summaryrefslogtreecommitdiffstats
path: root/tapsets.cxx
diff options
context:
space:
mode:
Diffstat (limited to 'tapsets.cxx')
-rw-r--r--tapsets.cxx324
1 files changed, 4 insertions, 320 deletions
diff --git a/tapsets.cxx b/tapsets.cxx
index e88928dc..f83924ab 100644
--- a/tapsets.cxx
+++ b/tapsets.cxx
@@ -43,7 +43,6 @@ extern "C" {
#include <dwarf.h>
#include <elf.h>
#include <obstack.h>
-#include <regex.h>
#include <glob.h>
#include <fnmatch.h>
#include <stdio.h>
@@ -550,19 +549,6 @@ struct dwarf_query : public base_query
int line,
Dwarf_Die *scope_die,
Dwarf_Addr addr);
- string get_blacklist_section(Dwarf_Addr addr);
-
- regex_t blacklist_func; // function/statement probes
- regex_t blacklist_func_ret; // only for .return probes
- regex_t blacklist_file; // file name
- void build_blacklist();
-
- bool blacklisted_p(const string& funcname,
- const string& filename,
- int line,
- const string& module,
- const string& section,
- Dwarf_Addr addr);
// Extracted parameters.
string function_val;
@@ -705,7 +691,6 @@ dwarf_query::dwarf_query(systemtap_session & sess,
else if (has_statement_str)
spec_type = parse_function_spec(statement_str_val);
- build_blacklist(); // XXX: why not reuse amongst dwarf_query instances?
dbinfo_reqt = assess_dbinfo_reqt();
query_done = false;
}
@@ -872,138 +857,6 @@ dwarf_query::handle_query_module()
}
-void
-dwarf_query::build_blacklist()
-{
- // No blacklist for userspace.
- if (has_process)
- return;
-
- // We build up the regexps in these strings
-
- // Add ^ anchors at the front; $ will be added just before regcomp.
-
- string blfn = "^(";
- string blfn_ret = "^(";
- string blfile = "^(";
-
- blfile += "kernel/kprobes.c"; // first alternative, no "|"
- blfile += "|arch/.*/kernel/kprobes.c";
- // Older kernels need ...
- blfile += "|include/asm/io.h";
- blfile += "|include/asm/bitops.h";
- // While newer ones need ...
- blfile += "|arch/.*/include/asm/io.h";
- blfile += "|arch/.*/include/asm/bitops.h";
- blfile += "|drivers/ide/ide-iops.c";
-
- // XXX: it would be nice if these blacklisted functions were pulled
- // in dynamically, instead of being statically defined here.
- // Perhaps it could be populated from script files. A "noprobe
- // kernel.function("...")" construct might do the trick.
-
- // Most of these are marked __kprobes in newer kernels. We list
- // them here (anyway) so the translator can block them on older
- // kernels that don't have the __kprobes function decorator. This
- // also allows detection of problems at translate- rather than
- // run-time.
-
- blfn += "atomic_notifier_call_chain"; // first blfn; no "|"
- blfn += "|default_do_nmi";
- blfn += "|__die";
- blfn += "|die_nmi";
- blfn += "|do_debug";
- blfn += "|do_general_protection";
- blfn += "|do_int3";
- blfn += "|do_IRQ";
- blfn += "|do_page_fault";
- blfn += "|do_sparc64_fault";
- blfn += "|do_trap";
- blfn += "|dummy_nmi_callback";
- blfn += "|flush_icache_range";
- blfn += "|ia64_bad_break";
- blfn += "|ia64_do_page_fault";
- blfn += "|ia64_fault";
- blfn += "|io_check_error";
- blfn += "|mem_parity_error";
- blfn += "|nmi_watchdog_tick";
- blfn += "|notifier_call_chain";
- blfn += "|oops_begin";
- blfn += "|oops_end";
- blfn += "|program_check_exception";
- blfn += "|single_step_exception";
- blfn += "|sync_regs";
- blfn += "|unhandled_fault";
- blfn += "|unknown_nmi_error";
-
- // Lots of locks
- blfn += "|.*raw_.*lock.*";
- blfn += "|.*read_.*lock.*";
- blfn += "|.*write_.*lock.*";
- blfn += "|.*spin_.*lock.*";
- blfn += "|.*rwlock_.*lock.*";
- blfn += "|.*rwsem_.*lock.*";
- blfn += "|.*mutex_.*lock.*";
