Re: [PATCH v5 1/8] smp: Introduce a generic on_each_cpu_mask function

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Tue, 03 Jan 2012 23:26:24 +0100, Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> wrote:

On Mon,  2 Jan 2012 12:24:12 +0200
Gilad Ben-Yossef <gilad@xxxxxxxxxxxxx> wrote:

on_each_cpu_mask calls a function on processors specified my cpumask,
which may include the local processor.

@@ -132,6 +139,15 @@ static inline int up_smp_call_function(smp_call_func_t func, void *info)
 		local_irq_enable();		\
 		0;				\
 	})
+#define on_each_cpu_mask(mask, func, info, wait) \
+	do {						\
+		if (cpumask_test_cpu(0, (mask))) {	\
+			local_irq_disable();		\
+			(func)(info);			\
+			local_irq_enable();		\
+		}					\
+	} while (0)

Why is the cpumask_test_cpu() call there?  It's hard to think of a
reason why "mask" would specify any CPU other than "0" in a
uniprocessor kernel.

It may specify none.  For instance, in drain_all_pages() case, if the
CPU has no pages on PCP lists, the mask will be empty and so the
cpumask_test_cpu() will return zero.

--
Best regards,                                         _     _
.o. | Liege of Serenely Enlightened Majesty of      o' \,=./ `o
..o | Computer Science,  Michał “mina86” Nazarewicz    (o o)
ooo +----<email/xmpp: mpn@xxxxxxxxxx>--------------ooO--(_)--Ooo--
--
To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html


[Index of Archives]     [Linux Ext4 Filesystem]     [Union Filesystem]     [Filesystem Testing]     [Ceph Users]     [Ecryptfs]     [AutoFS]     [Kernel Newbies]     [Share Photos]     [Security]     [Netfilter]     [Bugtraq]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux Cachefs]     [Reiser Filesystem]     [Linux RAID]     [Samba]     [Device Mapper]     [CEPH Development]
  Powered by Linux