ipn/ipnlocal: remember last notified taildrive shares and only notify if they've changed

Fixes #13195

Signed-off-by: Percy Wegmann <percy@tailscale.com>
This commit is contained in:
Percy Wegmann 2024-08-21 10:10:13 -05:00 committed by Percy Wegmann
parent 690d3bfafe
commit 4637ac732e
2 changed files with 16 additions and 7 deletions

View File

@ -247,8 +247,17 @@ func (b *LocalBackend) driveSetSharesLocked(shares []*drive.Share) error {
}
// driveNotifyShares notifies IPN bus listeners (e.g. Mac Application process)
// about the latest list of shares.
// about the latest list of shares, if and only if the shares have changed since
// the last time we notified.
func (b *LocalBackend) driveNotifyShares(shares views.SliceView[*drive.Share, drive.ShareView]) {
b.lastNotifiedDriveSharesMu.Lock()
defer b.lastNotifiedDriveSharesMu.Unlock()
if b.lastNotifiedDriveShares != nil && driveShareViewsEqual(b.lastNotifiedDriveShares, shares) {
// shares are unchanged since last notification, don't bother notifying
return
}
b.lastNotifiedDriveShares = &shares
// Ensures shares is not nil to distinguish "no shares" from "not notifying shares"
if shares.IsNil() {
shares = views.SliceOfViews(make([]*drive.Share, 0))
@ -265,12 +274,9 @@ func (b *LocalBackend) driveNotifyCurrentSharesLocked() {
shares = b.pm.prefs.DriveShares()
}
lastNotified := b.lastNotifiedDriveShares.Load()
if lastNotified == nil || !driveShareViewsEqual(lastNotified, shares) {
// Do the below on a goroutine to avoid deadlocking on b.mu in b.send().
go b.driveNotifyShares(shares)
}
}
func driveShareViewsEqual(a *views.SliceView[*drive.Share, drive.ShareView], b views.SliceView[*drive.Share, drive.ShareView]) bool {
if a == nil {

View File

@ -332,9 +332,12 @@ type LocalBackend struct {
// Last ClientVersion received in MapResponse, guarded by mu.
lastClientVersion *tailcfg.ClientVersion
// lastNotifiedDriveSharesMu guards lastNotifiedDriveShares
lastNotifiedDriveSharesMu sync.Mutex
// lastNotifiedDriveShares keeps track of the last set of shares that we
// notified about.
lastNotifiedDriveShares atomic.Pointer[views.SliceView[*drive.Share, drive.ShareView]]
lastNotifiedDriveShares *views.SliceView[*drive.Share, drive.ShareView]
// outgoingFiles keeps track of Taildrop outgoing files keyed to their OutgoingFile.ID
outgoingFiles map[string]*ipn.OutgoingFile