diff options
| -rw-r--r-- | lib/maple_tree.c | 7 | ||||
| -rw-r--r-- | mm/huge_memory.c | 2 | ||||
| -rw-r--r-- | mm/madvise.c | 6 | ||||
| -rw-r--r-- | mm/shmem.c | 6 | ||||
| -rw-r--r-- | tools/testing/selftests/cachestat/test_cachestat.c | 80 |
5 files changed, 80 insertions, 21 deletions
diff --git a/lib/maple_tree.c b/lib/maple_tree.c index ffb9d15bd815..05d5db255c39 100644 --- a/lib/maple_tree.c +++ b/lib/maple_tree.c @@ -4107,6 +4107,10 @@ static inline unsigned char mas_wr_new_end(struct ma_wr_state *wr_mas) * mas_wr_append: Attempt to append * @wr_mas: the maple write state * + * This is currently unsafe in rcu mode since the end of the node may be cached + * by readers while the node contents may be updated which could result in + * inaccurate information. + * * Return: True if appended, false otherwise */ static inline bool mas_wr_append(struct ma_wr_state *wr_mas, @@ -4116,6 +4120,9 @@ static inline bool mas_wr_append(struct ma_wr_state *wr_mas, struct ma_state *mas = wr_mas->mas; unsigned char node_pivots = mt_pivots[wr_mas->type]; + if (mt_in_rcu(mas->tree)) + return false; + if (mas->offset != wr_mas->node_end) return false; diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 213bb1e33830..cb4432792b88 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -1607,7 +1607,7 @@ bool madvise_free_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma, * If other processes are mapping this folio, we couldn't discard * the folio unless they all do MADV_FREE so let's skip the folio. */ - if (folio_mapcount(folio) != 1) + if (folio_estimated_sharers(folio) != 1) goto out; if (!folio_trylock(folio)) diff --git a/mm/madvise.c b/mm/madvise.c index 1fb2a11d77d9..b1f53a95e3a5 100644 --- a/mm/madvise.c +++ b/mm/madvise.c @@ -383,7 +383,7 @@ static int madvise_cold_or_pageout_pte_range(pmd_t *pmd, folio = pfn_folio(pmd_pfn(orig_pmd)); /* Do not interfere with other mappings of this folio */ - if (folio_mapcount(folio) != 1) + if (folio_estimated_sharers(folio) != 1) goto huge_unlock; if (pageout_anon_only_filter && !folio_test_anon(folio)) @@ -459,7 +459,7 @@ regular_folio: if (folio_test_large(folio)) { int err; - if (folio_mapcount(folio) != 1) + if (folio_estimated_sharers(folio) != 1) break; if (pageout_anon_only_filter && !folio_test_anon(folio)) break; @@ -683,7 +683,7 @@ static int madvise_free_pte_range(pmd_t *pmd, unsigned long addr, if (folio_test_large(folio)) { int err; - if (folio_mapcount(folio) != 1) + if (folio_estimated_sharers(folio) != 1) break; if (!folio_trylock(folio)) break; diff --git a/mm/shmem.c b/mm/shmem.c index 20daa207d8bf..99fb60ec2c3d 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -806,14 +806,16 @@ unsigned long shmem_partial_swap_usage(struct address_space *mapping, XA_STATE(xas, &mapping->i_pages, start); struct page *page; unsigned long swapped = 0; + unsigned long max = end - 1; rcu_read_lock(); - xas_for_each(&xas, page, end - 1) { + xas_for_each(&xas, page, max) { if (xas_retry(&xas, page)) continue; if (xa_is_value(page)) swapped++; - + if (xas.xa_index == max) + break; if (need_resched()) { xas_pause(&xas); cond_resched_rcu(); diff --git a/tools/testing/selftests/cachestat/test_cachestat.c b/tools/testing/selftests/cachestat/test_cachestat.c index 54d09b820ed4..c037553cfd92 100644 --- a/tools/testing/selftests/cachestat/test_cachestat.c +++ b/tools/testing/selftests/cachestat/test_cachestat.c @@ -4,10 +4,12 @@ #include <stdio.h> #include <stdbool.h> #include <linux/kernel.h> +#include <linux/magic.h> #include <linux/mman.h> #include <sys/mman.h> #include <sys/shm.h> #include <sys/syscall.h> +#include <sys/vfs.h> #include <unistd.h> #include <string.h> #include <fcntl.h> @@ -15,6 +17,8 @@ #include "../kselftest.h" +#define NR_TESTS 9 + static const char * const dev_files[] = { "/dev/zero", "/dev/null", "/dev/urandom", "/proc/version", "/proc" @@ -91,19 +95,33 @@ out: } /* + * fsync() is implemented via noop_fsync() on tmpfs. This makes the fsync() + * test fail below, so we need to check for test file living on a tmpfs. + */ +static bool is_on_tmpfs(int