diff options
Diffstat (limited to 'mysys/my_largepage.c')
| -rw-r--r-- | mysys/my_largepage.c | 167 |
1 files changed, 167 insertions, 0 deletions
diff --git a/mysys/my_largepage.c b/mysys/my_largepage.c new file mode 100644 index 00000000000..0639c360b46 --- /dev/null +++ b/mysys/my_largepage.c @@ -0,0 +1,167 @@ +/* Copyright (C) 2004 MySQL AB + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program 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 General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ + +#include "mysys_priv.h" + +#ifdef HAVE_LARGE_PAGES + +#ifdef HAVE_SYS_IPC_H +#include <sys/ipc.h> +#endif + +#ifdef HAVE_SYS_SHM_H +#include <sys/shm.h> +#endif + +static uint my_get_large_page_size_int(void); +static gptr my_large_malloc_int(uint size, myf my_flags); +static my_bool my_large_free_int(gptr ptr, myf my_flags); + +/* Gets the size of large pages from the OS */ + +uint my_get_large_page_size(void) +{ + uint size; + DBUG_ENTER("my_get_large_page_size"); + + if (!(size = my_get_large_page_size_int())) + fprintf(stderr, "Warning: Failed to determine large page size\n"); + + DBUG_RETURN(size); +} + +/* + General large pages allocator. + Tries to allocate memory from large pages pool and falls back to + my_malloc_lock() in case of failure +*/ + +gptr my_large_malloc(uint size, myf my_flags) +{ + gptr ptr; + DBUG_ENTER("my_large_malloc"); + + if (my_use_large_pages && my_large_page_size) + { + if ((ptr = my_large_malloc_int(size, my_flags)) != NULL) + DBUG_RETURN(ptr); + if (my_flags & MY_WME) + fprintf(stderr, "Warning: Using conventional memory pool\n"); + } + + DBUG_RETURN(my_malloc_lock(size, my_flags)); +} + +/* + General large pages deallocator. + Tries to deallocate memory as if it was from large pages pool and falls back + to my_free_lock() in case of failure + */ + +void my_large_free(gptr ptr, myf my_flags __attribute__((unused))) +{ + DBUG_ENTER("my_large_free"); + + /* + my_large_free_int() can only fail if ptr was not allocated with + my_large_malloc_int(), i.e. my_malloc_lock() was used so we should free it + with my_free_lock() + */ + if (!my_use_large_pages || !my_large_page_size || + !my_large_free_int(ptr, my_flags)) + my_free_lock(ptr, my_flags); + + DBUG_VOID_RETURN; +} + +#ifdef HUGETLB_USE_PROC_MEMINFO +/* Linux-specific function to determine the size of large pages */ + +uint my_get_large_page_size_int(void) +{ + FILE *f; + uint size = 0; + char buf[256]; + DBUG_ENTER("my_get_large_page_size_int"); + + if (!(f = my_fopen("/proc/meminfo", O_RDONLY, MYF(MY_WME)))) + goto finish; + + while (fgets(buf, sizeof(buf), f)) + if (sscanf(buf, "Hugepagesize: %u kB", &size)) + break; + + my_fclose(f, MYF(MY_WME)); + +finish: + DBUG_RETURN(size * 1024); +} +#endif /* HUGETLB_USE_PROC_MEMINFO */ + +#if HAVE_DECL_SHM_HUGETLB +/* Linux-specific large pages allocator */ + +gptr my_large_malloc_int(uint size, myf my_flags) +{ + int shmid; + gptr ptr; + struct shmid_ds buf; + DBUG_ENTER("my_large_malloc_int"); + + /* Align block size to my_large_page_size */ + size = ((size - 1) & ~(my_large_page_size - 1)) + my_large_page_size; + + shmid = shmget(IPC_PRIVATE, (size_t)size, SHM_HUGETLB | SHM_R | SHM_W); + if (shmid < 0) + { + if (my_flags & MY_WME) + fprintf(stderr, + "Warning: Failed to allocate %d bytes from HugeTLB memory." + " errno %d\n", size, errno); + + DBUG_RETURN(NULL); + } + + ptr = shmat(shmid, NULL, 0); + if (ptr == (void *)-1) + { + if (my_flags& MY_WME) + fprintf(stderr, "Warning: Failed to attach shared memory segment," + " errno %d\n", errno); + shmctl(shmid, IPC_RMID, &buf); + + DBUG_RETURN(NULL); + } + + /* + Remove the shared memory segment so that it will be automatically freed + after memory is detached or process exits + */ + shmctl(shmid, IPC_RMID, &buf); + + DBUG_RETURN(ptr); +} + +/* Linux-specific large pages deallocator */ + +my_bool my_large_free_int(byte *ptr, myf my_flags __attribute__((unused))) +{ + DBUG_ENTER("my_large_free_int"); + DBUG_RETURN(shmdt(ptr) == 0); +} +#endif /* HAVE_DECL_SHM_HUGETLB */ + +#endif /* HAVE_LARGE_PAGES */ |