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| author | Sven Schnelle <svens@linux.ibm.com> | 2026-09-09 11:29:53 +0200 |
|---|---|---|
| committer | Masami Hiramatsu (Google) <mhiramat@kernel.org> | 2026-09-10 08:43:35 +0900 |
| commit | d22c3e0088e85be8131f7a9283f759cdbb20726d (patch) | |
| tree | 9668df2aa27b26f850d3ba5ba1287e443803675c /drivers/md/dm-vdo/cpu.h | |
| download | linux-stable-d22c3e0088e85be8131f7a9283f759cdbb20726d.tar.gz linux-stable-d22c3e0088e85be8131f7a9283f759cdbb20726d.zip | |
selftests/ftrace: Fix unique symbol check in kprobe_non_uniq_symbol.tcgrafted
The current regex also matches symbols in modules, which makes the
test fail on s390 where name_show is present only once in the kernel,
but also multiple times in modules:
000001b1401cdc20 t name_show
000001b0c05e6c40 t name_show [mdev]
000001b0c0495f30 t name_show [i2c_core]
Fix this by changing the regular expression to only match the function
name.
Link: https://lore.kernel.org/all/20260909092954.2200558-1-svens@linux.ibm.com/
Fixes: 03b80ff8023a ("selftests/ftrace: Add new test case which checks non unique symbol")
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Diffstat (limited to 'drivers/md/dm-vdo/cpu.h')
| -rw-r--r-- | drivers/md/dm-vdo/cpu.h | 59 |
1 files changed, 59 insertions, 0 deletions
diff --git a/drivers/md/dm-vdo/cpu.h b/drivers/md/dm-vdo/cpu.h new file mode 100644 index 000000000..d6a2615ba --- /dev/null +++ b/drivers/md/dm-vdo/cpu.h @@ -0,0 +1,59 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright 2023 Red Hat + */ + +#ifndef UDS_CPU_H +#define UDS_CPU_H + +#include <linux/cache.h> + +/** + * uds_prefetch_address() - Minimize cache-miss latency by attempting to move data into a CPU cache + * before it is accessed. + * + * @address: the address to fetch (may be invalid) + * @for_write: must be constant at compile time--false if for reading, true if for writing + */ +static inline void uds_prefetch_address(const void *address, bool for_write) +{ + /* + * for_write won't be a constant if we are compiled with optimization turned off, in which + * case prefetching really doesn't matter. clang can't figure out that if for_write is a + * constant, it can be passed as the second, mandatorily constant argument to prefetch(), + * at least currently on llvm 12. + */ + if (__builtin_constant_p(for_write)) { + if (for_write) + __builtin_prefetch(address, true); + else + __builtin_prefetch(address, false); + } +} + +/** + * uds_prefetch_range() - Minimize cache-miss latency by attempting to move a range of addresses + * into a CPU cache before they are accessed. + * + * @start: the starting address to fetch (may be invalid) + * @size: the number of bytes in the address range + * @for_write: must be constant at compile time--false if for reading, true if for writing + */ +static inline void uds_prefetch_range(const void *start, unsigned int size, + bool for_write) +{ + /* + * Count the number of cache lines to fetch, allowing for the address range to span an + * extra cache line boundary due to address alignment. + */ + const char *address = (const char *) start; + unsigned int offset = ((uintptr_t) address % L1_CACHE_BYTES); + unsigned int cache_lines = (1 + ((size + offset) / L1_CACHE_BYTES)); + + while (cache_lines-- > 0) { + uds_prefetch_address(address, for_write); + address += L1_CACHE_BYTES; + } +} + +#endif /* UDS_CPU_H */ |
