#ifndef _HWBM_H
#define _HWBM_H
struct hwbm_pool {
/* Capacity of the pool */
int size;
/* Size of the buffers managed */
int frag_size;
/* Number of buffers currently used by this pool */
int buf_num;
/* constructor called during alocation */
int (*construct)(struct hwbm_pool *bm_pool, void *buf);
/* protect acces to the buffer counter*/
spinlock_t lock;
/* private data */
void *priv;
};
#ifdef CONFIG_HWBM
void hwbm_buf_free(struct hwbm_pool *bm_pool, void *buf);
int hwbm_pool_refill(struct hwbm_pool *bm_pool, gfp_t gfp);
int hwbm_pool_add(struct hwbm_pool *bm_pool, unsigned int buf_num, gfp_t gfp);
#else
void hwbm_buf_free(struct hwbm_pool *bm_pool, void *buf) {}
int hwbm_pool_refill(struct hwbm_pool *bm_pool, gfp_t gfp) { return 0; }
int hwbm_pool_add(struct hwbm_pool *bm_pool, unsigned int buf_num, gfp_t gfp)
{ return 0; }
#endif /* CONFIG_HWBM */
#endif /* _HWBM_H */
ue='64679e565a4a099c5d5dc2ecf103dcaf039ef8c7'/>
Commit a389fcfd2cb5 ("Drivers: hv: vmbus: Fix signaling logic in
hv_need_to_signal_on_read()")
added the proper mb(), but removed the test "prev_write_sz < pending_sz"
when making the signal decision.
As a result, the guest can signal the host unnecessarily,
and then the host can throttle the guest because the host
thinks the guest is buggy or malicious; finally the user
running stress test can perceive intermittent freeze of
the guest.
This patch brings back the test, and properly handles the
in-place consumption APIs used by NetVSC (see get_next_pkt_raw(),
put_pkt_raw() and commit_rd_index()).
Fixes: a389fcfd2cb5 ("Drivers: hv: vmbus: Fix signaling logic in
hv_need_to_signal_on_read()")
Signed-off-by: Dexuan Cui <decui@microsoft.com>
Reported-by: Rolf Neugebauer <rolf.neugebauer@docker.com>
Tested-by: Rolf Neugebauer <rolf.neugebauer@docker.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>