mdbx: conditionally use cacheflush() for linux < 2.6.11

Change-Id: Id34c67797e14f709f767bf1b687319cd2dfef874
This commit is contained in:
Leonid Yuriev 2019-07-22 00:19:15 +03:00
parent a6bad26e1d
commit 663f3f3c58
3 changed files with 47 additions and 10 deletions

View File

@ -19,6 +19,7 @@
#endif
#include "./bits.h"
#include <sys/utsname.h>
/* Some platforms define the EOWNERDEAD error code
* even though they don't support Robust Mutexes.
@ -36,10 +37,31 @@
#endif
#endif /* MDBX_USE_ROBUST */
uint32_t linux_kernel_version;
/*----------------------------------------------------------------------------*/
/* rthc */
static __cold __attribute__((constructor)) void mdbx_global_constructor(void) {
struct utsname buffer;
if (uname(&buffer) == 0) {
int i = 0;
char *p = buffer.release;
while (*p && i < 4) {
if (*p >= '0' && *p <= '9') {
long number = strtol(p, &p, 10);
if (number > 0) {
if (number > 255)
number = 255;
linux_kernel_version += number << (24 - i * 8);
}
++i;
} else {
++p;
}
}
}
mdbx_rthc_global_init();
}

View File

@ -4639,9 +4639,17 @@ static int mdbx_page_flush(MDBX_txn *txn, pgno_t keep) {
mdbx_debug("Write error: %s", mdbx_strerror(rc));
return rc;
}
#if MDBX_CPU_CACHE_MMAP_NONCOHERENT == 1
mdbx_invalidate_mmap_noncoherent_cache(env->me_map + wpos, wsize);
#endif
#if MDBX_CPU_CACHE_MMAP_NONCOHERENT
#if defined(__linux__) || defined(__gnu_linux__)
if (linux_kernel_version >= 0x02060b00)
/* Linux kernels older than version 2.6.11 ignore the addr and nbytes
* arguments, making this function fairly expensive. Therefore, the
* whole cache is always flushed. */
#endif /* Linux */
mdbx_invalidate_mmap_noncoherent_cache(env->me_map + wpos, wsize);
#endif /* MDBX_CPU_CACHE_MMAP_NONCOHERENT */
n = 0;
}
if (i > pagecount)
@ -4657,13 +4665,16 @@ static int mdbx_page_flush(MDBX_txn *txn, pgno_t keep) {
n++;
}
#if MDBX_CPU_CACHE_MMAP_NONCOHERENT > 1
/* Linux kernels older than version 2.6.11 ignore the addr and nbytes
* arguments, making this function fairly expensive. Therefore, the whole
* cache is always flushed. */
mdbx_invalidate_mmap_noncoherent_cache(env->me_map,
pgno2bytes(env, txn->mt_next_pgno));
#endif
#if MDBX_CPU_CACHE_MMAP_NONCOHERENT && \
(defined(__linux__) || defined(__gnu_linux__))
if (linux_kernel_version < 0x02060b00) {
/* Linux kernels older than version 2.6.11 ignore the addr and nbytes
* arguments, making this function fairly expensive. Therefore, the whole
* cache is always flushed. */
mdbx_invalidate_mmap_noncoherent_cache(env->me_map,
pgno2bytes(env, txn->mt_next_pgno));
}
#endif /* MDBX_CPU_CACHE_MMAP_NONCOHERENT && Linux */
for (i = keep; ++i <= pagecount;) {
dp = dl[i].ptr;

View File

@ -462,6 +462,10 @@ int mdbx_vasprintf(char **strp, const char *fmt, va_list ap);
/* max bytes to write in one call */
#define MAX_WRITE UINT32_C(0x3fff0000)
#if defined(__linux__) || defined(__gnu_linux__)
extern uint32_t linux_kernel_version;
#endif /* Linux */
/* Get the size of a memory page for the system.
* This is the basic size that the platform's memory manager uses, and is
* fundamental to the use of memory-mapped files. */