diff options
Diffstat (limited to 'tools/testing/selftests/powerpc/mm')
| -rw-r--r-- | tools/testing/selftests/powerpc/mm/.gitignore | 5 | ||||
| -rw-r--r-- | tools/testing/selftests/powerpc/mm/Makefile | 19 | ||||
| -rw-r--r-- | tools/testing/selftests/powerpc/mm/hugetlb_vs_thp_test.c | 77 | ||||
| -rw-r--r-- | tools/testing/selftests/powerpc/mm/prot_sao.c | 42 | ||||
| -rw-r--r-- | tools/testing/selftests/powerpc/mm/segv_errors.c | 78 | ||||
| -rw-r--r-- | tools/testing/selftests/powerpc/mm/subpage_prot.c | 236 | ||||
| -rw-r--r-- | tools/testing/selftests/powerpc/mm/tlbie_test.c | 734 |
7 files changed, 1191 insertions, 0 deletions
diff --git a/tools/testing/selftests/powerpc/mm/.gitignore b/tools/testing/selftests/powerpc/mm/.gitignore new file mode 100644 index 000000000..7d7c42ed6 --- /dev/null +++ b/tools/testing/selftests/powerpc/mm/.gitignore @@ -0,0 +1,5 @@ +hugetlb_vs_thp_test +subpage_prot +tempfile +prot_sao +segv_errors
\ No newline at end of file diff --git a/tools/testing/selftests/powerpc/mm/Makefile b/tools/testing/selftests/powerpc/mm/Makefile new file mode 100644 index 000000000..869628234 --- /dev/null +++ b/tools/testing/selftests/powerpc/mm/Makefile @@ -0,0 +1,19 @@ +# SPDX-License-Identifier: GPL-2.0 +noarg: + $(MAKE) -C ../ + +TEST_GEN_PROGS := hugetlb_vs_thp_test subpage_prot prot_sao segv_errors +TEST_GEN_PROGS_EXTENDED := tlbie_test +TEST_GEN_FILES := tempfile + +top_srcdir = ../../../../.. +include ../../lib.mk + +$(TEST_GEN_PROGS): ../harness.c + +$(OUTPUT)/prot_sao: ../utils.c + +$(OUTPUT)/tempfile: + dd if=/dev/zero of=$@ bs=64k count=1 + +$(OUTPUT)/tlbie_test: LDLIBS += -lpthread diff --git a/tools/testing/selftests/powerpc/mm/hugetlb_vs_thp_test.c b/tools/testing/selftests/powerpc/mm/hugetlb_vs_thp_test.c new file mode 100644 index 000000000..9932359ce --- /dev/null +++ b/tools/testing/selftests/powerpc/mm/hugetlb_vs_thp_test.c @@ -0,0 +1,77 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <stdio.h> +#include <sys/mman.h> +#include <unistd.h> + +#include "utils.h" + +/* This must match the huge page & THP size */ +#define SIZE (16 * 1024 * 1024) + +static int test_body(void) +{ + void *addr; + char *p; + + addr = (void *)0xa0000000; + + p = mmap(addr, SIZE, PROT_READ | PROT_WRITE, + MAP_HUGETLB | MAP_ANONYMOUS | MAP_PRIVATE, -1, 0); + if (p != MAP_FAILED) { + /* + * Typically the mmap will fail because no huge pages are + * allocated on the system. But if there are huge pages + * allocated the mmap will succeed. That's fine too, we just + * munmap here before continuing. munmap() length of + * MAP_HUGETLB memory must be hugepage aligned. + */ + if (munmap(addr, SIZE)) { + perror("munmap"); + return 1; + } + } + + p = mmap(addr, SIZE, PROT_READ | PROT_WRITE, + MAP_ANONYMOUS | MAP_PRIVATE, -1, 0); + if (p == MAP_FAILED) { + printf("Mapping failed @ %p\n", addr); + perror("mmap"); + return 1; + } + + /* + * Either a user or kernel access is sufficient to trigger the bug. + * A kernel access is easier to spot & debug, as it will trigger the + * softlockup or RCU stall detectors, and when the system is kicked + * into xmon we get a backtrace in the kernel. + * + * A good option is: + * getcwd(p, SIZE); + * + * For the purposes of this testcase it's preferable to spin in + * userspace, so the harness can kill us if we get stuck. That way we + * see a test failure rather than a dead system. + */ + *p = 0xf; + + munmap(addr, SIZE); + + return 0; +} + +static int test_main(void) +{ + int i; + + /* 10,000 because it's a "bunch", and completes reasonably quickly */ + for (i = 0; i < 10000; i++) + if (test_body()) + return 1; + + return 0; +} + +int main(void) +{ + return test_harness(test_main, "hugetlb_vs_thp"); +} diff --git a/tools/testing/selftests/powerpc/mm/prot_sao.c b/tools/testing/selftests/powerpc/mm/prot_sao.c new file mode 100644 index 000000000..611530d43 --- /dev/null +++ b/tools/testing/selftests/powerpc/mm/prot_sao.c @@ -0,0 +1,42 @@ +/* + * Copyright 2016, Michael