- blfn += "|raw_.*";
- blfn += "|.*seq_.*lock.*";
-
- // atomic functions
- blfn += "|atomic_.*";
- blfn += "|atomic64_.*";
-
- // few other problematic cases
- blfn += "|get_bh";
- blfn += "|put_bh";
-
- // Experimental
- blfn += "|.*apic.*|.*APIC.*";
- blfn += "|.*softirq.*";
- blfn += "|.*IRQ.*";
- blfn += "|.*_intr.*";
- blfn += "|__delay";
- blfn += "|.*kernel_text.*";
- blfn += "|get_current";
- blfn += "|current_.*";
- blfn += "|.*exception_tables.*";
- blfn += "|.*setup_rt_frame.*";
-
- // PR 5759, CONFIG_PREEMPT kernels
- blfn += "|.*preempt_count.*";
- blfn += "|preempt_schedule";
-
- // These functions don't return, so return probes would never be recovered
- blfn_ret += "do_exit"; // no "|"
- blfn_ret += "|sys_exit";
- blfn_ret += "|sys_exit_group";
-
- // __switch_to changes "current" on x86_64 and i686, so return probes
- // would cause kernel panic, and it is marked as "__kprobes" on x86_64
- if (sess.architecture == "x86_64")
- blfn += "|__switch_to";
- if (sess.architecture == "i686")
- blfn_ret += "|__switch_to";
-
- blfn += ")$";
- blfn_ret += ")$";
- blfile += ")$";
-
- if (sess.verbose > 2)
- {
- clog << "blacklist regexps:" << endl;
- clog << "blfn: " << blfn << endl;
- clog << "blfn_ret: " << blfn_ret << endl;
- clog << "blfile: " << blfile << endl;
- }
-
- int rc = regcomp (& blacklist_func, blfn.c_str(), REG_NOSUB|REG_EXTENDED);
- if (rc) throw semantic_error ("blacklist_func regcomp failed");
- rc = regcomp (& blacklist_func_ret, blfn_ret.c_str(), REG_NOSUB|REG_EXTENDED);
- if (rc) throw semantic_error ("blacklist_func_ret regcomp failed");
- rc = regcomp (& blacklist_file, blfile.c_str(), REG_NOSUB|REG_EXTENDED);
- if (rc) throw semantic_error ("blacklist_file regcomp failed");
-}
-
-
function_spec_type
dwarf_query::parse_function_spec(string & spec)
{
@@ -1094,129 +947,6 @@ dwarf_query::parse_function_spec(string & spec)
}
-#if 0
-// Forward declaration.
-static int query_kernel_module (Dwfl_Module *, void **, const char *,
- Dwarf_Addr, void *);
-#endif
-
-
-// XXX: pull this into dwflpp
-static bool
-in_kprobes_function(systemtap_session& sess, Dwarf_Addr addr)
-{
- if (sess.sym_kprobes_text_start != 0 && sess.sym_kprobes_text_end != 0)
- {
- // If the probe point address is anywhere in the __kprobes
- // address range, we can't use this probe point.
- if (addr >= sess.sym_kprobes_text_start && addr < sess.sym_kprobes_text_end)
- return true;
- }
- return false;
-}
-
-
-bool
-dwarf_query::blacklisted_p(const string& funcname,
- const string& filename,
- int,
- const string& module,
- const string& section,
- Dwarf_Addr addr)
-{
- if (has_process)
- return false; // no blacklist for userspace
-
- if (section.substr(0, 6) == string(".init.") ||
- section.substr(0, 6) == string(".exit.") ||
- section.substr(0, 9) == string(".devinit.") ||
- section.substr(0, 9) == string(".devexit.") ||
- section.substr(0, 9) == string(".cpuinit.") ||
- section.substr(0, 9) == string(".cpuexit.") ||
- section.substr(0, 9) == string(".meminit.") ||
- section.substr(0, 9) == string(".memexit."))
- {
- // NB: module .exit. routines could be probed in theory:
- // if the exit handler in "struct module" is diverted,
- // first inserting the kprobes
- // then allowing the exit code to run
- // then removing these kprobes
- if (sess.verbose>1)
- clog << " skipping - init/exit";
- return true;
- }
-
- // Check for function marked '__kprobes'.
- if (module == TOK_KERNEL && in_kprobes_function(sess, addr))
- {
- if (sess.verbose>1)
- clog << " skipping - __kprobes";
- return true;
- }
-
- // Check probe point against blacklist.
