/* Linux-dependent part of branch trace support for GDB, and GDBserver.
- Copyright (C) 2013-2015 Free Software Foundation, Inc.
+ Copyright (C) 2013-2019 Free Software Foundation, Inc.
Contributed by Intel Corp. <markus.t.metzger@intel.com>
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
-#include "common-defs.h"
+#include "gdbsupport/common-defs.h"
#include "linux-btrace.h"
-#include "common-regcache.h"
-#include "gdb_wait.h"
+#include "gdbsupport/common-regcache.h"
+#include "gdbsupport/gdb_wait.h"
#include "x86-cpuid.h"
+#include "gdbsupport/filestuff.h"
+#include "gdbsupport/scoped_fd.h"
+#include "gdbsupport/scoped_mmap.h"
+
+#include <inttypes.h>
-#ifdef HAVE_SYS_SYSCALL_H
#include <sys/syscall.h>
-#endif
#if HAVE_LINUX_PERF_EVENT_H && defined(SYS_perf_event_open)
#include <unistd.h>
#include <sys/mman.h>
#include <sys/user.h>
-#include <sys/ptrace.h>
+#include "nat/gdb_ptrace.h"
#include <sys/types.h>
#include <signal.h>
-#include <sys/utsname.h>
/* A branch trace record in perf_event. */
struct perf_event_bts
return *pev->data_head != pev->last_head;
}
-/* Try to determine the size of a pointer in bits for the OS.
-
- This is the same as the size of a pointer for the inferior process
- except when a 32-bit inferior is running on a 64-bit OS. */
-
/* Copy the last SIZE bytes from PEV ending at DATA_HEAD and return a pointer
to the memory holding the copy.
The caller is responsible for freeing the memory. */
static gdb_byte *
-perf_event_read (const struct perf_event_buffer *pev, unsigned long data_head,
- unsigned long size)
+perf_event_read (const struct perf_event_buffer *pev, __u64 data_head,
+ size_t size)
{
const gdb_byte *begin, *end, *start, *stop;
gdb_byte *buffer;
- unsigned long data_tail, buffer_size;
+ size_t buffer_size;
+ __u64 data_tail;
if (size == 0)
return NULL;
+ /* We should never ask for more data than the buffer can hold. */
+ buffer_size = pev->size;
+ gdb_assert (size <= buffer_size);
+
+ /* If we ask for more data than we seem to have, we wrap around and read
+ data from the end of the buffer. This is already handled by the %
+ BUFFER_SIZE operation, below. Here, we just need to make sure that we
+ don't underflow.
+
+ Note that this is perfectly OK for perf event buffers where data_head
+ doesn'grow indefinitely and instead wraps around to remain within the
+ buffer's boundaries. */
+ if (data_head < size)
+ data_head += buffer_size;
+
gdb_assert (size <= data_head);
data_tail = data_head - size;
- buffer_size = pev->size;
begin = pev->mem;
start = begin + data_tail % buffer_size;
stop = begin + data_head % buffer_size;
- buffer = xmalloc (size);
+ buffer = (gdb_byte *) xmalloc (size);
if (start < stop)
memcpy (buffer, start, stop - start);
static void
perf_event_read_all (struct perf_event_buffer *pev, gdb_byte **data,
- unsigned long *psize)
+ size_t *psize)
{
- unsigned long data_head, size;
+ size_t size;
+ __u64 data_head;
data_head = *pev->data_head;
-
size = pev->size;
- if (data_head < size)
- size = data_head;
*data = perf_event_read (pev, data_head, size);
*psize = size;
pev->last_head = data_head;
}
-/* Determine the event type.