Ellerman, IBM Corp. + * Licensed under GPLv2. + */ + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sys/mman.h> + +#include <asm/cputable.h> + +#include "utils.h" + +#define SIZE (64 * 1024) + +int test_prot_sao(void) +{ + char *p; + + /* 2.06 or later should support SAO */ + SKIP_IF(!have_hwcap(PPC_FEATURE_ARCH_2_06)); + + /* + * Ensure we can ask for PROT_SAO. + * We can't really verify that it does the right thing, but at least we + * confirm the kernel will accept it. + */ + p = mmap(NULL, SIZE, PROT_READ | PROT_WRITE | PROT_SAO, + MAP_ANONYMOUS | MAP_PRIVATE, -1, 0); + FAIL_IF(p == MAP_FAILED); + + /* Write to the mapping, to at least cause a fault */ + memset(p, 0xaa, SIZE); + + return 0; +} + +int main(void) +{ + return test_harness(test_prot_sao, "prot-sao"); +} diff --git a/tools/testing/selftests/powerpc/mm/segv_errors.c b/tools/testing/selftests/powerpc/mm/segv_errors.c new file mode 100644 index 000000000..06ae76ee3 --- /dev/null +++ b/tools/testing/selftests/powerpc/mm/segv_errors.c @@ -0,0 +1,78 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* + * Copyright 2017 John Sperbeck + * + * Test that an access to a mapped but inaccessible area causes a SEGV and + * reports si_code == SEGV_ACCERR. + */ + +#include <stdbool.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <signal.h> +#include <sys/mman.h> +#include <assert.h> +#include <ucontext.h> + +#include "utils.h" + +static bool faulted; +static int si_code; + +static void segv_handler(int n, siginfo_t *info, void *ctxt_v) +{ + ucontext_t *ctxt = (ucontext_t *)ctxt_v; + struct pt_regs *regs = ctxt->uc_mcontext.regs; + + faulted = true; + si_code = info->si_code; + regs->nip += 4; +} + +int test_segv_errors(void) +{ + struct sigaction act = { + .sa_sigaction = segv_handler, + .sa_flags = SA_SIGINFO, + }; + char c, *p = NULL; + + p = mmap(NULL, getpagesize(), 0, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); + FAIL_IF(p == MAP_FAILED); + + FAIL_IF(sigaction(SIGSEGV, &act, NULL) != 0); + + faulted = false; + si_code = 0; + + /* + * We just need a compiler barrier, but mb() works and has the nice + * property of being easy to spot in the disassembly. + */ + mb(); + c = *p; + mb(); + + FAIL_IF(!faulted); + FAIL_IF(si_code != SEGV_ACCERR); + + faulted = false; + si_code = 0; + + mb(); + *p = c; + mb(); + + FAIL_IF(!faulted); + FAIL_IF(si_code != SEGV_ACCERR); + + return 0; +} + +int main(void) +{ + return test_harness(test_segv_errors, "segv_errors"); +} diff --git a/tools/testing/selftests/powerpc/mm/subpage_prot.c b/tools/testing/selftests/powerpc/mm/subpage_prot.c new file mode 100644 index 000000000..3ae77ba93 --- /dev/null +++ b/tools/testing/selftests/powerpc/mm/subpage_prot.c @@ -0,0 +1,236 @@ +/* + * Copyright IBM Corp. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of version 2.1 of the GNU Lesser General Public License + * as published by the Free Software Foundation. + * + * This program is distributed in the hope that it would be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. + * + */ + +#include <assert.h> +#include <errno.h> +#include <fcntl.h> +#include <signal.h> +#include <stdarg.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sys/mman.h> +#include <sys/ptrace.h> +#include <sys/syscall.h> +#include <ucontext.h> +#include <unistd.h> + +#include "utils.h" + +char *file_name; + +int in_test; +volatile int faulted; +volatile void *dar; +int errors; + +static void segv(int signum, siginfo_t *info, void *ctxt_v) +{ + ucontext_t *ctxt = (ucontext_t *)ctxt_v; + struct pt_regs *regs = ctxt->uc_mcontext.regs; + + if (!in_test) { + fprintf(stderr, "Segfault outside of test !