From c2f4122d5cc2a21a441470336c8637b6a6965c6e Mon Sep 17 00:00:00 2001 From: Pedro Alves Date: Tue, 19 Jan 2016 12:18:14 +0000 Subject: Limit breakpoint re-set to the current program space Currently, we always re-set all locations of all breakpoints. This commit makes us re-set only locations of the current program space. If we loaded symbols to a program space (e.g., "file" command or some shared library was loaded), GDB must run through all breakpoints and determine if any new locations need to be added to the breakpoint. However, there's no reason to recreate locations for _other_ program spaces, as those haven't changed. Similarly, when we create a new inferior, through e.g., a fork, GDB must run through all breakpoints and determine if any new locations need to be added to the breakpoint. There's no reason to destroy the locations of the parent inferior and other inferiors. We know those won't change. In addition to being inneficient, resetting breakpoints of inferiors that are currently running is problematic, because: - some targets can't read memory while the inferior is running. - the inferior might exit while we're re-setting its breakpoints, which may confuse prologue skipping. I went through all the places where we call breakpoint_re_set, and it seems to me that all can be changed to only re-set locations of the current program space. The patch that reversed threads order in "info threads" etc. happened to make gdb.threads/fork-plus-thread.exp expose this problem when testing on x86/-m32. The problem was latent and masked out by chance by the code-cache: https://sourceware.org/ml/gdb-patches/2016-01/msg00213.html Tested on x86-64 F20, native (-m64/-m32) and extended-remote gdbserver. Fixes the regression discussed in the url above with --target_board=unix/-m32: -FAIL: gdb.threads/fork-plus-threads.exp: detach-on-fork=off: inferior 1 exited +PASS: gdb.threads/fork-plus-threads.exp: detach-on-fork=off: inferior 1 exited -FAIL: gdb.threads/fork-plus-threads.exp: detach-on-fork=off: no threads left (timeout) -FAIL: gdb.threads/fork-plus-threads.exp: detach-on-fork=off: only inferior 1 left (the program exited) +PASS: gdb.threads/fork-plus-threads.exp: detach-on-fork=off: no threads left +PASS: gdb.threads/fork-plus-threads.exp: detach-on-fork=off: only inferior 1 left gdb/ChangeLog: 2016-01-19 Pedro Alves * ax-gdb.c (agent_command_1): Adjust call to decode_line_full. * break-catch-throw.c (re_set_exception_catchpoint): Pass the current program space down to linespec decoding and breakpoint location updating. * breakpoint.c (parse_breakpoint_sals): Adjust calls to decode_line_full. (until_break_command): Adjust calls to decode_line_1. (base_breakpoint_decode_location, bkpt_decode_location): Add 'search_pspace' parameter. Pass it along. (bkpt_probe_create_sals_from_location): Adjust calls to parse_probes. (tracepoint_decode_location, tracepoint_probe_decode_location) (strace_marker_decode_location): Add 'search_pspace' parameter. Pass it along. (all_locations_are_pending): Rewrite to take a breakpoint and program space as arguments instead. (hoist_existing_locations): New function. (update_breakpoint_locations): Add 'filter_pspace' parameter. Use hoist_existing_locations instead of always removing all locations, and adjust to all_locations_are_pending change. (location_to_sals): Add 'search_pspace' parameter. Pass it along. Don't disable the breakpoint if there are other locations in another program space. (breakpoint_re_set_default): Adjust to pass down the current program space as filter program space. (decode_location_default): Add 'search_pspace' parameter and pass it along. (prepare_re_set_context): Don't switch program space here. (breakpoint_re_set): Use save_current_space_and_thread instead of save_current_program_space. * breakpoint.h (struct breakpoint_ops) : Add 'search_pspace' parameter. (update_breakpoint_locations): Add 'filter_pspace' parameter. * cli/cli-cmds.c (edit_command, list_command): Adjust calls to decode_line_1. * elfread.c (elf_gnu_ifunc_resolver_return_stop): Pass the current program space as filter program space. * linespec.c (struct linespec_state) : New field. (create_sals_line_offset, convert_explicit_location_to_sals) (parse_linespec): Pass the search program space down. (linespec_state_constructor): Add 'search_pspace' parameter. Store it. (linespec_parser_new): Add 'search_pspace' parameter and pass it along. (linespec_lex_to_end): Adjust. (decode_line_full, decode_line_1): Add 