- Returns zero on success and fills in TYPE; returns -1 otherwise. */
+/* Try to determine the start address of the Linux kernel. */
-static int
-perf_event_pt_event_type (int *type)
+static uint64_t
+linux_determine_kernel_start (void)
{
- FILE *file;
- int found;
-
- file = fopen ("/sys/bus/event_source/devices/intel_pt/type", "r");
- if (file == NULL)
- return -1;
+ static uint64_t kernel_start;
+ static int cached;
- found = fscanf (file, "%d", type);
+ if (cached != 0)
+ return kernel_start;
- fclose (file);
+ cached = 1;
- if (found == 1)
- return 0;
- return -1;
-}
+ gdb_file_up file = gdb_fopen_cloexec ("/proc/kallsyms", "r");
+ if (file == NULL)
+ return kernel_start;
-static int
-linux_determine_kernel_ptr_bits (void)
-{
- struct utsname utsn;
- int errcode;
+ while (!feof (file.get ()))
+ {
+ char buffer[1024], symbol[8], *line;
+ uint64_t addr;
+ int match;
- memset (&utsn, 0, sizeof (utsn));
+ line = fgets (buffer, sizeof (buffer), file.get ());
+ if (line == NULL)
+ break;
- errcode = uname (&utsn);
- if (errcode < 0)
- return 0;
+ match = sscanf (line, "%" SCNx64 " %*[tT] %7s", &addr, symbol);
+ if (match != 2)
+ continue;
- /* We only need to handle the 64-bit host case, here. For 32-bit host,
- the pointer size can be filled in later based on the inferior. */
- if (strcmp (utsn.machine, "x86_64") == 0)
- return 64;
+ if (strcmp (symbol, "_text") == 0)
+ {
+ kernel_start = addr;
+ break;
+ }
+ }
- return 0;
+ return kernel_start;
}
/* Check whether an address is in the kernel. */
static inline int
-perf_event_is_kernel_addr (const struct btrace_target_info *tinfo,
- uint64_t addr)
+perf_event_is_kernel_addr (uint64_t addr)
{
- uint64_t mask;
-
- /* If we don't know the size of a pointer, we can't check. Let's assume it's
- not a kernel address in this case. */
- if (tinfo->ptr_bits == 0)
- return 0;
+ uint64_t kernel_start;
- /* A bit mask for the most significant bit in an address. */
- mask = (uint64_t) 1 << (tinfo->ptr_bits - 1);
+ kernel_start = linux_determine_kernel_start ();
+ if (kernel_start != 0ull)
+ return (addr >= kernel_start);
- /* Check whether the most significant bit in the address is set. */
- return (addr & mask) != 0;
+ /* If we don't know the kernel's start address, let's check the most
+ significant bit. This will work at least for 64-bit kernels. */
+ return ((addr & (1ull << 63)) != 0);
}
/* Check whether a perf event record should be skipped. */
static inline int
-perf_event_skip_bts_record (const struct btrace_target_info *tinfo,
- const struct perf_event_bts *bts)
+perf_event_skip_bts_record (const struct perf_event_bts *bts)
{
/* The hardware may report branches from kernel into user space. Branches
from user into kernel space will be suppressed. We filter the former to
provide a consistent branch trace excluding kernel. */
- return perf_event_is_kernel_addr (tinfo, bts->from);
+ return perf_event_is_kernel_addr (bts->from);
}
/* Perform a few consistency checks on a perf event sample record. This is
In case the buffer overflows during sampling, one sample may have its lower
part at the end and its upper part at the beginning of the buffer. */
-static VEC (btrace_block_s) *
+static std::vector <btrace_block> *
perf_event_read_bts (struct btrace_target_info* tinfo, const uint8_t *begin,
- const uint8_t *end, const uint8_t *start,
- unsigned long long size)
+ const uint8_t *end, const uint8_t *start, size_t size)
{
- VEC (btrace_block_s) *btrace = NULL;
+ std::vector <btrace_block> *btrace = new std::vector <btrace_block>;
struct perf_event_sample sample;
- unsigned long long read = 0;
+ size_t read = 0;
struct btrace_block block = { 0, 0 };
struct regcache *regcache;
break;
}
- if (perf_event_skip_bts_record (tinfo, &psample->bts))
+ if (perf_event_skip_bts_record (&psample->bts))
continue;
/* We found a valid sample, so we can complete the current block. */
block.begin = psample->bts.to;
- VEC_safe_push (btrace_block_s, btrace, &block);
+ btrace->push_back (block);
/* Start the next block. */
block.end = psample->bts.from;
reading delta trace, we can fill in the start address later on.