- int goodfn = regexec (&blacklist_func, funcname.c_str(), 0, NULL, 0);
- if (has_return)
- goodfn = goodfn && regexec (&blacklist_func_ret, funcname.c_str(), 0, NULL, 0);
- int goodfile = regexec (&blacklist_file, filename.c_str(), 0, NULL, 0);
-
- if (! (goodfn && goodfile))
- {
- if (sess.guru_mode)
- {
- if (sess.verbose>1)
- clog << " guru mode enabled - ignoring blacklist";
- }
- else
- {
- if (sess.verbose>1)
- clog << " skipping - blacklisted";
- return true;
- }
- }
-
- // This probe point is not blacklisted.
- return false;
-}
-
-string dwarf_query::get_blacklist_section(Dwarf_Addr addr)
-{
- string blacklist_section;
- Dwarf_Addr bias;
- // We prefer dwfl_module_getdwarf to dwfl_module_getelf here,
- // because dwfl_module_getelf can force costly section relocations
- // we don't really need, while either will do for this purpose.
- Elf* elf = (dwarf_getelf (dwfl_module_getdwarf (dw.module, &bias))
- ?: dwfl_module_getelf (dw.module, &bias));
-
- Dwarf_Addr offset = addr - bias;
- if (elf)
- {
- Elf_Scn* scn = 0;
- size_t shstrndx;
- dwfl_assert ("getshstrndx", elf_getshstrndx (elf, &shstrndx));
- while ((scn = elf_nextscn (elf, scn)) != NULL)
- {
- GElf_Shdr shdr_mem;
- GElf_Shdr *shdr = gelf_getshdr (scn, &shdr_mem);
- if (! shdr) continue; // XXX error?
-
- if (!(shdr->sh_flags & SHF_ALLOC))
- continue;
-
- GElf_Addr start = shdr->sh_addr;
- GElf_Addr end = start + shdr->sh_size;
- if (! (offset >= start && offset < end))
- continue;
-
- blacklist_section = elf_strptr (elf, shstrndx, shdr->sh_name);
- break;
- }
- }
- return blacklist_section;
-}
-
-
void
dwarf_query::add_probe_point(const string& funcname,
const char* filename,
@@ -1225,40 +955,13 @@ dwarf_query::add_probe_point(const string& funcname,
Dwarf_Addr addr)
{
string reloc_section; // base section for relocation purposes
- Dwarf_Addr reloc_addr = addr; // relocated
+ Dwarf_Addr reloc_addr; // relocated
string blacklist_section; // linking section for blacklist purposes
const string& module = dw.module_name; // "kernel" or other
assert (! has_absolute); // already handled in dwarf_builder::build()
- if (!dw.module)
- {
- assert(module == TOK_KERNEL);
- reloc_section = "";
- blacklist_section = "";
- }
- else if (dwfl_module_relocations (dw.module) > 0)
- {
- // This is a relocatable module; libdwfl already knows its
- // sections, so we can relativize addr.
- int idx = dwfl_module_relocate_address (dw.module, &reloc_addr);
- const char* r_s = dwfl_module_relocation_info (dw.module, idx, NULL);
- if (r_s)
- reloc_section = r_s;
- blacklist_section = reloc_section;
-
- if(reloc_section == "" && dwfl_module_relocations (dw.module) == 1)
- {
- blacklist_section = this->get_blacklist_section(addr);
- reloc_section = ".dynamic";
- reloc_addr = addr;
- }
- }
- else
- {
- blacklist_section = this->get_blacklist_section(addr);
- reloc_section = ".absolute";
- }
+ reloc_addr = dw.relocate_address(addr, reloc_section, blacklist_section);
if (sess.verbose > 1)
{
@@ -1274,7 +977,8 @@ dwarf_query::add_probe_point(const string& funcname,
clog << " pc=0x" << hex << addr << dec;
}
- bool bad = blacklisted_p (funcname, filename, line, module, blacklist_section, addr);
+ bool bad = dw.blacklisted_p (funcname, filename, line, module,
+ blacklist_section, addr, has_return);
if (sess.verbose > 1)
clog << endl;
@@ -1777,26 +1481,6 @@ query_cu (Dwarf_Die * cudie, void * arg)
}
-#if 0
-static int
-query_kernel_module (Dwfl_Module *mod,
- void **,
- const char *name,
- Dwarf_Addr,
- void *arg)
-{
- if (TOK_KERNEL == name)
- {
- Dwfl_Module **m = (Dwfl_Module **)arg;
-
- *m = mod;
- return DWARF_CB_ABORT;
- }
- return DWARF_CB_OK;
-}
-#endif
-
-
static void
validate_module_elf (Dwfl_Module *mod, const char *name, base_query *q)
{
generated by cgit (git 2.34.1) at 2025-08-03 08:06:02 +0000