diff options
| author | Rafael J. Wysocki | 2006-09-25 23:32:48 -0700 |
|---|---|---|
| committer | Linus Torvalds | 2006-09-26 08:48:59 -0700 |
| commit | e3920fb42c8ddfe63befb54d95c0e13eabacea9b (patch) | |
| tree | 08371a71e58e6e9d3ec62dfa6a22b3b5e6ff0fd5 /kernel/power/main.c | |
| parent | e8eff5ac294e12531c4195e0c15a222d3c9015e5 (diff) | |
[PATCH] Disable CPU hotplug during suspend
The current suspend code has to be run on one CPU, so we use the CPU
hotplug to take the non-boot CPUs offline on SMP machines. However, we
should also make sure that these CPUs will not be enabled by someone else
after we have disabled them.
The functions disable_nonboot_cpus() and enable_nonboot_cpus() are moved to
kernel/cpu.c, because they now refer to some stuff in there that should
better be static. Also it's better if disable_nonboot_cpus() returns an
error instead of panicking if something goes wrong, and
enable_nonboot_cpus() has no reason to panic(), because the CPUs may have
been enabled by the userland before it tries to take them online.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'kernel/power/main.c')
| -rw-r--r-- | kernel/power/main.c | 10 |
1 files changed, 4 insertions, 6 deletions
diff --git a/kernel/power/main.c b/kernel/power/main.c index 6d295c776794..4d403323a7bb 100644 --- a/kernel/power/main.c +++ b/kernel/power/main.c @@ -16,6 +16,7 @@ #include <linux/init.h> #include <linux/pm.h> #include <linux/console.h> +#include <linux/cpu.h> #include "power.h" @@ -51,7 +52,7 @@ void pm_set_ops(struct pm_ops * ops) static int suspend_prepare(suspend_state_t state) { - int error = 0; + int error; unsigned int free_pages; if (!pm_ops || !pm_ops->enter) @@ -59,12 +60,9 @@ static int suspend_prepare(suspend_state_t state) pm_prepare_console(); - disable_nonboot_cpus(); - - if (num_online_cpus() != 1) { - error = -EPERM; + error = disable_nonboot_cpus(); + if (error) goto Enable_cpu; - } if (freeze_processes()) { error = -EAGAIN; |