fd) +{ + struct statfs statfs_buf; + + if (fstatfs(fd, &statfs_buf)) + return false; + + return statfs_buf.f_type == TMPFS_MAGIC; +} + +/* * Open/create the file at filename, (optionally) write random data to it * (exactly num_pages), then test the cachestat syscall on this file. * * If test_fsync == true, fsync the file, then check the number of dirty * pages. */ -bool test_cachestat(const char *filename, bool write_random, bool create, - bool test_fsync, unsigned long num_pages, int open_flags, - mode_t open_mode) +static int test_cachestat(const char *filename, bool write_random, bool create, + bool test_fsync, unsigned long num_pages, + int open_flags, mode_t open_mode) { size_t PS = sysconf(_SC_PAGESIZE); int filesize = num_pages * PS; - bool ret = true; + int ret = KSFT_PASS; long syscall_ret; struct cachestat cs; struct cachestat_range cs_range = { 0, filesize }; @@ -112,7 +130,7 @@ bool test_cachestat(const char *filename, bool write_random, bool create, if (fd == -1) { ksft_print_msg("Unable to create/open file.\n"); - ret = false; + ret = KSFT_FAIL; goto out; } else { ksft_print_msg("Create/open %s\n", filename); @@ -121,7 +139,7 @@ bool test_cachestat(const char *filename, bool write_random, bool create, if (write_random) { if (!write_exactly(fd, filesize)) { ksft_print_msg("Unable to access urandom.\n"); - ret = false; + ret = KSFT_FAIL; goto out1; } } @@ -132,7 +150,7 @@ bool test_cachestat(const char *filename, bool write_random, bool create, if (syscall_ret) { ksft_print_msg("Cachestat returned non-zero.\n"); - ret = false; + ret = KSFT_FAIL; goto out1; } else { @@ -142,15 +160,17 @@ bool test_cachestat(const char *filename, bool write_random, bool create, if (cs.nr_cache + cs.nr_evicted != num_pages) { ksft_print_msg( "Total number of cached and evicted pages is off.\n"); - ret = false; + ret = KSFT_FAIL; } } } if (test_fsync) { - if (fsync(fd)) { + if (is_on_tmpfs(fd)) { + ret = KSFT_SKIP; + } else if (fsync(fd)) { ksft_print_msg("fsync fails.\n"); - ret = false; + ret = KSFT_FAIL; } else { syscall_ret = syscall(cachestat_nr, fd, &cs_range, &cs, 0); @@ -161,13 +181,13 @@ bool test_cachestat(const char *filename, bool write_random, bool create, print_cachestat(&cs); if (cs.nr_dirty) { - ret = false; + ret = KSFT_FAIL; ksft_print_msg( "Number of dirty should be zero after fsync.\n"); } } else { ksft_print_msg("Cachestat (after fsync) returned non-zero.\n"); - ret = false; + ret = KSFT_FAIL; goto out1; } } @@ -236,13 +256,29 @@ out: int main(void) { - int ret = 0; + int ret; + + ksft_print_header(); + + ret = syscall(__NR_cachestat, -1, NULL, NULL, 0); + if (ret == -1 && errno == ENOSYS) + ksft_exit_skip("cachestat syscall not available\n"); + + ksft_set_plan(NR_TESTS); + + if (ret == -1 && errno == EBADF) { + ksft_test_result_pass("bad file descriptor recognized\n"); + ret = 0; + } else { + ksft_test_result_fail("bad file descriptor ignored\n"); + ret = 1; + } for (int i = 0; i < 5; i++) { const char *dev_filename = dev_files[i]; if (test_cachestat(dev_filename, false, false, false, - 4, O_RDONLY, 0400)) + 4, O_RDONLY, 0400) == KSFT_PASS) ksft_test_result_pass("cachestat works with %s\n", dev_filename); else { ksft_test_result_fail("cachestat fails with %s\n", dev_filename); @@ -251,13 +287,27 @@ int main(void) } if (test_cachestat("tmpfilecachestat", true, true, - true, 4, O_CREAT | O_RDWR, 0400 | 0600)) + false, 4, O_CREAT | O_RDWR, 0600) == KSFT_PASS) ksft_test_result_pass("cachestat works with a normal file\n"); else { ksft_test_result_fail("cachestat fails with normal file\n"); ret = 1; } + switch (test_cachestat("tmpfilecachestat", true, true, + true, 4, O_CREAT | O_RDWR, 0600)) { + case KSFT_FAIL: + ksft_test_result_fail("cachestat fsync fails with normal file\n"); + ret = KSFT_FAIL; + break; + case KSFT_PASS: + ksft_test_result_pass("cachestat fsync works with a normal file\n"); + break; + case KSFT_SKIP: + ksft_test_result_skip("tmpfilecachestat is on tmpfs\n"); + break; + } + if (test_cachestat_shmem()) ksft_test_result_pass("cachestat works with a shmem file\n"); else { |