\n"); + exit(1); + } + + faulted = 1; + dar = (void *)regs->dar; + regs->nip += 4; +} + +static inline void do_read(const volatile void *addr) +{ + int ret; + + asm volatile("lwz %0,0(%1); twi 0,%0,0; isync;\n" + : "=r" (ret) : "r" (addr) : "memory"); +} + +static inline void do_write(const volatile void *addr) +{ + int val = 0x1234567; + + asm volatile("stw %0,0(%1); sync; \n" + : : "r" (val), "r" (addr) : "memory"); +} + +static inline void check_faulted(void *addr, long page, long subpage, int write) +{ + int want_fault = (subpage == ((page + 3) % 16)); + + if (write) + want_fault |= (subpage == ((page + 1) % 16)); + + if (faulted != want_fault) { + printf("Failed at %p (p=%ld,sp=%ld,w=%d), want=%s, got=%s !\n", + addr, page, subpage, write, + want_fault ? "fault" : "pass", + faulted ? "fault" : "pass"); + ++errors; + } + + if (faulted) { + if (dar != addr) { + printf("Fault expected at %p and happened at %p !\n", + addr, dar); + } + faulted = 0; + asm volatile("sync" : : : "memory"); + } +} + +static int run_test(void *addr, unsigned long size) +{ + unsigned int *map; + long i, j, pages, err; + + pages = size / 0x10000; + map = malloc(pages * 4); + assert(map); + + /* + * for each page, mark subpage i % 16 read only and subpage + * (i + 3) % 16 inaccessible + */ + for (i = 0; i < pages; i++) { + map[i] = (0x40000000 >> (((i + 1) * 2) % 32)) | + (0xc0000000 >> (((i + 3) * 2) % 32)); + } + + err = syscall(__NR_subpage_prot, addr, size, map); + if (err) { + perror("subpage_perm"); + return 1; + } + free(map); + + in_test = 1; + errors = 0; + for (i = 0; i < pages; i++) { + for (j = 0; j < 16; j++, addr += 0x1000) { + do_read(addr); + check_faulted(addr, i, j, 0); + do_write(addr); + check_faulted(addr, i, j, 1); + } + } + + in_test = 0; + if (errors) { + printf("%d errors detected\n", errors); + return 1; + } + + return 0; +} + +static int syscall_available(void) +{ + int rc; + + errno = 0; + rc = syscall(__NR_subpage_prot, 0, 0, 0); + + return rc == 0 || (errno != ENOENT && errno != ENOSYS); +} + +int test_anon(void) +{ + unsigned long align; + struct sigaction act = { + .sa_sigaction = segv, + .sa_flags = SA_SIGINFO + }; + void *mallocblock; + unsigned long mallocsize; + + SKIP_IF(!syscall_available()); + + if (getpagesize() != 0x10000) { + fprintf(stderr, "Kernel page size must be 64K!\n"); + return 1; + } + + sigaction(SIGSEGV, &act, NULL); + + mallocsize = 4 * 16 * 1024 * 1024; + + FAIL_IF(posix_memalign(&mallocblock, 64 * 1024, mallocsize)); + + align = (unsigned long)mallocblock; + if (align & 0xffff) + align = (align | 0xffff) + 1; + + mallocblock = (void *)align; + + printf("allocated malloc block of 0x%lx bytes at %p\n", + mallocsize, mallocblock); + + printf("testing malloc block...\n"); + + return run_test(mallocblock, mallocsize); +} + +int test_file(void) +{ + struct sigaction act = { + .sa_sigaction = segv, + .sa_flags = SA_SIGINFO + }; + void *fileblock; + off_t filesize; + int fd; + + SKIP_IF(!syscall_available()); + + fd = open(file_name, O_RDWR); + if (fd == -1) { + perror("failed to open file"); + return 1; + } + sigaction(SIGSEGV, &act, NULL); + + filesize = lseek(fd, 0, SEEK_END); + if (filesize & 0xffff) + filesize &= ~0xfffful; + + fileblock = mmap(NULL, filesize, PROT_READ | PROT_WRITE, + MAP_SHARED, fd, 0); + if (fileblock == MAP_FAILED) { + perror("failed to map file"); + return 1; + } + printf("allocated %s for 0x%lx bytes at %p\n", + file_name, filesize, fileblock); + + printf("testing file map...\n"); + + return run_test(fileblock, filesize); +} + +int main(int argc, char *argv[]) +{ + int rc; + + rc = test_harness(test_anon, "subpage_prot_anon"); + if (rc) + return rc; + + if (argc > 1) + file_name = argv[1]; + else + file_name = "tempfile"; + + return test_harness(test_file, "subpage_prot_file"); +} diff --git a/tools/testing/selftests/powerpc/mm/tlbie_test.c b/tools/testing/selftests/powerpc/mm/tlbie_test.c new file mode 100644 index 000000000..f85a0938a --- /dev/null +++ b/tools/testing/selftests/powerpc/mm/tlbie_test.c @@ -0,0 +1,734 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* + * Copyright 2019, Nick Piggin, Gautham R. Shenoy, Aneesh Kumar K.V, IBM Corp. + */ + +/* + * + * Test tlbie/mtpidr race. We have 4 threads doing flush/load/compare/store + * sequence in a loop. The same threads also rung