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perf: Remove more code from the fastpath

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Sanity checks cost instructions.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <20100521090710.852926930@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Peter Zijlstra 2010-05-20 19:50:07 +02:00 committed by Ingo Molnar
parent 3cafa9fbb5
commit a94ffaaf55
2 changed files with 4 additions and 18 deletions
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2
include/linux/perf_event.h
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@ -803,8 +803,6 @@ struct perf_cpu_context {
struct perf_output_handle { struct perf_output_handle {
struct perf_event *event; struct perf_event *event;
struct perf_mmap_data *data; struct perf_mmap_data *data;
unsigned long head;
unsigned long offset;
unsigned long wakeup; unsigned long wakeup;
unsigned long size; unsigned long size;
void *addr; void *addr;

20
kernel/perf_event.c
View File

@ -2967,20 +2967,11 @@ again:
preempt_enable(); preempt_enable();
} }
void perf_output_copy(struct perf_output_handle *handle, __always_inline void perf_output_copy(struct perf_output_handle *handle,
const void *buf, unsigned int len) const void *buf, unsigned int len)
{ {
handle->offset += len;
/*
* Check we didn't copy past our reservation window, taking the
* possible unsigned int wrap into account.
*/
if (WARN_ON_ONCE(((long)(handle->head - handle->offset)) < 0))
return;
do { do {
unsigned long size = min(handle->size, len); unsigned long size = min_t(unsigned long, handle->size, len);
memcpy(handle->addr, buf, size); memcpy(handle->addr, buf, size);
@ -3055,15 +3046,12 @@ int perf_output_begin(struct perf_output_handle *handle,
goto fail; goto fail;
} while (local_cmpxchg(&data->head, offset, head) != offset); } while (local_cmpxchg(&data->head, offset, head) != offset);
handle->offset = offset;
handle->head = head;
if (head - local_read(&data->wakeup) > data->watermark) if (head - local_read(&data->wakeup) > data->watermark)
local_add(data->watermark, &data->wakeup); local_add(data->watermark, &data->wakeup);
handle->page = handle->offset >> (PAGE_SHIFT + page_order(data)); handle->page = offset >> (PAGE_SHIFT + page_order(data));
handle->page &= data->nr_pages - 1; handle->page &= data->nr_pages - 1;
handle->size = handle->offset & ((PAGE_SIZE << page_order(data)) - 1); handle->size = offset & ((PAGE_SIZE << page_order(data)) - 1);
handle->addr = data->data_pages[handle->page]; handle->addr = data->data_pages[handle->page];
handle->addr += handle->size; handle->addr += handle->size;
handle->size = (PAGE_SIZE << page_order(data)) - handle->size; handle->size = (PAGE_SIZE << page_order(data)) - handle->size;