From dd5477ff3ba978892014ea5f988cb1bf04aa505e Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 6 Apr 2011 13:21:17 -0400 Subject: ftrace/trivial: Clean up recordmcount.c to use Linux style comparisons The Linux ftrace subsystem style for comparing is: var == 1 var > 0 and not: 1 == var 0 < var It is considered that Linux developers are smart enough not to do the if (var = 1) mistake. Cc: John Reiser Link: http://lkml.kernel.org/r/20110421023737.290712238@goodmis.org Signed-off-by: Steven Rostedt --- scripts/recordmcount.c | 48 ++++++++++++++++++++++++------------------------ scripts/recordmcount.h | 16 ++++++++-------- 2 files changed, 32 insertions(+), 32 deletions(-) (limited to 'scripts') diff --git a/scripts/recordmcount.c b/scripts/recordmcount.c index f9f6f52..37afe0e 100644 --- a/scripts/recordmcount.c +++ b/scripts/recordmcount.c @@ -78,7 +78,7 @@ static off_t ulseek(int const fd, off_t const offset, int const whence) { off_t const w = lseek(fd, offset, whence); - if ((off_t)-1 == w) { + if (w == (off_t)-1) { perror("lseek"); fail_file(); } @@ -111,7 +111,7 @@ static void * umalloc(size_t size) { void *const addr = malloc(size); - if (0 == addr) { + if (addr == 0) { fprintf(stderr, "malloc failed: %zu bytes\n", size); fail_file(); } @@ -136,7 +136,7 @@ static void *mmap_file(char const *fname) void *addr; fd_map = open(fname, O_RDWR); - if (0 > fd_map || 0 > fstat(fd_map, &sb)) { + if (fd_map < 0 || fstat(fd_map, &sb) < 0) { perror(fname); fail_file(); } @@ -147,7 +147,7 @@ static void *mmap_file(char const *fname) addr = mmap(0, sb.st_size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd_map, 0); mmap_failed = 0; - if (MAP_FAILED == addr) { + if (addr == MAP_FAILED) { mmap_failed = 1; addr = umalloc(sb.st_size); uread(fd_map, addr, sb.st_size); @@ -206,12 +206,12 @@ static uint32_t (*w2)(uint16_t); static int is_mcounted_section_name(char const *const txtname) { - return 0 == strcmp(".text", txtname) || - 0 == strcmp(".ref.text", txtname) || - 0 == strcmp(".sched.text", txtname) || - 0 == strcmp(".spinlock.text", txtname) || - 0 == strcmp(".irqentry.text", txtname) || - 0 == strcmp(".text.unlikely", txtname); + return strcmp(".text", txtname) == 0 || + strcmp(".ref.text", txtname) == 0 || + strcmp(".sched.text", txtname) == 0 || + strcmp(".spinlock.text", txtname) == 0 || + strcmp(".irqentry.text", txtname) == 0 || + strcmp(".text.unlikely", txtname) == 0; } /* 32 bit and 64 bit are very similar */ @@ -270,7 +270,7 @@ do_file(char const *const fname) fail_file(); } break; case ELFDATA2LSB: { - if (1 != *(unsigned char const *)&endian) { + if (*(unsigned char const *)&endian != 1) { /* main() is big endian, file.o is little endian. */ w = w4rev; w2 = w2rev; @@ -278,7 +278,7 @@ do_file(char const *const fname) } } break; case ELFDATA2MSB: { - if (0 != *(unsigned char const *)&endian) { + if (*(unsigned char const *)&endian != 0) { /* main() is little endian, file.o is big endian. */ w = w4rev; w2 = w2rev; @@ -286,9 +286,9 @@ do_file(char const *const fname) } } break; } /* end switch */ - if (0 != memcmp(ELFMAG, ehdr->e_ident, SELFMAG) - || ET_REL != w2(ehdr->e_type) - || EV_CURRENT != ehdr->e_ident[EI_VERSION]) { + if (memcmp(ELFMAG, ehdr->e_ident, SELFMAG) != 0 + || w2(ehdr->e_type) != ET_REL + || ehdr->e_ident[EI_VERSION] != EV_CURRENT) { fprintf(stderr, "unrecognized ET_REL file %s\n", fname); fail_file(); } @@ -321,15 +321,15 @@ do_file(char const *const fname) fail_file(); } break; case ELFCLASS32: { - if (sizeof(Elf32_Ehdr) != w2(ehdr->e_ehsize) - || sizeof(Elf32_Shdr) != w2(ehdr->e_shentsize)) { + if (w2(ehdr->e_ehsize) != sizeof(Elf32_Ehdr) + || w2(ehdr->e_shentsize) != sizeof(Elf32_Shdr)) { fprintf(stderr, "unrecognized ET_REL file: %s\n", fname); fail_file(); } - if (EM_S390 == w2(ehdr->e_machine)) + if (w2(ehdr->e_machine) == EM_S390) reltype = R_390_32; - if (EM_MIPS == w2(ehdr->e_machine)) { + if (w2(ehdr->e_machine) == EM_MIPS) { reltype = R_MIPS_32; is_fake_mcount32 = MIPS32_is_fake_mcount; } @@ -337,15 +337,15 @@ do_file(char const *const fname) } break; case ELFCLASS64: { Elf64_Ehdr *const ghdr = (Elf64_Ehdr *)ehdr; - if (sizeof(Elf64_Ehdr) != w2(ghdr->e_ehsize) - || sizeof(Elf64_Shdr) != w2(ghdr->e_shentsize)) { + if (w2(ghdr->e_ehsize) != sizeof(Elf64_Ehdr) + || w2(ghdr->e_shentsize) != sizeof(Elf64_Shdr)) { fprintf(stderr, "unrecognized ET_REL file: %s\n", fname); fail_file(); } - if (EM_S390 == w2(ghdr->e_machine)) + if (w2(ghdr->e_machine) == EM_S390) reltype = R_390_64; - if (EM_MIPS == w2(ghdr->e_machine)) { + if (w2(ghdr->e_machine) == EM_MIPS) { reltype = R_MIPS_64; Elf64_r_sym = MIPS64_r_sym; Elf64_r_info = MIPS64_r_info; @@ -371,7 +371,7 @@ main(int argc, char const *argv[]) } /* Process each file in turn, allowing deep failure. */ - for (--argc, ++argv; 0 < argc; --argc, ++argv) { + for (--argc, ++argv; argc > 0; --argc, ++argv) { int const sjval = setjmp(jmpenv); int len; diff --git a/scripts/recordmcount.h b/scripts/recordmcount.h index baf187b..ac7b330 100644 --- a/scripts/recordmcount.h +++ b/scripts/recordmcount.h @@ -275,12 +275,12 @@ static uint_t *sift_rel_mcount(uint_t *mlocp, Elf_Sym const *const symp = &sym0[Elf_r_sym(relp)]; char const *symname = &str0[w(symp->st_name)]; - char const *mcount = '_' == gpfx ? "_mcount" : "mcount"; + char const *mcount = gpfx == '_' ? "_mcount" : "mcount"; - if ('.' == symname[0]) + if (symname[0] == '.') ++symname; /* ppc64 hack */ - if (0 == strcmp(mcount, symname) || - (altmcount && 0 == strcmp(altmcount, symname))) + if (strcmp(mcount, symname) == 0 || + (altmcount && strcmp(altmcount, symname) == 0)) mcountsym = Elf_r_sym(relp); } @@ -290,7 +290,7 @@ static uint_t *sift_rel_mcount(uint_t *mlocp, mrelp->r_offset = _w(offbase + ((void *)mlocp - (void *)mloc0)); Elf_r_info(mrelp, recsym, reltype); - if (sizeof(Elf_Rela) == rel_entsize) { + if (rel_entsize == sizeof(Elf_Rela)) { ((Elf_Rela *)mrelp)->r_addend = addend; *mlocp++ = 0; } else @@ -354,12 +354,12 @@ __has_rel_mcount(Elf_Shdr const *const relhdr, /* is SHT_REL or SHT_RELA */ Elf_Shdr const *const txthdr = &shdr0[w(relhdr->sh_info)]; char const *const txtname = &shstrtab[w(txthdr->sh_name)]; - if (0 == strcmp("__mcount_loc", txtname)) { + if (strcmp("__mcount_loc", txtname) == 0) { fprintf(stderr, "warning: __mcount_loc already exists: %s\n", fname); succeed_file(); } - if (SHT_PROGBITS != w(txthdr->sh_type) || + if (w(txthdr->sh_type) != SHT_PROGBITS || !is_mcounted_section_name(txtname)) return NULL; return txtname; @@ -370,7 +370,7 @@ static char const *has_rel_mcount(Elf_Shdr const *const relhdr, char const *const shstrtab, char const *const fname) { - if (SHT_REL != w(relhdr->sh_type) && SHT_RELA != w(relhdr->sh_type)) + if (w(relhdr->sh_type) != SHT_REL && w(relhdr->sh_type) != SHT_RELA) return NULL; return __has_rel_mcount(relhdr, shdr0, shstrtab, fname); } -- cgit v1.1 From e90b0c8bf211958a296d60369fecd51b35864407 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 6 Apr 2011 13:32:24 -0400 Subject: ftrace/trivial: Clean up record mcount to use Linux switch style The Linux style for switch statements is: switch (var) { case x: [...] break; } Not: switch (var) { case x: { [...] } break; Cc: John Reiser Link: http://lkml.kernel.org/r/20110421023737.523968644@goodmis.org Signed-off-by: Steven Rostedt --- scripts/recordmcount.c | 43 ++++++++++++++++++++++--------------------- 1 file changed, 22 insertions(+), 21 deletions(-) (limited to 'scripts') diff --git a/scripts/recordmcount.c b/scripts/recordmcount.c index 37afe0e..4ebd839 100644 --- a/scripts/recordmcount.c +++ b/scripts/recordmcount.c @@ -264,27 +264,27 @@ do_file(char const *const fname) w8 = w8nat; switch (ehdr->e_ident[EI_DATA]) { static unsigned int const endian = 1; - default: { + default: fprintf(stderr, "unrecognized ELF data encoding %d: %s\n", ehdr->e_ident[EI_DATA], fname); fail_file(); - } break; - case ELFDATA2LSB: { + break; + case ELFDATA2LSB: if (*(unsigned char const *)&endian != 1) { /* main() is big endian, file.o is little endian. */ w = w4rev; w2 = w2rev; w8 = w8rev; } - } break; - case ELFDATA2MSB: { + break; + case ELFDATA2MSB: if (*(unsigned char const *)&endian != 0) { /* main() is little endian, file.o is big endian. */ w = w4rev; w2 = w2rev; w8 = w8rev; } - } break; + break; } /* end switch */ if (memcmp(ELFMAG, ehdr->e_ident, SELFMAG) != 0 || w2(ehdr->e_type) != ET_REL @@ -295,11 +295,11 @@ do_file(char const *const fname) gpfx = 0; switch (w2(ehdr->e_machine)) { - default: { + default: fprintf(stderr, "unrecognized e_machine %d %s\n", w2(ehdr->e_machine), fname); fail_file(); - } break; + break; case EM_386: reltype = R_386_32; break; case EM_ARM: reltype = R_ARM_ABS32; altmcount = "__gnu_mcount_nc"; @@ -315,12 +315,12 @@ do_file(char const *const fname) } /* end switch */ switch (ehdr->e_ident[EI_CLASS]) { - default: { + default: fprintf(stderr, "unrecognized ELF class %d %s\n", ehdr->e_ident[EI_CLASS], fname); fail_file(); - } break; - case ELFCLASS32: { + break; + case ELFCLASS32: if (w2(ehdr->e_ehsize) != sizeof(Elf32_Ehdr) || w2(ehdr->e_shentsize) != sizeof(Elf32_Shdr)) { fprintf(stderr, @@ -334,7 +334,7 @@ do_file(char const *const fname) is_fake_mcount32 = MIPS32_is_fake_mcount; } do32(ehdr, fname, reltype); - } break; + break; case ELFCLASS64: { Elf64_Ehdr *const ghdr = (Elf64_Ehdr *)ehdr; if (w2(ghdr->e_ehsize) != sizeof(Elf64_Ehdr) @@ -352,7 +352,8 @@ do_file(char const *const fname) is_fake_mcount64 = MIPS64_is_fake_mcount; } do64(ghdr, fname, reltype); - } break; + break; + } } /* end switch */ cleanup(); @@ -386,23 +387,23 @@ main(int argc, char const *argv[]) continue; switch (sjval) { - default: { + default: fprintf(stderr, "internal error: %s\n", argv[0]); exit(1); - } break; - case SJ_SETJMP: { /* normal sequence */ + break; + case SJ_SETJMP: /* normal sequence */ /* Avoid problems if early cleanup() */ fd_map = -1; ehdr_curr = NULL; mmap_failed = 1; do_file(argv[0]); - } break; - case SJ_FAIL: { /* error in do_file or below */ + break; + case SJ_FAIL: /* error in do_file or below */ ++n_error; - } break; - case SJ_SUCCEED: { /* premature success */ + break; + case SJ_SUCCEED: /* premature success */ /* do nothing */ - } break; + break; } /* end switch */ } return !!n_error; -- cgit v1.1 From 9f087e7612115b7a201d4f3392a95ac7408948ab Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 6 Apr 2011 14:10:22 -0400 Subject: ftrace: Add .kprobe.text section to whitelist for recordmcount.c The .kprobe.text section is safe to modify mcount to nop and tracing. Add it to the whitelist in recordmcount.c and recordmcount.pl. Cc: John Reiser Cc: Masami Hiramatsu Link: http://lkml.kernel.org/r/20110421023737.743350547@goodmis.org Signed-off-by: Steven Rostedt --- scripts/recordmcount.c | 1 + scripts/recordmcount.pl | 1 + 2 files changed, 2 insertions(+) (limited to 'scripts') diff --git a/scripts/recordmcount.c b/scripts/recordmcount.c index 4ebd839..37c5965 100644 --- a/scripts/recordmcount.c +++ b/scripts/recordmcount.c @@ -211,6 +211,7 @@ is_mcounted_section_name(char const *const txtname) strcmp(".sched.text", txtname) == 0 || strcmp(".spinlock.text", txtname) == 0 || strcmp(".irqentry.text", txtname) == 0 || + strcmp(".kprobes.text", txtname) == 0 || strcmp(".text.unlikely", txtname) == 0; } diff --git a/scripts/recordmcount.pl b/scripts/recordmcount.pl index 4be0dee..a871cd4 100755 --- a/scripts/recordmcount.pl +++ b/scripts/recordmcount.pl @@ -134,6 +134,7 @@ my %text_sections = ( ".sched.text" => 1, ".spinlock.text" => 1, ".irqentry.text" => 1, + ".kprobes.text" => 1, ".text.unlikely" => 1, ); -- cgit v1.1 From 8abd5724a7f1631ab2276954156c629d4d17149a Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 13 Apr 2011 13:31:08 -0400 Subject: ftrace/recordmcount: Modify only executable sections PROGBITS is not enough to determine if the section should be modified or not. Only process sections that are marked as executable. Cc: John Reiser Link: http://lkml.kernel.org/r/20110421023737.991485123@goodmis.org Signed-off-by: Steven Rostedt --- scripts/recordmcount.h | 1 + 1 file changed, 1 insertion(+) (limited to 'scripts') diff --git a/scripts/recordmcount.h b/scripts/recordmcount.h index ac7b330..7f8d5c4 100644 --- a/scripts/recordmcount.h +++ b/scripts/recordmcount.h @@ -360,6 +360,7 @@ __has_rel_mcount(Elf_Shdr const *const relhdr, /* is SHT_REL or SHT_RELA */ succeed_file(); } if (w(txthdr->sh_type) != SHT_PROGBITS || + !(w(txthdr->sh_flags) & SHF_EXECINSTR) || !is_mcounted_section_name(txtname)) return NULL; return txtname; -- cgit v1.1 From ffd618fa39284f8cc343894b566dd42ec6e74e77 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Fri, 8 Apr 2011 03:58:48 -0400 Subject: ftrace/recordmcount: Make ignored mcount calls into nops at compile time There are sections that are ignored by ftrace for the function tracing because the text is in a section that can be removed without notice. The mcount calls in these sections are ignored and ftrace never sees them. The downside of this is that the functions in these sections still call mcount. Although the mcount function is defined in assembly simply as a return, this added overhead is unnecessary. The solution is to convert these callers into nops at compile time. A better solution is to add 'notrace' to the section markers, but as new sections come up all the time, it would be nice that they are delt with when they are created. Later patches will deal with finding these sections and doing the proper solution. Thanks to H. Peter Anvin for giving me the right nops to use for x86. Cc: "H. Peter Anvin" Cc: John Reiser Link: http://lkml.kernel.org/r/20110421023738.237101176@goodmis.org Signed-off-by: Steven Rostedt --- scripts/recordmcount.c | 40 ++++++++++++++++++++++-- scripts/recordmcount.h | 82 +++++++++++++++++++++++++++++++++++++++++++++++--- 2 files changed, 116 insertions(+), 6 deletions(-) (limited to 'scripts') diff --git a/scripts/recordmcount.c b/scripts/recordmcount.c index 37c5965..78054a4 100644 --- a/scripts/recordmcount.c +++ b/scripts/recordmcount.c @@ -118,6 +118,34 @@ umalloc(size_t size) return addr; } +static unsigned char ideal_nop5_x86_64[5] = { 0x0f, 0x1f, 0x44, 0x00, 0x00 }; +static unsigned char ideal_nop5_x86_32[5] = { 0x3e, 0x8d, 0x74, 0x26, 0x00 }; +static unsigned char *ideal_nop; + +static char rel_type_nop; + +static int (*make_nop)(void *map, size_t const offset); + +static int make_nop_x86(void *map, size_t const offset) +{ + uint32_t *ptr; + unsigned char *op; + + /* Confirm we have 0xe8 0x0 0x0 0x0 0x0 */ + ptr = map + offset; + if (*ptr != 0) + return -1; + + op = map + offset - 1; + if (*op != 0xe8) + return -1; + + /* convert to nop */ + ulseek(fd_map, offset - 1, SEEK_SET); + uwrite(fd_map, ideal_nop, 5); + return 0; +} + /* * Get the whole file as a programming convenience in order to avoid * malloc+lseek+read+free of many pieces. If successful, then mmap @@ -301,7 +329,11 @@ do_file(char const *const fname) w2(ehdr->e_machine), fname); fail_file(); break; - case EM_386: reltype = R_386_32; break; + case EM_386: + reltype = R_386_32; + make_nop = make_nop_x86; + ideal_nop = ideal_nop5_x86_32; + break; case EM_ARM: reltype = R_ARM_ABS32; altmcount = "__gnu_mcount_nc"; break; @@ -312,7 +344,11 @@ do_file(char const *const fname) case EM_S390: /* reltype: e_class */ gpfx = '_'; break; case EM_SH: reltype = R_SH_DIR32; break; case EM_SPARCV9: reltype = R_SPARC_64; gpfx = '_'; break; - case EM_X86_64: reltype = R_X86_64_64; break; + case EM_X86_64: + make_nop = make_nop_x86; + ideal_nop = ideal_nop5_x86_64; + reltype = R_X86_64_64; + break; } /* end switch */ switch (ehdr->e_ident[EI_CLASS]) { diff --git a/scripts/recordmcount.h b/scripts/recordmcount.h index 7f8d5c4..657dbed 100644 --- a/scripts/recordmcount.h +++ b/scripts/recordmcount.h @@ -23,6 +23,7 @@ #undef fn_is_fake_mcount #undef MIPS_is_fake_mcount #undef sift_rel_mcount +#undef nop_mcount #undef find_secsym_ndx #undef __has_rel_mcount #undef has_rel_mcount @@ -49,6 +50,7 @@ #ifdef RECORD_MCOUNT_64 # define append_func append64 # define sift_rel_mcount sift64_rel_mcount +# define nop_mcount nop_mcount_64 # define find_secsym_ndx find64_secsym_ndx # define __has_rel_mcount __has64_rel_mcount # define has_rel_mcount has64_rel_mcount @@ -77,6 +79,7 @@ #else # define append_func append32 # define sift_rel_mcount sift32_rel_mcount +# define nop_mcount nop_mcount_32 # define find_secsym_ndx find32_secsym_ndx # define __has_rel_mcount __has32_rel_mcount # define has_rel_mcount has32_rel_mcount @@ -304,6 +307,70 @@ static uint_t *sift_rel_mcount(uint_t *mlocp, return mlocp; } +/* + * Read the relocation table again, but this time its called on sections + * that are not going to be traced. The mcount calls here will be converted + * into nops. + */ +static void nop_mcount(Elf_Shdr const *const relhdr, + Elf_Ehdr const *const ehdr) +{ + Elf_Shdr *const shdr0 = (Elf_Shdr *)(_w(ehdr->e_shoff) + + (void *)ehdr); + unsigned const symsec_sh_link = w(relhdr->sh_link); + Elf_Shdr const *const symsec = &shdr0[symsec_sh_link]; + Elf_Sym const *const sym0 = (Elf_Sym const *)(_w(symsec->sh_offset) + + (void *)ehdr); + + Elf_Shdr const *const strsec = &shdr0[w(symsec->sh_link)]; + char const *const str0 = (char const *)(_w(strsec->sh_offset) + + (void *)ehdr); + + Elf_Rel const *const rel0 = (Elf_Rel const *)(_w(relhdr->sh_offset) + + (void *)ehdr); + unsigned rel_entsize = _w(relhdr->sh_entsize); + unsigned const nrel = _w(relhdr->sh_size) / rel_entsize; + Elf_Rel const *relp = rel0; + + Elf_Shdr const *const shdr = &shdr0[w(relhdr->sh_info)]; + + unsigned mcountsym = 0; + unsigned t; + + for (t = nrel; t; --t) { + int ret = -1; + + if (!mcountsym) { + Elf_Sym const *const symp = + &sym0[Elf_r_sym(relp)]; + char const *symname = &str0[w(symp->st_name)]; + char const *mcount = gpfx == '_' ? "_mcount" : "mcount"; + + if (symname[0] == '.') + ++symname; /* ppc64 hack */ + if (strcmp(mcount, symname) == 0 || + (altmcount && strcmp(altmcount, symname) == 0)) + mcountsym = Elf_r_sym(relp); + } + + if (mcountsym == Elf_r_sym(relp) && !is_fake_mcount(relp)) + ret = make_nop((void *)ehdr, shdr->sh_offset + relp->r_offset); + + /* + * If we successfully removed the mcount, mark the relocation + * as a nop (don't do anything with it). + */ + if (!ret) { + Elf_Rel rel; + rel = *(Elf_Rel *)relp; + Elf_r_info(&rel, Elf_r_sym(relp), rel_type_nop); + ulseek(fd_map, (void *)relp - (void *)ehdr, SEEK_SET); + uwrite(fd_map, &rel, sizeof(rel)); + } + relp = (Elf_Rel const *)(rel_entsize + (void *)relp); + } +} + /* * Find a symbol in the given section, to be used as the base for relocating @@ -360,8 +427,7 @@ __has_rel_mcount(Elf_Shdr const *const relhdr, /* is SHT_REL or SHT_RELA */ succeed_file(); } if (w(txthdr->sh_type) != SHT_PROGBITS || - !(w(txthdr->sh_flags) & SHF_EXECINSTR) || - !is_mcounted_section_name(txtname)) + !(w(txthdr->sh_flags) & SHF_EXECINSTR)) return NULL; return txtname; } @@ -384,9 +450,11 @@ static unsigned tot_relsize(Elf_Shdr const *const shdr0, { unsigned totrelsz = 0; Elf_Shdr const *shdrp = shdr0; + char const *txtname; for (; nhdr; --nhdr, ++shdrp) { - if (has_rel_mcount(shdrp, shdr0, shstrtab, fname)) + txtname = has_rel_mcount(shdrp, shdr0, shstrtab, fname); + if (txtname && is_mcounted_section_name(txtname)) totrelsz += _w(shdrp->sh_size); } return totrelsz; @@ -422,7 +490,7 @@ do_func(Elf_Ehdr *const ehdr, char const *const fname, unsigned const reltype) for (relhdr = shdr0, k = nhdr; k; --k, ++relhdr) { char const *const txtname = has_rel_mcount(relhdr, shdr0, shstrtab, fname); - if (txtname) { + if (txtname && is_mcounted_section_name(txtname)) { uint_t recval = 0; unsigned const recsym = find_secsym_ndx( w(relhdr->sh_info), txtname, &recval, @@ -433,6 +501,12 @@ do_func(Elf_Ehdr *const ehdr, char const *const fname, unsigned const reltype) mlocp = sift_rel_mcount(mlocp, (void *)mlocp - (void *)mloc0, &mrelp, relhdr, ehdr, recsym, recval, reltype); + } else if (make_nop && txtname) { + /* + * This section is ignored by ftrace, but still + * has mcount calls. Convert them to nops now. + */ + nop_mcount(relhdr, ehdr); } } if (mloc0 != mlocp) { -- cgit v1.1 From dfad3d598c4bbbaf137588e22bac1ce624529f7e Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Tue, 12 Apr 2011 18:53:25 -0400 Subject: ftrace/recordmcount: Add warning logic to warn on mcount not recorded There's some sections that should not have mcount recorded and should not have modifications to the that code. But currently they waste some time by calling mcount anyway (which simply returns). As the real answer should be to either whitelist the section or have gcc ignore it fully. This change adds a option to recordmcount to warn when it finds a section that is ignored by ftrace but still contains mcount callers. This is not on by default as developers may not know if the section should be completely ignored or added to the whitelist. Cc: John Reiser Link: http://lkml.kernel.org/r/20110421023738.476989377@goodmis.org Signed-off-by: Steven Rostedt --- scripts/recordmcount.c | 32 ++++++++++++++++++++++++-------- scripts/recordmcount.h | 22 +++++++++++++++++----- 2 files changed, 41 insertions(+), 13 deletions(-) (limited to 'scripts') diff --git a/scripts/recordmcount.c b/scripts/recordmcount.c index 78054a4..0e18975 100644 --- a/scripts/recordmcount.c +++ b/scripts/recordmcount.c @@ -24,6 +24,7 @@ #include #include #include +#include #include #include #include @@ -39,6 +40,7 @@ static char gpfx; /* prefix for global symbol name (sometimes '_') */ static struct stat sb; /* Remember .st_size, etc. */ static jmp_buf jmpenv; /* setjmp/longjmp per-file error escape */ static const char *altmcount; /* alternate mcount symbol name */ +static int warn_on_notrace_sect; /* warn when section has mcount not being recorded */ /* setjmp() return values */ enum { @@ -397,19 +399,33 @@ do_file(char const *const fname) } int -main(int argc, char const *argv[]) +main(int argc, char *argv[]) { const char ftrace[] = "/ftrace.o"; int ftrace_size = sizeof(ftrace) - 1; int n_error = 0; /* gcc-4.3.0 false positive complaint */ + int c; + int i; - if (argc <= 1) { - fprintf(stderr, "usage: recordmcount file.o...