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| author | Eric Dumazet <dada1@cosmosbay.com> | 2006-03-23 03:01:04 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-03-23 07:38:17 -0800 |
| commit | 63872f87a151413100678f110d1556026002809e (patch) | |
| tree | 4abb8b8c7f60a9d2c6645c4eb9e95a9c6ba56023 /init/main.c | |
| parent | 5a6b7951bfcca7f45f44269ea87417c74558daf8 (diff) | |
| download | lwn-63872f87a151413100678f110d1556026002809e.tar.gz lwn-63872f87a151413100678f110d1556026002809e.zip | |
[PATCH] Only allocate percpu data for possible CPUs
percpu_data blindly allocates bootmem memory to store NR_CPUS instances of
cpudata, instead of allocating memory only for possible cpus.
This patch saves ram, allocating num_possible_cpus() (instead of NR_CPUS)
instances.
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Acked-by: "David S. Miller" <davem@davemloft.net>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: Jens Axboe <axboe@suse.de>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Jens Axboe <axboe@suse.de>
Cc: Anton Blanchard <anton@samba.org>
Acked-by: William Irwin <wli@holomorphy.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'init/main.c')
| -rw-r--r-- | init/main.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/init/main.c b/init/main.c index 141e8896d252..9cf6b307bfd7 100644 --- a/init/main.c +++ b/init/main.c @@ -333,6 +333,7 @@ static void __init setup_per_cpu_areas(void) { unsigned long size, i; char *ptr; + unsigned long nr_possible_cpus = num_possible_cpus(); /* Copy section for each CPU (we discard the original) */ size = ALIGN(__per_cpu_end - __per_cpu_start, SMP_CACHE_BYTES); @@ -340,12 +341,16 @@ static void __init setup_per_cpu_areas(void) if (size < PERCPU_ENOUGH_ROOM) size = PERCPU_ENOUGH_ROOM; #endif + ptr = alloc_bootmem(size * nr_possible_cpus); - ptr = alloc_bootmem(size * NR_CPUS); - - for (i = 0; i < NR_CPUS; i++, ptr += size) { + for (i = 0; i < NR_CPUS; i++) { + if (!cpu_possible(i)) { + __per_cpu_offset[i] = (char*)0 - __per_cpu_start; + continue; + } __per_cpu_offset[i] = ptr - __per_cpu_start; memcpy(ptr, __per_cpu_start, __per_cpu_end - __per_cpu_start); + ptr += size; } } #endif /* !__GENERIC_PER_CPU */ |