From 738782294d8fc4b27a95ccd1434526787287de5c Mon Sep 17 00:00:00 2001 From: liqingqing_1229 Date: Thu, 2 Dec 2021 19:28:14 +0800 Subject: [PATCH] revert the use of sched_getaffinity [BZ #28310] (cherry picked from commit 0057d144a90d6b57f3e3ba185dfca19d1a3282d7) --- glibc.spec | 8 +- ...-use-of-sched_getaffinity-on-get_npr.patch | 206 +++++++++++++++++ linux-Simplify-get_nprocs.patch | 216 ++++++++++++++++++ misc-Add-__get_nprocs_sched.patch | 110 +++++++++ 4 files changed, 539 insertions(+), 1 deletion(-) create mode 100644 linux-Revert-the-use-of-sched_getaffinity-on-get_npr.patch create mode 100644 linux-Simplify-get_nprocs.patch create mode 100644 misc-Add-__get_nprocs_sched.patch diff --git a/glibc.spec b/glibc.spec index af2dbad..4c8bcda 100644 --- a/glibc.spec +++ b/glibc.spec @@ -65,7 +65,7 @@ ############################################################################## Name: glibc Version: 2.34 -Release: 28 +Release: 29 Summary: The GNU libc libraries License: %{all_license} URL: http://www.gnu.org/software/glibc/ @@ -134,6 +134,9 @@ Patch47: ld.so-Initialize-bootstrap_map.l_ld_readonly-BZ-2834.patch Patch48: Avoid-warning-overriding-recipe-for-.-tst-ro-dynamic.patch Patch49: posix-Fix-attribute-access-mode-on-getcwd-BZ-27476.patch Patch50: Linux-Simplify-__opensock-and-fix-race-condition-BZ-.patch +Patch51: linux-Simplify-get_nprocs.patch +Patch52: misc-Add-__get_nprocs_sched.patch +Patch53: linux-Revert-the-use-of-sched_getaffinity-on-get_npr.patch #Patch9000: turn-REP_STOSB_THRESHOLD-from-2k-to-1M.patch Patch9001: delete-no-hard-link-to-avoid-all_language-package-to.patch @@ -1331,6 +1334,9 @@ fi %endif %changelog +* Thu Dec 2 2021 Qingqing Li - 2.34-29 +- revert the use of sched_getaffinity [BZ #28310] + * Tue Nov 30 2021 Bin Wang - 2.34-28 - Linux: Simplify __opensock and fix race condition [BZ #28353] diff --git a/linux-Revert-the-use-of-sched_getaffinity-on-get_npr.patch b/linux-Revert-the-use-of-sched_getaffinity-on-get_npr.patch new file mode 100644 index 0000000..17a7a5c --- /dev/null +++ b/linux-Revert-the-use-of-sched_getaffinity-on-get_npr.patch @@ -0,0 +1,206 @@ +From 342298278eabc75baabcaced110a11a02c3d3580 Mon Sep 17 00:00:00 2001 +From: Adhemerval Zanella +Date: Mon, 6 Sep 2021 14:19:51 -0300 +Subject: [PATCH] linux: Revert the use of sched_getaffinity on get_nproc (BZ + #28310) + +The use of sched_getaffinity on get_nproc and +sysconf (_SC_NPROCESSORS_ONLN) done in 903bc7dcc2acafc40 (BZ #27645) +breaks the top command in common hypervisor configurations and also +other monitoring tools. + +The main issue using sched_getaffinity changed the symbols semantic +from system-wide scope of online CPUs to per-process one (which can +be changed with kernel cpusets or book parameters in VM). + +This patch reverts mostly of the 903bc7dcc2acafc40, with the +exceptions: + + * No more cached values and atomic updates, since they are inherent + racy. + + * No /proc/cpuinfo fallback, since /proc/stat is already used and + it would require to revert more arch-specific code. + + * The alloca is replace with a static buffer of 1024 bytes. + +So the implementation first consult the sysfs, and fallbacks to procfs. + +Checked on x86_64-linux-gnu. + +Reviewed-by: Florian Weimer +--- + sysdeps/unix/sysv/linux/getsysstats.c | 139 ++++++++++++++++++++++++++++++++-- + 1 file changed, 134 insertions(+), 5 deletions(-) + +diff --git a/sysdeps/unix/sysv/linux/getsysstats.c b/sysdeps/unix/sysv/linux/getsysstats.c +index 1e3d886..15ad91c 100644 +--- a/sysdeps/unix/sysv/linux/getsysstats.c ++++ b/sysdeps/unix/sysv/linux/getsysstats.c +@@ -17,6 +17,8 @@ + . */ + + #include ++#include ++#include + #include + #include + #include +@@ -29,7 +31,7 @@ + #include + + int +-__get_nprocs (void) ++__get_nprocs_sched (void) + { + enum + { +@@ -52,14 +54,141 @@ __get_nprocs (void) + atomics are needed). */ + return 2; + } +-libc_hidden_def (__get_nprocs) +-weak_alias (__get_nprocs, get_nprocs) ++ ++static char * ++next_line (int fd, char *const buffer, char **cp, char **re, ++ char *const buffer_end) ++{ ++ char *res = *cp; ++ char *nl = memchr (*cp, '\n', *re - *cp); ++ if (nl == NULL) ++ { ++ if (*cp != buffer) ++ { ++ if (*re == buffer_end) ++ { ++ memmove (buffer, *cp, *re - *cp); ++ *re = buffer + (*re - *cp); ++ *cp = buffer; ++ ++ ssize_t n = __read_nocancel (fd, *re, buffer_end - *re); ++ if (n < 0) ++ return NULL; ++ ++ *re += n; ++ ++ nl = memchr (*cp, '\n', *re - *cp); ++ while (nl == NULL && *re == buffer_end) ++ { ++ /* Truncate too long lines. */ ++ *re = buffer + 3 * (buffer_end - buffer) / 4; ++ n = __read_nocancel (fd, *re, buffer_end - *re); ++ if (n < 0) ++ return NULL; ++ ++ nl = memchr (*re, '\n', n); ++ **re = '\n'; ++ *re += n; ++ } ++ } ++ else ++ nl = memchr (*cp, '\n', *re - *cp); ++ ++ res = *cp; ++ } ++ ++ if (nl == NULL) ++ nl = *re - 1; ++ } ++ ++ *cp = nl + 1; ++ assert (*cp <= *re); ++ ++ return res == *re ? NULL : res; ++} ++ + + int +-__get_nprocs_sched (void) ++__get_nprocs (void) + { +- return __get_nprocs (); ++ enum { buffer_size = 1024 }; ++ char buffer[buffer_size]; ++ char *buffer_end = buffer + buffer_size; ++ char *cp = buffer_end; ++ char *re = buffer_end; ++ ++ const int flags = O_RDONLY | O_CLOEXEC; ++ /* This file contains comma-separated ranges. */ ++ int fd = __open_nocancel ("/sys/devices/system/cpu/online", flags); ++ char *l; ++ int result = 0; ++ if (fd != -1) ++ { ++ l = next_line (fd, buffer, &cp, &re, buffer_end); ++ if (l != NULL) ++ do ++ { ++ char *endp; ++ unsigned long int n = strtoul (l, &endp, 10); ++ if (l == endp) ++ { ++ result = 0; ++ break; ++ } ++ ++ unsigned long int m = n; ++ if (*endp == '-') ++ { ++ l = endp + 1; ++ m = strtoul (l, &endp, 10); ++ if (l == endp) ++ { ++ result = 0; ++ break; ++ } ++ } ++ ++ result += m - n + 1; ++ ++ l = endp; ++ if (l < re && *l == ',') ++ ++l; ++ } ++ while (l < re && *l != '\n'); ++ ++ __close_nocancel_nostatus (fd); ++ ++ if (result > 0) ++ return result; ++ } ++ ++ cp = buffer_end; ++ re = buffer_end; ++ ++ /* Default to an SMP system in case we cannot obtain an accurate ++ number. */ ++ result = 2; ++ ++ fd = __open_nocancel ("/proc/stat", flags); ++ if (fd != -1) ++ { ++ result = 0; ++ ++ while ((l = next_line (fd, buffer, &cp, &re, buffer_end)) != NULL) ++ /* The current format of /proc/stat has all the cpu* entries ++ at the front. We assume here that stays this way. */ ++ if (strncmp (l, "cpu", 3) != 0) ++ break; ++ else if (isdigit (l[3])) ++ ++result; ++ ++ __close_nocancel_nostatus (fd); ++ } ++ ++ return result; + } ++libc_hidden_def (__get_nprocs) ++weak_alias (__get_nprocs, get_nprocs) + + + /* On some architectures it is possible to distinguish between configured +-- +1.8.3.1 + diff --git a/linux-Simplify-get_nprocs.patch b/linux-Simplify-get_nprocs.patch new file mode 100644 index 0000000..55c49b2 --- /dev/null +++ b/linux-Simplify-get_nprocs.patch @@ -0,0 +1,216 @@ +From cda99af14e82b4bb6abaecd717ebe3b57c0aa534 Mon Sep 17 00:00:00 2001 +From: Adhemerval Zanella +Date: Mon, 6 Sep 2021 12:28:24 -0300 +Subject: [PATCH] linux: Simplify get_nprocs + +This patch simplifies the memory allocation code and uses the sched +routines instead of