Otherwise we will prune it. */
block.begin = 0;
- VEC_safe_push (btrace_block_s, btrace, &block);
+ btrace->push_back (block);
return btrace;
}
-/* Check whether the kernel supports BTS. */
-
-static int
-kernel_supports_bts (void)
-{
- struct perf_event_attr attr;
- pid_t child, pid;
- int status, file;
-
- errno = 0;
- child = fork ();
- switch (child)
- {
- case -1:
- warning (_("test bts: cannot fork: %s."), strerror (errno));
- return 0;
-
- case 0:
- status = ptrace (PTRACE_TRACEME, 0, NULL, NULL);
- if (status != 0)
- {
- warning (_("test bts: cannot PTRACE_TRACEME: %s."),
- strerror (errno));
- _exit (1);
- }
-
- status = raise (SIGTRAP);
- if (status != 0)
- {
- warning (_("test bts: cannot raise SIGTRAP: %s."),
- strerror (errno));
- _exit (1);
- }
-
- _exit (1);
-
- default:
- pid = waitpid (child, &status, 0);
- if (pid != child)
- {
- warning (_("test bts: bad pid %ld, error: %s."),
- (long) pid, strerror (errno));
- return 0;
- }
-
- if (!WIFSTOPPED (status))
- {
- warning (_("test bts: expected stop. status: %d."),
- status);
- return 0;
- }
-
- memset (&attr, 0, sizeof (attr));
-
- attr.type = PERF_TYPE_HARDWARE;
- attr.config = PERF_COUNT_HW_BRANCH_INSTRUCTIONS;
- attr.sample_period = 1;
- attr.sample_type = PERF_SAMPLE_IP | PERF_SAMPLE_ADDR;
- attr.exclude_kernel = 1;
- attr.exclude_hv = 1;
- attr.exclude_idle = 1;
-
- file = syscall (SYS_perf_event_open, &attr, child, -1, -1, 0);
- if (file >= 0)
- close (file);
-
- kill (child, SIGKILL);
- ptrace (PTRACE_KILL, child, NULL, NULL);
-
- pid = waitpid (child, &status, 0);
- if (pid != child)
- {
- warning (_("test bts: bad pid %ld, error: %s."),
- (long) pid, strerror (errno));
- if (!WIFSIGNALED (status))
- warning (_("test bts: expected killed. status: %d."),
- status);
- }
-
- return (file >= 0);
- }
-}
-
-/* Check whether the kernel supports Intel(R) Processor Trace. */
-
-static int
-kernel_supports_pt (void)
-{
- struct perf_event_attr attr;
- pid_t child, pid;
- int status, file, type;
-
- errno = 0;
- child = fork ();
- switch (child)
- {
- case -1:
- warning (_("test pt: cannot fork: %s."), strerror (errno));
- return 0;
-
- case 0:
- status = ptrace (PTRACE_TRACEME, 0, NULL, NULL);
- if (status != 0)
- {
- warning (_("test pt: cannot PTRACE_TRACEME: %s."),
- strerror (errno));
- _exit (1);
- }
-
- status = raise (SIGTRAP);
- if (status != 0)
- {
- warning (_("test pt: cannot raise SIGTRAP: %s."),
- strerror (errno));
- _exit (1);
- }
-
- _exit (1);
-
- default:
- pid = waitpid (child, &status, 0);
- if (pid != child)
- {
- warning (_("test pt: bad pid %ld, error: %s."),
- (long) pid, strerror (errno));
- return 0;
- }
-
- if (!WIFSTOPPED (status))
- {
- warning (_("test pt: expected stop. status: %d."),
- status);
- return 0;
- }
-
- status = perf_event_pt_event_type (&type);
- if (status != 0)
- file = -1;
- else
- {
- memset (&attr, 0, sizeof (attr));
-
- attr.size = sizeof (attr);
- attr.type = type;
- attr.exclude_kernel = 1;
- attr.exclude_hv = 1;
- attr.exclude_idle = 1;
-
- file = syscall (SYS_perf_event_open, &attr, child, -1, -1, 0);
- if (file >= 0)
- close (file);
- }
-
- kill (child, SIGKILL);
- ptrace (PTRACE_KILL, child, NULL, NULL);
-
- pid = waitpid (child, &status, 0);
- if (pid != child)
- {
- warning (_("test pt: bad pid %ld, error: %s."),
- (long) pid, strerror (errno));
- if (!WIFSIGNALED (status))
- warning (_("test pt: expected killed. status: %d."),
- status);
