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From FEDORA_PATCHES Mon Sep 17 00:00:00 2001
From: Fedora GDB patches <invalid@email.com>
Date: Fri, 27 Oct 2017 21:07:50 +0200
Subject: gdb-linux_perf-bundle.patch
;; [dts+el7] [x86*] Bundle linux_perf.h for libipt (RH BZ 1256513).
;;=fedora
diff --git a/gdb/gdb.c b/gdb/gdb.c
--- a/gdb/gdb.c
+++ b/gdb/gdb.c
@@ -21,6 +21,10 @@
#include "interps.h"
#include "run-on-main-thread.h"
+#ifdef PERF_ATTR_SIZE_VER5_BUNDLE
+extern "C" void __libipt_init(void);
+#endif
+
int
main (int argc, char **argv)
{
@@ -32,6 +36,10 @@ main (int argc, char **argv)
struct captured_main_args args;
+#ifdef PERF_ATTR_SIZE_VER5_BUNDLE
+ __libipt_init();
+#endif
+
memset (&args, 0, sizeof args);
args.argc = argc;
args.argv = argv;
diff --git a/gdb/nat/linux-btrace.h b/gdb/nat/linux-btrace.h
--- a/gdb/nat/linux-btrace.h
+++ b/gdb/nat/linux-btrace.h
@@ -28,6 +28,177 @@
# include <linux/perf_event.h>
#endif
+#ifdef PERF_ATTR_SIZE_VER5_BUNDLE
+#ifndef HAVE_LINUX_PERF_EVENT_H
+# error "PERF_ATTR_SIZE_VER5_BUNDLE && !HAVE_LINUX_PERF_EVENT_H"
+#endif
+#ifndef PERF_ATTR_SIZE_VER5
+#define PERF_ATTR_SIZE_VER5
+#define perf_event_mmap_page perf_event_mmap_page_bundle
+// kernel-headers-3.10.0-493.el7.x86_64/usr/include/linux/perf_event.h
+/*
+ * Structure of the page that can be mapped via mmap
+ */
+struct perf_event_mmap_page {
+ __u32 version; /* version number of this structure */
+ __u32 compat_version; /* lowest version this is compat with */
+
+ /*
+ * Bits needed to read the hw events in user-space.
+ *
+ * u32 seq, time_mult, time_shift, index, width;
+ * u64 count, enabled, running;
+ * u64 cyc, time_offset;
+ * s64 pmc = 0;
+ *
+ * do {
+ * seq = pc->lock;
+ * barrier()
+ *
+ * enabled = pc->time_enabled;
+ * running = pc->time_running;
+ *
+ * if (pc->cap_usr_time && enabled != running) {
+ * cyc = rdtsc();
+ * time_offset = pc->time_offset;
+ * time_mult = pc->time_mult;
+ * time_shift = pc->time_shift;
+ * }
+ *
+ * index = pc->index;
+ * count = pc->offset;
+ * if (pc->cap_user_rdpmc && index) {
+ * width = pc->pmc_width;
+ * pmc = rdpmc(index - 1);
+ * }
+ *
+ * barrier();
+ * } while (pc->lock != seq);
+ *
+ * NOTE: for obvious reason this only works on self-monitoring
+ * processes.
+ */
+ __u32 lock; /* seqlock for synchronization */
+ __u32 index; /* hardware event identifier */
+ __s64 offset; /* add to hardware event value */
+ __u64 time_enabled; /* time event active */
+ __u64 time_running; /* time event on cpu */
+ union {
+ __u64 capabilities;
+ struct {
+ __u64 cap_bit0 : 1, /* Always 0, deprecated, see commit 860f085b74e9 */
+ cap_bit0_is_deprecated : 1, /* Always 1, signals that bit 0 is zero */
+
+ cap_user_rdpmc : 1, /* The RDPMC instruction can be used to read counts */
+ cap_user_time : 1, /* The time_* fields are used */
+ cap_user_time_zero : 1, /* The time_zero field is used */
+ cap_____res : 59;
+ };
+ };
+
+ /*
+ * If cap_user_rdpmc this field provides the bit-width of the value
+ * read using the rdpmc() or equivalent instruction. This can be used
+ * to sign extend the result like:
+ *
+ * pmc <<= 64 - width;
+ * pmc >>= 64 - width; // signed shift right
+ * count += pmc;
+ */
+ __u16 pmc_width;
+
+ /*
+ * If cap_usr_time the below fields can be used to compute the time
+ * delta since time_enabled (in ns) using rdtsc or similar.
