| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Date: Thu, 2 Feb 2017 16:41:41 +0530
From: Ravi Bangoria <ravi.bangoria@...ux.vnet.ibm.com>
To: acme@...hat.com, alexis.berlemont@...il.com,
linux-kernel@...r.kernel.org
Cc: peterz@...radead.org, mingo@...hat.com,
alexander.shishkin@...ux.intel.com, mpe@...erman.id.au,
naveen.n.rao@...ux.vnet.ibm.com, mhiramat@...nel.org,
maddy@...ux.vnet.ibm.com,
Ravi Bangoria <ravi.bangoria@...ux.vnet.ibm.com>
Subject: [PATCH 3/5] perf/sdt/x86: Move OP parser to tools/perf/arch/x86/
SDT marker argument is in N@OP format. N is the size of argument and
OP is the actual assembly operand. OP is arch dependent component and
hence it's parsing logic also should be placed under tools/perf/arch/.
Signed-off-by: Ravi Bangoria <ravi.bangoria@...ux.vnet.ibm.com>
---
tools/perf/arch/x86/util/perf_regs.c | 93 ++++++++++++++++++++++++-
tools/perf/util/perf_regs.c | 9 ++-
tools/perf/util/perf_regs.h | 7 +-
tools/perf/util/probe-file.c | 127 +++++++++--------------------------
4 files changed, 134 insertions(+), 102 deletions(-)
diff --git a/tools/perf/arch/x86/util/perf_regs.c b/tools/perf/arch/x86/util/perf_regs.c
index d8a8dcf..34fcb0d 100644
--- a/tools/perf/arch/x86/util/perf_regs.c
+++ b/tools/perf/arch/x86/util/perf_regs.c
@@ -3,6 +3,7 @@
#include "../../perf.h"
#include "../../util/util.h"
#include "../../util/perf_regs.h"
+#include "../../util/debug.h"
const struct sample_reg sample_reg_masks[] = {
SMPL_REG(AX, PERF_REG_X86_AX),
@@ -87,7 +88,16 @@ static const struct sdt_name_reg sdt_reg_renamings[] = {
SDT_NAME_REG_END,
};
-int sdt_rename_register(char **pdesc, char *old_name)
+bool arch_sdt_probe_arg_supp(void)
+{
+ return true;
+}
+
+/*
+ * The table sdt_reg_renamings is used for adjusting gcc/gas-generated
+ * registers before filling the uprobe tracer interface.
+ */
+static int sdt_rename_register(char **pdesc, char *old_name)
{
const struct sdt_name_reg *rnames = sdt_reg_renamings;
char *new_desc, *old_desc = *pdesc;
@@ -129,3 +139,84 @@ int sdt_rename_register(char **pdesc, char *old_name)
return 0;
}
+
+/*
+ * x86 specific implementation
+ * return value:
+ * <0 : error
+ * 0 : success
+ * >0 : skip
+ */
+int arch_sdt_probe_parse_op(char **desc, const char **prefix)
+{
+ char *tmp;
+ int ret = 0;
+
+ /*
+ * The uprobe tracer format does not support all the addressing
+ * modes (notably: in x86 the scaled mode); so, we detect ','
+ * characters, if there is just one, there is no use converting
+ * the sdt arg into a uprobe one.
+ *
+ * Also it does not support constants; if we find one in the
+ * current argument, let's skip the argument.
+ */
+ if (strchr(*desc, ',') || strchr(*desc, '$')) {
+ pr_debug4("Skipping unsupported SDT argument; %s\n", *desc);
+ return 1;
+ }
+
+ /*
+ * If the argument addressing mode is indirect, we must check
+ * a few things...
+ */
+ tmp = strchr(*desc, '(');
+ if (tmp) {
+ int j;
+
+ /*
+ * ...if the addressing mode is indirect with a
+ * positive offset (ex.: "1608(%ax)"), we need to add
+ * a '+' prefix so as to be compliant with uprobe
+ * format.
