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-rw-r--r--scripts/recordmcount.c321
1 files changed, 157 insertions, 164 deletions
diff --git a/scripts/recordmcount.c b/scripts/recordmcount.c
index 8387a9bc064a..612268eabef4 100644
--- a/scripts/recordmcount.c
+++ b/scripts/recordmcount.c
@@ -27,7 +27,6 @@
#include <getopt.h>
#include <elf.h>
#include <fcntl.h>
-#include <setjmp.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
@@ -43,56 +42,37 @@ static int fd_map; /* File descriptor for file being modified. */
static int mmap_failed; /* Boolean flag. */
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 */
static void *file_map; /* pointer of the mapped file */
static void *file_end; /* pointer to the end of the mapped file */
static int file_updated; /* flag to state file was changed */
static void *file_ptr; /* current file pointer location */
+
static void *file_append; /* added to the end of the file */
static size_t file_append_size; /* how much is added to end of file */
-/* setjmp() return values */
-enum {
- SJ_SETJMP = 0, /* hardwired first return */
- SJ_FAIL,
- SJ_SUCCEED
-};
-
/* Per-file resource cleanup when multiple files. */
-static void
-cleanup(void)
+static void file_append_cleanup(void)
{
- if (!mmap_failed)
- munmap(file_map, sb.st_size);
- else
- free(file_map);
- file_map = NULL;
free(file_append);
file_append = NULL;
file_append_size = 0;
file_updated = 0;
}
-static void __attribute__((noreturn))
-fail_file(void)
+static void mmap_cleanup(void)
{
- cleanup();
- longjmp(jmpenv, SJ_FAIL);
-}
-
-static void __attribute__((noreturn))
-succeed_file(void)
-{
- cleanup();
- longjmp(jmpenv, SJ_SUCCEED);
+ if (!mmap_failed)
+ munmap(file_map, sb.st_size);
+ else
+ free(file_map);
+ file_map = NULL;
}
-/* ulseek, uread, ...: Check return value for errors. */
+/* ulseek, uwrite, ...: Check return value for errors. */
-static off_t
-ulseek(int const fd, off_t const offset, int const whence)
+static off_t ulseek(off_t const offset, int const whence)
{
switch (whence) {
case SEEK_SET:
@@ -107,24 +87,12 @@ ulseek(int const fd, off_t const offset, int const whence)
}
if (file_ptr < file_map) {
fprintf(stderr, "lseek: seek before file\n");
- fail_file();
+ return -1;
}
return file_ptr - file_map;
}
-static size_t
-uread(int const fd, void *const buf, size_t const count)
-{
- size_t const n = read(fd, buf, count);
- if (n != count) {
- perror("read");
- fail_file();
- }
- return n;
-}
-
-static size_t
-uwrite(int const fd, void const *const buf, size_t const count)
+static ssize_t uwrite(void const *const buf, size_t const count)
{
size_t cnt = count;
off_t idx = 0;
@@ -140,7 +108,9 @@ uwrite(int const fd, void const *const buf, size_t const count)
}
if (!file_append) {
perror("write");
- fail_file();
+ file_append_cleanup();
+ mmap_cleanup();
+ return -1;
}
if (file_ptr < file_end) {
cnt = file_end - file_ptr;
@@ -160,17 +130,81 @@ uwrite(int const fd, void const *const buf, size_t const count)
return count;
}
-static void *
-umalloc(size_t size)
+static void * umalloc(size_t size)
{
void *const addr = malloc(size);
if (addr == 0) {
fprintf(stderr, "malloc failed: %zu bytes\n", size);
- fail_file();
+ file_append_cleanup();
+ mmap_cleanup();
+ return NULL;
}
return addr;
}
+/*
+ * Get the whole file as a programming convenience in order to avoid
+ * malloc+lseek+read+free of many pieces. If successful, then mmap
+ * avoids copying unused pieces; else just read the whole file.
+ * Open for both read and write; new info will be appended to the file.
+ * Use MAP_PRIVATE so that a few changes to the in-memory ElfXX_Ehdr
+ * do not propagate to the file until an explicit overwrite at the last.
+ * This preserves most aspects of consistency (all except .st_size)
+ * for simultaneous readers of the file while we are appending to it.
+ * However, multiple writers still are bad. We choose not to use
+ * locking because it is expensive and the use case of kernel build
+ * makes multiple writers unlikely.