'search_pspace' parameter and pass it along. (decode_line_with_last_displayed): Adjust. (collect_symtabs_from_filename, symtabs_from_filename): New 'search_pspace' parameter. Use it. (find_function_symbols): Pass the search program space down. * linespec.h (decode_line_1, decode_line_full): Add 'search_pspace' parameter. * probe.c (parse_probes_in_pspace): New function, factored out from ... (parse_probes): ... this. Add 'search_pspace' parameter and use it. * probe.h (parse_probes): Add pspace' parameter. * python/python.c (gdbpy_decode_line): Adjust. * tracepoint.c (scope_info): Adjust. --- gdb/probe.c | 120 ++++++++++++++++++++++++++++++++++++------------------------ 1 file changed, 73 insertions(+), 47 deletions(-) (limited to 'gdb/probe.c') diff --git a/gdb/probe.c b/gdb/probe.c index 374e7a7..56f93da 100644 --- a/gdb/probe.c +++ b/gdb/probe.c @@ -41,18 +41,77 @@ DEF_VEC_O (bound_probe_s); +/* A helper for parse_probes that decodes a probe specification in + SEARCH_PSPACE. It appends matching SALs to RESULT. */ + +static void +parse_probes_in_pspace (const struct probe_ops *probe_ops, + struct program_space *search_pspace, + const char *objfile_namestr, + const char *provider, + const char *name, + struct symtabs_and_lines *result) +{ + struct objfile *objfile; + + ALL_PSPACE_OBJFILES (search_pspace, objfile) + { + VEC (probe_p) *probes; + struct probe *probe; + int ix; + + if (!objfile->sf || !objfile->sf->sym_probe_fns) + continue; + + if (objfile_namestr + && FILENAME_CMP (objfile_name (objfile), objfile_namestr) != 0 + && FILENAME_CMP (lbasename (objfile_name (objfile)), + objfile_namestr) != 0) + continue; + + probes = objfile->sf->sym_probe_fns->sym_get_probes (objfile); + + for (ix = 0; VEC_iterate (probe_p, probes, ix, probe); ix++) + { + struct symtab_and_line *sal; + + if (probe_ops != &probe_ops_any && probe->pops != probe_ops) + continue; + + if (provider && strcmp (probe->provider, provider) != 0) + continue; + + if (strcmp (probe->name, name) != 0) + continue; + + ++result->nelts; + result->sals = XRESIZEVEC (struct symtab_and_line, result->sals, + result->nelts); + sal = &result->sals[result->nelts - 1]; + + init_sal (sal); + + sal->pc = get_probe_address (probe, objfile); + sal->explicit_pc = 1; + sal->section = find_pc_overlay (sal->pc); + sal->pspace = search_pspace; + sal->probe = probe; + sal->objfile = objfile; + } + } +} + /* See definition in probe.h. */ struct symtabs_and_lines parse_probes (const struct event_location *location, + struct program_space *search_pspace, struct linespec_result *canonical) { char *arg_end, *arg; char *objfile_namestr = NULL, *provider = NULL, *name, *p; struct cleanup *cleanup; struct symtabs_and_lines result; - struct objfile *objfile; - struct program_space *pspace; const struct probe_ops *probe_ops; const char *arg_start, *cs; @@ -114,52 +173,19 @@ parse_probes (const struct event_location *location, if (objfile_namestr && *objfile_namestr == '\0') error (_("invalid objfile name")); - ALL_PSPACES (pspace) - ALL_PSPACE_OBJFILES (pspace, objfile) - { - VEC (probe_p) *probes; - struct probe *probe; - int ix; - - if (!objfile->sf || !objfile->sf->sym_probe_fns) - continue; - - if (objfile_namestr - && FILENAME_CMP (objfile_name (objfile), objfile_namestr) != 0 - && FILENAME_CMP (lbasename (objfile_name (objfile)), - objfile_namestr) != 0) - continue; - - probes = objfile->sf->sym_probe_fns->sym_get_probes (objfile); - - for (ix = 0; VEC_iterate (probe_p, probes, ix, probe); ix++) - { - struct symtab_and_line *sal; - - if (probe_ops != &probe_ops_any && probe->pops != probe_ops) - continue; - - if (provider && strcmp (probe->provider, provider) != 0) - continue; - - if (strcmp (probe->name, name) != 0) - continue; - - ++result.nelts; - result.sals = XRESIZEVEC (struct symtab_and_line, result.sals, - result.nelts); - sal = &result.sals[result.nelts - 1]; - - init_sal (sal); + if (search_pspace != NULL) + { + parse_probes_in_pspace (probe_ops, search_pspace, objfile_namestr, + provider, name, &result); + } + else + { + struct program_space *pspace; - sal->pc = get_probe_address (probe, objfile); - sal->explicit_pc = 1; - sal->section = find_pc_overlay (sal->pc); - sal->pspace = pspace; - sal->probe = probe; - sal->objfile = objfile; - } - } + ALL_PSPACES (pspace) + parse_probes_in_pspace (probe_ops, pspace, objfile_namestr, + provider, name, &result); + } if (result.nelts == 0) { -- cgit v1.1