abi-safe way if it is really needed.

Bug: 161946584
Change-Id: I9f973774a99437a3dcfecf32eff8e7ddcfd418ed
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
This commit is contained in:
Greg Kroah-Hartman 2023-12-18 19:01:15 +00:00
parent 8eb4011508
commit 50aa4f43a9
4 changed files with 5 additions and 28 deletions

View File

@ -702,8 +702,6 @@ struct perf_event {
struct pid_namespace *ns;
u64 id;
atomic64_t lost_samples;
u64 (*clock)(void);
perf_overflow_handler_t overflow_handler;
void *overflow_handler_context;

View File

@ -273,7 +273,6 @@ enum {
* { u64 time_enabled; } && PERF_FORMAT_TOTAL_TIME_ENABLED
* { u64 time_running; } && PERF_FORMAT_TOTAL_TIME_RUNNING
* { u64 id; } && PERF_FORMAT_ID
* { u64 lost; } && PERF_FORMAT_LOST
* } && !PERF_FORMAT_GROUP
*
* { u64 nr;
@ -281,7 +280,6 @@ enum {
* { u64 time_running; } && PERF_FORMAT_TOTAL_TIME_RUNNING
* { u64 value;
* { u64 id; } && PERF_FORMAT_ID
* { u64 lost; } && PERF_FORMAT_LOST
* } cntr[nr];
* } && PERF_FORMAT_GROUP
* };
@ -291,9 +289,8 @@ enum perf_event_read_format {
PERF_FORMAT_TOTAL_TIME_RUNNING = 1U << 1,
PERF_FORMAT_ID = 1U << 2,
PERF_FORMAT_GROUP = 1U << 3,
PERF_FORMAT_LOST = 1U << 4,
PERF_FORMAT_MAX = 1U << 5, /* non-ABI */
PERF_FORMAT_MAX = 1U << 4, /* non-ABI */
};
#define PERF_ATTR_SIZE_VER0 64 /* sizeof first published struct */

View File

@ -1726,9 +1726,6 @@ static void __perf_event_read_size(struct perf_event *event, int nr_siblings)
if (event->attr.read_format & PERF_FORMAT_ID)
entry += sizeof(u64);
if (event->attr.read_format & PERF_FORMAT_LOST)
entry += sizeof(u64);
if (event->attr.read_format & PERF_FORMAT_GROUP) {
nr += nr_siblings;
size += sizeof(u64);
@ -4892,15 +4889,11 @@ static int __perf_read_group_add(struct perf_event *leader,
values[n++] += perf_event_count(leader);
if (read_format & PERF_FORMAT_ID)
values[n++] = primary_event_id(leader);
if (read_format & PERF_FORMAT_LOST)
values[n++] = atomic64_read(&leader->lost_samples);
for_each_sibling_event(sub, leader) {
values[n++] += perf_event_count(sub);
if (read_format & PERF_FORMAT_ID)
values[n++] = primary_event_id(sub);
if (read_format & PERF_FORMAT_LOST)
values[n++] = atomic64_read(&sub->lost_samples);
}
raw_spin_unlock_irqrestore(&ctx->lock, flags);
@ -4957,7 +4950,7 @@ static int perf_read_one(struct perf_event *event,
u64 read_format, char __user *buf)
{
u64 enabled, running;
u64 values[5];
u64 values[4];
int n = 0;
values[n++] = __perf_event_read_value(event, &enabled, &running);
@ -4967,8 +4960,6 @@ static int perf_read_one(struct perf_event *event,
values[n++] = running;
if (read_format & PERF_FORMAT_ID)
values[n++] = primary_event_id(event);
if (read_format & PERF_FORMAT_LOST)
values[n++] = atomic64_read(&event->lost_samples);
if (copy_to_user(buf, values, n * sizeof(u64)))
return -EFAULT;
@ -6311,7 +6302,7 @@ static void perf_output_read_one(struct perf_output_handle *handle,
u64 enabled, u64 running)
{
u64 read_format = event->attr.read_format;
u64 values[5];
u64 values[4];
int n = 0;
values[n++] = perf_event_count(event);
@ -6325,8 +6316,6 @@ static void perf_output_read_one(struct perf_output_handle *handle,
}
if (read_format & PERF_FORMAT_ID)
values[n++] = primary_event_id(event);
if (read_format & PERF_FORMAT_LOST)
values[n++] = atomic64_read(&event->lost_samples);
__output_copy(handle, values, n * sizeof(u64));
}
@ -6337,7 +6326,7 @@ static void perf_output_read_group(struct perf_output_handle *handle,
{
struct perf_event *leader = event->group_leader, *sub;
u64 read_format = event->attr.read_format;
u64 values[6];
u64 values[5];
int n = 0;
values[n++] = 1 + leader->nr_siblings;
@ -6355,8 +6344,6 @@ static void perf_output_read_group(struct perf_output_handle *handle,
values[n++] = perf_event_count(leader);
if (read_format & PERF_FORMAT_ID)
values[n++] = primary_event_id(leader);
if (read_format & PERF_FORMAT_LOST)
values[n++] = atomic64_read(&leader->lost_samples);
__output_copy(handle, values, n * sizeof(u64));
@ -6370,8 +6357,6 @@ static void perf_output_read_group(struct perf_output_handle *handle,
values[n++] = perf_event_count(sub);
if (read_format & PERF_FORMAT_ID)
values[n++] = primary_event_id(sub);
if (read_format & PERF_FORMAT_LOST)
values[n++] = atomic64_read(&sub->lost_samples);
__output_copy(handle, values, n * sizeof(u64));
}

View File

@ -171,10 +171,8 @@ __perf_output_begin(struct perf_output_handle *handle,
goto out;
if (unlikely(rb->paused)) {
if (rb->nr_pages) {
if (rb->nr_pages)
local_inc(&rb->lost);
atomic64_inc(&event->lost_samples);
}
goto out;
}
@ -257,7 +255,6 @@ __perf_output_begin(struct perf_output_handle *handle,
fail:
local_inc(&rb->lost);
atomic64_inc(&event->lost_samples);
perf_output_put_handle(handle);
out:
rcu_read_unlock();