- }
-
- return (file >= 0);
- }
-}
-
/* Check whether an Intel cpu supports BTS. */
static int
}
}
-/* Check whether the linux target supports BTS. */
-
-static int
-linux_supports_bts (void)
-{
- static int cached;
-
- if (cached == 0)
- {
- if (!kernel_supports_bts ())
- cached = -1;
- else if (!cpu_supports_bts ())
- cached = -1;
- else
- cached = 1;
- }
-
- return cached > 0;
-}
-
-/* Check whether the linux target supports Intel(R) Processor Trace. */
-
-static int
-linux_supports_pt (void)
-{
- static int cached;
-
- if (cached == 0)
- {
- if (!kernel_supports_pt ())
- cached = -1;
- else
- cached = 1;
- }
-
- return cached > 0;
-}
-
-/* See linux-btrace.h. */
+/* The perf_event_open syscall failed. Try to print a helpful error
+ message. */
-int
-linux_supports_btrace (struct target_ops *ops, enum btrace_format format)
+static void
+diagnose_perf_event_open_fail ()
{
- switch (format)
+ switch (errno)
{
- case BTRACE_FORMAT_NONE:
- return 0;
+ case EPERM:
+ case EACCES:
+ {
+ static const char filename[] = "/proc/sys/kernel/perf_event_paranoid";
+ gdb_file_up file = gdb_fopen_cloexec (filename, "r");
+ if (file.get () == nullptr)
+ break;
- case BTRACE_FORMAT_BTS:
- return linux_supports_bts ();
+ int level, found = fscanf (file.get (), "%d", &level);
+ if (found == 1 && level > 2)
+ error (_("You do not have permission to record the process. "
+ "Try setting %s to 2 or less."), filename);
+ }
- case BTRACE_FORMAT_PT:
- return linux_supports_pt ();
+ break;
}
- internal_error (__FILE__, __LINE__, _("Unknown branch trace format"));
+ error (_("Failed to start recording: %s"), safe_strerror (errno));
}
/* Enable branch tracing in BTS format. */
static struct btrace_target_info *
linux_enable_bts (ptid_t ptid, const struct btrace_config_bts *conf)
{
- struct perf_event_mmap_page *header;
- struct btrace_target_info *tinfo;
struct btrace_tinfo_bts *bts;
- unsigned long long size, pages;
+ size_t size, pages;
+ __u64 data_offset;
int pid, pg;
- tinfo = xzalloc (sizeof (*tinfo));
+ if (!cpu_supports_bts ())
+ error (_("BTS support has been disabled for the target cpu."));
+
+ gdb::unique_xmalloc_ptr<btrace_target_info> tinfo
+ (XCNEW (btrace_target_info));
tinfo->ptid = ptid;
- tinfo->ptr_bits = linux_determine_kernel_ptr_bits ();
tinfo->conf.format = BTRACE_FORMAT_BTS;
bts = &tinfo->variant.bts;
bts->attr.exclude_hv = 1;
bts->attr.exclude_idle = 1;
- pid = ptid_get_lwp (ptid);
+ pid = ptid.lwp ();
if (pid == 0)
- pid = ptid_get_pid (ptid);
+ pid = ptid.pid ();
errno = 0;
- bts->file = syscall (SYS_perf_event_open, &bts->attr, pid, -1, -1, 0);
- if (bts->file < 0)
- goto err_out;
+ scoped_fd fd (syscall (SYS_perf_event_open, &bts->attr, pid, -1, -1, 0));
+ if (fd.get () < 0)
+ diagnose_perf_event_open_fail ();
/* Convert the requested size in bytes to pages (rounding up). */
- pages = (((unsigned long long) conf->size) + PAGE_SIZE - 1) / PAGE_SIZE;
+ pages = ((size_t) conf->size / PAGE_SIZE
+ + ((conf->size % PAGE_SIZE) == 0 ? 0 : 1));
/* We need at least one page. */
if (pages == 0)
pages = 1;
/* The buffer size can be requested in powers of two pages. Adjust PAGES
to the next power of two. */
- for (pg = 0; pages != (1u << pg); ++pg)
- if ((pages & (1u << pg)) != 0)
- pages += (1u << pg);
+ for (pg = 0; pages != ((size_t) 1 << pg); ++pg)
+ if ((pages & ((size_t) 1 << pg)) != 0)
+ pages += ((size_t) 1 << pg);
/* We try to allocate the requested size.