\n"); + while ((c = getopt(argc, argv, "w")) >= 0) { + switch (c) { + case 'w': + warn_on_notrace_sect = 1; + break; + default: + fprintf(stderr, "usage: recordmcount [-w] file.o...\n"); + return 0; + } + } + + if ((argc - optind) < 1) { + fprintf(stderr, "usage: recordmcount [-w] file.o...\n"); return 0; } /* Process each file in turn, allowing deep failure. */ - for (--argc, ++argv; argc > 0; --argc, ++argv) { + for (i = optind; i < argc; i++) { + char *file = argv[i]; int const sjval = setjmp(jmpenv); int len; @@ -418,14 +434,14 @@ main(int argc, char const *argv[]) * function but does not call it. Since ftrace.o should * not be traced anyway, we just skip it. */ - len = strlen(argv[0]); + len = strlen(file); if (len >= ftrace_size && - strcmp(argv[0] + (len - ftrace_size), ftrace) == 0) + strcmp(file + (len - ftrace_size), ftrace) == 0) continue; switch (sjval) { default: - fprintf(stderr, "internal error: %s\n", argv[0]); + fprintf(stderr, "internal error: %s\n", file); exit(1); break; case SJ_SETJMP: /* normal sequence */ @@ -433,7 +449,7 @@ main(int argc, char const *argv[]) fd_map = -1; ehdr_curr = NULL; mmap_failed = 1; - do_file(argv[0]); + do_file(file); break; case SJ_FAIL: /* error in do_file or below */ ++n_error; diff --git a/scripts/recordmcount.h b/scripts/recordmcount.h index 657dbed..22033d5 100644 --- a/scripts/recordmcount.h +++ b/scripts/recordmcount.h @@ -313,7 +313,8 @@ static uint_t *sift_rel_mcount(uint_t *mlocp, * into nops. */ static void nop_mcount(Elf_Shdr const *const relhdr, - Elf_Ehdr const *const ehdr) + Elf_Ehdr const *const ehdr, + const char *const txtname) { Elf_Shdr *const shdr0 = (Elf_Shdr *)(_w(ehdr->e_shoff) + (void *)ehdr); @@ -336,6 +337,7 @@ static void nop_mcount(Elf_Shdr const *const relhdr, unsigned mcountsym = 0; unsigned t; + int once = 0; for (t = nrel; t; --t) { int ret = -1; @@ -353,8 +355,18 @@ static void nop_mcount(Elf_Shdr const *const relhdr, mcountsym = Elf_r_sym(relp); } - if (mcountsym == Elf_r_sym(relp) && !is_fake_mcount(relp)) - ret = make_nop((void *)ehdr, shdr->sh_offset + relp->r_offset); + if (mcountsym == Elf_r_sym(relp) && !is_fake_mcount(relp)) { + if (make_nop) + ret = make_nop((void *)ehdr, shdr->sh_offset + relp->r_offset); + if (warn_on_notrace_sect && !once) { + printf("Section %s has mcount callers being ignored\n", + txtname); + once = 1; + /* just warn? */ + if (!make_nop) + return; + } + } /* * If we successfully removed the mcount, mark the relocation @@ -501,12 +513,12 @@ do_func(Elf_Ehdr *const ehdr, char const *const fname, unsigned const reltype) mlocp = sift_rel_mcount(mlocp, (void *)mlocp - (void *)mloc0, &mrelp, relhdr, ehdr, recsym, recval, reltype); - } else if (make_nop && txtname) { + } else if (txtname && (warn_on_notrace_sect || make_nop)) { /* * This section is ignored by ftrace, but still * has mcount calls. Convert them to nops now. */ - nop_mcount(relhdr, ehdr); + nop_mcount(relhdr, ehdr, txtname); } } if (mloc0 != mlocp) { -- cgit v1.1 From 85356f802225fedeee8c3e65bdd93b263ace0a8b Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Tue, 12 Apr 2011 18:59:10 -0400 Subject: kbuild/recordmcount: Add RECORDMCOUNT_WARN to warn about mcount callers When mcount is called in a section that ftrace will not modify it into a nop, we want to warn about this. But not warn about this always. Now if the user builds the kernel with the option RECORDMCOUNT_WARN=1 then the build will warn about mcount callers that are ignored and will just waste execution time. Acked-by: Michal Marek Cc: linux-kbuild@vger.kernel.org Link: http://lkml.kernel.org/r/20110421023738.714956282@goodmis.org Signed-off-by: Steven Rostedt --- scripts/Makefile.build | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'scripts') diff --git a/scripts/Makefile.build b/scripts/Makefile.build index d5f925a..fdca952 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -244,13 +244,16 @@ endif ifdef CONFIG_FTRACE_MCOUNT_RECORD ifdef BUILD_C_RECORDMCOUNT +ifeq ("$(origin RECORDMCOUNT_WARN)", "command line") + RECORDMCOUNT_FLAGS = -w +endif # Due to recursion, we must skip empty.o. # The empty.o file is created in the make process in order to determine # the target endianness and word size. It is made before all other C # files, including recordmcount. sub_cmd_record_mcount = \ if [ $(@) != "scripts/mod/empty.o" ]; then \ - $(objtree)/scripts/recordmcount "$(@)"; \ + $(objtree)/scripts/recordmcount $(RECORDMCOUNT_FLAGS) "$(@)"; \ fi; else sub_cmd_record_mcount = set -e ; perl $(srctree)/scripts/recordmcount.pl "$(ARCH)" \ -- cgit v1.1 From 37762cb9977626343b3cd1aab9146313c94748c2 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 20 Apr 2011 