+ */
+ if ((*desc)[0] != '+' && (*desc)[0] != '-')
+ *prefix = ((*desc)[0] == '(') ? "+0" : "+";
+
+ /*
+ * ...or if the addressing mode is indirect with a symbol
+ * as offset, the argument will not be supported by
+ * the uprobe tracer format; so, let's skip this one.
+ */
+ for (j = 0; j < tmp - *desc; j++) {
+ if ((*desc)[j] != '+' && (*desc)[j] != '-' &&
+ !isdigit((*desc)[j])) {
+ pr_debug4("Skipping unsupported SDT argument; "
+ "%s\n", *desc);
+ return 1;
+ }
+ }
+ }
+
+ /*
+ * The uprobe parser does not support all gas register names;
+ * so, we have to replace them (ex. for x86_64: %rax -> %ax);
+ * the loop below looks for the register names (starting with
+ * a '%' and tries to perform the needed renamings.
+ */
+ tmp = strchr(*desc, '%');
+ while (tmp) {
+ size_t offset = tmp - *desc;
+
+ ret = sdt_rename_register(desc, *desc + offset);
+ if (ret < 0)
+ return ret;
+
+ /*
+ * The *desc pointer might have changed; so, let's not
+ * try to reuse tmp for next lookup
+ */
+ tmp = strchr(*desc + offset + 1, '%');
+ }
+ return 0;
+}
diff --git a/tools/perf/util/perf_regs.c b/tools/perf/util/perf_regs.c
index a37e593..f2b3d0d 100644
--- a/tools/perf/util/perf_regs.c
+++ b/tools/perf/util/perf_regs.c
@@ -6,8 +6,13 @@ const struct sample_reg __weak sample_reg_masks[] = {
SMPL_REG_END
};
-int __weak sdt_rename_register(char **pdesc __maybe_unused,
- char *old_name __maybe_unused)
+bool __weak arch_sdt_probe_arg_supp(void)
+{
+ return false;
+}
+
+int __weak arch_sdt_probe_parse_op(char **op_ptr __maybe_unused,
+ const char **prefix __maybe_unused)
{
return 0;
}
diff --git a/tools/perf/util/perf_regs.h b/tools/perf/util/perf_regs.h
index 7544a15..86a2961 100644
--- a/tools/perf/util/perf_regs.h
+++ b/tools/perf/util/perf_regs.h
@@ -15,11 +15,8 @@ struct sample_reg {
extern const struct sample_reg sample_reg_masks[];
-/*
- * The table sdt_reg_renamings is used for adjusting gcc/gas-generated
- * registers before filling the uprobe tracer interface.
- */
-int sdt_rename_register(char **pdesc, char *old_name);
+bool arch_sdt_probe_arg_supp(void);
+int arch_sdt_probe_parse_op(char **op_ptr, const char **prefix);
#ifdef HAVE_PERF_REGS_SUPPORT
#include <perf_regs.h>
diff --git a/tools/perf/util/probe-file.c b/tools/perf/util/probe-file.c
index d8a169e..38eca3c 100644
--- a/tools/perf/util/probe-file.c
+++ b/tools/perf/util/probe-file.c
@@ -693,6 +693,25 @@ static const char * const type_to_suffix[] = {
"", ":u8", ":u16", "", ":u32", "", "", "", ":u64"
};
+/*
+ * Isolate the string number and convert it into a decimal value;
+ * this will be an index to get suffix of the uprobe name (defining
+ * the type)
+ */
+static int sdt_probe_parse_n(char *n_ptr, const char **suffix)
+{
+ long type_idx;
+
+ type_idx = strtol(n_ptr, NULL, 10);
+ if (type_idx < -8 || type_idx > 8) {
+ pr_debug4("Failed to get a valid sdt type\n");
+ return -1;
+ }
+
+ *suffix = type_to_suffix[type_idx + 8];
+ return 0;
+}
+
static int synthesize_sdt_probe_arg(struct strbuf *buf, int i, const char *arg)
{
char *tmp, *desc = strdup(arg);
@@ -704,109 +723,29 @@ static int synthesize_sdt_probe_arg(struct strbuf *buf, int i, const char *arg)
return ret;
}
+ /*
+ * Argument is in N@OP format. N is size of the argument and OP is
+ * the actual assembly operand. N can be omitted; in that case
+ * argument is just OP(without @).