If that fails, try to get as much as we can. */
+ scoped_mmap data;
for (; pages > 0; pages >>= 1)
{
size_t length;
+ __u64 data_size;
+
+ data_size = (__u64) pages * PAGE_SIZE;
- size = pages * PAGE_SIZE;
+ /* Don't ask for more than we can represent in the configuration. */
+ if ((__u64) UINT_MAX < data_size)
+ continue;
+
+ size = (size_t) data_size;
length = size + PAGE_SIZE;
/* Check for overflows. */
- if ((unsigned long long) length < size)
+ if ((__u64) length != data_size + PAGE_SIZE)
continue;
+ errno = 0;
/* The number of pages we request needs to be a power of two. */
- header = mmap (NULL, length, PROT_READ, MAP_SHARED, bts->file, 0);
- if (header != MAP_FAILED)
+ data.reset (nullptr, length, PROT_READ, MAP_SHARED, fd.get (), 0);
+ if (data.get () != MAP_FAILED)
break;
}
- if (header == MAP_FAILED)
- goto err_file;
+ if (pages == 0)
+ error (_("Failed to map trace buffer: %s."), safe_strerror (errno));
- bts->header = header;
- bts->bts.mem = ((const uint8_t *) header) + PAGE_SIZE;
- bts->bts.size = size;
- bts->bts.data_head = &header->data_head;
- bts->bts.last_head = 0;
+ struct perf_event_mmap_page *header = (struct perf_event_mmap_page *)
+ data.get ();
+ data_offset = PAGE_SIZE;
+
+#if defined (PERF_ATTR_SIZE_VER5)
+ if (offsetof (struct perf_event_mmap_page, data_size) <= header->size)
+ {
+ __u64 data_size;
- tinfo->conf.bts.size = size;
- return tinfo;
+ data_offset = header->data_offset;
+ data_size = header->data_size;
- err_file:
- /* We were not able to allocate any buffer. */
- close (bts->file);
+ size = (unsigned int) data_size;
- err_out:
- xfree (tinfo);
- return NULL;
+ /* Check for overflows. */
+ if ((__u64) size != data_size)
+ error (_("Failed to determine trace buffer size."));
+ }
+#endif /* defined (PERF_ATTR_SIZE_VER5) */
+
+ bts->bts.size = size;
+ bts->bts.data_head = &header->data_head;
+ bts->bts.mem = (const uint8_t *) data.release () + data_offset;
+ bts->bts.last_head = 0ull;
+ bts->header = header;
+ bts->file = fd.release ();
+
+ tinfo->conf.bts.size = (unsigned int) size;
+ return tinfo.release ();
}
#if defined (PERF_ATTR_SIZE_VER5)
-/* Enable branch tracing in Intel(R) Processor Trace format. */
+/* Determine the event type. */
+
+static int
+perf_event_pt_event_type ()
+{
+ static const char filename[] = "/sys/bus/event_source/devices/intel_pt/type";
+
+ errno = 0;
+ gdb_file_up file = gdb_fopen_cloexec (filename, "r");
+ if (file.get () == nullptr)
+ error (_("Failed to open %s: %s."), filename, safe_strerror (errno));
+
+ int type, found = fscanf (file.get (), "%d", &type);
+ if (found != 1)
+ error (_("Failed to read the PT event type from %s."), filename);
+
+ return type;
+}
+
+/* Enable branch tracing in Intel Processor Trace format. */
static struct btrace_target_info *
linux_enable_pt (ptid_t ptid, const struct btrace_config_pt *conf)
{
- struct perf_event_mmap_page *header;
- struct btrace_target_info *tinfo;
struct btrace_tinfo_pt *pt;
- unsigned long long pages, size;
- int pid, pg, errcode, type;
-
- if (conf->size == 0)
- return NULL;
-
- errcode = perf_event_pt_event_type (&type);
- if (errcode != 0)
- return NULL;
+ size_t pages;
+ int pid, pg;
- pid = ptid_get_lwp (ptid);
+ pid = ptid.lwp ();
if (pid == 0)
- pid = ptid_get_pid (ptid);
+ pid = ptid.pid ();
- tinfo = xzalloc (sizeof (*tinfo));
+ gdb::unique_xmalloc_ptr<btrace_target_info> tinfo
+ (XCNEW (btrace_target_info));
tinfo->ptid = ptid;
