diff options
| -rw-r--r-- | gdb/ChangeLog | 15 | ||||
| -rw-r--r-- | gdb/gdbserver/ChangeLog | 6 | ||||
| -rw-r--r-- | gdb/gdbserver/linux-low.c | 22 | ||||
| -rw-r--r-- | gdb/nat/linux-btrace.c | 83 | ||||
| -rw-r--r-- | gdb/nat/linux-btrace.h | 5 | ||||
| -rw-r--r-- | gdb/x86-linux-nat.c | 6 |
6 files changed, 73 insertions, 64 deletions
diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 8fca48e..bed048a 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,18 @@ +2015-09-09 Markus Metzger <markus.t.metzger@intel.com> + + * nat/linux-btrace.h (struct btrace_target_info) <ptr_bits>: Remove. + * nat/linux-btrace.c: Include filestuff.h and inttypes.h. + Remove include of sys/utsname.h. + (linux_determine_kernel_ptr_bits): Remove. + (linux_determine_kernel_start): New. + (perf_event_is_kernel_addr): Remove tinfo argument. Update users. + Update check. + (perf_event_skip_bts_record): Remove tinfo argument. Update users. + (linux_enable_bts, linux_enable_pt): Remove tinfo->ptr_bits + initialization. + * x86-linux-nat.c (x86_linux_enable_btrace): Remove ptr_bits + assignment. + 2015-09-07 Pedro Alves <palves@redhat.com> * guile/guile-internal.h (as_a_scm_t_subr): New. diff --git a/gdb/gdbserver/ChangeLog b/gdb/gdbserver/ChangeLog index 58a46b7..c6e9e34 100644 --- a/gdb/gdbserver/ChangeLog +++ b/gdb/gdbserver/ChangeLog @@ -1,3 +1,9 @@ +2015-09-09 Markus Metzger <markus.t.metzger@intel.com> + + * linux-low.c (linux_low_enable_btrace): Remove. + (linux_target_ops): Replace linux_low_enable_btrace with + linux_enable_btrace. + 2015-09-03 Yao Qi <yao.qi@linaro.org> * linux-aarch64-low.c (aarch64_insert_point): Call diff --git a/gdb/gdbserver/linux-low.c b/gdb/gdbserver/linux-low.c index f4c6029..4256bc5 100644 --- a/gdb/gdbserver/linux-low.c +++ b/gdb/gdbserver/linux-low.c @@ -6663,26 +6663,6 @@ linux_qxfer_libraries_svr4 (const char *annex, unsigned char *readbuf, #ifdef HAVE_LINUX_BTRACE -/* See to_enable_btrace target method. */ - -static struct btrace_target_info * -linux_low_enable_btrace (ptid_t ptid, const struct btrace_config *conf) -{ - struct btrace_target_info *tinfo; - - tinfo = linux_enable_btrace (ptid, conf); - - if (tinfo != NULL && tinfo->ptr_bits == 0) - { - struct thread_info *thread = find_thread_ptid (ptid); - struct regcache *regcache = get_thread_regcache (thread, 0); - - tinfo->ptr_bits = register_size (regcache->tdesc, 0) * 8; - } - - return tinfo; -} - /* See to_disable_btrace target method. */ static int @@ -6936,7 +6916,7 @@ static struct target_ops linux_target_ops = { linux_supports_agent, #ifdef HAVE_LINUX_BTRACE linux_supports_btrace, - linux_low_enable_btrace, + linux_enable_btrace, linux_low_disable_btrace, linux_low_read_btrace, linux_low_btrace_conf, diff --git a/gdb/nat/linux-btrace.c b/gdb/nat/linux-btrace.c index 51725ff..08478d8 100644 --- a/gdb/nat/linux-btrace.c +++ b/gdb/nat/linux-btrace.c @@ -24,6 +24,9 @@ #include "common-regcache.h" #include "gdb_wait.h" #include "x86-cpuid.h" +#include "filestuff.h" + +#include <inttypes.h> #ifdef HAVE_SYS_SYSCALL_H #include <sys/syscall.h> @@ -36,7 +39,6 @@ #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 @@ -189,56 +191,75 @@ perf_event_pt_event_type (int *type) return -1; } -static int -linux_determine_kernel_ptr_bits (void) +/* Try to determine the start address of the Linux kernel. */ + +static uint64_t +linux_determine_kernel_start (void) { - struct utsname utsn; - int errcode; + static uint64_t kernel_start; + static int cached; + FILE *file; - memset (&utsn, 0, sizeof (utsn)); + if (cached != 0) + return kernel_start; - errcode = uname (&utsn); - if (errcode < 0) - return 0; + cached = 1; - /* 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; + file = gdb_fopen_cloexec ("/proc/kallsyms", "r"); + if (file == NULL) + return kernel_start; - return 0; + while (!feof (file)) + { + char buffer[1024], symbol[8], *line; + uint64_t addr; + int match; + + line = fgets (buffer, sizeof (buffer), file); + if (line == NULL) + break; + + match = sscanf (line, "%" SCNx64 " %*[tT] %7s", &addr, symbol); + if (match != 2) + continue; + + if (strcmp (symbol, "_text") == 0) + { + kernel_start = addr; + break; + } + } + + fclose (file); + + 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 @@ -335,7 +356,7 @@ perf_event_read_bts (struct btrace_target_info* tinfo, const uint8_t *begin, 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. */ @@ -649,7 +670,6 @@ linux_enable_bts (ptid_t ptid, const struct btrace_config_bts *conf) tinfo = XCNEW (struct btrace_target_info); tinfo->ptid = ptid; - tinfo->ptr_bits = linux_determine_kernel_ptr_bits (); tinfo->conf.format = BTRACE_FORMAT_BTS; bts = &tinfo->variant.bts; @@ -782,7 +802,6 @@ linux_enable_pt (ptid_t ptid, const struct btrace_config_pt *conf) tinfo = XCNEW (struct btrace_target_info); tinfo->ptid = ptid; - tinfo->ptr_bits = 0; tinfo->conf.format = BTRACE_FORMAT_PT; pt = &tinfo->variant.pt; diff --git a/gdb/nat/linux-btrace.h b/gdb/nat/linux-btrace.h index 5ea87a8..042878c 100644 --- a/gdb/nat/linux-btrace.h +++ b/gdb/nat/linux-btrace.h @@ -100,11 +100,6 @@ struct btrace_target_info struct btrace_tinfo_pt pt; } variant; #endif /* HAVE_LINUX_PERF_EVENT_H */ - - /* The size of a pointer in bits for this thread. - The information is used to identify kernel addresses in order to skip - records from/to kernel space. */ - int ptr_bits; }; /* See to_supports_btrace in target.h. */ diff --git a/gdb/x86-linux-nat.c b/gdb/x86-linux-nat.c index fe52c1f..fa5ef30 100644 --- a/gdb/x86-linux-nat.c +++ b/gdb/x86-linux-nat.c @@ -264,12 +264,6 @@ x86_linux_enable_btrace (struct target_ops *self, ptid_t ptid, error (_("Could not enable branch tracing for %s: %s."), target_pid_to_str (ptid), safe_strerror (errno)); - /* Fill in the size of a pointer in bits. */ - if (tinfo->ptr_bits == 0) - { - gdbarch = target_thread_architecture (ptid); - tinfo->ptr_bits = gdbarch_ptr_bit (gdbarch); - } return tinfo; } |