+ */
tmp = strchr(desc, '@');
if (tmp) {
- long type_idx;
- /*
- * Isolate the string number and convert it into a
- * binary value; this will be an index to get suffix
- * of the uprobe name (defining the type)
- */
tmp[0] = '\0';
- type_idx = strtol(desc, NULL, 10);
- /* Check that the conversion went OK */
- if (type_idx == LONG_MIN || type_idx == LONG_MAX) {
- pr_debug4("Failed to parse sdt type\n");
- goto error;
- }
- /* Check that the converted value is OK */
- if (type_idx < -8 || type_idx > 8) {
- pr_debug4("Failed to get a valid sdt type\n");
- goto error;
- }
- suffix = type_to_suffix[type_idx + 8];
- /* Get rid of the sdt prefix which is now useless */
tmp++;
- memmove(desc, tmp, strlen(tmp) + 1);
- }
- /*
- * The uprobe tracer format does not support all the
- * addressing modes (notably: in x86 the scaled mode); so, we
- * detect ',' characters, if there is just one, there is no
- * use converting the sdt arg into a uprobe one.
- */
- if (strchr(desc, ',')) {
- pr_debug4("Skipping unsupported SDT argument; %s\n", desc);
- goto out;
- }
-
- /*
- * If the argument addressing mode is indirect, we must check
- * a few things...
- */
- tmp = strchr(desc, '(');
- if (tmp) {
- int j;
-
- /*
- * ...if the addressing mode is indirect with a
- * positive offset (ex.: "1608(%ax)"), we need to add
- * a '+' prefix so as to be compliant with uprobe
- * format.
- */
- if (desc[0] != '+' && desc[0] != '-')
- prefix = "+";
-
- /*
- * ...or if the addressing mode is indirect with a symbol
- * as offset, the argument will not be supported by
- * the uprobe tracer format; so, let's skip this one.
- */
- for (j = 0; j < tmp - desc; j++) {
- if (desc[j] != '+' && desc[j] != '-' &&
- !isdigit(desc[j])) {
- pr_debug4("Skipping unsupported SDT argument; "
- "%s\n", desc);
- goto out;
- }
- }
- }
-
- /*
- * The uprobe tracer format does not support constants; if we
- * find one in the current argument, let's skip the argument.
- */
- if (strchr(desc, '$')) {
- pr_debug4("Skipping unsupported SDT argument; %s\n", desc);
- goto out;
- }
-
- /*
- * The uprobe parser does not support all gas register names;
- * so, we have to replace them (ex. for x86_64: %rax -> %ax);
- * the loop below looks for the register names (starting with
- * a '%' and tries to perform the needed renamings.
- */
- tmp = strchr(desc, '%');
- while (tmp) {
- size_t offset = tmp - desc;
-
- ret = sdt_rename_register(&desc, desc + offset);
- if (ret < 0)
+ if (sdt_probe_parse_n(desc, &suffix))
goto error;
-
- /*
- * The desc pointer might have changed; so, let's not
- * try to reuse tmp for next lookup
- */
- tmp = strchr(desc + offset + 1, '%');
+ memmove(desc, tmp, strlen(tmp) + 1);
}
- if (strbuf_addf(buf, " arg%d=%s%s%s", i + 1, prefix, desc, suffix) < 0)
+ ret = arch_sdt_probe_parse_op(&desc, &prefix);
+ if (ret < 0)
+ goto error;
+
+ if (ret == 0 &&
+ strbuf_addf(buf, " arg%d=%s%s%s", i + 1, prefix, desc, suffix) < 0)
goto error;
-out:
ret = 0;
error:
free(desc);
@@ -829,7 +768,7 @@ static char *synthesize_sdt_probe_command(struct sdt_note *note,
sdt_note__get_addr(note)) < 0)
goto error;
- if (!note->args)
+ if (!note->args || !arch_sdt_probe_arg_supp())
goto out;
if (note->args) {
--
2.9.3
Powered by blists - more mailing lists