+ *
+ * u64 quot, rem;
+ * u64 delta;
+ *
+ * quot = (cyc >> time_shift);
+ * rem = cyc & (((u64)1 << time_shift) - 1);
+ * delta = time_offset + quot * time_mult +
+ * ((rem * time_mult) >> time_shift);
+ *
+ * Where time_offset,time_mult,time_shift and cyc are read in the
+ * seqcount loop described above. This delta can then be added to
+ * enabled and possible running (if index), improving the scaling:
+ *
+ * enabled += delta;
+ * if (index)
+ * running += delta;
+ *
+ * quot = count / running;
+ * rem = count % running;
+ * count = quot * enabled + (rem * enabled) / running;
+ */
+ __u16 time_shift;
+ __u32 time_mult;
+ __u64 time_offset;
+ /*
+ * If cap_usr_time_zero, the hardware clock (e.g. TSC) can be calculated
+ * from sample timestamps.
+ *
+ * time = timestamp - time_zero;
+ * quot = time / time_mult;
+ * rem = time % time_mult;
+ * cyc = (quot << time_shift) + (rem << time_shift) / time_mult;
+ *
+ * And vice versa:
+ *
+ * quot = cyc >> time_shift;
+ * rem = cyc & (((u64)1 << time_shift) - 1);
+ * timestamp = time_zero + quot * time_mult +
+ * ((rem * time_mult) >> time_shift);
+ */
+ __u64 time_zero;
+ __u32 size; /* Header size up to __reserved[] fields. */
+
+ /*
+ * Hole for extension of the self monitor capabilities
+ */
+
+ __u8 __reserved[118*8+4]; /* align to 1k. */
+
+ /*
+ * Control data for the mmap() data buffer.
+ *
+ * User-space reading the @data_head value should issue an smp_rmb(),
+ * after reading this value.
+ *
+ * When the mapping is PROT_WRITE the @data_tail value should be
+ * written by userspace to reflect the last read data, after issueing
+ * an smp_mb() to separate the data read from the ->data_tail store.
+ * In this case the kernel will not over-write unread data.
+ *
+ * See perf_output_put_handle() for the data ordering.
+ *
+ * data_{offset,size} indicate the location and size of the perf record
+ * buffer within the mmapped area.
+ */
+ __u64 data_head; /* head in the data section */
+ __u64 data_tail; /* user-space written tail */
+ __u64 data_offset; /* where the buffer starts */
+ __u64 data_size; /* data buffer size */
+
+ /*
+ * AUX area is defined by aux_{offset,size} fields that should be set
+ * by the userspace, so that
+ *
+ * aux_offset >= data_offset + data_size
+ *
+ * prior to mmap()ing it. Size of the mmap()ed area should be aux_size.
+ *
+ * Ring buffer pointers aux_{head,tail} have the same semantics as
+ * data_{head,tail} and same ordering rules apply.
+ */
+ __u64 aux_head;
+ __u64 aux_tail;
+ __u64 aux_offset;
+ __u64 aux_size;
+};
+#endif // PERF_ATTR_SIZE_VER5
+#endif // PERF_ATTR_SIZE_VER5_BUNDLE
+
struct target_ops;
#if HAVE_LINUX_PERF_EVENT_H
diff --git a/gdbsupport/common.m4 b/gdbsupport/common.m4
--- a/gdbsupport/common.m4
+++ b/gdbsupport/common.m4
@@ -168,7 +168,7 @@ AC_DEFUN([GDB_AC_COMMON], [
AC_PREPROC_IFELSE([AC_LANG_SOURCE([[
#include <linux/perf_event.h>
#ifndef PERF_ATTR_SIZE_VER5
- # error
+ // error // PERF_ATTR_SIZE_VER5_BUNDLE is not available here - Fedora+RHEL
#endif
]])], [perf_event=yes], [perf_event=no])
if test "$perf_event" != yes; then
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