+ */
+static void *mmap_file(char const *fname)
+{
+ /* Avoid problems if early cleanup() */
+ fd_map = -1;
+ mmap_failed = 1;
+ file_map = NULL;
+ file_ptr = NULL;
+ file_updated = 0;
+ sb.st_size = 0;
+
+ fd_map = open(fname, O_RDONLY);
+ if (fd_map < 0) {
+ perror(fname);
+ return NULL;
+ }
+ if (fstat(fd_map, &sb) < 0) {
+ perror(fname);
+ goto out;
+ }
+ if (!S_ISREG(sb.st_mode)) {
+ fprintf(stderr, "not a regular file: %s\n", fname);
+ goto out;
+ }
+ file_map = mmap(0, sb.st_size, PROT_READ|PROT_WRITE, MAP_PRIVATE,
+ fd_map, 0);
+ if (file_map == MAP_FAILED) {
+ mmap_failed = 1;
+ file_map = umalloc(sb.st_size);
+ if (!file_map) {
+ perror(fname);
+ goto out;
+ }
+ if (read(fd_map, file_map, sb.st_size) != sb.st_size) {
+ perror(fname);
+ free(file_map);
+ file_map = NULL;
+ goto out;
+ }
+ } else
+ mmap_failed = 0;
+out:
+ close(fd_map);
+ fd_map = -1;
+
+ file_end = file_map + sb.st_size;
+
+ return file_map;
+}
+
+
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;
@@ -194,8 +228,10 @@ static int make_nop_x86(void *map, size_t const offset)
return -1;
/* convert to nop */
- ulseek(fd_map, offset - 1, SEEK_SET);
- uwrite(fd_map, ideal_nop, 5);
+ if (ulseek(offset - 1, SEEK_SET) < 0)
+ return -1;
+ if (uwrite(ideal_nop, 5) < 0)
+ return -1;
return 0;
}
@@ -243,10 +279,12 @@ static int make_nop_arm(void *map, size_t const offset)
return -1;
/* Convert to nop */
- ulseek(fd_map, off, SEEK_SET);
+ if (ulseek(off, SEEK_SET) < 0)
+ return -1;
do {
- uwrite(fd_map, ideal_nop, nop_size);
+ if (uwrite(ideal_nop, nop_size) < 0)
+ return -1;
} while (--cnt > 0);
return 0;
@@ -263,57 +301,20 @@ static int make_nop_arm64(void *map, size_t const offset)
return -1;
/* Convert to nop */
- ulseek(fd_map, offset, SEEK_SET);
- uwrite(fd_map, ideal_nop, 4);
+ if (ulseek(offset, SEEK_SET) < 0)
+ return -1;
+ if (uwrite(ideal_nop, 4) < 0)
+ return -1;
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
- * avoids copying unused pieces; else just read the whole file.
- * Open for both read and write; new info will be appended to the file.
- * Use MAP_PRIVATE so that a few changes to the in-memory ElfXX_Ehdr
- * do not propagate to the file until an explicit overwrite at the last.
- * This preserves most aspects of consistency (all except .st_size)
- * for simultaneous readers of the file while we are appending to it.
- * However, multiple writers still are bad. We choose not to use
- * locking because it is expensive and the use case of kernel build
- * makes multiple writers unlikely.