20:47:34 -0400 Subject: ftrace/recordmcount: Remove duplicate code to find mcount symbol The code in sift_rel_mcount() and nop_mcount() to get the mcount symbol number is identical. Replace the two locations with a call to a function that does the work. Cc: John Reiser Link: http://lkml.kernel.org/r/20110421023739.488093407@goodmis.org Signed-off-by: Steven Rostedt --- scripts/recordmcount.h | 51 ++++++++++++++++++++++++++------------------------ 1 file changed, 27 insertions(+), 24 deletions(-) (limited to 'scripts') diff --git a/scripts/recordmcount.h b/scripts/recordmcount.h index 22033d5..deb6a51 100644 --- a/scripts/recordmcount.h +++ b/scripts/recordmcount.h @@ -28,6 +28,7 @@ #undef __has_rel_mcount #undef has_rel_mcount #undef tot_relsize +#undef get_mcountsym #undef do_func #undef Elf_Addr #undef Elf_Ehdr @@ -56,6 +57,7 @@ # define has_rel_mcount has64_rel_mcount # define tot_relsize tot64_relsize # define do_func do64 +# define get_mcountsym get_mcountsym_64 # define is_fake_mcount is_fake_mcount64 # define fn_is_fake_mcount fn_is_fake_mcount64 # define MIPS_is_fake_mcount MIPS64_is_fake_mcount @@ -85,6 +87,7 @@ # define has_rel_mcount has32_rel_mcount # define tot_relsize tot32_relsize # define do_func do32 +# define get_mcountsym get_mcountsym_32 # define is_fake_mcount is_fake_mcount32 # define fn_is_fake_mcount fn_is_fake_mcount32 # define MIPS_is_fake_mcount MIPS32_is_fake_mcount @@ -237,6 +240,26 @@ static void append_func(Elf_Ehdr *const ehdr, uwrite(fd_map, ehdr, sizeof(*ehdr)); } +static unsigned get_mcountsym(Elf_Sym const *const sym0, + Elf_Rel const *relp, + char const *const str0) +{ + unsigned mcountsym = 0; + + Elf_Sym const *const symp = + &sym0[Elf_r_sym(relp)]; + char const *symname = &str0[w(symp->st_name)]; + char const *mcount = gpfx == '_' ? "_mcount" : "mcount"; + + if (symname[0] == '.') + ++symname; /* ppc64 hack */ + if (strcmp(mcount, symname) == 0 || + (altmcount && strcmp(altmcount, symname) == 0)) + mcountsym = Elf_r_sym(relp); + + return mcountsym; +} + /* * Look at the relocations in order to find the calls to mcount. * Accumulate the section offsets that are found, and their relocation info, @@ -274,18 +297,8 @@ static uint_t *sift_rel_mcount(uint_t *mlocp, unsigned t; for (t = nrel; t; --t) { - if (!mcountsym) { - Elf_Sym const *const symp = - &sym0[Elf_r_sym(relp)]; - char const *symname = &str0[w(symp->st_name)]; - char const *mcount = gpfx == '_' ? "_mcount" : "mcount"; - - if (symname[0] == '.') - ++symname; /* ppc64 hack */ - if (strcmp(mcount, symname) == 0 || - (altmcount && strcmp(altmcount, symname) == 0)) - mcountsym = Elf_r_sym(relp); - } + if (!mcountsym) + mcountsym = get_mcountsym(sym0, relp, str0); if (mcountsym == Elf_r_sym(relp) && !is_fake_mcount(relp)) { uint_t const addend = _w(_w(relp->r_offset) - recval); @@ -342,18 +355,8 @@ static void nop_mcount(Elf_Shdr const *const relhdr, for (t = nrel; t; --t) { int ret = -1; - if (!mcountsym) { - Elf_Sym const *const symp = - &sym0[Elf_r_sym(relp)]; - char const *symname = &str0[w(symp->st_name)]; - char const *mcount = gpfx == '_' ? "_mcount" : "mcount"; - - if (symname[0] == '.') - ++symname; /* ppc64 hack */ - if (strcmp(mcount, symname) == 0 || - (altmcount && strcmp(altmcount, symname) == 0)) - mcountsym = Elf_r_sym(relp); - } + if (!mcountsym) + mcountsym = get_mcountsym(sym0, relp, str0); if (mcountsym == Elf_r_sym(relp) && !is_fake_mcount(relp)) { if (make_nop) -- cgit v1.1 From 41b402a201a12efdff4acc990e023a89a409cd41 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 20 Apr 2011 21:13:06 -0400 Subject: ftrace/recordmcount: Add helper function get_sym_str_and_relp() The code to get the symbol, string, and relp pointers in the two functions sift_rel_mcount() and nop_mcount() are identical and also non-trivial. Moving this duplicate code into a single helper function makes the code easier to read and more maintainable. Cc: John Reiser Link: http://lkml.kernel.org/r/20110421023739.723658553@goodmis.org Signed-off-by: Steven Rostedt --- scripts/recordmcount.h | 67 ++++++++++++++++++++++++++++---------------------- 1 file changed, 37 insertions(+), 30 deletions(-) (limited to 'scripts') diff --git a/scripts/recordmcount.h b/scripts/recordmcount.h index deb6a51..3c00fab 100644 --- a/scripts/recordmcount.h +++ b/scripts/recordmcount.h @@ -29,6 +29,7 @@ #undef has_rel_mcount #undef tot_relsize #undef get_mcountsym +#undef get_sym_str_and_relp #undef do_func #undef Elf_Addr #undef Elf_Ehdr @@ -56,6 +57,7 @@ # define __has_rel_mcount __has64_rel_mcount # define has_rel_mcount has64_rel_mcount # define tot_relsize tot64_relsize +# define get_sym_str_and_relp get_sym_str_and_relp_64 # define do_func do64 # define get_mcountsym get_mcountsym_64 # define is_fake_mcount is_fake_mcount64 @@ -86,6 +88,7 @@ # define __has_rel_mcount __has32_rel_mcount # define has_rel_mcount has32_rel_mcount # define tot_relsize tot32_relsize +# define get_sym_str_and_relp get_sym_str_and_relp_32 # define do_func do32 # define get_mcountsym get_mcountsym_32 # define is_fake_mcount is_fake_mcount32 @@ -260,6 +263,29 @@ static unsigned get_mcountsym(Elf_Sym const *const sym0, return mcountsym; } +static void get_sym_str_and_relp(Elf_Shdr const *const relhdr, + Elf_Ehdr const *const ehdr, + Elf_Sym const **sym0, + char const **str0, + Elf_Rel const **relp) +{ + Elf_Shdr *const shdr0 = (Elf_Shdr *)(_w(ehdr->e_shoff) + + (void *)ehdr); + unsigned const symsec_sh_link = w(relhdr->sh_link); + Elf_Shdr const *const symsec = &shdr0[symsec_sh_link]; + Elf_Shdr const *const strsec = &shdr0[w(symsec->sh_link)]; + Elf_Rel const *const rel0 = (Elf_Rel const *)(_w(relhdr->sh_offset) + + (void *)ehdr); + + *sym0 = (Elf_Sym const *)(_w(symsec->sh_offset) + + (void *)ehdr); + + *str0 = (char const *)(_w(strsec->sh_offset) + + (void *)ehdr); + + *relp = rel0; +} + /* * Look at the relocations in order to find the calls to mcount. * Accumulate the section offsets that are found, and their relocation info, @@ -276,26 +302,16 @@ static uint_t *sift_rel_mcount(uint_t *mlocp, { uint_t *const mloc0 = mlocp; Elf_Rel *mrelp = *mrelpp; - Elf_Shdr *const shdr0 = (Elf_Shdr *)(_w(ehdr->e_shoff) - + (void *)ehdr); - unsigned const symsec_sh_link = w(relhdr->sh_link); - Elf_Shdr const *const symsec = &shdr0[symsec_sh_link]; - Elf_Sym const *const sym0 = (Elf_Sym const *)(_w(symsec->sh_offset) - + (void *)ehdr); - - Elf_Shdr const *const strsec = &shdr0[w(symsec->sh_link)]; - char const *const str0 = (char const *)(_w(strsec->sh_offset) - + (void *)ehdr); - - Elf_Rel const *const rel0 = (Elf_Rel const *)(_w(relhdr->sh_offset) - + (void *)ehdr); + Elf_Sym const *sym0; + char const *str0; + Elf_Rel const *relp; unsigned rel_entsize = _w(relhdr->sh_entsize); unsigned const nrel = _w(relhdr->sh_size) / rel_entsize; - Elf_Rel const *relp = rel0; - unsigned mcountsym = 0; unsigned t; + get_sym_str_and_relp(relhdr, ehdr, &sym0, &str0, &relp); + for (t = nrel; t; --t) { if (!mcountsym) mcountsym = get_mcountsym(sym0, relp, str0); @@ -331,27 +347,18 @@ static void nop_mcount(Elf_Shdr const *const relhdr, { Elf_Shdr *const shdr0 = (Elf_Shdr *)(_w(ehdr->e_shoff) + (void *)ehdr); - unsigned const symsec_sh_link = w(relhdr->sh_link); - Elf_Shdr const *const symsec = &shdr0[symsec_sh_link]; - Elf_Sym const *const sym0 = (Elf_Sym const *)(_w(symsec->sh_offset) - + (void *)ehdr); - - Elf_Shdr const *const strsec = &shdr0[w(symsec->sh_link)]; - char const *const str0 = (char const *)(_w(strsec->sh_offset) - + (void *)ehdr); - - Elf_Rel const *const rel0 = (Elf_Rel const *)(_w(relhdr->sh_offset) - + (void *)ehdr); + Elf_Sym const *sym0; + char const *str0; + Elf_Rel const *relp; + Elf_Shdr const *const shdr = &shdr0[w(relhdr->sh_info)]; unsigned rel_entsize = _w(relhdr->sh_entsize); unsigned const nrel = _w(relhdr->sh_size) / rel_entsize; - Elf_Rel const *relp = rel0; - - Elf_Shdr const *const shdr = &shdr0[w(relhdr->sh_info)]; - unsigned mcountsym = 0; unsigned t; int once = 0; + get_sym_str_and_relp(relhdr, ehdr, &sym0, &str0, &relp); + for (t = nrel; t; --t) { int ret = -1; -- cgit v1.1 From 07d8b595f367f4604e6027ad4cba33cbe3f55e10 Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Tue, 10 May 2011 10:10:40 +0200 Subject: ftrace/recordmcount: mcount address adjustment Introduce mcount_adjust{,_32,_64} to the C implementation of recordmcount analog to $mcount_adjust in the perl script. The adjustment is added to the address of the relocations against the mcount symbol. If this adjustment is done by recordmcount at compile time the ftrace_call_adjust function can be turned into a nop. Cc: John Reiser Signed-off-by: Martin Schwidefsky Signed-off-by: Steven Rostedt --- scripts/recordmcount.h | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) (limited to 'scripts') diff --git a/scripts/recordmcount.h b/scripts/recordmcount.h index 3c00fab..4be6036 100644 --- a/scripts/recordmcount.h +++ b/scripts/recordmcount.h @@ -22,6 +22,7 @@ #undef is_fake_mcount #undef fn_is_fake_mcount #undef MIPS_is_fake_mcount +#undef mcount_adjust #undef sift_rel_mcount #undef nop_mcount #undef find_secsym_ndx @@ -63,6 +64,7 @@ # define is_fake_mcount is_fake_mcount64 # define fn_is_fake_mcount fn_is_fake_mcount64 # define MIPS_is_fake_mcount MIPS64_is_fake_mcount +# define mcount_adjust mcount_adjust_64 # define Elf_Addr Elf64_Addr # define Elf_Ehdr Elf64_Ehdr # define Elf_Shdr Elf64_Shdr @@ -94,6 +96,7 @@ # define is_fake_mcount is_fake_mcount32 # define fn_is_fake_mcount fn_is_fake_mcount32 # define MIPS_is_fake_mcount MIPS32_is_fake_mcount +# define mcount_adjust mcount_adjust_32 # define Elf_Addr Elf32_Addr # define Elf_Ehdr Elf32_Ehdr # define Elf_Shdr Elf32_Shdr @@ -132,6 +135,8 @@ static void fn_ELF_R_INFO(Elf_Rel *const rp, unsigned sym, unsigned type) } static void (*Elf_r_info)(Elf_Rel *const rp, unsigned sym, unsigned type) = fn_ELF_R_INFO; +static int mcount_adjust = 0; + /* * MIPS mcount long call has 2 _mcount symbols, only the position of the 1st * _mcount symbol is needed for dynamic function tracer, with it, to disable @@ -317,8 +322,8 @@ static uint_t *sift_rel_mcount(uint_t *mlocp, mcountsym = get_mcountsym(sym0, relp, str0); if (mcountsym == Elf_r_sym(relp) && !is_fake_mcount(relp)) { - uint_t const addend = _w(_w(relp->r_offset) - recval); - + uint_t const addend = + _w(_w(relp->r_offset) - recval + mcount_adjust); mrelp->r_offset = _w(offbase + ((void *)mlocp - (void *)mloc0)); Elf_r_info(mrelp, recsym, reltype); -- cgit v1.1 From 521ccb5c4aece609311bfa7157910a8f0c942af5 Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Tue, 10 May 2011 10:10:41 +0200 Subject: ftrace/x86: mcount offset calculation Do the mcount offset adjustment in the recordmcount.pl/recordmcount.