reimplement it. This still uses a stack +allocation buffer, so it can be used on malloc initialization code. + +Linux currently supports at maximum of 4096 cpus for most architectures: + +$ find -iname Kconfig | xargs git grep -A10 -w NR_CPUS | grep -w range +arch/alpha/Kconfig- range 2 32 +arch/arc/Kconfig- range 2 4096 +arch/arm/Kconfig- range 2 16 if DEBUG_KMAP_LOCAL +arch/arm/Kconfig- range 2 32 if !DEBUG_KMAP_LOCAL +arch/arm64/Kconfig- range 2 4096 +arch/csky/Kconfig- range 2 32 +arch/hexagon/Kconfig- range 2 6 if SMP +arch/ia64/Kconfig- range 2 4096 +arch/mips/Kconfig- range 2 256 +arch/openrisc/Kconfig- range 2 32 +arch/parisc/Kconfig- range 2 32 +arch/riscv/Kconfig- range 2 32 +arch/s390/Kconfig- range 2 512 +arch/sh/Kconfig- range 2 32 +arch/sparc/Kconfig- range 2 32 if SPARC32 +arch/sparc/Kconfig- range 2 4096 if SPARC64 +arch/um/Kconfig- range 1 1 +arch/x86/Kconfig-# [NR_CPUS_RANGE_BEGIN ... NR_CPUS_RANGE_END] range. +arch/x86/Kconfig- range NR_CPUS_RANGE_BEGIN NR_CPUS_RANGE_END +arch/xtensa/Kconfig- range 2 32 + +With x86 supporting 8192: + +arch/x86/Kconfig + 976 config NR_CPUS_RANGE_END + 977 int + 978 depends on X86_64 + 979 default 8192 if SMP && CPUMASK_OFFSTACK + 980 default 512 if SMP && !CPUMASK_OFFSTACK + 981 default 1 if !SMP + +So using a maximum of 32k cpu should cover all cases (and I would +expect once we start to have many more CPUs that Linux would provide +a more straightforward way to query for such information). + +A test is added to check if sched_getaffinity can successfully return +with large buffers. + +Checked on x86_64-linux-gnu and i686-linux-gnu. + +Reviewed-by: Florian Weimer +(cherry picked from commit 33099d72e41cf8a129b362e9709eb2be9372d844) +--- + posix/Makefile | 3 +- + posix/tst-sched_getaffinity.c | 48 +++++++++++++++++++++++++ + sysdeps/unix/sysv/linux/getsysstats.c | 68 ++++++++++------------------------- + 3 files changed, 68 insertions(+), 51 deletions(-) + create mode 100644 posix/tst-sched_getaffinity.c + +diff --git a/posix/Makefile b/posix/Makefile +index 059efb3..09460a2 100644 +--- a/posix/Makefile ++++ b/posix/Makefile +@@ -107,7 +107,8 @@ tests := test-errno tstgetopt testfnm runtests runptests \ + tst-sysconf-empty-chroot tst-glob_symlinks tst-fexecve \ + tst-glob-tilde test-ssize-max tst-spawn4 bug-regex37 \ + bug-regex38 tst-regcomp-truncated tst-spawn-chdir \ +- tst-wordexp-nocmd tst-execveat tst-spawn5 ++ tst-wordexp-nocmd tst-execveat tst-spawn5 \ ++ tst-sched_getaffinity + + # Test for the glob symbol version that was replaced in glibc 2.27. + ifeq ($(have-GLIBC_2.26)$(build-shared),yesyes) +diff --git a/posix/tst-sched_getaffinity.c b/posix/tst-sched_getaffinity.c +new file mode 100644 +index 0000000..db9d517 +--- /dev/null ++++ b/posix/tst-sched_getaffinity.c +@@ -0,0 +1,48 @@ ++/* Tests for sched_getaffinity with large buffers. ++ Copyright (C) 2021 Free Software Foundation, Inc. ++ This file is part of the GNU C Library. ++ ++ The GNU C Library is free software; you can redistribute it and/or ++ modify it under the terms of the GNU Lesser General Public ++ License as published by the Free Software Foundation; either ++ version 2.1 of the License, or (at your option) any later version. ++ ++ The GNU C Library is distributed in the hope that it will be useful, ++ but WITHOUT ANY WARRANTY; without even the implied warranty of ++ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU ++ Lesser General Public License for more details. ++ ++ You should have received a copy of the GNU Lesser General Public ++ License along with the GNU C Library; if not, see ++ . */ ++ ++#include ++#include ++#include ++ ++/* NB: this test may fail on system with more than 32k cpus. */ ++ ++static int ++do_test (void) ++{ ++ /* The values are larger than the default cpu_set_t. */ ++ const int bufsize[] = { 1<<11, 1<<12, 1<<13, 1<<14, 1<<15, 1<<16, 1<<17 }; ++ int cpucount[array_length (bufsize)]; ++ ++ for (int i = 0; i < array_length (bufsize); i++) ++ { ++ cpu_set_t *cpuset = CPU_ALLOC (bufsize[i]); ++ TEST_VERIFY (cpuset != NULL); ++ size_t size = CPU_ALLOC_SIZE (bufsize[i]); ++ TEST_COMPARE (sched_getaffinity (0, size, cpuset), 0); ++ cpucount[i] = CPU_COUNT_S (size, cpuset); ++ CPU_FREE (cpuset); ++ } ++ ++ for (int i = 0; i < array_length (cpucount) - 1; i++) ++ TEST_COMPARE (cpucount[i], cpucount[i + 1]); ++ ++ return 0; ++} ++ ++#include +diff --git a/sysdeps/unix/sysv/linux/getsysstats.c b/sysdeps/unix/sysv/linux/getsysstats.c +index 120ce1b..61d20e7 100644 +--- a/sysdeps/unix/sysv/linux/getsysstats.c ++++ b/sysdeps/unix/sysv/linux/getsysstats.c +@@ -29,61 +29,29 @@ + #include + #include + +-/* Compute the population count of the entire array. */ +-static int +-__get_nprocs_count (const unsigned long int *array, size_t length) +-{ +- int count = 0; +- for (size_t i = 0; i < length; ++i) +- if (__builtin_add_overflow (count, __builtin_popcountl (array[i]), +- &count)) +- return INT_MAX; +- return count; +-} +- +-/* __get_nprocs with a large buffer. */ +-static int +-__get_nprocs_large (void) +-{ +- /* This code cannot use scratch_buffer because it is used during +- malloc initialization. */ +- size_t pagesize = GLRO (dl_pagesize); +- unsigned long int *page = __mmap (0, pagesize, PROT_READ | PROT_WRITE, +- MAP_ANONYMOUS | MAP_PRIVATE, -1, 0); +- if (page == MAP_FAILED) +- return 2; +- int r = INTERNAL_SYSCALL_CALL (sched_getaffinity, 0, pagesize, page); +- int count; +- if (r > 0) +- count = __get_nprocs_count (page, pagesize / sizeof (unsigned long int)); +- else if (r == -EINVAL) +- /* One page is still not enough to store the bits. A more-or-less +- arbitrary value. This assumes t hat such large systems never +- happen in practice. */ +- count = GLRO (dl_pagesize) * CHAR_BIT; +- else +- count = 2; +- __munmap (page, GLRO (dl_pagesize)); +- return count; +-} +- + int + __get_nprocs (void) + { +- /* Fast path for most systems. The kernel expects a buffer size +- that is a multiple of 8. */ +- unsigned long int small_buffer[1024 / CHAR_BIT / sizeof (unsigned long int)]; +- int r = INTERNAL_SYSCALL_CALL (sched_getaffinity, 0, +- sizeof (small_buffer), small_buffer); ++ enum ++ { ++ max_num_cpus = 32768, ++ cpu_bits_size = CPU_ALLOC_SIZE (32768) ++ }; ++ ++ /* This cannot use malloc because it is used on malloc initialization. */ ++ __cpu_mask cpu_bits[cpu_bits_size / sizeof (__cpu_mask)]; ++ int r = INTERNAL_SYSCALL_CALL (sched_getaffinity, 0, cpu_bits_size, ++ cpu_bits); + if (r > 0) +- return __get_nprocs_count (small_buffer, r / sizeof (unsigned long int)); ++ return CPU_COUNT_S (cpu_bits_size, (cpu_set_t*) cpu_bits); + else if (r == -EINVAL) +- /* The kernel requests a larger buffer to store the data. */ +- return __get_nprocs_large (); +- else +- /* Some other error. 2 is conservative (not a uniprocessor +- system, so atomics are needed). */ +- return 2; ++ /* The input buffer is still not enough to store the number of cpus. This ++ is an arbitrary values assuming such systems should be rare and there ++ is no offline cpus. */ ++ return max_num_cpus; ++ /* Some other error. 