- */
-static void *mmap_file(char const *fname)
-{
- fd_map = open(fname, O_RDONLY);
- if (fd_map < 0 || fstat(fd_map, &sb) < 0) {
- perror(fname);
- fail_file();
- }
- if (!S_ISREG(sb.st_mode)) {
- fprintf(stderr, "not a regular file: %s\n", fname);
- fail_file();
- }
- file_map = mmap(0, sb.st_size, PROT_READ|PROT_WRITE, MAP_PRIVATE,
- fd_map, 0);
- mmap_failed = 0;
- if (file_map == MAP_FAILED) {
- mmap_failed = 1;
- file_map = umalloc(sb.st_size);
- uread(fd_map, file_map, sb.st_size);
- }
- close(fd_map);
-
- file_end = file_map + sb.st_size;
-
- return file_map;
-}
-
-static void write_file(const char *fname)
+static int write_file(const char *fname)
{
char tmp_file[strlen(fname) + 4];
size_t n;
if (!file_updated)
- return;
+ return 0;
sprintf(tmp_file, "%s.rc", fname);
@@ -325,25 +326,28 @@ static void write_file(const char *fname)
fd_map = open(tmp_file, O_WRONLY | O_TRUNC | O_CREAT, sb.st_mode);
if (fd_map < 0) {
perror(fname);
- fail_file();
+ return -1;
}
n = write(fd_map, file_map, sb.st_size);
if (n != sb.st_size) {
perror("write");
- fail_file();
+ close(fd_map);
+ return -1;
}
if (file_append_size) {
n = write(fd_map, file_append, file_append_size);
if (n != file_append_size) {
perror("write");
- fail_file();
+ close(fd_map);
+ return -1;
}
}
close(fd_map);
if (rename(tmp_file, fname) < 0) {
perror(fname);
- fail_file();
+ return -1;
}
+ return 0;
}
/* w8rev, w8nat, ...: Handle endianness. */
@@ -394,8 +398,7 @@ static uint32_t (*w)(uint32_t);
static uint32_t (*w2)(uint16_t);
/* Names of the sections that could contain calls to mcount. */
-static int
-is_mcounted_section_name(char const *const txtname)
+static int is_mcounted_section_name(char const *const txtname)
{
return strncmp(".text", txtname, 5) == 0 ||
strcmp(".init.text", txtname) == 0 ||
@@ -405,10 +408,11 @@ is_mcounted_section_name(char const *const txtname)
strcmp(".irqentry.text", txtname) == 0 ||
strcmp(".softirqentry.text", txtname) == 0 ||
strcmp(".kprobes.text", txtname) == 0 ||
- strcmp(".cpuidle.text", txtname) == 0 ||
- strcmp(".text.unlikely", txtname) == 0;
+ strcmp(".cpuidle.text", txtname) == 0;
}
+static char const *already_has_rel_mcount = "success"; /* our work here is done! */
+
/* 32 bit and 64 bit are very similar */
#include "recordmcount.h"
#define RECORD_MCOUNT_64
@@ -447,11 +451,15 @@ static void MIPS64_r_info(Elf64_Rel *const rp, unsigned sym, unsigned type)
}).r_info;
}
-static void
-do_file(char const *const fname)
+static int do_file(char const *const fname)
{
- Elf32_Ehdr *const ehdr = mmap_file(fname);
unsigned int reltype = 0;
+ Elf32_Ehdr *ehdr;
+ int rc = -1;
+
+ ehdr = mmap_file(fname);
+ if (!ehdr)
+ goto out;
w = w4nat;
w2 = w2nat;
@@ -461,8 +469,7 @@ do_file(char const *const fname)
default:
fprintf(stderr, "unrecognized ELF data encoding %d: %s\n",
ehdr->e_ident[EI_DATA], fname);
- fail_file();
- break;
+ goto out;
case ELFDATA2LSB:
if (*(unsigned char const *)&endian != 1) {
/* main() is big endian, file.o is little endian. */
@@ -490,52 +497,54 @@ do_file(char const *const fname)
push_bl_mcount_thumb = push_bl_mcount_thumb_be;
break;
} /* end switch */
- if (memcmp(ELFMAG, ehdr->e_ident, SELFMAG) != 0
- || w2(ehdr->e_type) != ET_REL
- || ehdr->e_ident[EI_VERSION] != EV_CURRENT) {
+ 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();
+ goto out;
}
- gpfx = 0;
+ gpfx = '_';
switch (w2(ehdr->e_machine)) {
default:
fprintf(stderr, "unrecognized e_machine %u %s\n",
w2(ehdr->e_machine), fname);
- fail_file();
- break;
+ goto out;
case EM_386:
reltype = R_386_32;
rel_type_nop = R_386_NONE;
make_nop = make_nop_x86;
ideal_nop = ideal_nop5_x86_32;
mcount_adjust_32 = -1;