- tinfo->ptr_bits = 0;
tinfo->conf.format = BTRACE_FORMAT_PT;
pt = &tinfo->variant.pt;
pt->attr.size = sizeof (pt->attr);
- pt->attr.type = type;
+ pt->attr.type = perf_event_pt_event_type ();
pt->attr.exclude_kernel = 1;
pt->attr.exclude_hv = 1;
pt->attr.exclude_idle = 1;
errno = 0;
- pt->file = syscall (SYS_perf_event_open, &pt->attr, pid, -1, -1, 0);
- if (pt->file < 0)
- goto err;
+ scoped_fd fd (syscall (SYS_perf_event_open, &pt->attr, pid, -1, -1, 0));
+ if (fd.get () < 0)
+ diagnose_perf_event_open_fail ();
/* Allocate the configuration page. */
- header = mmap (NULL, PAGE_SIZE, PROT_READ | PROT_WRITE, MAP_SHARED,
- pt->file, 0);
- if (header == MAP_FAILED)
- goto err_file;
+ scoped_mmap data (nullptr, PAGE_SIZE, PROT_READ | PROT_WRITE, MAP_SHARED,
+ fd.get (), 0);
+ if (data.get () == MAP_FAILED)
+ error (_("Failed to map trace user page: %s."), safe_strerror (errno));
+
+ struct perf_event_mmap_page *header = (struct perf_event_mmap_page *)
+ data.get ();
header->aux_offset = header->data_offset + header->data_size;
/* Convert the requested size in bytes to pages (rounding up). */
- pages = (((unsigned long long) conf->size) + PAGE_SIZE - 1) / PAGE_SIZE;
+ pages = ((size_t) conf->size / PAGE_SIZE
+ + ((conf->size % PAGE_SIZE) == 0 ? 0 : 1));
/* We need at least one page. */
if (pages == 0)
pages = 1;
/* The buffer size can be requested in powers of two pages. Adjust PAGES
to the next power of two. */
- for (pg = 0; pages != (1u << pg); ++pg)
- if ((pages & (1u << pg)) != 0)
- pages += (1u << pg);
+ for (pg = 0; pages != ((size_t) 1 << pg); ++pg)
+ if ((pages & ((size_t) 1 << pg)) != 0)
+ pages += ((size_t) 1 << pg);
/* We try to allocate the requested size.
If that fails, try to get as much as we can. */
+ scoped_mmap aux;
for (; pages > 0; pages >>= 1)
{
size_t length;
+ __u64 data_size;
+
+ data_size = (__u64) pages * PAGE_SIZE;
+
+ /* Don't ask for more than we can represent in the configuration. */
+ if ((__u64) UINT_MAX < data_size)
+ continue;
- size = pages * PAGE_SIZE;
- length = size;
+ length = (size_t) data_size;
/* Check for overflows. */
- if ((unsigned long long) length < size)
+ if ((__u64) length != data_size)
continue;
- header->aux_size = size;
+ header->aux_size = data_size;
- pt->pt.mem = mmap (NULL, length, PROT_READ, MAP_SHARED, pt->file,
- header->aux_offset);
- if (pt->pt.mem != MAP_FAILED)
+ errno = 0;
+ aux.reset (nullptr, length, PROT_READ, MAP_SHARED, fd.get (),
+ header->aux_offset);
+ if (aux.get () != MAP_FAILED)
break;
}
if (pages == 0)
- goto err_conf;
+ error (_("Failed to map trace buffer: %s."), safe_strerror (errno));
- pt->header = header;
- pt->pt.size = size;
+ pt->pt.size = aux.size ();
+ pt->pt.mem = (const uint8_t *) aux.release ();
pt->pt.data_head = &header->aux_head;
+ pt->header = (struct perf_event_mmap_page *) data.release ();
+ gdb_assert (pt->header == header);
+ pt->file = fd.release ();
- tinfo->conf.pt.size = size;
- return tinfo;
-
- err_conf:
- munmap((void *) header, PAGE_SIZE);
-
- err_file:
- close (pt->file);
-
- err:
- xfree (tinfo);
- return NULL;
+ tinfo->conf.pt.size = (unsigned int) pt->pt.size;
+ return tinfo.release ();
}
#else /* !defined (PERF_ATTR_SIZE_VER5) */
static struct btrace_target_info *
linux_enable_pt (ptid_t ptid, const struct btrace_config_pt *conf)
{
- errno = EOPNOTSUPP;
- return NULL;
+ error (_("Intel Processor Trace support was disabled at compile time."));
