From: Stephane Eranian <[email protected]>

When studying code layout, it is useful to capture the page size of the
sampled code address.

Add a new sample type for code page size.
The new sample type requires collecting the ip. The code page size can
be calculated from the IRQ-safe perf_get_page_size().

Only the generic support is covered. The large PEBS will be disabled
with this sample type.

Signed-off-by: Stephane Eranian <[email protected]>
Signed-off-by: Kan Liang <[email protected]>
---
 include/linux/perf_event.h      |  1 +
 include/uapi/linux/perf_event.h |  4 +++-
 kernel/events/core.c            | 11 ++++++++++-
 3 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index 3f94d0a..3551e20 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -939,6 +939,7 @@ struct perf_sample_data {
 
        u64                             phys_addr;
        u64                             data_page_size;
+       u64                             code_page_size;
 } ____cacheline_aligned;
 
 /* default value for data source */
diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h
index 513c8ae..dc29149 100644
--- a/include/uapi/linux/perf_event.h
+++ b/include/uapi/linux/perf_event.h
@@ -142,8 +142,9 @@ enum perf_event_sample_format {
        PERF_SAMPLE_REGS_INTR                   = 1U << 18,
        PERF_SAMPLE_PHYS_ADDR                   = 1U << 19,
        PERF_SAMPLE_DATA_PAGE_SIZE              = 1U << 20,
+       PERF_SAMPLE_CODE_PAGE_SIZE              = 1U << 21,
 
-       PERF_SAMPLE_MAX = 1U << 21,             /* non-ABI */
+       PERF_SAMPLE_MAX = 1U << 22,             /* non-ABI */
 
        __PERF_SAMPLE_CALLCHAIN_EARLY           = 1ULL << 63, /* non-ABI; 
internal use */
 };
@@ -863,6 +864,7 @@ enum perf_event_type {
         *        u64                   regs[weight(mask)]; } && 
PERF_SAMPLE_REGS_INTR
         *      { u64                   phys_addr;} && PERF_SAMPLE_PHYS_ADDR
         *      { u64                   data_page_size;} && 
PERF_SAMPLE_DATA_PAGE_SIZE
+        *      { u64                   code_page_size;} && 
PERF_SAMPLE_CODE_PAGE_SIZE
         * };
         */
        PERF_RECORD_SAMPLE                      = 9,
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 0ddb9c2..35871cd 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -1754,6 +1754,9 @@ static void __perf_event_header_size(struct perf_event 
*event, u64 sample_type)
        if (sample_type & PERF_SAMPLE_DATA_PAGE_SIZE)
                size += sizeof(data->data_page_size);
 
+       if (sample_type & PERF_SAMPLE_CODE_PAGE_SIZE)
+               size += sizeof(data->code_page_size);
+
        event->header_size = size;
 }
 
@@ -6305,6 +6308,9 @@ void perf_output_sample(struct perf_output_handle *handle,
        if (sample_type & PERF_SAMPLE_DATA_PAGE_SIZE)
                perf_output_put(handle, data->data_page_size);
 
+       if (sample_type & PERF_SAMPLE_CODE_PAGE_SIZE)
+               perf_output_put(handle, data->code_page_size);
+
        if (!event->attr.watermark) {
                int wakeup_events = event->attr.wakeup_events;
 
@@ -6393,7 +6399,7 @@ void perf_prepare_sample(struct perf_event_header *header,
 
        __perf_event_header__init_id(header, data, event);
 
-       if (sample_type & PERF_SAMPLE_IP)
+       if (sample_type & (PERF_SAMPLE_IP | PERF_SAMPLE_CODE_PAGE_SIZE))
                data->ip = perf_instruction_pointer(regs);
 
        if (sample_type & PERF_SAMPLE_CALLCHAIN) {
@@ -6502,6 +6508,9 @@ void perf_prepare_sample(struct perf_event_header *header,
 
        if (sample_type & PERF_SAMPLE_DATA_PAGE_SIZE)
                data->data_page_size = perf_get_page_size(data->addr);
+
+       if (sample_type & PERF_SAMPLE_CODE_PAGE_SIZE)
+               data->code_page_size = perf_get_page_size(data->ip);
 }
 
 static __always_inline void
-- 
2.7.4

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