a context switch task + * that does sched_yield() in loop. + * + * The snapshot thread mark the mmap area PROT_READ in between, make a copy + * and copy it back to the original area. This helps us to detect if any + * store continued to happen after we marked the memory PROT_READ. + */ + +#define _GNU_SOURCE +#include <stdio.h> +#include <sys/mman.h> +#include <sys/types.h> +#include <sys/wait.h> +#include <sys/ipc.h> +#include <sys/shm.h> +#include <sys/stat.h> +#include <sys/time.h> +#include <linux/futex.h> +#include <unistd.h> +#include <asm/unistd.h> +#include <string.h> +#include <stdlib.h> +#include <fcntl.h> +#include <sched.h> +#include <time.h> +#include <stdarg.h> +#include <sched.h> +#include <pthread.h> +#include <signal.h> +#include <sys/prctl.h> + +static inline void dcbf(volatile unsigned int *addr) +{ + __asm__ __volatile__ ("dcbf %y0; sync" : : "Z"(*(unsigned char *)addr) : "memory"); +} + +static void err_msg(char *msg) +{ + + time_t now; + time(&now); + printf("=================================\n"); + printf(" Error: %s\n", msg); + printf(" %s", ctime(&now)); + printf("=================================\n"); + exit(1); +} + +static char *map1; +static char *map2; +static pid_t rim_process_pid; + +/* + * A "rim-sequence" is defined to be the sequence of the following + * operations performed on a memory word: + * 1) FLUSH the contents of that word. + * 2) LOAD the contents of that word. + * 3) COMPARE the contents of that word with the content that was + * previously stored at that word + * 4) STORE new content into that word. + * + * The threads in this test that perform the rim-sequence are termed + * as rim_threads. + */ + +/* + * A "corruption" is defined to be the failed COMPARE operation in a + * rim-sequence. + * + * A rim_thread that detects a corruption informs about it to all the + * other rim_threads, and the mem_snapshot thread. + */ +static volatile unsigned int corruption_found; + +/* + * This defines the maximum number of rim_threads in this test. + * + * The THREAD_ID_BITS denote the number of bits required + * to represent the thread_ids [0..MAX_THREADS - 1]. + * We are being a bit paranoid here and set it to 8 bits, + * though 6 bits suffice. + * + */ +#define MAX_THREADS 64 +#define THREAD_ID_BITS 8 +#define THREAD_ID_MASK ((1 << THREAD_ID_BITS) - 1) +static unsigned int rim_thread_ids[MAX_THREADS]; +static pthread_t rim_threads[MAX_THREADS]; + + +/* + * Each rim_thread works on an exclusive "chunk" of size + * RIM_CHUNK_SIZE. + * + * The ith rim_thread works on the ith chunk. + * + * The ith chunk begins at + * map1 + (i * RIM_CHUNK_SIZE) + */ +#define RIM_CHUNK_SIZE 1024 +#define BITS_PER_BYTE 8 +#define WORD_SIZE (sizeof(unsigned int)) +#define WORD_BITS (WORD_SIZE * BITS_PER_BYTE) +#define WORDS_PER_CHUNK (RIM_CHUNK_SIZE/WORD_SIZE) + +static inline char *compute_chunk_start_addr(unsigned int thread_id) +{ + char *chunk_start; + + chunk_start = (char *)((unsigned long)map1 + + (thread_id * RIM_CHUNK_SIZE)); + + return chunk_start; +} + +/* + * The "word-offset" of a word-aligned address inside a chunk, is + * defined to be the number of words that precede the address in that + * chunk. + * + * WORD_OFFSET_BITS denote the number of bits required to represent + * the word-offsets of all the word-aligned addresses of a chunk. + */ +#define WORD_OFFSET_BITS (__builtin_ctz(WORDS_PER_CHUNK)) +#define WORD_OFFSET_MASK ((1 << WORD_OFFSET_BITS) - 1) + +static inline unsigned int compute_word_offset(char *start, unsigned int *addr) +{ + unsigned int delta_bytes, ret; + delta_bytes = (unsigned long)addr - (unsigned long)start; + + ret = delta_bytes/WORD_SIZE; + + return ret; +} + +/* + * A "sweep" is defined to be the sequential execution of the + * rim-sequence by a rim_thread on its chunk one word at a time, + * starting from the first word of its chunk and ending with the last + * word of its chunk. + * + * Each sweep of a rim_thread is uniquely identified by a