}
#endif /* !defined (PERF_ATTR_SIZE_VER5) */
struct btrace_target_info *
linux_enable_btrace (ptid_t ptid, const struct btrace_config *conf)
{
- struct btrace_target_info *tinfo;
-
- tinfo = NULL;
switch (conf->format)
{
case BTRACE_FORMAT_NONE:
- break;
+ error (_("Bad branch trace format."));
+
+ default:
+ error (_("Unknown branch trace format."));
case BTRACE_FORMAT_BTS:
- tinfo = linux_enable_bts (ptid, &conf->bts);
- break;
+ return linux_enable_bts (ptid, &conf->bts);
case BTRACE_FORMAT_PT:
- tinfo = linux_enable_pt (ptid, &conf->pt);
- break;
+ return linux_enable_pt (ptid, &conf->pt);
}
-
- return tinfo;
}
/* Disable BTS tracing. */
return BTRACE_ERR_NONE;
}
-/* Disable Intel(R) Processor Trace tracing. */
+/* Disable Intel Processor Trace tracing. */
static enum btrace_error
linux_disable_pt (struct btrace_tinfo_pt *tinfo)
{
struct perf_event_buffer *pevent;
const uint8_t *begin, *end, *start;
- unsigned long long data_head, data_tail, buffer_size, size;
+ size_t buffer_size, size;
+ __u64 data_head, data_tail;
unsigned int retries = 5;
pevent = &tinfo->variant.bts.bts;
data_head = *pevent->data_head;
/* Delete any leftover trace from the previous iteration. */
- VEC_free (btrace_block_s, btrace->blocks);
+ delete btrace->blocks;
+ btrace->blocks = nullptr;
if (type == BTRACE_READ_DELTA)
{
+ __u64 data_size;
+
/* Determine the number of bytes to read and check for buffer
overflows. */
return BTRACE_ERR_OVERFLOW;
/* If the buffer is smaller than the trace delta, we overflowed. */
- size = data_head - data_tail;
- if (buffer_size < size)
+ data_size = data_head - data_tail;
+ if (buffer_size < data_size)
return BTRACE_ERR_OVERFLOW;
+
+ /* DATA_SIZE <= BUFFER_SIZE and therefore fits into a size_t. */
+ size = (size_t) data_size;
}
else
{
/* Adjust the size if the buffer has not overflowed, yet. */
if (data_head < size)
- size = data_head;
+ size = (size_t) data_head;
}
/* Data_head keeps growing; the buffer itself is circular. */
/* Prune the incomplete last block (i.e. the first one of inferior execution)
if we're not doing a delta read. There is no way of filling in its zeroed
BEGIN element. */
- if (!VEC_empty (btrace_block_s, btrace->blocks)
- && type != BTRACE_READ_DELTA)
- VEC_pop (btrace_block_s, btrace->blocks);
+ if (!btrace->blocks->empty () && type != BTRACE_READ_DELTA)
+ btrace->blocks->pop_back ();
return BTRACE_ERR_NONE;
}
-/* Fill in the Intel(R) Processor Trace configuration information. */
+/* Fill in the Intel Processor Trace configuration information. */
static void
linux_fill_btrace_pt_config (struct btrace_data_pt_config *conf)
conf->cpu = btrace_this_cpu ();
}
-/* Read branch trace data in Intel(R) Processor Trace format for the thread
+/* Read branch trace data in Intel Processor Trace format for the thread
given by TINFO into BTRACE using the TYPE reading method. */
static enum btrace_error
return linux_read_bts (&btrace->variant.bts, tinfo, type);
case BTRACE_FORMAT_PT:
- /* We read btrace in Intel(R) Processor Trace format. */
+ /* We read btrace in Intel Processor Trace format. */
btrace->format = BTRACE_FORMAT_PT;
btrace->variant.pt.data = NULL;
btrace->variant.pt.size = 0;
/* See linux-btrace.h. */
-int
-linux_supports_btrace (struct target_ops *ops, enum btrace_format format)
-{
- return 0;
-}
-
-/* See linux-btrace.h. */
-
struct btrace_target_info *
linux_enable_btrace (ptid_t ptid, const struct btrace_config *conf)
{