+ gpfx = 0;
+ break;
+ case EM_ARM:
+ reltype = R_ARM_ABS32;
+ altmcount = "__gnu_mcount_nc";
+ make_nop = make_nop_arm;
+ rel_type_nop = R_ARM_NONE;
+ gpfx = 0;
break;
- case EM_ARM: reltype = R_ARM_ABS32;
- altmcount = "__gnu_mcount_nc";
- make_nop = make_nop_arm;
- rel_type_nop = R_ARM_NONE;
- break;
case EM_AARCH64:
- reltype = R_AARCH64_ABS64;
- make_nop = make_nop_arm64;
- rel_type_nop = R_AARCH64_NONE;
- ideal_nop = ideal_nop4_arm64;
- gpfx = '_';
- break;
- case EM_IA_64: reltype = R_IA64_IMM64; gpfx = '_'; break;
- case EM_MIPS: /* reltype: e_class */ gpfx = '_'; break;
- case EM_PPC: reltype = R_PPC_ADDR32; gpfx = '_'; break;
- case EM_PPC64: reltype = R_PPC64_ADDR64; gpfx = '_'; break;
- 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;
+ reltype = R_AARCH64_ABS64;
+ make_nop = make_nop_arm64;
+ rel_type_nop = R_AARCH64_NONE;
+ ideal_nop = ideal_nop4_arm64;
+ break;
+ case EM_IA_64: reltype = R_IA64_IMM64; break;
+ case EM_MIPS: /* reltype: e_class */ break;
+ case EM_PPC: reltype = R_PPC_ADDR32; break;
+ case EM_PPC64: reltype = R_PPC64_ADDR64; break;
+ case EM_S390: /* reltype: e_class */ break;
+ case EM_SH: reltype = R_SH_DIR32; gpfx = 0; break;
+ case EM_SPARCV9: reltype = R_SPARC_64; break;
case EM_X86_64:
make_nop = make_nop_x86;
ideal_nop = ideal_nop5_x86_64;
reltype = R_X86_64_64;
rel_type_nop = R_X86_64_NONE;
mcount_adjust_64 = -1;
+ gpfx = 0;
break;
} /* end switch */
@@ -543,20 +552,20 @@ do_file(char const *const fname)
default:
fprintf(stderr, "unrecognized ELF class %d %s\n",
ehdr->e_ident[EI_CLASS], fname);
- fail_file();
- break;
+ goto out;
case ELFCLASS32:
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();
+ goto out;
}
if (w2(ehdr->e_machine) == EM_MIPS) {
reltype = R_MIPS_32;
is_fake_mcount32 = MIPS32_is_fake_mcount;
}
- do32(ehdr, fname, reltype);
+ if (do32(ehdr, fname, reltype) < 0)
+ goto out;
break;
case ELFCLASS64: {
Elf64_Ehdr *const ghdr = (Elf64_Ehdr *)ehdr;
@@ -564,7 +573,7 @@ do_file(char const *const fname)
|| w2(ghdr->e_shentsize) != sizeof(Elf64_Shdr)) {
fprintf(stderr,
"unrecognized ET_REL file: %s\n", fname);
- fail_file();
+ goto out;
}
if (w2(ghdr->e_machine) == EM_S390) {
reltype = R_390_64;
@@ -576,17 +585,20 @@ do_file(char const *const fname)
Elf64_r_info = MIPS64_r_info;
is_fake_mcount64 = MIPS64_is_fake_mcount;
}
- do64(ghdr, fname, reltype);
+ if (do64(ghdr, fname, reltype) < 0)
+ goto out;
break;
}
} /* end switch */
- write_file(fname);
- cleanup();
+ rc = write_file(fname);
+out:
+ file_append_cleanup();
+ mmap_cleanup();
+ return rc;
}
-int
-main(int argc, char *argv[])
+int main(int argc, char *argv[])
{
const char ftrace[] = "/ftrace.o";
int ftrace_size = sizeof(ftrace) - 1;
@@ -613,7 +625,6 @@ main(int argc, char *argv[])
/* Process each file in turn, allowing deep failure. */
for (i = optind; i < argc; i++) {
char *file = argv[i];
- int const sjval = setjmp(jmpenv);
int len;
/*
@@ -626,28 +637,10 @@ main(int argc, char *argv[])
strcmp(file + (len - ftrace_size), ftrace) == 0)
continue;
- switch (sjval) {
- default:
- fprintf(stderr, "internal error: %s\n", file);
- exit(1);
- break;
- case SJ_SETJMP: /* normal sequence */
- /* Avoid problems if early cleanup() */
- fd_map = -1;
- mmap_failed = 1;
- file_map = NULL;
- file_ptr = NULL;
- file_updated = 0;
- do_file(file);
- break;
- case SJ_FAIL: /* error in do_file or below */
+ if (do_file(file)) {
fprintf(stderr, "%s: failed\n", file);
++n_error;
- break;
- case SJ_SUCCEED: /* premature success */
- /* do nothing */
- break;
- } /* end switch */
+ }
}
return !!n_error;
}
generated by cgit v1.2.3 (git 2.46.0) at 2025-10-31 02:47:21 +0000