[ch] at compile time and not in ftrace_call_adjust at run time. Signed-off-by: Martin Schwidefsky Signed-off-by: Steven Rostedt --- scripts/recordmcount.c | 2 ++ scripts/recordmcount.pl | 2 ++ 2 files changed, 4 insertions(+) (limited to 'scripts') diff --git a/scripts/recordmcount.c b/scripts/recordmcount.c index 0e18975..7648a5d 100644 --- a/scripts/recordmcount.c +++ b/scripts/recordmcount.c @@ -335,6 +335,7 @@ do_file(char const *const fname) reltype = R_386_32; make_nop = make_nop_x86; ideal_nop = ideal_nop5_x86_32; + mcount_adjust_32 = -1; break; case EM_ARM: reltype = R_ARM_ABS32; altmcount = "__gnu_mcount_nc"; @@ -350,6 +351,7 @@ do_file(char const *const fname) make_nop = make_nop_x86; ideal_nop = ideal_nop5_x86_64; reltype = R_X86_64_64; + mcount_adjust_64 = -1; break; } /* end switch */ diff --git a/scripts/recordmcount.pl b/scripts/recordmcount.pl index a871cd4..414e7f5 100755 --- a/scripts/recordmcount.pl +++ b/scripts/recordmcount.pl @@ -223,6 +223,7 @@ if ($arch eq "x86_64") { $mcount_regex = "^\\s*([0-9a-fA-F]+):.*\\smcount([+-]0x[0-9a-zA-Z]+)?\$"; $type = ".quad"; $alignment = 8; + $mcount_adjust = -1; # force flags for this arch $ld .= " -m elf_x86_64"; @@ -232,6 +233,7 @@ if ($arch eq "x86_64") { } elsif ($arch eq "i386") { $alignment = 4; + $mcount_adjust = -1; # force flags for this arch $ld .= " -m elf_i386"; -- cgit v1.1 From f29638868280534ed7e2fdd93b31557232597940 Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Tue, 10 May 2011 10:10:43 +0200 Subject: ftrace/s390: mcount offset calculation Do the mcount offset adjustment in the recordmcount.pl/recordmcount.[ch] at compile time and not in ftrace_call_adjust at run time. Signed-off-by: Martin Schwidefsky Signed-off-by: Steven Rostedt --- scripts/recordmcount.c | 8 ++++++-- scripts/recordmcount.pl | 2 ++ 2 files changed, 8 insertions(+), 2 deletions(-) (limited to 'scripts') diff --git a/scripts/recordmcount.c b/scripts/recordmcount.c index 7648a5d..ee52cb8 100644 --- a/scripts/recordmcount.c +++ b/scripts/recordmcount.c @@ -368,8 +368,10 @@ do_file(char const *const fname) "unrecognized ET_REL file: %s\n", fname); fail_file(); } - if (w2(ehdr->e_machine) == EM_S390) + if (w2(ehdr->e_machine) == EM_S390) { reltype = R_390_32; + mcount_adjust_32 = -4; + } if (w2(ehdr->e_machine) == EM_MIPS) { reltype = R_MIPS_32; is_fake_mcount32 = MIPS32_is_fake_mcount; @@ -384,8 +386,10 @@ do_file(char const *const fname) "unrecognized ET_REL file: %s\n", fname); fail_file(); } - if (w2(ghdr->e_machine) == EM_S390) + if (w2(ghdr->e_machine) == EM_S390) { reltype = R_390_64; + mcount_adjust_64 = -8; + } if (w2(ghdr->e_machine) == EM_MIPS) { reltype = R_MIPS_64; Elf64_r_sym = MIPS64_r_sym; diff --git a/scripts/recordmcount.pl b/scripts/recordmcount.pl index 414e7f5..858966a 100755 --- a/scripts/recordmcount.pl +++ b/scripts/recordmcount.pl @@ -243,12 +243,14 @@ if ($arch eq "x86_64") { } elsif ($arch eq "s390" && $bits == 32) { $mcount_regex = "^\\s*([0-9a-fA-F]+):\\s*R_390_32\\s+_mcount\$"; + $mcount_adjust = -4; $alignment = 4; $ld .= " -m elf_s390"; $cc .= " -m31"; } elsif ($arch eq "s390" && $bits == 64) { $mcount_regex = "^\\s*([0-9a-fA-F]+):\\s*R_390_(PC|PLT)32DBL\\s+_mcount\\+0x2\$"; + $mcount_adjust = -8; $alignment = 8; $type = ".quad"; $ld .= " -m elf64_s390"; -- cgit v1.1 From d6971822c288ce5547190c6f812cc978d6520777 Mon Sep 17 00:00:00 2001 From: Michal Marek Date: Tue, 17 May 2011 15:36:46 +0200 Subject: ftrace/kbuild: Add recordmcount files to force full build Modifications to recordmcount must be performed on all object files to stay consistent with what the kernel code may expect. Add the recordmcount files to the main dependencies to make sure any change to them causes a full recompile. Signed-off-by: Michal Marek Link: http://lkml.kernel.org/r/20110517133646.GP13293@sepie.suse.cz Signed-off-by: Steven Rostedt --- scripts/Makefile.build | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'scripts') diff --git a/scripts/Makefile.build b/scripts/Makefile.build index fdca952..6165622 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -255,6 +255,8 @@ sub_cmd_record_mcount = \ if [ $(@) != "scripts/mod/empty.o" ]; then \ $(objtree)/scripts/recordmcount $(RECORDMCOUNT_FLAGS) "$(@)"; \ fi; +recordmcount_source := $(srctree)/scripts/recordmcount.c \ + $(srctree)/scripts/recordmcount.h else sub_cmd_record_mcount = set -e ; perl $(srctree)/scripts/recordmcount.pl "$(ARCH)" \ "$(if $(CONFIG_CPU_BIG_ENDIAN),big,little)" \ @@ -262,6 +264,7 @@ sub_cmd_record_mcount = set -e ; perl $(srctree)/scripts/recordmcount.pl "$(ARCH "$(OBJDUMP)" "$(OBJCOPY)" "$(CC) $(KBUILD_CFLAGS)" \ "$(LD)" "$(NM)" "$(RM)" "$(MV)" \ "$(if $(part-of-module),1,0)" "$(@)"; +recordmcount_source := $(srctree)/scripts/recordmcount.pl endif cmd_record_mcount = \ if [ "$(findstring -pg,$(_c_flags))" = "-pg" ]; then \ @@ -282,13 +285,13 @@ define rule_cc_o_c endef # Built-in and composite module parts -$(obj)/%.o: $(src)/%.c FORCE +$(obj)/%.o: $(src)/%.c $(recordmcount_source) FORCE $(call cmd,force_checksrc) $(call if_changed_rule,cc_o_c) # Single-part modules are special since we need to mark them in $(MODVERDIR) -$(single-used-m): $(obj)/%.o: $(src)/%.c FORCE +$(single-used-m): $(obj)/%.o: $(src)/%.c $(recordmcount_source) FORCE $(call cmd,force_checksrc) $(call if_changed_rule,cc_o_c) @{ echo $(@:.o=.ko); echo $@; } > $(MODVERDIR)/$(@F:.o=.mod) -- cgit v1.1