sweep_id. + * SWEEP_ID_BITS denote the number of bits required to represent + * the sweep_ids of rim_threads. + * + * As to why SWEEP_ID_BITS are computed as a function of THREAD_ID_BITS, + * WORD_OFFSET_BITS, and WORD_BITS, see the "store-pattern" below. + */ +#define SWEEP_ID_BITS (WORD_BITS - (THREAD_ID_BITS + WORD_OFFSET_BITS)) +#define SWEEP_ID_MASK ((1 << SWEEP_ID_BITS) - 1) + +/* + * A "store-pattern" is the word-pattern that is stored into a word + * location in the 4)STORE step of the rim-sequence. + * + * In the store-pattern, we shall encode: + * + * - The thread-id of the rim_thread performing the store + * (The most significant THREAD_ID_BITS) + * + * - The word-offset of the address into which the store is being + * performed (The next WORD_OFFSET_BITS) + * + * - The sweep_id of the current sweep in which the store is + * being performed. (The lower SWEEP_ID_BITS) + * + * Store Pattern: 32 bits + * |------------------|--------------------|---------------------------------| + * | Thread id | Word offset | sweep_id | + * |------------------|--------------------|---------------------------------| + * THREAD_ID_BITS WORD_OFFSET_BITS SWEEP_ID_BITS + * + * In the store pattern, the (Thread-id + Word-offset) uniquely identify the + * address to which the store is being performed i.e, + * address == map1 + + * (Thread-id * RIM_CHUNK_SIZE) + (Word-offset * WORD_SIZE) + * + * And the sweep_id in the store pattern identifies the time when the + * store was performed by the rim_thread. + * + * We shall use this property in the 3)COMPARE step of the + * rim-sequence. + */ +#define SWEEP_ID_SHIFT 0 +#define WORD_OFFSET_SHIFT (SWEEP_ID_BITS) +#define THREAD_ID_SHIFT (WORD_OFFSET_BITS + SWEEP_ID_BITS) + +/* + * Compute the store pattern for a given thread with id @tid, at + * location @addr in the sweep identified by @sweep_id + */ +static inline unsigned int compute_store_pattern(unsigned int tid, + unsigned int *addr, + unsigned int sweep_id) +{ + unsigned int ret = 0; + char *start = compute_chunk_start_addr(tid); + unsigned int word_offset = compute_word_offset(start, addr); + + ret += (tid & THREAD_ID_MASK) << THREAD_ID_SHIFT; + ret += (word_offset & WORD_OFFSET_MASK) << WORD_OFFSET_SHIFT; + ret += (sweep_id & SWEEP_ID_MASK) << SWEEP_ID_SHIFT; + return ret; +} + +/* Extract the thread-id from the given store-pattern */ +static inline unsigned int extract_tid(unsigned int pattern) +{ + unsigned int ret; + + ret = (pattern >> THREAD_ID_SHIFT) & THREAD_ID_MASK; + return ret; +} + +/* Extract the word-offset from the given store-pattern */ +static inline unsigned int extract_word_offset(unsigned int pattern) +{ + unsigned int ret; + + ret = (pattern >> WORD_OFFSET_SHIFT) & WORD_OFFSET_MASK; + + return ret; +} + +/* Extract the sweep-id from the given store-pattern */ +static inline unsigned int extract_sweep_id(unsigned int pattern) + +{ + unsigned int ret; + + ret = (pattern >> SWEEP_ID_SHIFT) & SWEEP_ID_MASK; + + return ret; +} + +/************************************************************ + * * + * Logging the output of the verification * + * * + ************************************************************/ +#define LOGDIR_NAME_SIZE 100 +static char logdir[LOGDIR_NAME_SIZE]; + +static FILE *fp[MAX_THREADS]; +static const char logfilename[] ="Thread-%02d-Chunk"; + +static inline void start_verification_log(unsigned int tid, + unsigned int *addr, + unsigned int cur_sweep_id, + unsigned int prev_sweep_id) +{ + FILE *f; + char logfile[30]; + char path[LOGDIR_NAME_SIZE + 30]; + char separator[2] = "/"; + char *chunk_start = compute_chunk_start_addr(tid); + unsigned int size = RIM_CHUNK_SIZE; + + sprintf(logfile, logfilename, tid); + strcpy(path, logdir); + strcat(path, separator); + strcat(path, logfile); + f = fopen(path, "w"); + + if (!f) { + err_msg("Unable to create logfile\n"); + } + + fp[tid] = f; + + fprintf(f, "----------------------------------------------------------\n"); + fprintf(f, "PID = %d\n", rim_process_pid); + fprintf(f, "Thread id = %02d\n", tid); + fprintf(f, "Chunk Start Addr = 0x%016lx\n", (unsigned long)chunk_start); + fprintf(f, "Chunk Size = %d\n", size); + fprintf(f, "Next Store Addr = 0x%016lx\n", (unsigned long)addr); + fprintf(f, "Current sweep-id = 0x%08x\n", cur_sweep_id); + fprintf(f, "Previous sweep-id = 0x%08x\n", prev_sweep_id); + fprintf(f, "----------------------------------------------------------\n"); +} + +static inline void log_anamoly(unsigned int tid, unsigned int *addr, + unsigned int expected, unsigned int observed) +{ + FILE *f = fp[tid]; + + fprintf(f, "Thread %02d: Addr 0x%lx: Expected 0x%x, Observed 0x%x\n", + tid, (unsigned long)addr, expected, observed); + fprintf(f, "Thread %02d: Expected Thread id = %02d\n", tid, extract_tid(expected)); + fprintf(f, "Thread %02d: Observed Thread id = %02d\n", tid, extract_tid(observed)); + fprintf(f, "Thread %02d: Expected Word offset = %03d\n", tid, extract_word_offset(expected)); + fprintf(f, "Thread %02d: Observed Word offset = %03d\n", tid, extract_word_offset(observed)); + fprintf(f, "Thread %02d: Expected sweep-id = 0x%x\n", tid, extract_sweep_id(expected)); + fprintf(f, "Thread %02d: Observed sweep-id = 0x%x\n", tid, extract_sweep_id(observed)); + fprintf(f, "----------------------------------------------------------\n"); +} + +static inline void end_verification_log(unsigned int tid, unsigned nr_anamolies) +{ + FILE *f = fp[tid]; + char logfile[30]; + char path[LOGDIR_NAME_SIZE + 30]; + char separator[] = "/"; + + fclose(f); + + if (nr_anamolies == 0) { + remove(path); + return; + } + + sprintf(logfile, logfilename, tid); + strcpy(path, logdir); + strcat(path, separator); + strcat(path, logfile); + + printf("Thread %02d chunk has %d corrupted words. For details check %s\n", + tid, nr_anamolies, path); +} + +/* + * When a COMPARE step of a rim-sequence fails, the rim_thread informs + * everyone else via the shared_memory pointed to by + * corruption_found variable. On seeing this, every thread verifies the + * content of its chunk as follows. + * + * Suppose a thread identified with @tid was about to store (but not + * yet stored) to @next_store_addr in its current sweep identified + * @cur_sweep_id. Let @prev_sweep_id indicate the previous sweep_id. + * + * This implies that for all the addresses @addr < @next_store_addr, + * Thread @tid has already performed a store as part of its current + * sweep. Hence we expect the content of such @addr to be: + * |-------------------------------------------------| + * | tid | word_offset(addr) | cur_sweep_id | + * |-------------------------------------------------| + * + * Since Thread @tid is yet to perform stores on address + * @next_store_addr and above, we expect the content of such an + * address @addr to be: + * |-------------------------------------------------| + * | tid | word_offset(addr) | prev_sweep_id | + * |-------------------------------------------------| + * + * The verifier function @verify_chunk does this verification and logs + * any anamolies that it finds. + */ +static void verify_chunk(unsigned int tid, unsigned int *next_store_addr, + unsigned int cur_sweep_id, + unsigned int prev_sweep_id) +{ + unsigned int *iter_ptr; + unsigned int size = RIM_CHUNK_SIZE; + unsigned int expected; + unsigned int observed; + char *chunk_start = compute_chunk_start_addr(tid); + + int nr_anamolies = 0; + + start_verification_log(tid, next_store_addr, + cur_sweep_id, prev_sweep_id); + + for (iter_ptr = (unsigned int *)chunk_start; + (unsigned long)iter_ptr < (unsigned long)chunk_start + size; + iter_ptr++) { + unsigned int expected_sweep_id; + + if (iter_ptr < next_store_addr) { + expected_sweep_id = cur_sweep_id; + } else { + expected_sweep_id = prev_sweep_id; + } + + expected = compute_store_pattern(tid, iter_ptr, expected_sweep_id); + + dcbf((volatile unsigned int*)iter_ptr); //Flush before reading + observed = *iter_ptr; + + if (observed != expected) { + nr_anamolies++; + log_anamoly(tid, iter_ptr, expected, observed); + } + } + + end_verification_log(tid, nr_anamolies); +} + +static void set_pthread_cpu(pthread_t th, int cpu) +{ + cpu_set_t run_cpu_mask; + struct sched_param param; + + CPU_ZERO(&run_cpu_mask); + CPU_SET(cpu, &run_cpu_mask); + pthread_setaffinity_np(th, sizeof(cpu_set_t), &run_cpu_mask); + + param.sched_priority = 1; + if (0 && sched_setscheduler(0, SCHED_FIFO, ¶m) == -1) { + /* haven't reproduced with this setting, it kills random preemption which may be a factor */ + fprintf(stderr, "could not set SCHED_FIFO, run as root?