x86/mce: Make timer handling more robust

Erik reported that on a preproduction hardware a CMCI storm triggers the
BUG_ON in add_timer_on(). The reason is that the per CPU MCE timer is
started by the CMCI logic before the MCE CPU hotplug callback starts the
timer with add_timer_on(). So the timer is already queued which triggers
the BUG.

Using add_timer_on() is pretty pointless in this code because the timer is
strictlty per CPU, initialized as pinned and all operations which arm the
timer happen on the CPU to which the timer belongs.

Simplify the whole machinery by using mod_timer() instead of add_timer_on()
which avoids the problem because mod_timer() can handle already queued
timers. Use __start_timer() everywhere so the earliest armed expiry time is
preserved.

Reported-by: Erik Veijola <erik.veijola@intel.com>
Tested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1701310936080.3457@nanos
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

path: root/trie.h

#ifndef TRIE_H
#define TRIE_H

#include <netinet/in.h>

extern void trie_addr_lookup(char *buff, size_t len, int ipv4, int *fd,
			     struct sockaddr_storage *addr, size_t *alen);
extern int trie_addr_maybe_update(char *buff, size_t len, int ipv4, int fd,
				  struct sockaddr_storage *addr, size_t alen);
extern void trie_addr_remove(int fd);
extern void trie_addr_remove_addr(struct sockaddr_storage *addr, size_t alen);
extern void trie_init(void);
extern void trie_cleanup(void);

#endif /* TRIE_H */