webnet/tailscale
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

ipn/ipnlocal: reduce allocations in TailFS share notifications

Browse Source 
This eliminates unnecessary map.Clone() calls and also eliminates
repetitive notifications about the same set of shares.

Updates tailscale/corp#16827

Signed-off-by: Percy Wegmann <percy@tailscale.com>
This commit is contained in:
Percy Wegmann
2024-02-29 13:49:45 -06:00
committed by Percy Wegmann
parent 6f66f5a75a
commit fd942b5384
2 changed files with 25 additions and 28 deletions
Download Patch File Download Diff File Expand all files Collapse all files
ipn/ipnlocal/tailfs.go
+18 -23
View File
@@ -7,7 +7,6 @@ import (
"encoding/json"
"errors"
"fmt"
"maps"
"os"
"regexp"
"strings"
@@ -115,7 +114,7 @@ func (b *LocalBackend) tailfsAddShareLocked(share *tailfs.Share) (map[string]*ta
return nil, errors.New("tailfs not enabled")
}
shares, err := b.tailFSGetSharesLocked()
shares, err := b.TailFSGetShares()
if err != nil {
return nil, err
}
@@ -130,7 +129,7 @@ func (b *LocalBackend) tailfsAddShareLocked(share *tailfs.Share) (map[string]*ta
}
fs.SetShares(shares)
return maps.Clone(shares), nil
return shares, nil
}
// TailFSRemoveShare removes the named share. Share names are forced to
@@ -161,7 +160,7 @@ func (b *LocalBackend) tailfsRemoveShareLocked(name string) (map[string]*tailfs.
return nil, errors.New("tailfs not enabled")
}
shares, err := b.tailFSGetSharesLocked()
shares, err := b.TailFSGetShares()
if err != nil {
return nil, err
}
@@ -180,7 +179,7 @@ func (b *LocalBackend) tailfsRemoveShareLocked(name string) (map[string]*tailfs.
}
fs.SetShares(shares)
return maps.Clone(shares), nil
return shares, nil
}
// tailfsNotifyShares notifies IPN bus listeners (e.g. Mac Application process)
@@ -189,28 +188,24 @@ func (b *LocalBackend) tailfsNotifyShares(shares map[string]*tailfs.Share) {
b.send(ipn.Notify{TailFSShares: shares})
}
// tailFSNotifyCurrentSharesLocked sends an ipn.Notify with the current set of
// TailFS shares.
func (b *LocalBackend) tailFSNotifyCurrentSharesLocked() {
shares, err := b.tailFSGetSharesLocked()
if err != nil {
b.logf("error notifying current tailfs shares: %v", err)
return
}
// Do the below on a goroutine to avoid deadlocking on b.mu in b.send().
go b.tailfsNotifyShares(maps.Clone(shares))
// tailFSNotifyCurrentSharesOnce sends a one-time ipn.Notify with the current
// set of TailFS shares.
func (b *LocalBackend) tailFSNotifyCurrentSharesOnce() {
b.notifyTailFSSharesOnce.Do(func() {
shares, err := b.TailFSGetShares()
if err != nil {
b.logf("error notifying current tailfs shares: %v", err)
return
}
// Do the below on a goroutine to avoid deadlocking on b.mu in b.send().
go b.tailfsNotifyShares(shares)
})
}
// TailFSGetShares returns the current set of shares from the state store,
// stored under ipn.StateKey("_tailfs-shares").
// stored under ipn.StateKey("_tailfs-shares"). The caller owns this map and
// is free to mutate it.
func (b *LocalBackend) TailFSGetShares() (map[string]*tailfs.Share, error) {
b.mu.Lock()
defer b.mu.Unlock()
return b.tailFSGetSharesLocked()
}
func (b *LocalBackend) tailFSGetSharesLocked() (map[string]*tailfs.Share, error) {
data, err := b.store.ReadState(tailfsSharesStateKey)
if err != nil {
if errors.Is(err, ipn.ErrStateNotExist) {