\n"); + } +} + +static void set_mycpu(int cpu) +{ + cpu_set_t run_cpu_mask; + struct sched_param param; + + CPU_ZERO(&run_cpu_mask); + CPU_SET(cpu, &run_cpu_mask); + sched_setaffinity(0, sizeof(cpu_set_t), &run_cpu_mask); + + param.sched_priority = 1; + if (0 && sched_setscheduler(0, SCHED_FIFO, ¶m) == -1) { + fprintf(stderr, "could not set SCHED_FIFO, run as root?\n"); + } +} + +static volatile int segv_wait; + +static void segv_handler(int signo, siginfo_t *info, void *extra) +{ + while (segv_wait) { + sched_yield(); + } + +} + +static void set_segv_handler(void) +{ + struct sigaction sa; + + sa.sa_flags = SA_SIGINFO; + sa.sa_sigaction = segv_handler; + + if (sigaction(SIGSEGV, &sa, NULL) == -1) { + perror("sigaction"); + exit(EXIT_FAILURE); + } +} + +int timeout = 0; +/* + * This function is executed by every rim_thread. + * + * This function performs sweeps over the exclusive chunks of the + * rim_threads executing the rim-sequence one word at a time. + */ +static void *rim_fn(void *arg) +{ + unsigned int tid = *((unsigned int *)arg); + + int size = RIM_CHUNK_SIZE; + char *chunk_start = compute_chunk_start_addr(tid); + + unsigned int prev_sweep_id; + unsigned int cur_sweep_id = 0; + + /* word access */ + unsigned int pattern = cur_sweep_id; + unsigned int *pattern_ptr = &pattern; + unsigned int *w_ptr, read_data; + + set_segv_handler(); + + /* + * Let us initialize the chunk: + * + * Each word-aligned address addr in the chunk, + * is initialized to : + * |-------------------------------------------------| + * | tid | word_offset(addr) | 0 | + * |-------------------------------------------------| + */ + for (w_ptr = (unsigned int *)chunk_start; + (unsigned long)w_ptr < (unsigned long)(chunk_start) + size; + w_ptr++) { + + *pattern_ptr = compute_store_pattern(tid, w_ptr, cur_sweep_id); + *w_ptr = *pattern_ptr; + } + + while (!corruption_found && !timeout) { + prev_sweep_id = cur_sweep_id; + cur_sweep_id = cur_sweep_id + 1; + + for (w_ptr = (unsigned int *)chunk_start; + (unsigned long)w_ptr < (unsigned long)(chunk_start) + size; + w_ptr++) { + unsigned int old_pattern; + + /* + * Compute the pattern that we would have + * stored at this location in the previous + * sweep. + */ + old_pattern = compute_store_pattern(tid, w_ptr, prev_sweep_id); + + /* + * FLUSH:Ensure that we flush the contents of + * the cache before loading + */ + dcbf((volatile unsigned int*)w_ptr); //Flush + + /* LOAD: Read the value */ + read_data = *w_ptr; //Load + + /* + * COMPARE: Is it the same as what we had stored + * in the previous sweep ? It better be! + */ + if (read_data != old_pattern) { + /* No it isn't! Tell everyone */ + corruption_found = 1; + } + + /* + * Before performing a store, let us check if + * any rim_thread has found a corruption. + */ + if (corruption_found || timeout) { + /* + * Yes. Someone (including us!) has found + * a corruption :( + * + * Let us verify that our chunk is + * correct. + */ + /* But first, let us allow the dust to settle down! */ + verify_chunk(tid, w_ptr, cur_sweep_id, prev_sweep_id); + + return 0; + } + + /* + * Compute the new pattern that we are going + * to write to this location + */ + *pattern_ptr = compute_store_pattern(tid, w_ptr, cur_sweep_id); + + /* + * STORE: Now let us write this pattern into + * the location + */ + *w_ptr = *pattern_ptr; + } + } + + return NULL; +} + + +static unsigned long start_cpu = 0; +static