From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matthew Wilcox Date: Mon, 22 Nov 2004 16:07:05 +0000 Subject: Re: scalability of signal delivery for Posix Threads Message-Id: <20041122160705.GG25636@parcelfarce.linux.theplanet.co.uk> List-Id: References: <41A20AF3.9030408@sgi.com> In-Reply-To: <41A20AF3.9030408@sgi.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Ray Bryant Cc: Kernel Mailing List , "linux-ia64@vger.kernel.org" , lse-tech , holt@sgi.com, Dean Roe , Brian Sumner , John Hawkes On Mon, Nov 22, 2004 at 09:51:15AM -0600, Ray Bryant wrote: > Since signals are sent much more often than sigaction() is called, it would > seem to make more sense to make sigaction() take a heavier weight lock of > some kind (to update the signal handler decription) and to have the signal > delivery mechanism take a lighter weight lock. Making > current->sighand->siglock a rwlock_t really doesn't improve the situation > much, since cache line contention is just a severe in that case (if not > worse) than it is with the current definition. What about RCU or seqlock? -- "Next the statesmen will invent cheap lies, putting the blame upon the nation that is attacked, and every man will be glad of those conscience-soothing falsities, and will diligently study them, and refuse to examine any refutations of them; and thus he will by and by convince himself that the war is just, and will thank God for the better sleep he enjoys after this process of grotesque self-deception." -- Mark Twain