2 is conservative (not a uniprocessor system, so ++ atomics are needed). */ ++ return 2; + } + libc_hidden_def (__get_nprocs) + weak_alias (__get_nprocs, get_nprocs) +-- +1.8.3.1 + diff --git a/misc-Add-__get_nprocs_sched.patch b/misc-Add-__get_nprocs_sched.patch new file mode 100644 index 0000000..68e1208 --- /dev/null +++ b/misc-Add-__get_nprocs_sched.patch @@ -0,0 +1,110 @@ +From e870aac8974cda746157a5a3c9f452ccd70da29b Mon Sep 17 00:00:00 2001 +From: Adhemerval Zanella +Date: Mon, 6 Sep 2021 12:22:54 -0300 +Subject: [PATCH] misc: Add __get_nprocs_sched + +This is an internal function meant to return the number of avaliable +processor where the process can scheduled, different than the +__get_nprocs which returns a the system available online CPU. + +The Linux implementation currently only calls __get_nprocs(), which +in tuns calls sched_getaffinity. + +Reviewed-by: Florian Weimer +(cherry picked from commit 11a02b035b464ab6813676adfd19c4a59c36d907) +--- + include/sys/sysinfo.h | 7 ++++++- + malloc/arena.c | 2 +- + misc/getsysstats.c | 6 ++++++ + sysdeps/mach/getsysstats.c | 6 ++++++ + sysdeps/unix/sysv/linux/getsysstats.c | 6 ++++++ + 5 files changed, 25 insertions(+), 2 deletions(-) + +diff --git a/include/sys/sysinfo.h b/include/sys/sysinfo.h +index 7388356..c490561 100644 +--- a/include/sys/sysinfo.h ++++ b/include/sys/sysinfo.h +@@ -9,10 +9,15 @@ + extern int __get_nprocs_conf (void); + libc_hidden_proto (__get_nprocs_conf) + +-/* Return number of available processors. */ ++/* Return number of available processors (not all of them will be ++ available to the caller process). */ + extern int __get_nprocs (void); + libc_hidden_proto (__get_nprocs) + ++/* Return the number of available processors which the process can ++ be scheduled. */ ++extern int __get_nprocs_sched (void) attribute_hidden; ++ + /* Return number of physical pages of memory in the system. */ + extern long int __get_phys_pages (void); + libc_hidden_proto (__get_phys_pages) +diff --git a/malloc/arena.c b/malloc/arena.c +index 6674846..f1f0af8 100644 +--- a/malloc/arena.c ++++ b/malloc/arena.c +@@ -879,7 +879,7 @@ arena_get2 (size_t size, mstate avoid_arena) + narenas_limit = mp_.arena_max; + else if (narenas > mp_.arena_test) + { +- int n = __get_nprocs (); ++ int n = __get_nprocs_sched (); + + if (n >= 1) + narenas_limit = NARENAS_FROM_NCORES (n); +diff --git a/misc/getsysstats.c b/misc/getsysstats.c +index 0eedfac..57d9360 100644 +--- a/misc/getsysstats.c ++++ b/misc/getsysstats.c +@@ -45,6 +45,12 @@ weak_alias (__get_nprocs, get_nprocs) + link_warning (get_nprocs, "warning: get_nprocs will always return 1") + + ++int ++__get_nprocs_sched (void) ++{ ++ return 1; ++} ++ + long int + __get_phys_pages (void) + { +diff --git a/sysdeps/mach/getsysstats.c b/sysdeps/mach/getsysstats.c +index 1267f39..cc8023f 100644 +--- a/sysdeps/mach/getsysstats.c ++++ b/sysdeps/mach/getsysstats.c +@@ -62,6 +62,12 @@ __get_nprocs (void) + libc_hidden_def (__get_nprocs) + weak_alias (__get_nprocs, get_nprocs) + ++int ++__get_nprocs_sched (void) ++{ ++ return __get_nprocs (); ++} ++ + /* Return the number of physical pages on the system. */ + long int + __get_phys_pages (void) +diff --git a/sysdeps/unix/sysv/linux/getsysstats.c b/sysdeps/unix/sysv/linux/getsysstats.c +index 1391e36..120ce1b 100644 +--- a/sysdeps/unix/sysv/linux/getsysstats.c ++++ b/sysdeps/unix/sysv/linux/getsysstats.c +@@ -88,6 +88,12 @@ __get_nprocs (void) + libc_hidden_def (__get_nprocs) + weak_alias (__get_nprocs, get_nprocs) + ++int ++__get_nprocs_sched (void) ++{ ++ return __get_nprocs (); ++} ++ + + /* On some architectures it is possible to distinguish between configured + and active cpus. */ +-- +1.8.3.1 + -- Gitee