unsigned long nrthreads = 4; + +static pthread_t mem_snapshot_thread; + +static void *mem_snapshot_fn(void *arg) +{ + int page_size = getpagesize(); + size_t size = page_size; + void *tmp = malloc(size); + + while (!corruption_found && !timeout) { + /* Stop memory migration once corruption is found */ + segv_wait = 1; + + mprotect(map1, size, PROT_READ); + + /* + * Load from the working alias (map1). Loading from map2 + * also fails. + */ + memcpy(tmp, map1, size); + + /* + * Stores must go via map2 which has write permissions, but + * the corrupted data tends to be seen in the snapshot buffer, + * so corruption does not appear to be introduced at the + * copy-back via map2 alias here. + */ + memcpy(map2, tmp, size); + /* + * Before releasing other threads, must ensure the copy + * back to + */ + asm volatile("sync" ::: "memory"); + mprotect(map1, size, PROT_READ|PROT_WRITE); + asm volatile("sync" ::: "memory"); + segv_wait = 0; + + usleep(1); /* This value makes a big difference */ + } + + return 0; +} + +void alrm_sighandler(int sig) +{ + timeout = 1; +} + +int main(int argc, char *argv[]) +{ + int c; + int page_size = getpagesize(); + time_t now; + int i, dir_error; + pthread_attr_t attr; + key_t shm_key = (key_t) getpid(); + int shmid, run_time = 20 * 60; + struct sigaction sa_alrm; + + snprintf(logdir, LOGDIR_NAME_SIZE, + "/tmp/logdir-%u", (unsigned int)getpid()); + while ((c = getopt(argc, argv, "r:hn:l:t:")) != -1) { + switch(c) { + case 'r': + start_cpu = strtoul(optarg, NULL, 10); + break; + case 'h': + printf("%s [-r <start_cpu>] [-n <nrthreads>] [-l <logdir>] [-t <timeout>]\n", argv[0]); + exit(0); + break; + case 'n': + nrthreads = strtoul(optarg, NULL, 10); + break; + case 'l': + strncpy(logdir, optarg, LOGDIR_NAME_SIZE - 1); + break; + case 't': + run_time = strtoul(optarg, NULL, 10); + break; + default: + printf("invalid option\n"); + exit(0); + break; + } + } + + if (nrthreads > MAX_THREADS) + nrthreads = MAX_THREADS; + + shmid = shmget(shm_key, page_size, IPC_CREAT|0666); + if (shmid < 0) { + err_msg("Failed shmget\n"); + } + + map1 = shmat(shmid, NULL, 0); + if (map1 == (void *) -1) { + err_msg("Failed shmat"); + } + + map2 = shmat(shmid, NULL, 0); + if (map2 == (void *) -1) { + err_msg("Failed shmat"); + } + + dir_error = mkdir(logdir, 0755); + + if (dir_error) { + err_msg("Failed mkdir"); + } + + printf("start_cpu list:%lu\n", start_cpu); + printf("number of worker threads:%lu + 1 snapshot thread\n", nrthreads); + printf("Allocated address:0x%016lx + secondary map:0x%016lx\n", (unsigned long)map1, (unsigned long)map2); + printf("logdir at : %s\n", logdir); + printf("Timeout: %d seconds\n", run_time); + + time(&now); + printf("=================================\n"); + printf(" Starting Test\n"); + printf(" %s", ctime(&now)); + printf("=================================\n"); + + for (i = 0; i < nrthreads; i++) { + if (1 && !fork()) { + prctl(PR_SET_PDEATHSIG, SIGKILL); + set_mycpu(start_cpu + i); + for (;;) + sched_yield(); + exit(0); + } + } + + + sa_alrm.sa_handler = &alrm_sighandler; + sigemptyset(&sa_alrm.sa_mask); + sa_alrm.sa_flags = 0; + + if (sigaction(SIGALRM, &sa_alrm, 0) == -1) { + err_msg("Failed signal handler registration\n"); + } + + alarm(run_time); + + pthread_attr_init(&attr); + for (i = 0; i < nrthreads; i++) { + rim_thread_ids[i] = i; + pthread_create(&rim_threads[i], &attr, rim_fn, &rim_thread_ids[i]); + set_pthread_cpu(rim_threads[i], start_cpu + i); + } + + pthread_create(&mem_snapshot_thread, &attr, mem_snapshot_fn, map1); + set_pthread_cpu(mem_snapshot_thread, start_cpu + i); + + + pthread_join(mem_snapshot_thread, NULL); + for (i = 0; i < nrthreads; i++) { + pthread_join(rim_threads[i], NULL); + } + + if (!timeout) { + time(&now); + printf("=================================\n"); + printf(" Data Corruption Detected\n"); + printf(" %s", ctime(&now)); + printf(" See logfiles in %s\n", logdir); + printf("=================================\n"); + return 1; + } + return 0; +} |